MedPath Exam 2: Practice Questions

A 19-year-old woman presents with a 2-week history of rash. Other than a sore throat that she had last week, she reports being in good health; her sore throat was treated with penicillin. She does not believe that she has come in contact with any type of irritants or any individuals who are sick. On physical examination, you note several target-like lesions on the palms of her hands that are bilateral and symmetric. She indicates that she is on birth control medication. What is the most likely diagnosis? A) Erythema multiforme B) Erysipelas C) Atopic dermatitis D) Erythema nodosum E) Steven-Johnson syndrome

A) Erythema multiforme These clinical findings are suggestive of erythema multiforme, a cutaneous reaction to various antigenic stimuli. Examples include viral infections (herpes simplex is the most common cause) or drugs (penicillin, sulfonamides). 50% of cases are idiopathic and about 50% of patients can have flu-like symptoms up to 2 weeks before the rash develops. The lesions progress from macules to papules with a zone of central clearing, appearing as target-like lesions. Lesions can occur on skin and/or mucosa, and severity of disease can vary widely from patient to patient.

A 28-year-old man presents with a 1-week history of an itchy scaly rash on his elbows. When he scratches it hard, scales come off and the rash bleeds. Examination reveals the elbows are affected bilaterally. The lesions appear as 3-4 cm annular whitish scales on an erythematous base that is irregular and well-demarcated. The antecubital fossa are unaffected. What is an appropriate treatment? A) Topical fluorinated glucocorticoids B) Mineral oil C) Benzoyl peroxide gel D) Topical metronidazole E) Aluminum chloride hexahydrate

A) Topical fluorinated glucocorticoids The clinical picture is suggestive of localized plaque psoriasis. Since the lesions are localized to the elbows with <5% skin involvement, the treatment includes topical fluorinated glucocorticoids. The appropriate treatment is applying glucocorticoids and covering the area with plastic wrap.

A 16-year-old girl has had acne breakouts since age 10, and both she and her mother have noted the breakouts worsening significantly every year. She notes worsening of her breakouts around her menses each month, but she states she has multiple lesions consistently throughout the month. She has a history of using diet modification, topical retinoids, benzoyl peroxide, and two types of oral antibiotics without improvement. Physical examination of the patient reveals extensive open and closed comedones on the forehead, cheeks, and chin. Painful cystic lesions are present throughout. Isotretinoin is now considered. How often will this patient need to have a serum pregnancy test once the treatment regimen has begun? A) Every week B) Every 3 weeks C) Every 4 weeks D) Every 6 weeks E) Every 8 weeks

C) Every 4 weeks This medication is known to be extremely teratogenic, so usage is an absolute contraindication during pregnancy. Before treatment, female patients are required to have two serum pregnancy tests. While on isotretinoin therapy, female patients are required to obtain serum pregnancy tests every 4 weeks. If sexually active, female patients are also instructed to use two forms of contraception to prevent pregnancy. A stringent monitoring program is in place, along with the initial consent form to ensure that these strict precautions are followed (iPLEDGE).

A 45-year-old woman presents with a lesion on her calf. She states that she has had it for a while and that it has not gotten bigger, but it does not heal and it bleeds occasionally. On exam, the lesion is a pink sharply demarcated scaling plaque. What is the most likely diagnosis? A) Seborrheic keratosis B) Malignant melanoma C) Squamous cell carcinoma D) Verruca wart E) Lichen planus

C) Squamous cell carcinoma This is a clinical picture of squamous cell carcinoma (SCC). Most SCC appears as a sharply demarcated, scaling, or hyperkeratotic macule, papule, or plaques. They are most often asymptomatic, but they may bleed. SCC is most often caused by UV radiation (sun exposure) or HPV infection.

A 39-year-old woman presents with a rash. The rash started 5 days ago; it is pruritic and located primarily on her arms and legs, with a few sores in her mouth. Her husband described the rash as like a "bullseye." She has felt mildly "flu-like," but she denies fevers. She denies any changes in soaps, detergents, or diet. She has not been around anyone with a similar condition, and she denies travel. Otherwise, she reports feeling better than usual, with more improved control of her migraines since her neurologist started her on topiramate about 3 weeks ago. She has not needed to use her sumatriptan for over 1 month. Her review of systems is negative. She suffers from migraines, but she has no other chronic health conditions. Her current medications are topiramate daily, with sumatriptan as needed. She is allergic to amoxicillin. She has regular menses; she had a tubal ligation as contraceptive. On physical exam, a few small oral lesions are noted. The lesions on the extremities are primarily on the dorsal surfaces, with a ringed appearance, similar to a target. The remainder of her exam is normal, including vital signs. What is the most important and appropriate intervention in this case? A) Admission to burn unit for skin management B) High-dose oral antihistamines C) High-dose oral steroids D) Immediate discontinuation of the new medication E) Topical steroid cream

D) Immediate discontinuation of the new medication This patient is presenting with a target lesion rash; it is typical of erythema multiforme, which is a relatively common type IV hypersensitivity reaction. In about 50% of cases of erythema multiforme, no cause is identified. Other causes are infection and medications, including anticonvulsants. This patient's rash occurrence suspiciously followed the initiation of a new medication. Erythema multiforme is an acute, self-limited condition; it can range in severity from a rash, mild malaise, and pruritus (erythema multiforme minor) to a much more severe condition, involving mucosal surfaces and possible desquamation with erythema multiforme major. The most important treatment of erythema multiforme when a medication is attributed as the cause is immediate discontinuation of the new medication.

An 82-year-old man presents for evaluation of an itchy hive-like rash on his abdomen. He has had it for months. Over the last few days, the patient reports the character of the rash has changed; it now resembles blisters. Other than some skin irritation, he feels healthy. He has tried multiple over-the-counter topical treatments, but they have been unsuccessful in treating the rash. He denies any changes in soaps, lotions, laundry detergents, or anything else that may have come in contact with his skin. He also denies unusual travel, pets, or hobbies. No close contacts have reported a similar condition. He takes no medications, and he does not have any chronic illnesses. On physical exam, multiple clusters of bullae are noted across the trunk bilaterally, with some distribution on both anterior and posterior surfaces. There are still some remaining pink-red lesions; they are scattered among the bullae. The bullae are 1-3 cm in size; they are tense and do not easily rupture. They do not extend into normal skin with pressure. Pressure on the normal skin does not produce a blister. The remainder of his physical exam is normal. Once you confirm the diagnosis, what intervention is most appropriate for this patient's condition? A) Apply trichloroacetic acid (TCA) or bichloroacetic acid (BCA). B) Cryotherapy of bullous lesions. C) Dermabrasion D) Oral prednisone E) Topical acyclovir

D) Oral prednisone This patient is presenting with bullous pemphigoid (BP), a benign autoimmune skin disorder characterized by the presence of bullae (or blisters). BP is relatively rare and tends to affect the elderly population. The preceding rash is typically pruritic and appears as urticarial plaques, possibly resembling erythema multiforme. This stage may last for months, and then the skin blisters. When the blisters rupture (typically within 1 week), the skin heals. Unless the BP is extensive and generalized, the prognosis is good. Oral steroids, such as prednisone, have been the primary treatment, but other approaches, such as antihistamines for pruritus, topical steroids, antibiotics, methotrexate, and azathioprine, may all have a role in treating BP.

A 45-year-old Caucasian woman presents because she is worried she may have skin cancer. While interviewing the patient, you note the patient has an extremely fair complexion. When you examine the lesions that the patient is concerned about, you note the following description in your documentation: "5 papules that vary in diameter from 0.3-0.6 centimeters dispersed on the skin around the sternal angle. Lesions vary in color from flesh-toned to slightly hyperpigmented, and when palpated have a sandpaper texture." Based on the most likely diagnosis, what would be the most appropriate pharmaceutical regimen at this time? A) 5-fluorouracil cream B) Benzoyl peroxide cream C) Clindamycin gel D) Hydroquinone E) Ketoconazole cream

A) 5-fluorouracil cream Topical treatment for AK usually will be with either 5-fluorouracil (5-FU), imiquimod cream, or diclofenac gel, with 5-FU cream being the mainstay of topical treatment for the past several decades. Benzoyl peroxide and clindamycin topical gel are utilized most commonly in acne vulgaris patients. Hydroquinone cream is utilized as a type of skin-bleaching agent to help lighten freckles, melasma, or trauma. Ketoconazole is a treatment for tinea or seborrhea infections.

A 15-year-old boy is being treated at the dermatologist for lesions on his cheeks, forehead, chin, upper chest, and upper back with a history that has been progressively getting worse. Upon physical exam, open and closed comedones are present on the patient. Additionally, inflamed papules and some scarring are present. All labs are within normal limits. What is the most likely diagnosis? A) Acne vulgaris B) Contact dermatitis C) Folliculitis D) Miliaria E) Rosacea

A) Acne vulgaris The clinical picture is suggestive of acne vulgaris due to the physical presentation of open and closed comedones. Additionally, the puberty age, location of comedones, and appearance of inflamed papules with some scarring are typical features of acne vulgaris.

A 65-year-old man is being treated at the dermatologist for a lesion on his face for the past 5 weeks that will not go away. Additionally, the patient has a history of staying out in the sun, as he lives in Florida. Upon physical exam, a 0.6 cm macule that appears flesh-colored and slightly hyperpigmented is present on his right cheek. Upon palpation, the macule feels like sandpaper and is tender to the patient. All labs are within normal limits. What is the most likely diagnosis? A) Actinic keratoses B) Bowen disease C) Exfoliative dermatitis D) Intertrigo E) Mycosis fungoides

A) Actinic keratoses The patient presents with a flesh-colored hyperpigmented macule that is present on a sun-exposed part of the body, and the sandpaper appearance is a common description of actinic keratoses. Bowen disease lesions are not described as sandpaper appearance. Lesions present as red-colored plaques with an irregular border. It is an early skin cancer that is diagnosed, and this patient is older than when it would normally be diagnosed.

A 45-year-old woman presents with a skin lesion. She states she noticed a lesion on her cheek for the past few weeks and it will not go away. She has a history of laying out in the sun at her home in Florida since she was a teenager. Upon physical exam, the patient has a wart that appears to be elevated and pink with a sandpaper texture. What is the most likely diagnosis? A) Actinic keratosis B) Basal cell cancer C) Melanoma D) Melasma E) Squamous cell skin carcinoma

A) Actinic keratosis This patient presents with sandpaper-textured elevated pink wart-appearing lesions in a sun-exposed area, which is consistent with actinic keratosis.

A 3-year old boy is brought to the pediatrician with a 2-week history of symptoms of an itchy, red "wound" on the right knee. The mother ignored the wound initially, assuming that the boy got injured while playing on the street, but it did not heal and seems to have worsened. On examination, there are a few intact vesicles and a few ruptured vesicles covered with honey-colored crusts. You suspect non-bullous impetigo. What treatment will you prescribe? A) Antibiotic ointment B) Steroid ointment C) Emollient cream D) Oral antibiotics E) Oral steroids

A) Antibiotic ointment Treatment is with proper wound care and topical antibiotics like mupirocin or retapamulin. The bullous type is characterized by large bullae, along with fever, diarrhea, weakness, etc. Topical or oral steroids are not indicated in skin infections. Oral antibiotics are usually not necessary in non-bullous impetigo, although they may be indicated in extensive bullous lesions. Emollients are not necessary in impetigo.

A 24-year-old woman notices that she has a bruising tendency. She frequently has numerous small bruises and purple blotches on her skin. She hates having dental work because of the associated bleeding. On physical exam, you note that she has numerous petechiae. Her lab results are shown in the chart. TEST RESULTS//REFERENCE RANGE Hematocrit 42//36-44 (female) Hemoglobin 14 gm/dL//12.1-15.1 gm/dL (female) Platelets 41,000/mm//3130,000-400,000/mm3 PT 11.5 seconds//10.8-13.0 seconds PTT 30 seconds//25-41 seconds RBC 4.8 x 106/µl//3.9-5.0 x 106/µL (female) The patient's condition is most likely to be characterized by what? A) Antiplatelet IgG B) Decreased number of megakaryocytes C) Spontaneous resolution D) Requiring confirmation by bone marrow biopsy E) Hemorrhagic death likely

A) Antiplatelet IgG Antiplatelet IgG is seen with most patients with immune (idiopathic) thrombocytopenic purpura (ITP), which is the most likely diagnosis in this patient. The underlying pathophysiology of ITP is that there is an increased destruction of platelets in the peripheral circulation. A decreased number of megakaryocytes would not be seen with ITP. The marrow will therefore either have a normal number of megakaryocytes or an increased number of megakaryocytes, but certainly not a decrease. ITP in adults usually becomes chronic. It does not usually spontaneously disappear. Hemorrhage is the most serious complication of ITP. Hemorrhagic death in adults with ITP does sometimes occur, but it is not inevitable. Bone marrow biopsy was previously considered a routine diagnostic test for ITP but is no longer required for diagnosis confirmation.

A 62-year-old woman well known to you presents with a severely itchy rash. The patient's medical history includes Parkinson's disease that was diagnosed around 7 years ago. The patient thought that the rash was just eczema initially, but the areas have morphed into severely tense, large blisters; they are extremely pruritic to the patient. On examination, you note multiple bullae 1-3 cm in size that are tense and appear to be sitting on an erythematous base. The bullae are located on the patient's lower abdomen in both lower quadrants and in the bilateral axillary and inguinal folds. What is the most likely diagnosis? A) Bullous pemphigoid B) Herpes zoster C) Pemphigus vulgaris D) Tinea corporis E) Varicella

A) Bullous pemphigoid This patient has bullous pemphigoid (BP), an autoimmune blistering disorder that most commonly occurs in older adults (typically those over 60). Neurological disorders have an association with the development of bullous pemphigoid, and Parkinson's disease is an independent risk factor. Areas affected include the trunk, extremity flexures, and axillary or inguinal folds. There may be a prodromal phase where the patient experiences pruritic eczematous, papular, or urticarial-like skin lesions. Classic lesions of BP are 1-3 cm tense bulla on an erythematous, urticarial, or non-inflammatory base. The blisters will be plentiful, widespread, and severely pruritic.

A 5-year-old girl presents with a rash of clear and grayish vesicles on a reddened base. Her hands and feet are affected, including her palms and soles. She reports sores in her mouth. There is no desquamation to the rash. Her heart and lungs are clear. She is febrile, and there is an accompanying tachycardia. Her blood pressure is normal. Her oral cavity shows ulcerations. What is the most likely diagnosis? A) Hand-foot-mouth disease B) Measles C) Kawasaki disease D) Toxic shock syndrome E) Rocky Mountain spotted fever

A) Hand-foot-mouth disease Hand-foot-mouth disease, a childhood disease, is a rash consisting of vesicles on a reddened base. The hands and feet are the most common body parts affected. Oral ulcers or vesicles can be seen. Fever sometimes occurs with the other symptoms. Coxsackievirus is the etiologic agent of hand-foot-mouth disease. The typical time for hand-foot-mouth disease to occur is during the summer and fall.

A 21-year-old woman presents with recurrent painful nodules that form in her armpits. On physical examination, you note red inflammatory nodules that are very tender to palpation. Also noted are open comedones that seem to be paired. The patient indicates that these areas ultimately break down and drain a foul-smelling purulent material. What is the most likely diagnosis? A) Hidradenitis suppurativa B) Roth spots C) Sebaceous gland hyperplasia D) Cellulitis E) Acanthosis nigricans

A) Hidradenitis suppurativa The clinical picture is suggestive of hidradenitis suppurativa. The age of onset begins at puberty and it affects females more than males. The initial lesions appear as red inflammatory nodules or abscesses that are very tender. They may resolve, or they may drain purulent material. The lesions may reoccur in the same area. Their distribution is localized to the axillae, breasts, anogenital area, and groin. They may have a unique "double comedone" appearance that is highly characteristic of this disorder.

A 4-year-old girl presents with her mother to discuss treatment of her atopic dermatitis. She was diagnosed as an infant, but her case appears to be getting worse despite frequent lubrication with thick emollient creams and medium-potency topical corticosteroid use. The mother states that the patient is itching a lot more, especially during the night. Large, single patches of erythematous scaly excoriations measuring about 3 cm x 4 cm are present in the flexor surfaces of both elbows. What is the most appropriate therapy for these symptoms? A) High-potency topical corticosteroids B) Topical antihistamines C) Oral antihistamines D) Systemic anti-staphylococcal antibiotics E) Ketoconazole cream

A) High-potency topical corticosteroids Since a medium-potency corticosteroid topical has been attempted, high-potency steroids are the next step in treatment. Other options include topical tacrolimus, phototherapy, and oral cyclosporine.

A young woman presents with her daughter, who appears to be about 6 years old. You note that the child's eyes are downcast and she is scratching her scalp. On closer inspection, you note a tiny white wingless insect and tiny eggs attached to the hair shafts. The child's mother also notes that the same insects are present in the girl's eyelashes. What is the most likely diagnosis? A) Lice B) Scabies C) Thrush D) Ringworm E) Dandruff

A) Lice The gold standard for diagnosing lice is finding a live louse on the head. Lice feed by biting the skin and sucking the blood of the individual on which they are living. The bites cause itching, so the infected person tends to scratch. Non-prescription medications can be used to treat the infestation.

A 15-year-old girl with a recent history of epilepsy presents 1 week after evaluation by a neurologist for prophylactic anti-seizure medication. She was placed on phenytoin by the neurologist at that time. Today, she reports a 3-day history of fever, myalgias, non-productive cough, sore throat, and several episodes of non-bilious vomiting. She states that a non-pruritic rash has developed, first at her hands and feet and now beginning to "move up her arms and legs." On exam, symmetric circular papular lesions with central pallor are present. What is an additional expected clinical manifestation in this patient? A) Mucosal erosions B) Positive Nikolsky sign C) Constipation D) Hypoventilation E) Peripheral edema

A) Mucosal erosions Mucosal involvement is present in up to 70% of patients with erythema multiforme. Erosions of the oral mucosa may result in difficulty eating, drinking, or opening the mouth. The degree is usually mild, limited to one mucosal surface. The most common sites of mucous membrane involvement in order of frequency are the oropharynx (lips, palate, and gingiva most often affected), conjunctivae, genitalia, anus, tracheobronchial tree, esophagus, and bowel. Eye involvement (10%) is usually mild and may manifest as red conjunctivae, chemosis, and lacrimation. The genital areas may have painful hemorrhagic bullae and erosions. More severe erosions of at least two mucosal surfaces are seen in erythema multiforme major and are characterized by hemorrhagic crusting of the lips and ulceration of the non-keratinized mucosa. Nikolsky sign is negative; the top layers of the skin do not slip away from the lower layers when slightly rubbed. Constipation is not an anticipated finding. Rather, profuse diarrhea occurs from involvement of bowel mucosa. Shortness of breath and hyperventilation with mild hypoxia may result from anxiety or tracheobronchial epithelial involvement.

A 10-year-old girl presents with her mother and reports "really bad dandruff that itches like crazy." The child states that all of her friends at school have it too. Upon physical examination of the hair and scalp, you note numerous oval grayish-white sesame seed capsules 1-2 mm in size deposited on the hair shaft near the scalp. Small red bumps and sores on the scalp appear to be due to the patient scratching. What is the most likely diagnosis? A) Pediculosis B) Psoriasis C) Seborrheic dermatitis D) Trichorrhexis nodosa E) Atopic dermatitis

A) Pediculosis The clinical picture is suggestive of pediculosis capitis. The oval grayish-white sesame seed capsules 1-2 mm in size deposited on the hair shaft near the scalp represent the eggs laid by the parasite Pediculosis humanis capitis. This is seen in girls more than boys, ages 3-11.

A 4-year-old boy presents with a rash on his feet, ankles, wrists, and gluteal areas; the rash is accompanied by severe itching, particularly at night. His 6-month-old sister has a similar rash on her neck and head. On examination, you find pruritic erythematous papular and papulopustular skin changes between the web spaces of the fingers; changes are also seen on the flexor aspects of the wrists and in the genital and gluteal areas. On superficial epidermis, you find several short elevated red tortuous lines; they have a small vesicle at the tip. What treatment you will suggest? A) Permethrin cream B) Hydrocortisone cream C) Clindamycin lotion D) Selenium sulfide lotion E) Tar soap

A) Permethrin cream Both your patient and his sibling most probably have scabies: the pathognomonic sign is a short elevated pink or gray track that is straight or tortuous in the superficial epidermis; there is also a small vesicle at the tip (burrow). Topical permethrin is the drug of choice.

A 21-year-old man presents with itchy skin changes. He works as a lifeguard. About a week ago, he noticed a round red patch on his belly that spread to his trunk and legs. He denies recent infections, allergies, and illnesses; he does not take any medications, and he admits that he occasionally smokes marijuana. The rest of his personal and family history is non-contributory. On examination, you find round annular scaly pruritic papulosquamous changes on his torso and legs. There are no changes on his mucosa, and the rest of physical examination is within normal limits. What is the next step in making the diagnosis? A) Potassium hydroxide preparation B) Skin biopsy C) Venereal disease research laboratory test D) Intradermal prick test E) Tzanck smear of the lesion

A) Potassium hydroxide preparation The clinical picture of skin changes and the patient's occupational history suggest tinea corporis. You should confirm the diagnosis with potassium hydroxide preparation of skin scrapings that will demonstrate the presence of fungal hyphae. If the potassium hydroxide test is negative, then you should consider a skin biopsy to identify the pathohistological patterns of the other dermatoses.

The 26-year-old HIV-positive man has a CD4 count <200. While he was in the hospital for the treatment of his miliary Tb, he developed smooth skin-colored umbilicated papules on his face. The lesions are asymptomatic, but they are spreading gradually to other parts of the body and causing cosmetic problems to the patient. What organism is the most likely cause of this skin infection? A) Poxvirus B) Human papillomavirus C) Parvovirus B19 D) Herpes simplex virus type E) Epstein-Barr virus

A) Poxvirus This patient has typical lesions of Molluscum contagiosum, a poxvirus infection characterized by skin-colored smooth waxy umbilicated papules 2-10 mm in diameter. Transmission can be direct or venereal. Its contagiousness to others varies. The lesions may be seen anywhere on the skin, face, body or genital area. They are usually asymptomatic unless secondarily infected. This disease is quite common in children, and the lesions can be widespread in patients with reduced cellular immunity.

A 38-year-old woman gave birth to a healthy female neonate 3 months ago. Her pregnancy and vaginal delivery were unremarkable. Over the past 3 months, she developed increased oral bleeding with hemorrhagic bullae. Based on the most likely diagnosis, the presence of which of the following makes immune thrombocytopenic purpura less likely? A) Splenomegaly B) Petechiae C) Megakaryocytosis D) Increased bruising E) Epistaxis

A) Splenomegaly Immune thrombocytopenic purpura (ITP) does not typically cause an enlarged spleen despite the destruction of platelets in the spleen. If an enlarged spleen is identified, it should alert the clinician to consider other possible causes for the patient's thrombocytopenia. Typically, ITP is a diagnosis of exclusion once other hematologic abnormalities for thrombocytopenia are ruled out. In the majority of cases, it is found to be an autoimmune disorder with the creation of anti-platelet antibodies. Petechiae, increased bruising, and epistaxis are common findings in ITP. Megakaryocytosis is typically seen in ITP, as immature platelets are large due to increased production.

A 16-year-old Caucasian girl presents with a 6-month history of blackheads and whiteheads on her face. On examination, there are a few papules and pustules on her cheeks; there are no nodules. Her mother reports having similar spots on her face at this age. What is an appropriate first-line medication for this patient? A) Tretinoin B) Isotretinoin C) Doxycycline D) Minocycline E) Triamcinolone

A) Tretinoin Topical retinoids (tretinoin, adapalene, tazarotene) are effective first-line treatments for mild acne. Tretinoin is a comedolytic that inhibits follicular canal obstruction by normalizing keratinocyte shedding, which inhibits microcomedone formation. It also has anti-inflammatory properties.

A 32-year-old man with a past medical history of allergic rhinitis and asthma that is well-controlled complains of recurrent pruritus associated with an erythematous rash in the flexural areas of his elbows and knees. The lesions seem to become worse when he scratches them and when he is under stress. He denies any recent insect bites, travel, fever, chills, new clothing, or detergent use. Physical examination reveals rough-appearing erythematous plaques in the bilateral antecubital and popliteal fossae, with areas of excoriations within the lesions. What intervention is most appropriate at this time? A) Triamcinolone 0.1% applied to the lesions once or twice daily B) Cephalexin 500 mg by mouth every 12 hours C) Acyclovir 200 mg by mouth 5 times per day D) Tacrolimus ointment 0.03% applied to the lesions twice daily E) Prednisone 40 mg by mouth daily tapered over 2-4 weeks

A) Triamcinolone 0.1% applied to the lesions once or twice daily he dermatologic lesions described in this patient, along with his coexisting past medical history, are most indicative of an eczematous eruption. Corticosteroids should be applied sparingly to the dermatitis once or twice daily and rubbed in well. In general, one should begin with triamcinolone 0.1% or a stronger corticosteroid and then taper to hydrocortisone or another slightly stronger mild corticosteroid.

An 8-year-old girl presents with a 3-month history of hair loss. Except for usual minor childhood illnesses such as colds and ear infections, she has been in good health since birth. 3 months ago, her mother noted small bald areas developing on the girl's scalp when she brushed her hair. The child denies any pain or itching of the scalp, and she denies pulling at her hair. There have been no other symptoms. She has not taken any medications, and she has no known allergies. On exam, you find three round smooth silver dollar-sized areas of complete hair loss. The scalp is normal. What is the most likely diagnosis? A) Toxic alopecia B) Alopecia areata C) Tinea capitis D) Traction alopecia E) Trichotillomania

B) Alopecia areata Alopecia areata is characterized by hair loss in round or oval patches on the scalp. The skin within the plaques of hair loss is normal. Alopecia areata occurs in 1% of the population; many patients are under 20. It is associated with atopy and autoimmune diseases. The course of alopecia areata is unpredictable, but it may resolve spontaneously in 6-12 months. Occasionally, high potency topical steroid preparations are prescribed.

A 5-year-old boy presents with an erythematous skin rash associated with intense itching. The boy's mother has noticed that her son's rash has been recurrent, with 3-4 episodes per year. The itching and rash increases after consumption of certain foods. On examination, erythematous raised papules are seen on the cheek, trunks, and upper arms. What is most likely associated with the boy's condition? A) Gluten enteropathy B) Asthma C) Vitamin A deficiency D) Psoriasis E) Raised dengue titers

B) Asthma The vignette describes a child with atopic dermatitis (AD), one of the most common childhood dermatological conditions. It usually begins before age 2 and displays a chronic relapsing course. Typical sites of involvement are the cheeks, flexural aspect of the elbows, natal cleft, and the hands. Clinical examination usually reveals xerosis, lichenification, and eczematous lesions. Atopic dermatitis is commonly associated with other atopic conditions, such as hay fever, extrinsic asthma, allergic conjunctivitis, and allergic rhinitis. A high IgE level and eosinophilia are common to all of these. In some patients, especially children, sensitization to foods such as egg or wheat can occur. In 33% of patients with severe AD, 10-20% of patients with moderate AD, or 6% of patients with mild AD, food allergies can exacerbate AD. Food allergy can be confirmed with skin testing or testing food specific IgE.

A 7-year-old girl was playing at a local playground near her home in Louisiana. She was playing kickball and retrieved the ball from a pile of rocks. After several minutes, she noticed a red lesion on her right forearm. She rushed home and told her mom. The mother looked at the lesion and noticed a small red area and sprayed the area with a local antiseptic that she had in her medicine cabinet. The child only noted that it burned. A few hours later, the mother looked at the area and noticed that a white area appeared. She thought nothing of it and placed a bandage over the bite. Before the child went to bed that night, she removed the bandage and noticed that the area had darkened. The mother then took the child to the ER for further evaluation. What most likely inflicted this envenomation? A) Black widow spider B) Brown recluse spider C) Centipede D) Dermacentor andersoni tick E) Scorpion

B) Brown recluse spider The clinical picture is suggestive of a brown recluse spider bite. The bite usually produces localized burning, followed by a white area in 3-4 hours due to vasoconstriction, which can progress to local tissue necrosis after a few hours to days. Black widow spider bites most commonly cause generalized muscular pain, muscle spasms, and rigidity.

A 48-year-old previously healthy African American woman was involved in a severe motor vehicle accident, sustaining multiple injuries. She was stabilized in the emergency department but is now bleeding extensively from her laceration sites, her IV catheter site, and from mucous membranes. Laboratory results show thrombocytopenia, fragmented red blood cells, and low fibrinogen levels. What is the most likely diagnosis? A) Factor V deficiency B) Disseminated intravascular coagulation C) Factor XI deficiency D) Protein C and S deficiency E) Acute idiopathic thrombocytopenia purpura

B) Disseminated intravascular coagulation This patient's severe injuries triggered the mechanisms of disseminated intravascular coagulation (DIC). In DIC, traumatized or necrotic tissue releases tissue factor into the circulation, which triggers coagulation reactions. Thrombi and emboli develop. The thrombotic phase is followed by fibrinolysis. Hemorrhage results from depletion of coagulation factor and platelets. Diagnosis of DIC is made by thrombocytopenia, fragmented red blood cells, prolonged PT and PTT, decreased fibrinogen, and increased fibrin degradation products.

A 4-year-old girl is brought by her mother to the ED for swelling and redness of the left elbow. The mother tells you that the child fell onto the elbow 4 days ago and sustained a small abrasion. The child scratched and picked at the wound for 2 days and subsequently developed redness around the site and purulent drainage from the wound. Yesterday, the elbow became quite swollen and the child had a fever of 103°F. The mother states that the area of redness has increased rapidly over the past 24 hours. What organism is most likely to cause these findings? A) Pseudomonas aeruginosa B) Group A Streptococcus C) Clostridium perfringens D) Enterococcus faecalis E) Peptostreptococcus

B) Group A Streptococcus The patient has left elbow cellulitis most likely caused by Group A Streptococcus, the causative agent for many pediatric infections, most commonly acute pharyngitis, impetigo, pneumonia, bacteremia, and vaginitis. Trauma to the skin such as laceration, puncture wound, or abrasion predisposes to the formation of cellulitis. Another common organism causing cellulitis is Staphylococcus aureus. The classic findings of cellulitis are local tenderness, erythema, and pain. Fever, chills, and malaise often develop. The lesion is usually red, warm, and swollen. Toxic shock syndrome and septic arthritis are two other conditions that can be caused by both Staphylococcus and Streptococcus.

A 20-month-old boy presents with a 1-week history of fever up to 101°F and irritability. His mother noted sores in his mouth 4 days ago; she states that she has noticed him drooling and that his appetite is quite diminished. His past medical history is unremarkable. He has no medical allergies and his only current medication is acetaminophen. He is current on his immunizations. His physical exam reveals normal vital signs except for a temperature of 100.5°F. On examination of his oral cavity, you note swollen erythematous gingiva with ulcerations present mostly on the left of his mouth. The ulcerations appear yellowish-white and friable. White-gray lesions approximately 3 mm in diameter are seen on the anterior tongue. The tonsils appear erythematous without exudates. His lips are slightly cracked, and his mucous membranes are slightly tacky. Neck examination reveals bilateral anterior cervical adenopathy. He has no skin lesions. The remainder of his exam is normal. His strep test is negative. What is the most likely cause of this patient's condition? A) Oral candidiasis B) Herpetic gingivostomatitis C) Herpangina D) Nursing bottle caries E) Foreign body impaction

B) Herpetic gingivostomatitis Herpetic gingivostomatitis, caused by herpes simplex virus type 1, is the most common cause of stomatitis in children 6 months to 5 years old. Symptoms may appear abruptly, with fever, drooling, fetid breath, and refusal to eat. The fever may precede the oral lesions by 4 days and presage to a more insidious onset of the disease. The tongue, cheeks, and gingiva are most commonly affected, but the entire oral cavity may be involved. These areas can present with ulcers that are yellowish-gray in color with a red halo surrounding the lesions, and the gingiva may be quite friable. Drooling may be present secondary to the pain associated with chewing and swallowing, and dehydration is a real concern in the management of the patient. Cervical and submaxillary adenitis is common. The acute phase may last 1-3 weeks. Treatment consists of measures to relieve the pain and facilitate the intake of fluids for adequate hydration. Oral acyclovir may be an option if caught within 72-96 hours and the child is having trouble with hydration due to painful lesions.

An 83-year-old woman is currently in a nursing home following a short hospitalization for a CVA. She experienced a thromboembolic stroke 2 weeks ago, which resulted in right hemiparesis and dysphagia. Other medical problems include congestive heart failure, atrial fibrillation, osteoarthritis, and depression. The nursing staff contacts you to reports a sacral pressure ulcer measuring 3 x 2 cm. On physical examination, there appears to be interruption of the epidermis with an abrasion. The lesion is clean; there is no cellulitis. After wound cleansing, what is the most appropriate management step? A) Dry dressings B) Moist dressing C) Apply povidone/iodine D) Topical antibiotics E) Systemic antibiotics

B) Moist dressing The patient in this case scenario has Stage II pressure ulcers, which are characterized by partial thickness skin loss of the epidermis and/or dermis, presenting as abrasion, blister, or shallow crater. Treatment of stage 2 pressure ulcer includes: - Keep the wound clean by washing the lesion with saline solution. Use gauze dressings moistened with saline to cover the skin, keep it clean, and retain the wound's natural fluids. Dry dressings or bandages can slow the healing process or make the sore worse. - Use prescribed ointments or creams, such as those that contain enzymes that may help speed the healing process. - Maintain a nutritional diet with adequate protein in order to promote healing and healthy skin. - Remove dead skin or tissue (debridement).

A mother brings her 5-year-old boy to the pediatrician due to multiple blisters on his cheek and nose. Physical examination is remarkable for numerous vesicles and crusted lesions containing light yellow fluid on both cheeks and around the nose. The child has similar lesions on his right wrist. What treatment is most appropriate? A) Bacitracin ointment B) Oral dicloxacillin C) Oral penicillin D) Oral tetracycline E) Mupirocin ointment

B) Oral dicloxacillin The clinical picture is suggestive of extensive impetigo. This child has lesions on their cheeks, nose, and wrists. Unless skin culture is significant for only group A Streptococcus, the oral antibiotic should be effective against both Staphylococcus aureus (β-lactamase-resistant penicillins or cephalosporins, clindamycin, amoxicillin-clavulanate) and Streptococcus for 7-10 days. The best choice for this patient would be either cephalexin or dicloxacillin. Penicillin V and tetracycline are not effective against Staphylococcus aureus infections.

A 3-year-old boy who weighs 14 kg presents with a 2-week history of severe itching all over the body that is more severe at night. Physical examination reveals gray thread-like serpentine lines with papules at the ends. There is a generalized papular and papulovesicular rash with few pustules. The lesions are more confluent between the webs of the fingers and toes and on the flexor surface of the wrists, axilla, genitalia, feet, and buttocks. Scrapings from the skin show an arthropod with four pairs of legs, hemispheric body, and brown spines and bristles on the dorsal surface. What is the treatment of choice for this child? A) Malathion 0.5% lotion B) Permethrin 5% cream C) Crotamiton 10% cream D) Ivermectin 3 mg orally E) Benzyl benzoate 25% cream

B) Permethrin 5% cream Permethrin 5% cream is an effective and convenient drug for a child with scabies. Toxicity of permethrin is very low and can be used in children ≥2 months and in pregnant women. >90% cure rates have been obtained in scabies. Overnight single application of 5% permethrin is required. All close contacts of the patient should be treated, even if asymptomatic. It may be reapplied after 1 week if required. Benzyl benzoate 25% lotion has been used for treatment of scabies. Benzyl benzoate is used in resource-limited areas and is not available in the US. The lotion is applied once daily at night for 2 consecutive days. Crotamiton 10% cream is effective in treatment of scabies, but it has produced lower cure rates than permethrin. The cream is applied, reapplied 24 hours later, then washed off 48 hours after initial application. An application extended 5 days consecutively has also been used. It is a second-choice drug for scabies. Ivermectin 3 mg orally is an anthelmintic drug found to be effective in scabies. It is administered orally in a single dose and gives a cure rate equal to that of permethrin, but it is not first-line treatment to children under 15 kg or to pregnant and lactating mothers. Malathion 0.5% lotion is used to treat scabies in children 6 and older. This lotion is flammable and has a high cost

A 17-year-old girl presents with a rash. She states she noted a single oval patch several days before a more generalized rash erupted. She indicates that the rash mildly itches. On physical examination, the initial lesion appears as an erythematous (salmon-colored) plaque with a collarette on the trailing edge of the advancing border. You note a fawn-colored rash that follows the cleavage lines on the posterior trunk. This rash is most prevalent on the trunk, and the proximal upper and lower extremities. What is the most likely diagnosis? A) Atopic dermatitis B) Pityriasis rosea C) Psoriasis D) Lichen planus E) Tinea corporis

B) Pityriasis rosea This is a clinical picture of pityriasis rosea. Initially, a single (primary or "herald") plaque lesion develops, usually on the trunk. One or two weeks later, a generalized secondary eruption develops in a typical distribution pattern. The "herald" patch occurs in 80% of patients. Lesions are usually confined to the trunk and proximal aspects of the arms and legs.

A 16-year-old girl has moderate facial acne vulgaris that you plan to treat with topical retinoids. What medical condition should you rule out before treating the patient with this class of drugs? A) Graves' disease B) Pregnancy C) Psoriasis D) Contact dermatitis E) Eczema

B) Pregnancy Tretinoin creams contain a retinoid metabolite of naturally occurring vitamin A; used topically, they are effective treatments for acne vulgaris. Unfortunately, retinoids are also potent teratogens; they have been shown to have effects on bone development in laboratory animals. Their use is contraindicated in pregnant women, so a pregnancy test should be performed before beginning treatment with topical retinoids

A 56-year-old Caucasian man presents with a 3 mm papule on the left nostril that has a pearly appearance, is skin-colored with smooth surfaces, and displays well-defined smooth borders. It has been present for 8 months, but it has become more noticeable in the past 3 months. The patient denies any other lesions with the same characteristics and wants it taken care of so it is not as bothersome. He denies weight loss, night sweats, or fevers; there have been no sleeping issues or recent changes in his appetite. Considering the most likely diagnosis, what diagnostic study is most crucial to confirm this pathology? A) Full-thickness biopsy B) Punch biopsy C) Excisional biopsy D) Observation only E) Mohs micrographic surgery

B) Punch biopsy Any lesion suspected of being malignant must be biopsied. Typically a suspected BCC would undergo a punch biopsy or shave biopsy to help confirm diagnosis. Punch biopsy is ideal for diagnostic reasons and provides better cosmetic results compared to shave biopsy. Mohs micrographic surgery (MMS) may be done after diagnosis is confirmed. MMS offers superior capability of histological analysis of tumor margins while permitting maximal conservation of tissue. MMS is particularly useful in high-risk anatomic sites and when there is a need for maximal preservation of tissue.

A 50-year-old woman has had a facial rash and a 10-year history of reddening of her face that comes and goes. On physical exam, you note erythema, telangiectasia, red papules, and tiny pustules on both cheeks. What is the most likely diagnosis? A) Perioral dermatitis B) Rosacea C) Seborrheic dermatitis D) Atopic dermatitis E) Lichen simplex

B) Rosacea The clinical picture is suggestive of rosacea. Rosacea is a chronic inflammatory condition of the facial pilosebaceous units. Peak incident occurs at ages 40-50; it predominantly affects women. Lesions develop in stages with a history of episodic reddening of the face. Skin lesions can appear as tiny papules and papulopustules, persistent erythema, and telangiectasia. Distribution is symmetric and primarily affects the face.

An 8-month-old male infant presents with rashes over the scalp and eyebrows. Physical examination shows a dry scaly crusting lesion over the scalp, eyebrows, and nape area. He is comfortable, so his mother presumed that it was not itchy at all. He has been breastfed up to this point, and he started solid food at about 5 months. There are no other signs or symptoms noted. Bowel movement and urination are normal. Developmental milestones are consistent with age. What is the most likely diagnosis? A) Atopic dermatitis B) Seborrheic dermatitis C) Psoriasis D) Candidiasis E) Lichen simplex chronicus

B) Seborrheic dermatitis The clinical picture is suggestive of seborrheic dermatitis, a chronic inflammatory disease common in the pediatric age group, especially during infancy and adolescence. Malassezia furfur has been implicated as a causative agent. It is clinically manifested as a diffused or focal scaling and crusting lesion seen over the scalp (called cradle cap), face, eyebrows, neck, axilla, retroauricular, and diaper areas. Treatment involves an anti-seborrheic shampoo, such as selenium sulfide, sulfuric acid, zinc pyrithione, and tar, for scalp lesions.

A mother brings in her 5-year-old son due to papular and pustular lesions on his face. A serous honey-colored fluid exudes from the lesions. You suspect impetigo. A Gram stain reveals spherical gram-positive arrangements in irregular grape-like clusters. What organism is most likely causing this patient's condition? A) Staphylococcus epidermidis B) Staphylococcus aureus C) Peptostreptococcus D) Streptococcus pneumoniae E) Haemophilus influenzae

B) Staphylococcus aureus The history and lab findings suggest the diagnosis of impetigo, in which Staphylococcus aureus is likely the causative organism. The most common causes of impetigo are usually more than likely Staphylococcus aureus, but also may be beta-hemolytic streptococcus group A.

A 20-year-old Caucasian male college student comes in with a complaint of hypopigmented patches that appeared gradually during the summer. He reports no history of unprotected sex. Scaly patches are present, but no pruritus. On examination, he has hypopigmented patches over the face and chest, but no vesicles or pustules. What is the most likely diagnosis? A) Leprosy B) Tinea versicolor C) Tinea cruris D) Vitiligo E) Tinea capitis

B) Tinea versicolor Tinea versicolor (Pityriasis versicolor) is a mild superficial infection of the skin. It is characterized by multiple usually asymptomatic scaly patches varying from white to brown in color. They are most frequently seen on the chest, neck, abdomen, and occasionally on the face. The condition is usually seen in young adults. Diagnosis of this condition is based on clinical findings. On microscopic examination of scraping from the lesion under a Woods lamp, yeast and short plump golden hyphae are seen. Treatment of T. versicolor involves topical therapy with selenium sulfide, imidazoles, and zinc pyrithione. Hypopigmented patches can be distinguished from vitiligo on the basis of appearance. Vitiligo usually presents as a loss and not just a lessening of pigmentation (as in T. versicolor), most commonly in the perioral region, wrists, and hands.

A woman presents with her 6-year-old adopted daughter due to excessive scratching of the scalp and ears. The woman states that she washes the girl's hair frequently, but it hasn't been helpful; the woman is very frustrated for her daughter. On examination of the scalp, excessive excoriations are noted on the posterior neck and postauricular regions bilaterally. No cervical lymphadenopathy is noted. Nits are also observed on the shaft of the hair. What is the appropriate treatment for this patient? A) Remove all household pets. B) Treat with permethrin. C) Treat with topical steroid. D) Treat with oral antibiotics. E) Treat with oral antifungals.

B) Treat with permethrin. Permethrin is the most common treatment for lice. The use of a fine tooth comb at least on a weekly basis helps with the removal of nits.

A 19-year-old man presents with hair loss described as localized oval patches for the past month. Upon examination, the patches are sharply demarcated without tenderness, erythema, or scaling noted. What is the most likely diagnosis? A) Secondary syphilis B) Trichotillomania C) Alopecia areata D) Male-pattern baldness E) Tinea capitis

C) Alopecia areata The most likely diagnosis is alopecia areata, as it typically occurs in children and young adults and presents as oval or round sharply demarcated patches of hair loss. Secondary syphilis typically presents with a moth-eaten appearance of hair loss. Trichotillomania (hair pulling) occurs most often in children and the hair loss is irregular and sporadic.

A 12-year-old boy presents with itching and redness between his toes. The mother notes that this is his second visit in 2 weeks, adding that her son had the same symptoms previously. She states that the child was prescribed an antifungal cream on the previous visit. They still have cream left. On examination, the interdigital spaces are macerated and erythematous. What is the most appropriate management for this case? A) Prescribe an antibiotic cream and reassure the mother. B) Prescribe an antibiotic cream and an oral antibiotic drug. C) Continue the antifungal cream and give health education advice. D) Continue the antifungal cream and prescribe a systemic antifungal drug. E) Prescribe a steroid cream.

C) Continue the antifungal cream and give health education advice. Continuing the antifungal cream and giving health education advice about the nature of the disease and how laundering the occlusive footwear will prevent relapse. Also, tinea pedis often recurs because the patient stops the medication as soon as the symptoms stop. Educate the patient to keep using the medication until the entire tube is empty. Factors that lead to moist skin (e.g., prolonged sweating in hot, humid, tropical environments; prolonged use of closed shoes) result in complications (e.g., hyperhidrosis, maceration) that make the skin subject to fungal infection. The mode of transmission is person-to-person, and activities such as swimming and communal bathing (keeping feet wet for a long time) increase the risk of infection.

A 35-year-old man presents with a 2-week history of recurrent swollen painful lips and a rash primarily affecting the arms and hands. His first episode occurred while in jail 6 months ago. He has had two additional episodes since then. He was treated with oral steroids each time, which improved his symptoms, but symptoms always returned. On examination, you notice several targetoid lesions on the dorsal hands and forearms, with darkening, swelling, and peeling of the lips. What additional information should you ask for to properly manage this patient? A) Any recent changes in personal hygiene products? B) Are there any pets at home? C) Have you ever had fever blisters, cold sores, or genital herpes? D) Were you working outside before onset of the rash? E) Any changes to diet before the onset of rash?

C) Have you ever had fever blisters, cold sores, or genital herpes? This patient's lesions are indicative of erythema multiforme, most commonly caused by the herpes simplex virus (which typically causes fever blisters, cold sores, or genital herpes). Recurrent cases of erythema multiforme often require long-term antiviral therapy.

A 5-year-old boy has three honey-colored crusted lesions with surrounding erythema on his legs. The swabs taken from the lesions were sent to the microbiology laboratory. The results show yellow colonies grown on blood agar with hemolysis. The colonies are coagulase-positive and mannitol-positive. What is the most likely diagnosis? A) Molluscum contagiosum B) Varicella zoster C) Impetigo D) Herpes zoster E) Erythema infectiosum

C) Impetigo The case described here is impetigo, a superficial skin infection common in children. The arms, legs, and face are more susceptible to impetigo than unexposed areas. Lesions vary from pea-sized vesicopustules to large ringworm-like lesions. They can start as maculopapules and rapidly progress to vesicopustules. The pustules enlarge and form a thick crust. Impetigo is classically described as honey-colored or golden crusted lesions.

A 21-year-old woman presents with a 3-month history of a black mole on her right calf. She tells you that the lesion is enlarging and expanding. It began to itch about 3 weeks ago, and it has bled 2 times. She has no significant past medical history. She works as a model, occasionally using a tanning booth. There is no family history of skin cancer. Exam is significant for fair complexion. There is a dark brown-black nodule on the right calf 1 cm in diameter with a tiny area of crusting. There are no hairs. The nodule is asymmetrical, with a sharply demarcated border; the color is uniform, and the elevation is regular. There is a narrow (1-2 mm) rim of erythema. There is no lymphadenopathy. What is the most likely diagnosis? A) Acral lentiginous melanoma B) Lentigo maligna melanoma C) Nodular melanoma D) Spitz nevus E) Dysplastic nevus

C) Nodular melanoma The sudden appearance of a black lesion on a fair-skinned woman's leg characterized by rapid growth, itching, and bleeding is highly suggestive of melanoma. Her history of sunbathing, and fair skin (more susceptible to burning) support the diagnosis. There are four main types of melanoma: - Acral lentiginous melanoma is the rarest of all melanomas, but the most common type in the African American and Asian populations. Lesions typically appear on the palms, soles, or under the nails. - Lentigo maligna melanoma is an uncommon type of melanoma that occurs most often in elderly individuals. It arises from a slow-growing precancerous condition called a lentigo maligna. - Nodular melanoma (NM) is the second most common type of melanoma and is the most aggressive of all melanoma skin cancers. It grows deep and quickly; it usually looks like a black bump but can be other colors. It is found most often on parts of the body that get a lot of sun exposure, such as the legs, torso, arms, and head. - Superficial spreading melanoma is the most common type of melanoma. It usually develops slowly and spreads out across the surface of the skin.

A 4-year-old Caucasian boy is seen in the outpatient clinic with a 3-week history of generalized rash. Pruritus was minimal; it has resolved, and he has not had a fever. The mother noted that the rash began as a single lesion on the abdomen that grew in size as the rash progressed elsewhere. It is now the largest lesion present. Examination revealed an otherwise well and afebrile child with a generalized rash consisting of scaly reddish-pink plaques concentrated on the trunk in a Christmas tree pattern with the single largest lesion at the abdomen. What is the optimal treatment? A) Coal tar application B) High dose oral prednisone C) Observation D) Topical clotrimazole E) Topical hydrocortisone

C) Observation Pityriasis rosea is a benign self-limited rash frequently seen in childhood. It typically begins with a single oval-shaped reddish-pink plaque on the torso that becomes scaly (herald patch), followed by similar lesions concentrated on the trunk in a pine/Christmas tree distribution. Treatment is aimed at pruritus, if present.

An 18-year-old man presents with multiple painful vesicles on an erythematous base on the right side of his lower lip. He experienced similar symptoms a month ago with an associated sore throat. He has an oral temperature of 101°F and positive tender cervical lymphadenopathy. What is the most appropriate clinical intervention? A) Oral amoxicillin/clavulanic acid for 10 days B) Punch biopsy of 1 of the lesions C) Oral valacyclovir D) IV acyclovir E) Tzanck preparation from the base of a lesion

C) Oral valacyclovir Mucocutaneous lesions of herpes simplex virus (HSV) can be treated with oral valacyclovir, famciclovir, or acyclovir to help clear the lesions. If outbreaks become frequent and bothersome, chronic suppressive therapy can be discussed with this patient. Intravenous acyclovir is reserved for the treatment for HSV encephalitis.

A 12-year-old girl presents with a 1-week history of a rash on her trunk. The patient has not been ill or exposed to anyone ill. On examination, there are scattered lesions on her trunk; they look like they form a Christmas tree. The girl states that the lesions are itchy at times, but they are generally not bothersome. What is the most likely diagnosis? A) Tinea corporis B) Seborrheic dermatitis C) Pityriasis rosea D) Tinea versicolor E) Viral exanthem

C) Pityriasis rosea Pityriasis rosea, most common in children and young adults, is a papulosquamous eruption which typically starts with a single lesion or spot referred to as the "herald patch" on the trunk. A generalized exanthem progresses from the herald patch with symmetric macules occurring along cleavage lines of the back, generally forming in the shape of a Christmas tree.

A 26-year-old Black male patient presents with a rash on the back. He first noticed the rash 3 weeks ago. He describes small, whitish, non-painful upper back lesions that do not itch. There is no significant past medical history; there are no known drug or food allergies; he is not taking any medications. On physical examination, there are several small hypopigmented macules that coalesce on the upper third of the back. Fine scaling is produced on scratching. The remainder of the physical examination is unremarkable. What is the most appropriate next step in the management of this patient? A) Obtain a fungal culture from the lesion. B) Perform a skin biopsy. C) Scrape lesions and KOH stain. D) Start on oral terbinafine. E) Start on oral griseofulvin.

C) Scrape lesions and KOH stain. his presentation is consistent with tinea versicolor. Tinea (or pityriasis) versicolor is a fungal infection caused by Malassezia furfur. The lesions present as small discrete macules or papules that tend to be darker than the surrounding skin in light-skinned patients and hypopigmented in patients with dark skin. They often coalesce to form large patches of various colors ranging from white to tan ("versicolor"). Tinea versicolor most commonly involves the upper trunk, but the arms, axillae, abdomen, and groin may also be affected. To confirm the diagnosis, a KOH preparation of scrapings from the lesions should be done, which can demonstrate pseudohyphae and spores resembling spaghetti and meatballs.

A 17-year-old girl presents to the clinic due to chronic fatigue. Her past medical history is unremarkable. There is no history of surgeries. Review of systems reveals heavy monthly menses since menarche at age 13. She admits to using more than 20 tampons on each of the heaviest 3 days of her menstrual cycle. Her last menstrual cycle commenced 1 week ago. There are no recent medications. Exam is within normal limits, with no vaginal discharge. Labs: pregnancy test negative; cervical cultures negative; thyroid studies within normal limits; Hb 10 g/dL, WBC 9000/μL, platelet count 250 x 103/μL. Peripheral blood smear is consistent with microcytic hypochromic anemia. Prothrombin time, partial thromboplastin time (PT, PTT), and fibrinogen are normal. Bleeding time is prolonged. What is the most likely diagnosis? A) Endometriosis B) Ectopic pregnancy C) Von Willebrand disease D) Disseminated intravascular coagulation E) Hemophilia A

C) Von Willebrand disease Approximately 20% of adolescent menorrhagia is caused by coagulation disorders. Von Willebrand disease (VWB disease) is an autosomal dominant disorder that affects platelet adhesion and fibrin clot formation. A bleeding time outside of reference range may suggest a hemostasis defect but is not diagnostic. The platelet function analyzer (PFA-100) is a relatively new in vitro measure of time required to form a platelet plug that allows more rapid evaluation and has more sensitivity than bleeding time. The clinical presentations of von Willebrand disease are variable and include a positive patient or family history of mucosal bleeding, epistaxis, gastrointestinal hemorrhage, easy bruising with ecchymoses, and (if severe) hemarthrosis.

An 18-year-old woman presents with chronic fatigue and menorrhagia. Menorrhagia has been present since her first menstrual cycle, but it has recently become worse; she sometimes uses 20 tampons per day. About a year ago, she started using contraceptive pills but is now considering stopping using them because of migraine-like headaches. Her headaches are sometimes so severe that she has to take aspirin or other painkillers several times a day. The rest of her past medical history is unremarkable. Physical examination reveals pale skin and mucosa, pulse rate of 100 beats per minute, and a systolic ejection murmur 1/3 intensity over the precordium. Laboratory findings include white blood count 9 K, hemoglobin 10, platelet count 250 K, normal prothrombin time, slightly prolonged partial thromboplastin time, and normal fibrinogen. Her bleeding time is prolonged. Blood smear shows microcytic hypochromic anemia. What is the most likely diagnosis? A) Endometriosis B) Ventricular septal defect C) Von Willebrand disease D) Hemolytic uremic syndrome E) Hemophilia A

C) Von Willebrand disease The cause of her fatigue is most probably anemia due to the blood loss. Having platelet-type of bleeding with normal PT and fibrinogen and prolonged PTT and bleeding time, she most likely has von Willebrand disease. Von Willebrand disease is the most common hereditary coagulation abnormality in humans, although it can also be acquired. Von Willebrand factor, which is deficient in this disease, is critical to the initial stages of blood clotting. Aspirin and many of the drugs used for pain can aggravate bleeding because they interfere with platelet function, but patients with von Willebrand disease can take acetaminophen for pain relief, as it does not inhibit platelet function.

A 20-year-old man with a past medical history of moderate acne has undergone 1 month of second-line acne therapy. He now presents with skin that looks worse; including more inflammation and the development of cysts. What is the most appropriate next step? A) Attempt a different second-line medication. B) Perform skin biopsies. C) Perform blood cultures. D) Add oral isotretinoin after stopping medication for 2 weeks. E) Add emollient cream and a sulfur-based cleanser.

D) Add oral isotretinoin after stopping medication for 2 weeks. Systemic treatment with isotretinoin is indicated for patients with cystic acne or with acne that has not responded to conventional therapy. For severe acne, the medications are continued, not discontinued.

A 72-year-old man—well known to your practice—presents with a severely itchy rash. His medical history includes Parkinson's disease for the past 10 years. At first, he thought the rash was just eczema, but the areas have progressed to significant hives, and itching has substantially worsened. On examination, you note multiple bullae that are 1-3 cm in size; they are tense, and they appear on an erythematous base. The bullae are noted to be located on the patient's trunk and the bilateral axillary and inguinal folds. What is considered the cornerstone of clinical intervention for this patient? A) Dapsone B) Azathioprine C) Mycophenolate mofetil D) Corticosteroids E) Methotrexate

D) Corticosteroids Corticosteroids, whether topical or systemic, are considered the cornerstone of therapy for bullous pemphigoid (BP). A topical corticosteroid (high potency) is considered the first-line agent. Significant adverse reactions can occur in the elderly population with long-term systemic corticosteroid use, so exercise great caution.

A 35-year-old woman notices a change in the appearance of a mole on her neck. Physical examination reveals that the lesion is an irregular nodular superficial mass with a variegated appearance. Biopsy demonstrates a primary malignant tumor. What characteristic of the malignant skin lesion is most predictive of the patient's long-term prognosis? A) Sharpness of border B) Diameter C) Color Variation D) Depth E) Asymmetry

D) Depth The lesion is a malignant melanoma. Melanomas can develop either de novo or in an existing mole. Sunlight exposure is a significant risk factor, and fair-skinned individuals are at increased risk of developing melanoma. The most significant factor for long-term prognosis is the depth of the lesion since the superficial dermis lies about 1 mm under the skin surface; penetration to this depth is associated with a much higher incidence of metastasis than is seen with a more superficial location.

A 62-year-old man who is well known to you presents with a severely itchy rash. The patient's medical history includes Parkinson's disease for the past decade. The patient felt the rash was just eczema at first, but the areas have progressed to significant hives; the itching has become far worse. On examination, you note multiple bullae that are 1 to 3 cm in size; they are tense and appear on an erythematous base. The bullae are noted to be located on the patient's trunk as well as the bilateral axillary and inguinal folds. What diagnostic study would be the gold standard to confirm your suspected diagnosis? A) Hematoxylin staining B) Enzyme-linked immunosorbent assay C) Eosin staining D) Direct immunofluorescence E) Detection of viral antibodies

D) Direct immunofluorescence Diagnosis is made by the gold standard, which is a skin biopsy for direct immunofluorescence (DIF). Enzyme-linked immunosorbent assay (ELISA)—which requires a collection of at least 5 mL of venous blood—also supports the diagnosis, but it is not the gold standard. Hematoxylin and eosin staining are also conducted via a skin biopsy but are not the gold standard. Detection of viral antibodies is not appropriate in the case of BP, as this is an autoimmune process.

A 5-year-old girl presents with a rash. The girl's mother states that she took the child to an urgent care center over the previous weekend; the patient was diagnosed with a urinary tract infection. The child was started on a 7-day course of sulfamethoxazole/trimethoprim and currently only has one more dose to take. The mother states the child has never taken this type of medication before. The rash in question was first noticeable 2 days ago; it has spread, worsened, and intensified, prompting the mother to bring the child in today. She denies any recent fevers, irritability, itching, or other significant symptoms. Her previous UTI symptoms have resolved. On physical examination, you note scattered lesions on the child. Each lesion appears to have three concentric circles of color change. Making note of the characteristic target lesions this patient displays, what treatment should be recommended? A) Continue sulfamethoxazole/trimethoprim; begin acyclovir. B) Discontinue sulfamethoxazole/trimethoprim; begin topical diphenhydramine. C) Continue sulfamethoxazole/trimethoprim; begin azithromycin. D) Discontinue sulfamethoxazole/trimethoprim; monitor symptoms. E) Discontinue sulfamethoxazole/trimethoprim; begin cetirizine.

D) Discontinue sulfamethoxazole/trimethoprim; monitor symptoms. This patient has a classic example of uncomplicated erythema multiforme (EM). EM typically begins as papules that later develop a dark center and then evolve into lesions with central bluish discoloration or blisters. They then will have the characteristic target lesions (iris lesions), which appear with 3 concentric circles of color change. Causes may include herpes simplex virus, various drugs (most commonly sulfonamides), and Mycoplasma infections. The patient is otherwise asymptomatic. For these reasons, discontinuation of the sulfamethoxazole/trimethoprim and supportive symptomatic care is the appropriate treatment.

A 46-year-old woman underwent elective cholecystectomy. The attending nurse noted mild bleeding at the site of IV line and the incision site during dressing. The patient also reported bleeding from the gums and nose. Coagulation profiles revealed prolongation of aPTT, PT, and TT; decreased fibrinogen level; and increased levels of fibrinogen degradation product (FDP). Platelet count was also decreased. The patient was not experiencing any bleeding disorder before her hospitalization. What is the most likely cause of this patient's bleeding tendency? A) Deficiency of clotting factors of the intrinsic pathway B) Deficiency of clotting factors of the extrinsic pathway C) Platelet functional defect D) Disseminated intravascular coagulation E) Underlying liver disease

D) Disseminated intravascular coagulation Prolongation of aPTT, PT, and TT; decreased fibrinogen level; increased levels of FDP; and decreased platelet count indicate disseminated intravascular coagulation (DIC). DIC is an acquired syndrome characterized by bleeding from multiple sites, ecchymoses, mucosal bleeding, and depletion of platelets and clotting factors in the blood. The causes of DIC include infections (bacteria and their toxins, fungi, viruses, rickettsiae), obstetric and gynecological causes (such as abruptio placentae, abortions, eclampsia, amniotic fluid embolism), hemorrhagic shock, malignancy, snake venom, trauma, and transfusions.

A mother presents with her 5-year-old Caucasian son; he has a significantly swollen right knee. She states that her son has a blood coagulation disorder and frequently bleeds into his joints when he sustains any injury. His past medical history includes the use of the blood product cryoprecipitate or factor VIII concentrates for treatment for his disorder. What is the most likely diagnosis? A) Coagulation disorder due to liver disease B) Hemophilia B C) Von Willebrand disease D) Hemophilia A E) DIC with thrombosis

D) Hemophilia A In addition to general supportive therapy, a cryoprecipitate or factor VIII concentrates are recommended for treatment of hemophilia A, an X-linked disorder that results in deficiency of factor VIII. The diagnostic characteristic is a decrease in VIII:C activity while VIII:R level is normal. Patients who bleed frequently, even without discernible trauma, usually show <1% factor VIII activity.

A 43-year-old woman presents with 4 days of fever and cough. She is diagnosed with right lobar pneumonia with mild pleural effusion and is admitted to the hospital for IV antibiotics and hydration. Past medical history includes hypertension, systemic lupus erythematosus, and arthritis. On day 2 of hospitalization, she is afebrile but still has a productive cough and shortness of breath. She reports left arm pain and swelling, and her physician is concerned about a possible upper extremity thrombosis. She is given a bolus of IV heparin and started on a heparin infusion. 5 days later, her labs show Hb 12 g/dL, WBC 11,000, and platelet count 56 micro/L (down from 250 on admission). Her EKG is normal sinus rhythm, and CXR show decreased consolidation with a resolving pleural effusion. What is the most likely diagnosis? A) Lupus anticoagulant B) Oral contraceptive-induced thrombosis C) Trousseau's syndrome D) Heparin-induced thrombocytopenia E) Paroxysmal nocturnal hemoglobinuria (PNH)

D) Heparin-induced thrombocytopenia Heparin-induced thrombocytopenia is a life-threatening complication of heparin therapy, occurring 5-10 days after heparin treatment has started, resulting from the formation of antibodies against the heparin-platelet factor 4 complex. Heparin is an anticoagulant used for the treatment of deep vein thrombosis, and the principle side effect is bleeding. Heparin-induced thrombocytopenia is associated with thrombocytopenia and thrombus formation. Treatment involves prompt discontinuation of heparin.

A 3-day-old male newborn starts to have mild epistaxis after vaginal delivery at home. The mother is a 38-year-old G2P2 who had diet-controlled gestational diabetes. She took a prenatal vitamin and iron supplement. Active labor lasted 3 hours. The midwife who examined the newborn after the delivery declared the newborn healthy. Since the delivery, the mother has been exclusively breastfeeding. The baby is eating every 1-2 hours and has had several wet diapers and 3 stools. What would be the most definitive treatment for this newborn's epistaxis? A) Fresh frozen plasma B) Whole blood transfusion C) Direct pressure to nares D) Intravenous vitamin K E) Intravenous vitamin C

D) Intravenous vitamin K This baby is at risk for hemorrhagic disease of the newborn because he was born at home and may not have had immediate and routine medical care. A decrease in factors II, VII, IX, and X normally occurs in all newborns by 48-72 hours. There is a gradual return to birth levels by 7-10 days of life. Routinely in a hospital setting, an intramuscular dose of vitamin K immediately after birth helps prevent hemorrhagic disease of the newborn. The disease is treated with an intravenous infusion of vitamin K, with improvement in coagulation defects within a few hours. Pressure and chemocautery will not correct the coagulation factors. Plasma and blood transfusions may be needed if the baby has a severe form of vitamin K deficiency and his PT fails to improve, or if the bleed is severe.

A 3-year-old girl presents with a 2-week history of a pruritic erythematous excoriated rash. Her past medical history is unremarkable. Her only medications include a topical steroid ointment and oral diphenhydramine. She has no known allergies. She lives on a farm on the outskirts of her town. She does not attend daycare and lives with three older siblings and her parents. There are cats and dogs in the house, which appear to be in good health. Her physical exam is significant for small red papules in her interdigital spaces, wrist flexors, anterior axillary folds, and forearms. Scattered red-brown nodules are found in her axillary region. What diagnostic study would confirm the diagnosis? A) Wood lamp examination B) Skin biopsy C) Culture of epidermal scrapings D) Microscopic examination of skin scrapings E) Potassium hydroxide prep of skin scrapings

D) Microscopic examination of skin scrapings Scabies is caused by the burrowing and release of toxic substances by the adult female mite Sarcoptes scabiei var. hominis. Clinical manifestations include an intensely pruritic papular rash characterized by thread-like burrows. The papules may be excoriated, scaly, or crusted. Infants with scabies may not manifest the classic burrows but may present with pustules or bullae. Older children, adolescents, and adults usually present with papules and burrows in the interdigital areas, wrist flexors, axillary regions, buttocks, ankles, and groin. Palms and soles are generally spared. Occasionally nodules are found, most notably in the axilla, groin, and genitalia. The diagnosis can be made clinically but can be confirmed with a microscopic examination of skin scrapings, which can reveal mites or ova in the epidermal scrapings.

A 15-year-old boy presents for follow-up for acne vulgaris. He has been using benzoyl peroxide and retinoic acid for the past 4 months. He returns for a re-evaluation, as his acne appears to have worsened. He states his diet has not changed significantly, and his past medical history is unremarkable. His mother had significant acne as an adolescent. Physical examination reveals large papules and pustules on the forehead, cheeks, chin, and upper back. No nodulocystic cystic lesions are noted. What is the most appropriate next step in management? A) Intralesional steroid injections B) Abstinence from chocolate C) Increased skin washing D) Oral doxycycline E) Oral isotretinoin

D) Oral doxycycline Treatment of mild to moderate acne consists of the topical preparations benzoyl peroxide and retinoic acid in varying strengths. Topical antibiotics may be helpful as adjuncts in decreasing the growth of P. acnes. They are most effective if used in conjunction with the other topical preparations. Patients who do not tolerate or who have not responded to topical medications are prescribed oral antibiotics, including doxycycline, tetracycline, and clindamycin. These patients typically have moderate to severe acne with papules, pustules, nodules, and cysts.

An 18-year-old college student presents with a bright red rash on her left cheek area that has worsened since yesterday when it first appeared. It is now becoming more tender and she developed a temperature elevation of 100.2°F taken at home. She denies any new soaps or facial creams and wears occasional make-up. She denies any ill contacts. Vital signs are blood pressure of 110/72 mmHg, heart rate 86 bpm regular, respirations 18/min, and temperature of 100.4 °F. Your most likely diagnosis is erysipelas. She denies any medication allergies. What is the most important next step in the management of this patient? A) CBC with differential, AST, and ALT B) Intravenous penicillin G for 48 hours, then penicillin VK 250 mg 4 times daily for 7 days C) Intravenous erythromycin for 48 hours, then erythromycin 250 mg orally 4 times daily for 7 days D) Penicillin VK 250 mg 4 times daily for 7 days E) Blood cultures

D) Penicillin VK 250 mg 4 times daily for 7 days Erysipelas is a cellulitis most often caused by beta-hemolytic streptococci; it causes a bright red painful area typically seen on the cheek often near the angle of the nose. If this disease is not treated promptly, it can become systemically toxic and may result in death, especially in the very young and very old. In most cases, oral antibiotics are appropriate. In patients with diabetes or elderly patients, IV antibiotics active against beta-hemolytic streptococci and staphylococcus for the first 48 hours are indicated, followed by oral administration of similar drug for 1 week. If it is a mild case, IV antibiotics are not always indicated. Since this patient is young, hemodynamically stable, and fever is low at 100.4°F, oral antibiotics with penicillin VK 250 mg 4 times daily for 7 days is the best option.

A 40-year-old man presents with burning and pain of his oral cavity; the burning and pain have been associated with a pruritic rash of the flexor aspect of his left wrist. He denies a history of smoking, drinking, or recreational drug use. The physical exam is remarkable for violaceous shiny polygonal papules arranged in lines and circles on his wrist. These papules range from 1 mm to 1 cm in diameter, and they have fine white lines on them. In the oral cavity, a reticular white lacy pattern is visualized. What education can you provide this patient about their diagnosis? A) Imaging study modalities are required for diagnosis. B) Antifungal pharmacotherapy is typically curative. C) The oral lesion is premalignant, caused by carcinogen exposure. D) This immune response is associated with hepatitis C. E) The most common cause is nutritional deficiency.

D) This immune response is associated with hepatitis C. This patient most likely has lichen planus with cutaneous and oral involvement. It is an inflammatory mucocutaneous condition that usually exhibits a distinctive morphology; it is associated with hepatitis C virus infection, chronic active hepatitis, and primary biliary cirrhosis. The classic appearance of skin lesions includes violaceous polygonal flat-topped papules and plaques, commonly occurring at the wrist. White lines found within papules (Wickham's striae) may also be found.

A 10-year-old boy presents with a 1-week history of a rash on his scalp. His mother states that the boy has been scratching his head often, and she notes that there are areas where his hair appears to have fallen out. She attempted to treat it with over-the-counter preparations, but his condition has not improved. The boy is active and otherwise healthy. The rash appears as erythematous, circular, scaly patches. There are areas where the hairs have become brittle and broken off. A scraping of one of the patches is placed in potassium hydroxide solution and shows hyphae. What is the most likely diagnosis? A) Vitiligo B) Tinea versicolor C) Psoriasis D) Tinea capitis E) Seborrheic dermatitis

D) Tinea capitis Tinea capitis, also known as ringworm, is a fungal skin infection that is more common in children. It is contagious and can be difficult to rid the patient of the infection. It is called ringworm due to the appearance of the infection on the skin; the lesions produced are ring-shaped and were once thought to be caused by a worm. It is caused by a fungus from the species Trichophyton and Microsporum. The lesions usually begin as round, often reddened, papules on the scalp. Over the course of a few days, the papules become scaly and coalesce to form a ring-like shape. The hair often breaks off in the affected area, making the infection more noticeable. There can be itching, swelling, and occasionally a purulent discharge. Diagnosis can be confirmed by microscopic analysis. A scraping of the area placed in potassium hydroxide solution will show hyphae if a fungal infection is present. Once this has been established, treatment can begin.

A 35-year-old woman presents with intensely pruritic red papules over the anterior wrists. On close examination, the papules are shiny; they have a flat surface and there is occasional central umbilication. A red plaque is seen along the scratch line at the anterior forearm. What is the best initial therapy for the patient? A) Oral corticosteroid or immunosuppressant B) Anti-retroviral agents C) UVA phototherapy D) Topical corticosteroid E) Gluten-free diet and dapsone

D) Topical corticosteroid Lichen planus is characterized by flat-topped pruritic red-to-violaceous papules or plaques, mostly on the wrists. Lesions are polygonal with occasional central umbilication. As with psoriasis, the classic Koebner phenomenon also may be present in lichen planus. Most cases are idiopathic, but studies have shown an association with hepatitis C infection. The best initial therapy for localized lichen planus is a potent topical corticosteroid.

A 70-year-old man on vacation in the US presents for what appears to be suspicious skin lesion on his cheek. He has had a longstanding discolored patch; it has recently enlarged in size, and there is crusting. A biopsy confirms your suspected diagnosis. After undergoing treatment, he wants to take measures to prevent a recurrence. What is the most appropriate advice for prevention of recurrence? A) Use indoor tanning salons. B) Strictly avoid damaging UV-B rays. C) Use SPF 50 sunscreen or higher. D) Wear protective clothing and avoid midday sun. E) Use zinc oxide paste.

D) Wear protective clothing and avoid midday sun. The use of protective clothing and avoidance of midday sun is the single best measure to avoid exposure to UV rays. Darker clothing, wide-brimmed hats, and full sleeves are helpful.

A 67-year-old man was cleaning out his garage and noticed a "bug" crawling on his leg. The bug bit him before the patient killed it. He discarded it and went about his business. 2 days later, he presents with pain, itching, and swelling of the affected leg. The bug had a violin-shaped pattern on its back. Based on the patient's symptoms and description, what was this "bug"? A) Scorpion B) Black widow spider C) Wasp D) Mosquito E) Brown recluse spider

E) Brown recluse spider Based on the description and the symptoms, the referred to "bug" is a brown recluse spider. The brown recluse is one of only about four spiders capable of being dangerous to humans. They are native to the midwestern and southeastern sections of the United States. The bite from one can result in death if treatment is not given. The brown recluse spider can be recognized by the "violin" pattern found on its back. They are usually dark brown in color and have dark brown to black colored legs. They usually do not attack unless frightened or when they touch the skin of an animal or human. They can be found in closets, basements, sleeping bags, woodpiles, or other warm and dry places.

A 30-year-old woman presents with a 2-week history of itchy pimples on her wrist. On examination, there are violaceous papules with a network of gray lines on their surface; they are found on the medial aspect of her right wrist. What is the most likely diagnosis? A) Asteatotic eczema B) Stasis dermatitis C) Contact dermatitis D) Lichen simplex chronicus E) Lichen planus

E) Lichen planus Lichen planus is characterized by pruritic, polygonal, flat-topped, violet papules that have a network of gray lines (Wickham's striae) on the surface. They commonly develop on the wrists, legs, and genitalia. Management includes topical glucocorticoids, though many patients have spontaneous remissions.

A 73-year-old male presents reporting that his toenails are thick, hard to cut, discolored, and dystrophic. A KOH culture confirmed a fungal infection. What is the most likely diagnosis? A) Onychocryptosis B) Onychauxis C) Onychogryphosis D) Onycholysis E) Onychomycosis

E) Onychomycosis The term used for ingrown nail is onychocryptosis. Onychauxis is used to define a thickened overgrown nail. A hooked or incurvated nail is defined by onychogryphosis. Onycholysis is the loosening or separation of all or part of the nail from the nail bed.

A 2-year-old boy is brought to your office by his mother after she noticed that he often scratches his head. She also notes patchy loss of hair on the top of his head. She has been sending him to a daycare center for the past 2 months. On examination, you note patchy loss of hair in the right parietal area and another area of "black dot" alopecia about 4 cm lateral to it. The area of hair loss shows a grayish ring-shaped scaly lesion. A KOH preparation demonstrates branching hyphae and spores. What is the best treatment for this condition? A) Topical fluconazole B) Oral prednisolone C) Topical ciclopirox D) Topical hydrocortisone E) Oral griseofulvin

E) Oral griseofulvin Oral therapy is necessary for tinea capitis, as topical therapy is ineffective. Griseofulvin is considered the gold standard, although it requires 6-12 weeks of therapy and relapse may occur. Other options are oral ketoconazole (risk of hepatotoxicity), itraconazole, fluconazole, and terbinafine. Adjunctive therapy with selenium sulfide or ketoconazole shampoo may reduce viable fungal shedding and spores.

A 28-year-old man presents with a rash. The lesions, which are mildly pruritic, are located on his arms and legs. They have been present for about 3 days without change or resolution. He has tried over-the-counter anti-itch creams, but they have been ineffective. The patient reports that he was seen approximately 1 week ago for some blister-like lesions on his penis. He was given an antiviral medicine, and those lesions resolved. He is wondering if he was misdiagnosed and if the two rashes are related. He admits to feeling some malaise over the last 2 weeks, but he is otherwise healthy. He denies fevers, unusual travel, medication use (except for as listed above), and known allergies. He has no known chronic conditions. On physical exam, vitals are normal; the patient is in no apparent distress. A pink-to-red papular rash is observed on the backs of the hands and feet and extensor surfaces of the arms and legs. The individual lesions are quite distinct; they have a red center, and they are surrounded by a pale ring and then another outer ring of red, inflamed tissue. The remainder of his physical exam is normal. What test will confirm the suspected diagnosis? A) Complete blood count (CBC) with differential B) Fungal culture C) Herpes culture D) Heterophile antibody E) Skin biopsy

E) Skin biopsy This patient is presenting with a target lesion rash; it is typical of erythema multiforme, which is a relatively common type IV hypersensitivity reaction. The confirmatory test is skin biopsy. In about 50% of cases of erythema multiforme, no cause is identified. Other causes are infection and medications. When a cause is identified, recent herpes simplex virus (HSV) infection is the most common. In this patient's case, he likely was appropriately diagnosed and treated for his HSV infection, then developed the erythema multiforme rash. Erythema multiforme is an acute self-limited condition and can range in severity from a rash and mild malaise and pruritus (erythema multiforme minor) to a much more severe condition, involving mucosal surfaces and possible desquamation with erythema multiforme major.

A 68-year-old Irish farmer presents for his annual physical examination. He smokes 10 cigarettes per day. He has no complaints, but an erythematous scaly non-tender nodule measuring 0.5 cm is noted on his left lower lip. There are no surrounding telangiectasias. The nodule is firm, ill-defined, and fixed to the underlying tissue. It does not blanch with pressure. What is the most likely diagnosis of this lesion? A) Hemangioma B) Benign nevus C) Actinic keratosis D) Basal cell carcinoma E) Squamous cell carcinoma

E) Squamous cell carcinoma The lesion described is characteristic of squamous cell carcinoma (SCC). The patient is of Celtic descent with an outdoor profession, which puts him at increased risk for developing this type of lesion. Actinic keratoses (AK) are precursors to SCC and are typically hyperkeratotic. It can be difficult to distinguish between AK and SCC clinically, but this lesion is firm and fixed to underlying structures. Basal cell carcinomas are also more common on sun-exposed areas, but they often have surrounding telangiectasias and a rolled border.

A 50-year-old woman presents with a 4-month history of white patches on her skin. The patches of discoloration easily burn when exposed to sun but are not painful. Physical exam reveals well demarcated white macules on her face, neck and hands. There is no erythema, crusting, or drainage. What is the most likely diagnosis? A) Melanoma B) Alopecia C) Psoriasis D) Melasma E) Vitiligo

E) Vitiligo This patient has vitiligo, the most common cause of depigmentation. It is most common in the teens and 20s, and the etiology is unknown in most patients. Patients present with well-demarcated white macules/patches that occur most commonly on the face, genitals, and hands. Diagnosis is typically made clinically but can be confirmed with biopsy. Treatment depends on the extent of disease but can include topical or systemic corticosteroids, topical calcineurin inhibitors, or phototherapy.