UWorld 4/19

Leukocyte adhesion deficiency involves decreased expression of the neutrophil cell-surface adhesion proteins, β-2 integrins. As a result, neutrophils are less adherent to the vascular endothelium and fail to migrate toward infected sites. There is delayed separation of the umbilical cord _____ (how long), omphalitis, and leukocytosis (unlike this patient, who has a normal white count and differential for his age).

>1 month

A 52-year-old man comes to the office due to right shoulder pain. He is an avid golfer but has been unable to play for the past 3 months due to the pain. Lately, it has started to interfere with his daily activities, such as getting dressed. An MRI shows thickening and calcification of the supraspinatus tendon. Which of the following shoulder actions is most likely to provoke pain in this patient? A. Abduction (%) B. Adduction (%) C. Extension (%) D. Flexion (%) E. Internal rotation (%)

A. Abduction (%) first 15 degrees of abduction are supraspinatus (Stop doing this Sarah!!)

A 52-year-old man comes to the emergency department (ED) due to 2 hours of burning substernal pain. Before coming to the ED, he took several tablets of antacid at home without any relief. The patient's other medical problems include hypertension and hyperlipidemia. His temperature is 36.7 C (98 F), blood pressure is 160/90 mm Hg, and pulse is 92/min. Cardiovascular examination shows normal S1 and S2 without any murmurs. There is no abdominal tenderness. ECG shows ST-segment depression in leads II, III, and aVF. Troponin is 0.06 ng/mL (normal <0.01 ng/mL). As part of this patient's treatment, enoxaparin therapy is initiated. This drug is expected to bind to which of the following substances in this patient's blood? A. Antithrombin III (%) B. Fibrin (%) C. Plasminogen (%) D. Protein C (%) E. Prothrombin (%)

A. Antithrombin III (%) This patient with chest pain, ST depressions, and mild troponin elevation appears to be experiencing a myocardial infarction. Enoxaparin is a form of low-molecular-weight heparin (LMWH) that, like heparin, functions by binding antithrombin III (AT III) via a pentasaccharide sequence. Once activated, AT III binds to factor Xa and stops factor Xa from converting prothrombin to thrombin. Less thrombin is produced, resulting in an anticoagulant effect. Unfractionated heparin has more molecules than LMWH, allowing it to bind factor Xa and thrombin; it is more effective than LMWH in inactivating thrombin.

A 64-year-old man dies suddenly while playing tennis. In the preceding months, he experienced fatigue and some exertional dyspnea. Autopsy is performed. The heart examination shows left ventricular septal thickness of 1.6 cm (normal: <1.1), posterior wall thickness of 1.6 cm (normal: <1.1), and an internal left ventricular diameter of 3.2 cm (normal: 3.5-5.9). No focal myocardial scarring is seen. Which of the following is the most likely cause of the cardiac findings seen in this individual? A. Aortic stenosis (%) B. Dilated cardiomyopathy (%) C. Mitral regurgitation (%) D. Obstructive coronary artery disease (%) E. Rheumatic mitral stenosis (%)

A. Aortic stenosis (%)

A 64-year-old smoker is evaluated for nagging right shoulder pain that radiates to the ipsilateral arm. The patient also has weakness in the right upper extremity. His symptoms started 2 months ago and have worsened progressively. On neurologic examination, the patient is awake, alert, oriented, and follows commands. He has partial right-sided ptosis with fully intact extraocular movements. His pupils are asymmetric in dim light with 2 mm on the right and 4 mm on the left, but both are reactive to light. The pupils become more symmetric in bright light. The right upper extremity has 3/5 strength and absent deep tendon reflexes. This patient's autonomic dysfunction is most likely a result of a lesion involving which of the following? A. Autonomic ganglia (%) B. Brainstem (%) C. Cerebral cortex (%) D. Spinal cord (%) E. Subcortical grey matter (%) F. Vagus nerve (%)

A. Autonomic ganglia (%) This patient's smoking history, upper limb pain/weakness, and ipsilateral ptosis and miosis are highly suggestive of a Pancoast tumor. Pancoast tumors are usually non-small cell lung cancers (eg, squamous cell carcinoma, adenocarcinoma) that arise near the superior sulcus (the groove produced by the subclavian artery). Clinical manifestations are determined by the extent of local spread. Compression and invasion of the brachial plexus can cause ipsilateral shoulder pain, upper limb paresthesias, and areflexic arm weakness. Involvement of the cervical sympathetic ganglia may lead to Horner's syndrome, which is characterized by ipsilateral: Partial ptosis (drooping of upper eyelid), due to denervation of the sympathetically controlled superior tarsal muscle of the upper eyelid. Miosis (constricted pupil), due to interruption of the sympathetic fibers to the dilator pupillae muscle, which leads to unopposed parasympathetic influence. Pupil asymmetry is more prominent when examined in dim light due to increased sympathetic activity exacerbating the defect. Anhidrosis (impaired sweating), due to loss of sympathetic innervation of the facial sweat glands. Horner's syndrome can result from disruption at any point along the sympathetic pathway to the eye. First order sympathetic neurons are located in the hypothalamus. Their axons descend through the brainstem to the C8-T2 segments of the spinal cord (ciliospinal center of Budge), where they synapse on second order neurons found in the intermediolateral cell column. Second order axons exit the spinal cord through the anterior nerve roots and white communicating rami to reach third order neurons located in the superior cervical ganglion. From here, postganglionic fibers travel along the carotid arteries to reach target tissues in the face and head.

A 53-year-old man comes to the emergency department due to progressively worsening shortness of breath, nonproductive cough, and low-grade fevers over the past 2 weeks. He has not had a runny nose or sore throat and does not recall any sick contacts. He received a lung transplant for idiopathic pulmonary fibrosis 4 months ago. His medications include immunosuppressants and trimethoprim-sulfamethoxazole. Temperature is 37.8 C (100 F). Chest x-ray reveals diffuse interstitial infiltrates bilaterally. A decrease in pulmonary function is noted on testing. A lung biopsy specimen is shown below. Which of the following best characterizes the organism most likely responsible for this patient's current condition? A. Enveloped double-stranded DNA virus (%) B. Enveloped single-stranded RNA virus (%) C. Filamentous gram-positive rods (%) D. Nonenveloped double-stranded DNA virus (%) E. Nonenveloped single-stranded RNA virus (%) F. Trophic and cystic fungal forms (%)

A. Enveloped double-stranded DNA virus (%) Transplant patients are at risk for a variety of unusual infections due to their immunocompromised state. Cytomegalovirus (CMV) is particularly common in patients with lung transplants (typically occurring within the first few months after transplant). Most but not all transplant centers practice universal prophylaxis for lung transplant recipients (eg, valganciclovir). CMV is an enveloped double-stranded DNA virus belonging to the Herpesviridae family. Major risk groups for infections include transplant patients, patients with HIV, and fetuses (congenital infections). CMV pneumonitis is the most common form of tissue-invasive CMV following lung transplantation; other organ-specific disease manifestions (eg, esophagitis, colitis, and retinitis) occur more frequently in patients with HIV. Biopsy findings consistent with CMV include enlarged cells with intranuclear and intracytoplasmic inclusions (viral particles); there is often a surrounding halo (owl's eye).

A 48-year-old woman comes to the office for follow-up of type 2 diabetes mellitus. She has had diabetes for 10 years with gradually worsening glycemic control despite taking multiple oral antidiabetic agents. Three months ago, the patient discontinued her oral medications (except for metformin) and started a daily injection of insulin glargine; she has had multiple visits with the diabetes educator since then to review injection technique and titrate up the dose. However, the patient reports a 4.5-kg (10-lb) weight gain since starting insulin. She says, "I feel like I need to eat more. If that's how insulin is going to be, then I don't want to continue it." Which of the following is the most appropriate response to this patient's statement? A. "Regular exercise can reduce insulin-induced weight gain. What are your current exercise habits?" (%) B. "Some patients eat more after starting insulin because they fear their sugar may drop. Have you noticed that happening to you?" (%) C. "Sometimes stress can increase your appetite. How are things in your life right now?" (%) D. "Unfortunately, although insulin controls diabetes, it can cause weight gain. But the benefits outweigh the side effects." (%)

B. "Some patients eat more after starting insulin because they fear their sugar may drop. Have you noticed that happening to you?" (%) Insulin therapy for diabetes mellitus commonly causes weight gain due to increased peripheral glucose uptake, increased adipose lipid deposition, and reduced renal glucose loss (due to normalization of blood glucose, which reduces the filtered glucose load). Behavioral factors, including snacking and less rigorous adherence to dietary recommendations, can also contribute. Weight gain is especially pronounced in patients with type 2 diabetes who typically have high circulating levels of insulin and preexisting obesity. This patient has experienced weight gain after initiating a long-acting insulin analogue (ie, insulin glargine). Insulin normally suppresses appetite, but this patient reports increased need to eat, which suggests that the weight gain may not be simply due to the metabolic effects of insulin. Specifically, this patient may be eating more to suppress feelings of hypoglycemia. To address this patient's insulin-induced weight gain, the clinician should obtain additional history to elicit the patient's perspective on appetite, recent changes in dietary patterns, and associated hypoglycemic symptoms. Once the causes are better understood, several strategies, including dietary modification and changes to the insulin regimen, can mitigate insulin-induced weight gain

An 82-year-old man is found unresponsive by his neighbor. The patient lives alone in his suburban home. When the neighbor went to check on him, the patient was on the floor and not answering any questions. His medical history is unknown. On arrival of emergency medical services, the patient is obtunded and responds only to painful stimuli. Supportive measures are begun, including endotracheal intubation, but the patient dies en route to the hospital. Autopsy reveals extensive atherosclerotic disease involving the coronary and internal carotid arteries. Histopathologic examination of the brain in the right middle cerebral artery territory shows neurons with intensely eosinophilic cytoplasm and nuclear fragmentation. Based on these findings, this patient's cerebral injury most likely occurred approximately how long ago? A. Less than an hour (%) B. 12-24 hours (%) C. 1-2 weeks (%) D. 2 months (%) E. 2 years (%)

B. 12-24 hours (%)

A 63-year-old woman comes to the office for a routine preventive examination. She has no significant medical problems and takes no medications. The patient consumes a balanced diet; gets regular exercise; and does not use tobacco, alcohol, or illicit drugs. She is up to date on breast, colon, cervical, and lipid screenings. Her physical examination findings are unremarkable. The patient expresses concern about wrinkles around her eyes that make her "look old." A decrease in which of the following is most likely responsible for this patient's complaint? A. Collagen cross-linking (%) B. Collagen fibril production (%) C. Collagenase synthesis (%) D. Elastin degradation (%) E. Proline hydroxylation (%)

B. Collagen fibril production (%) Multiple environmental factors, especially exposure to ultraviolet (UV) light, contribute to aging of the skin. UVB wavelengths are predominantly absorbed in the upper dermis and contribute to sunburn and increased risk of malignancy. UVA wavelengths penetrate deeper into skin and cause photoaging. UVA produces reactive oxygen species, which activate multiple inflammatory cell-surface receptors and nuclear transcription factors. This leads to decreased collagen fibril production, along with upregulation of matrix metalloproteinases (including collagenases) that subsequently degrade type I and III collagen and elastin (Choices C and D). Photoaging may be visible by age 30-35. Gradual thinning of the epidermis is seen, with reduction in subcutaneous fat, blood vessels, hair follicles, sweat ducts, and sebaceous glands. Rete ridges at the dermoepidermal junction become flattened. This loss of subcutaneous tissue causes the skin to become atrophic and more vulnerable to damage. In addition, there is increased crosslinking of collagen (Choice A), with deposition of collagen breakdown products. The atrophic dermis and increased collagen crosslinking, along with desiccation of the stratum corneum, produce the characteristic wrinkling of photoaged skin

A 15-year-old male suffers severe cardiomyopathy following an infective myocarditis from Coxsackie virus and is placed on the cardiac transplant list. Two weeks following his cardiac transplantation from a matched donor, he is suffering dyspnea on exertion. Extensive evaluation is undertaken in this patient including cardiac catheterization and endomyocardial biopsy. Which of the following findings is most consistent with acute graft rejection? A. Concentric coronary atherosclerosis (%) B. Dense interstitial lymphocytic infiltrate (%) C. Perivascular infiltrate with abundant eosinophils (%) D. Patchy necrosis with granulation tissue (%) E. Scant inflammatory cells and interstitial fibrosis (%)

B. Dense interstitial lymphocytic infiltrate (%)

A 13-year-old boy comes to the office for a postoperative follow-up visit. He was seen in the emergency department 3 weeks earlier with acute abdominal pain and was found to have acute appendicitis. The patient underwent urgent appendectomy without any apparent immediate complications and was released home. Several days later, he started having burning pain at the surgical scar radiating to the suprapubic region but otherwise feels well. Examination shows a healed surgical incision centered over McBurney point. There is a loss of sensation over the right suprapubic area. The cremasteric reflex is normal. Which of the following nerves is most likely injured in this patient? A. Femoral (%) B. Genitofemoral (%) C. Iliohypogastric (%) D. Ilioinguinal (%) E. Lateral femoral cutaneous (%) F. Obturator (%)

C. Iliohypogastric (%) The iliohypogastric nerve arises from the L1 nerve root, emerges from the lateral border of the upper psoas major, and passes behind the kidney anterior to the quadratus lumborum. The nerve provides motor function to the anterolateral abdominal wall muscles. Its anterior branch emerges above the superficial inguinal ring to innervate the skin above the pubic region; the lateral branch descends over the iliac crest to innervate the gluteal region. Injury to the anterior branch during appendectomy causes decreased sensation at the suprapubic region. (Choice A) The femoral nerve arises from the L2-L4 nerve roots. It provides sensation to the upper thigh and inner leg and innervates muscles that extend the knee. (Choice B) The genitofemoral nerve arises from the L1-L2 nerve roots and provides sensation to the upper anterior thigh and motor function to parts of the genitalia (eg, cremasteric reflex in men, mons pubis in women). (Choice D) The ilioinguinal nerve originates from the L1 nerve root and accompanies the spermatic cord through the superficial inguinal ring. It provides sensation to the upper and medial thigh and parts of the external genitalia. (Choice E) The lateral femoral cutaneous nerve arises from the L2-L3 nerve roots and provides sensation to the skin on the lateral thigh. (Choice F) The obturator nerve arises from the L2-L4 nerve roots. It innervates the skin of the medial thigh and provides motor function for the adductor muscles of the lower extremity.

A 35-year-old woman comes to the office for evaluation of anxiety. The patient works as a mechanical engineer and recently declined a promotion to be a project manager. Although her salary would have increased significantly, she felt that overseeing other employees and leading team meetings would be too stressful. She says, "If something were to go wrong, everyone would blame me. I don't even know why they offered me this position." The patient enjoys her job but tends to eat lunch by herself because she feels that her coworkers do not like her appearance or sense of humor. She has never had a long-term romantic partner but fantasizes about getting married someday. The patient lives alone, rarely socializes with friends, and is close with her mother, whom she describes as "the person I can always rely on no matter what." Which of the following is the most likely diagnosis? A. Acute stress disorder (0%) B. Adjustment disorder with anxiety (%) C. Antisocial personality disorder (%) D. Avoidant personality disorder (%) E. Generalized anxiety disorder (%) F. Paranoid personality disorder (%) G. Schizoid personality disorder (%)

D. Avoidant personality disorder (%)

4-year-old boy is brought to the emergency department with dehydration. He has had several days of decreased oral intake, and today his parents could not get him to drink anything. The patient has received no vaccinations due to parental beliefs. Vital signs are normal except for mild tachycardia. Physical examination shows decreased skin turgor and sunken eyes. His jaw muscles are tight. Neurologic examination shows increased tone throughout and 3+ patellar reflexes. There is a small, healed puncture wound on his lower leg. The father says that the boy fell on a piece of chain-link fence in their backyard last week. Release of which of the following neurotransmitters is most likely to be directly impaired in this patient? A. Acetylcholine (%) B. Dopamine (%) C. Glutamate (%) D. Glycine (%) E. Serotonin (%)

D. Glycine (%) (or GABA!)

An 11-month-old boy is brought to the office due to irregular jerking movements. His mother states that for 2 weeks he has looked pale and tired, and he has been more fussy and less playful than usual. Temperature is 36.7 C (98 F), blood pressure is 100/60 mm Hg, pulse is 114/min, and respirations are 16/min. Physical examination reveals spontaneous bursts of nonrhythmic conjugate eye movements in various directions. The patient also has myoclonus involving the trunk and limbs as well as generalized hypotonia. A right-sided, nontender, immobile abdominal mass is palpated. There is no hepatosplenomegaly, and bowel sounds are normal. Complete blood count reveals anemia, and urine is positive for elevated levels of catecholamine breakdown products. Which of the following is the most likely diagnosis? A. Carcinoid tumor (%) B. Ewing sarcoma (%) C. Medulloblastoma (%) D. Neuroblastoma (%) E. Non-Hodgkin lymphoma (%) F. Pheochromocytoma (%) G. Wilms tumor (%)

D. Neuroblastoma (%) Nonrhythmic conjugate eye movements and involuntary jerking movements of the trunk and limbs (opsoclonus-myoclonus syndrome) in a young patient should prompt evaluation for neuroblastoma. This is the most common extracranial solid neoplasm of childhood and arises from neural crest cells of the adrenal medulla or sympathetic ganglia. Patients typically present at age <2 with a firm abdominal mass, most often involving the adrenal gland, and constitutional symptoms (eg, weight loss, fatigue). Bone marrow infiltration can cause anemia or pancytopenia, and orbital metastases may result in proptosis and/or periorbital ecchymoses. Although rare, opsoclonus-myoclonus is a paraneoplastic syndrome highly associated with neuroblastoma and is believed to be an autoantibody response to central nervous system antigens. The majority of patients with neuroblastoma have elevated catecholamine metabolites (eg, HVA, VMA) due to the neural crest origin. Biopsy of the mass is diagnostic and will reveal small round blue cells and Homer Wright rosettes. Tumor tissue is subsequently tested for N-myc amplification, which predicts a poor prognosis

A 3-week-old boy with discharge from the umbilicus is brought to the clinic by his parents. His postnatal course was uncomplicated, with shriveling of the cord around 14 days of life. Vital signs are normal. Examination of the area reveals a small reducible umbilical hernia, minimal clear to straw-colored discharge from the umbilicus, and erythema around the area. Laboratory results are as follows: Hemoglobin 12 g/dL Hematocrit 36% Leukocytes 11,000 cells/mm3 Neutrophils 50% Lymphocytes 45% Which of the following is the most likely cause of this child's condition? A. Absence of neutrophil migration (%) B. Duplication of the ureter (%) C. Incomplete closure of anterior abdominal wall (%) D. Persistence of allantois remnant (%) E. Persistence of omphalomesenteric duct (%)

D. Persistence of allantois remnant (%) Around 3 weeks gestation, the yolk sac forms a protrusion (allantois) that extends into the urogenital sinus. The upper part of the urogenital sinus gives rise to the bladder. The allantois, which originally connected the urogenital sinus with the yolk sac, becomes the urachus, a duct between the bladder and the yolk sac. Failure of the urachus to obliterate before birth leads to several abnormalities: Complete failure of obliteration of the urachus results in a patent urachus that connects the umbilicus and bladder. Patients present with straw-colored urine discharge from the umbilicus, which is exacerbated by crying, straining, or prone position. Local skin irritation can cause erythema. Failure to close the distal part of the urachus (adjacent to the umbilicus) results in a urachal sinus. This presents with periumbilical tenderness and purulent umbilical discharge due to persistent and recurrent infection. Failure of the central portion of the urachus to obliterate leads to a urachal cyst.

A 29-year-old woman comes to the office due to persistent fatigue over the last 4 years. She has also felt unhappy during this period, ever since being let go from her previous job. The patient describes her fatigue as "having little energy to do things." When asked what she enjoys, she replies that "everything in life is a chore" and that she feels hopeless that her life will improve. The patient has no suicidal thoughts, problems with concentration, or changes in appetite or sleeping patterns. She used marijuana as a teenager and drinks 1 or 2 glasses of wine on weekends. Detailed workup, including urine toxicology screen, is negative. Which of the following is the most likely diagnosis? A. Adjustment disorder (%) B. Borderline personality disorder (%) C. Major depressive disorder (%) D. Persistent depressive disorder (dysthymia) (%) E. Substance-induced mood disorder (%)

D. Persistent depressive disorder (dysthymia) (%) This patient's chronic depression, fatigue, and hopelessness are consistent with a diagnosis of persistent depressive disorder. Diagnosis requires depressed mood more days than not for at least 2 years (1 year in children) and at least 2 other depressive symptoms (Table). In DSM-5, persistent depressive disorder includes both "pure dysthymic syndrome" and chronic major depression or dysthymia with concurrent or intermittent major depressive episodes. This patient would be diagnosed with "pure dysthymic syndrome" as she has never met the criteria for a major depressive episode. Diagnosis of persistent depressive disorder requires ruling out medical and substance-induced etiologies and differentiation from other psychiatric disorders. Persistent depressive disorder is treated with antidepressants, psychotherapy, or a combination of these

A 25-year-old man comes to the hospital due to acute-onset shortness of breath. The patient has a history of cystic fibrosis and multiple hospitalizations for recurrent pneumonia. He has a frequent productive cough at baseline. He does not use tobacco. Blood pressure is 80/50 mm Hg, pulse is 110/min, and respirations are 24/min. Examination shows mild cyanosis and subcutaneous crepitus. Breath sounds are decreased on the left. Which of the following is most likely responsible for this patient's acute symptoms? A. Alveolar consolidation due to inflammatory exudate (%) B. Bronchial obstruction with alveolar air resorption (%) C. Diffuse constriction of bronchioles (%) D. Increased dead-space ventilation (%) E. Loss of intrapleural negative pressure (%)

E. Loss of intrapleural negative pressure (%) This patient with sudden-onset shortness of breath and a physical examination showing subcutaneous crepitus and unilaterally decreased breath sounds most likely has a pneumothorax. In cystic fibrosis, chronic lung damage, combined with mucus plugging and large alveolar pressure surges (eg, coughing), predisposes to spontaneous alveolar rupture. Pressure in the lungs is normally equivalent to atmospheric pressure (ie, 0 cm H2O) at end expiration, and the pressure in the intrapleural space is negative (eg, −5 cm H2O) due to the expanding tendency of the chest wall and collapsing tendency of the lungs. Alveolar rupture creates continuity between the lungs and the pleural space, with pressure equalization and loss of intrapleural negative pressure. Shortness of breath results from inability to expand the ruptured lung, and during rupture, air may be forced into the subcutaneous tissues of the chest wall to cause crepitus.

A 67-year-old man comes to the office due to severe fatigue for the past several months. The patient cannot eat as much as he used to and has lost nearly 10 kg (22 lb) in the past 6 months. Physical examination shows mucosal pallor, hepatomegaly, and massive splenomegaly. Further evaluation reveals a gain-of-function mutation of a non-receptor tyrosine kinase protein in hematopoietic cells, leading to persistent activation of signal transducers and activators of transcription (STAT) proteins. This patient is most likely suffering from which of the following disorders? A. Acute promyelocytic leukemia (%) B. Chronic lymphocytic leukemia (%) C. High-grade non-Hodgkin lymphoma (%) D. Mantle cell lymphoma (%) E. Primary myelofibrosis (%)

E. Primary myelofibrosis (%) The chronic myeloproliferative disorders are bone marrow diseases characterized by overproduction of myeloid cells. Primary myelofibrosis is caused by atypical megakaryocytic hyperplasia, which stimulates fibroblast proliferation, resulting in progressive replacement of the marrow space by extensive collagen deposition. In the early stages, there is marrow hypercellularity with minimal fibrosis, but as the disease progresses, pancytopenia can result. Hepatomegaly and massive splenomegaly develop because the loss of bone marrow hematopoiesis is compensated for by extramedullary hematopoiesis. The peripheral smear characteristically shows teardrop-shaped red blood cells (dacrocytes) and nucleated red blood cells. With the exception of chronic myelogenous leukemia, the chronic myeloproliferative disorders (especially polycythemia vera) frequently harbor a mutation in the nonreceptor cytoplasmic tyrosine kinase, Janus kinase 2 (JAK2). This mutation results in constitutive tyrosine phosphorylation activity, and consequently, in the cytokine-independent activation of the signal transducers and activators of transcription (STAT) pathway. Once they are activated, STAT proteins translocate to the nucleus and promote transcription. A JAK2 inhibitor (ruxolitinib) has been approved for treatment of primary myelofibrosis In acute promyelocytic leukemia, t(15;17) leads to the formation of a fusion gene between the promyelocytic leukemia (PML) and the retinoic acid receptor alpha (RARA) genes. The abnormal PML/RARα fusion protein blocks differentiation of myeloid precursors

A 43-year-old man comes to the office due to difficulty walking. The patient was seen at an outpatient clinic 2 days ago and received a right-sided deep intramuscular injection. He had no trouble walking at the time of the appointment but started having problems later that day. The patient has no history of trauma or pain at the injection site. Physical examination is negative for local erythema and swelling, and the patient has full strength against resistance on knee flexion and ankle plantar flexion bilaterally. When the patient is asked to walk across the room, his left hip drops every time he raises his left foot. Which of the following locations is the most likely site of this patient's intramuscular injection? A. Inferolateral quadrant of the buttock (%) B. Inferomedial quadrant of the buttock (%) C. Superior portion of the posterior thigh (%) D. Superolateral quadrant of the buttock (%) E. Superomedial quadrant of the buttock (%)

E. Superomedial quadrant of the buttock (%)

A 78-year-old man is brought to the emergency department due to fever, cough, and shortness of breath. The patient recently moved into an assisted living facility after living with his family that owned several pets. He has a 40-pack-year smoking history. Temperature is 39.4 C (103 F), blood pressure is 106/62 mm Hg, pulse is 112/min, and respirations are 28/min. There is dullness to percussion and bronchial breath sounds over the left lung. Chest x-ray reveals a left lower lobe consolidation. Sputum microscopy shows gram-positive diplococci. Which of the following would have been most helpful in preventing this patient's lung infection? A. Avoidance of exposure to bird droppings (%) B. Immediate chemoprophylaxis after exposure (%) C. Immunization with inactivated microbial agent (%) D. Periodic culture and disinfection of water supply (%) E. Vaccination with bacterial polysaccharide (%)

E. Vaccination with bacterial polysaccharide (%) This patient with fever, pulmonary symptoms, and a lobar consolidation on chest x-ray has pneumonia. The presence of gram-positive diplococci in the sputum indicates the underlying pathogen is Streptococcus pneumoniae, the leading cause of community-acquired pneumonia. Over 90 strains of S pneumoniae have been identified; they are distinguished based on antigenic variations in the capsular polysaccharide, the major virulence factor of the bacteria. Antibodies against the polysaccharide capsule are generated during infection and provide long-lasting immunity against that strain. The pneumococcal vaccine contains polysaccharide antigens from the most common disease-causing serotypes leading to the generation of protective antibodies against these strains. In the United States, 2 types of pneumococcal vaccinations are available: Pneumococcal polysaccharide vaccine contains capsular material from 23 serotypes. Because polysaccharides cannot be displayed by the major histocompatibility complex of antigen-presenting cells (only peptides can), immunogenicity to this vaccine is T-cell independent and driven largely by B-cell activation. This leads to a moderate antibody response that is effective for most patients but not infants (age <2). Pneumococcal conjugate vaccine consists of capsular polysaccharides from 13 serotypes that have been covalently attached to recombinant, inactivated diphtheria toxin. Protein conjugation allows the polysaccharide to be displayed by the major histocompatibility complex and induces a stronger immunogenic response that involves T-cell-mediated B-lymphocyte activation. This generates higher- affinity antibodies and memory cells and also creates mucosal antibodies, which reduce colonization rates. Pneumococcal vaccination significantly reduces the risk of invasive pneumococcal disease. Routine vaccination is recommended for all children as part of their childhood immunization series. Adults age >65 and those at high risk for invasive disease (eg, HIV, asplenia, other immunosuppressed states) should also be vaccinated. Choice C) The influenza vaccine contains 3 or 4 strains of inactivated influenza virus. Influenza usually causes abrupt-onset fever, headache, myalgia, and malaise and would not appear on Gram stain

60-year-old man who was recently diagnosed with hypertension comes to the office for follow-up. He was treated with lisinopril but stopped a week ago due to a dry, nagging cough. Past medical history is notable for type 2 diabetes mellitus with moderately increased albuminuria but normal creatinine clearance. His other medications include metformin and rosuvastatin. The patient does not smoke or drink alcohol. His blood pressure is 150/92 mm Hg. BMI is 31 kg/m2. Physical examination, including the heart and lungs, is unremarkable. Which of the following is the best treatment for this patient's hypertension? A. Diltiazem (%) B. Hydralazine (%) C. Metoprolol (%) D. Ramipril (%) E. Valsartan (%)

E. Valsartan (%) Diabetes causes impaired autoregulation of glomerular blood flow, leading to significant elevations of intraglomerular pressures and chronic glomerular injury. Patients with diabetes and hypertension are at especially high long-term risk for chronic kidney disease. Angiotensin-converting enzyme (ACE) inhibitors (eg, lisinopril) cause preferential dilation of the glomerular efferent arteriole, lowering intraglomerular pressures and reducing the risk of chronic glomerular injury. In addition to converting angiotensin I to angiotensin II, ACE normally degrades bradykinin and substance P. Inhibition of ACE leads to elevated bradykinin and substance P levels and a nonproductive cough. Angiotensin receptor blockers (ARBs) have hemodynamic effects similar to those of ACE inhibitors but do not affect bradykinin levels and do not cause a cough. Replacing this patient's ACE inhibitor with an ARB (eg, losartan, valsartan) will eliminate the cough while still providing the same long-term renovascular benefits

A 23-year-old woman is being evaluated for recurrent episodes of urinary tract infection. She has had 5 episodes of cystitis and an episode of pyelonephritis over the past year. The symptoms tend to occur a few days following sexual intercourse. The patient has no other medical problems and takes no medications. Her temperature is 36.7 C (98 F), blood pressure is 110/70 mm Hg, respirations are 16/min, and pulse is 65/min. Abdominal and genitourinary examinations are normal. Which of the following is the most likely predisposing factor for pyelonephritis in this patient? A. Frequent voiding (%) B. Hematogenous bacterial spread (%) C. Suppression of endogenous flora (%) D. Urethral colonization (%) E. Vesicoureteral urine reflux (%)

E. Vesicoureteral urine reflux (%) Suppression of endogenous flora, colonization of the distal urethra by pathogenic gram-negative rods, and attachment of these pathogens to the bladder mucosa are the stages of pathogenesis in lower urinary tract infections. Anatomic or functional vesicoureteral reflux is almost always necessary for the development of acute pyelonephritis.

A 42-year-old man comes to the office seeking advice on male contraception. He and his wife have 6 children and do not want any more, and his wife wants to stop taking oral contraceptive pills. The patient's medical history is notable for an appendectomy, during which he had no complications from the procedure or the associated anesthesia. He does not smoke. On examination, the patient has a normal circumcised penis with no visible genital lesions and no palpable abnormalities in the scrotum. After appropriate discussion regarding contraceptive options, the patient elects to undergo a vasectomy. The patient should be advised to expect which of the following side effects during the first few months following the procedure? A. Decreased interest in sexual activity (%) B. Difficulty in maintaining an erection (%) C. Large reduction in the volume of ejaculate (%) D. Reduced testosterone production (%) E. Viable sperm in the ejaculate (%)

E. Viable sperm in the ejaculate (%) The vas deferens (ductus deferens) is a long muscular duct that runs from the epididymis, via the spermatic cord, to the ejaculatory duct. In addition to transporting sperm, it functions as a reservoir to store and protect sperm following spermatogenesis. Vasectomy is a male sterilization procedure that involves transection of the vas deferens bilaterally to block the transport of new sperm. However, vasectomy has no effect on existing sperm distal to the transection; a patient can still have viable sperm in the distal vas for up to 3 months and at least 20 ejaculations following vasectomy. Sexual intercourse can typically be resumed within a week following the procedure, but pregnancy is still possible due to residual sperm in the ejaculate. Therefore, another method of birth control must be used after vasectomy until semen analysis confirms azoospermia.

Much of the deleterious remodeling that occurs following myocardial infarction is likely driven by neurohormonal signaling via _____. Accordingly, ACE inhibitors (eg, lisinopril) reduce the deleterious remodeling that takes place following myocardial infarction, minimizing LV dilation and helping preserve LV function

angiotensin II

Systemic corticosteroids (eg, oral prednisone) are used in short courses to treat acute asthma exacerbations, whereas inhaled corticosteroids (eg, ____) reduce the frequency and severity of exacerbations and are used for long-term asthma control in patients with persistent symptoms. Suppression of airway inflammation is evident within hours of administration but reaches maximal effect after several months of inhaled therapy. Nonadherence to long-term therapy can increase the risk of life-threatening asthma exacerbation

fluticasone

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by low plasma sodium and osmolality, inappropriately concentrated urine, and clinically____ volume status. An important cause of SIADH is a paraneoplastic effect secondary to small cell carcinoma of the lung.

normal (euvolemic hyponatremia)

Meckel diverticulum results from failure of obliteration of the vitelline (or _____ duct). Toddlers may have painless gastrointestinal bleeding due to ectopic gastric mucosa

omphalomesenteric

Primary (idiopathic) membranous nephropathy is associated with IgG4 antibodies to the______, which might play a role in development of the disease. Antibody titers are useful for diagnosis and correlate with disease activity

phospholipase A2 receptor