Infectious Disease Q bank

confirmation (required) with serum testing via HIV-1/HIV-2 differentiation immunoassay or western blot.

A 24-year-old man who is sexually active and has intercourse with men and does not always use condoms presents with reports of the "flu" for the past 3 weeks. You suspect acute HIV syndrome and obtain a rapid antigen/antibody combination assay. If positive what should is next step with discharge?

Dengue fever

A 26-year-old man presents with a severe retro-orbital headache, a sudden-onset fever of 103.3°F (39.6°C), nausea, and severe myalgias 6 days after returning from a trip. On exam, he has a morbilliform rash on his abdomen and back. Which of the following is most likely responsible for his symptoms?

Chagas disease

A 27-year-old previously healthy man visiting the United States from Guatemala presents to the ED with acute dyspnea and a fever. On exam, you note facial and lower extremity edema, hepatosplenomegaly, and lymphadenopathy. What is the most likely diagnosis?

five days of azithromycin. classic presentation of Cat Scratch disease caused by Bartonella henselae.

A 4-year-old girl presents to the office with lymphadenitis of several left axillary and cervical lymph nodes. An erythematous papule is noted on the left hand. What is the treatment of choice?

Enterobiasis, or pinworms

A 5-year-old boy presents with perianal itching that is worse at night. His mother looked in the area and thought she saw worms. What is the most likely diagnosis?

No. Antibiotics do not prevent poststreptococcal glomerulonephritis.

Does treatment of a group A strep infection with antibiotics prevent poststreptococcal glomerulonephritis?

11-12 years old (although it can be given as early as 9 years of age). up to 45 years old.

The 9-valent human papillomavirus vaccination is available in the United States for both men and women what age? Recent guideline changes now allow the vaccination to be given to individuals up to what age?

the gastrointestinal tract an intravascular catheter and from a localized focus of infection

The three most common ways that Candida gains access to the bloodstream are through what?

autoimmune disease As a result of the low specificity, a positive RPR should always be followed up by a more specific treponemal test

Apart from malaria what else can cause a false positive rapid plasma reagin (RPR) (the diagnostic test that looks for non-specific antibodies to Treponema pallidum)

is supportive care plus vitamin A if signs of vitamin A deficiency, severe symptoms, or child < 2

Treatment of rubeola

Influenza

a Patient presenting with sudden onset of fever, headache, cough, myalgia, sore throat, fatigue during the winter most likely has what?

Ehrlichiosis and Anaplasmosis, also RMSF can be found in south central

a pt presenting w/ a fever, headache, and myalgias ten days after hiking in the woods in the South Central and South Atlantic United States (ie North Carolina). Apart from lyme what other tick born illnesses should be on your radar given this geographic location?

Pregnancy, women intending to become pregnant within one month, immunocompromised patients, patients on high dose steroids and patients with severe allergies to previous MMR vaccination or neomycin.

absolute contraindications for the mumps, measles, rubella (MMR) vaccine include what?

Receptive anal intercourse with an individual who is positive for HIV followed by receptive vaginal intercourse.

activity that carries the highest risk for transmission of the HIV

tissue PCR or viral culture

diagnosis of genital herpes

B. pertussis PCR (obtained nasopharyngeal specimen)

diagnostic method of choice for a pt you suspect has whooping cough?

a blanching erythematous rash with macules that become petechial over time.

hallmark of RMSF is what?

Measles aka the rubeola virus.

maculopapular, erythematous, blanching rash that begins on the head and face and spreads downward, occurring two to four days after onset of a high fever makes you think of what??

respiratory airway protection (Patients typically die from respiratory failure.), supportive care, and administration of the botulism antitoxin. Patients typically die from respiratory failure.

management of botulism

thick and thin peripheral smear under light microscopy (gold standard dx of malaria)

otherwise healthy 27-year-old man presents with several days of fever, drenching sweats, and shaking chills one week after returning from India. Which of the following is most likely to reveal the diagnosis?

Consumption of undercooked pork produces an intestinal infection that is caused by the adult worm. Individuals infected with an adult worm can infect themselves or others with the eggs via fecal-oral route.

pathophysiology of Neurocysticercosis

A normal white blood count and thrombocytopenia and sometimes hyponatremia are common laboratory findings commonly found in RMSF.

sxs of a fever, arthralgias, headache, rash, and a history of a tick bite. What laboratory finding would you expect to see in your most likely diagnosis?

dengue fever

the second most important tropical, febrile illness after malaria caused by a bite from the Aedes aegypti mosquito

Catarrhal maybe 1 week prodrome of feeling "flu like" Paroxysmal on 2nd week whooping cough phase begins Convalescent a gradual reduction in sx over 1-2 months

the stages of pertussis include?

classic dengue - the type seen in travelers returning from Africa, the Americas, and Indian subcontinent and hemorrhagic dengue

there are 2 types of dengue fever what are they? what is the type seen in travelers returning from Africa, the Americas, and the Indian subcontinent?

Pregnancy: acyclovir or valacyclovir for 7-10 days after primary infection and from 36 weeks to delivery

treatment of genital herpes infection in pregnant female

tender inguinal/femoral lymphadenopathy

what should you look for in a pt who has painless penile ulcer or vesicle you think may be assoc'd w/ lymphogranuloma venereum

due to the severe myalgias or dramatic bone pain

why is classic dengue fever aka "breakbone fever"

acute rheumatic fever

what disease diagnosis is based on the Jones criteria?

The female Anopheles mosquito.

What is the vector that spreads malaria?

Most likely cerebral toxoplasmosis, the most common cause of focal encephalitis in patients with AIDS A contrast CT scan of the brain reveals multiple ring-enhancing lesions without evidence of midline shift. Treatment should be initiated with pyrimethamine and sulfadiazine

26-year-old woman with a known history of AIDS presents to the ED for strange behavior according to her boyfriend. Reportedly, she complained of a headache for a few days prior. What would you expect to see on a contrast CT scan of the brain for your suspected diagnosis, and how would you treat?

about ingestion of certain foods, such as home-canned goods or raw honey.

A 23-year-old woman presents with a complaint of nausea, vomiting, abdominal pain, and diarrhea followed by weakness that started in her bilateral arms and moved down to her bilateral legs. What questions should you ask her?

Clinically, RMSF is characterized by high fevers, arthralgias, myalgias, and a petechial rash, which begins on the ankles and wrists and spreads centrally. Early in the disease, there is often no rash, and some patients with confirmed RMSF never go on to develop a rash.

A 12-year-old boy presents with high fever, muscle and joint aches, and headache for two days. He states he just got back from a camping trip in North Carolina. His exam is unremarkable. Labs are normal except for platelets of 95,000/µL and a serum sodium of 128 mEq/L. What is the most likely diagnosis?

Echo bc the most severe subsequent complication is rheumatic heart disease

A 12-year-old girl complaining of two weeks of joint pain. Initially, the pain started at the same time as a fever, first in her knees, then her ankles, and now she feels like her elbows are bothering her. Her only recent illness was strep throat which was treated with amoxicillin. Which of the following is the most appropriate diagnostic test?

Neurocysticercosis Neurocysticercosis should be suspected in any child with new onset seizures and a history of living in an endemic area or exposed to someone from an endemic area.

A 16-year-old girl is seen in the emergency room after a new, generalized tonic-clonic seizure. She has no history of seizures and recently moved from the Caribbean with her family. What etiology is suspected?

The patient has signs and symptoms of chancroid, tx w/ azithromycin 1 g po a sexually transmitted infection caused by Haemophilus ducreyi. The infection is most common in developing and third world countries.

A 17-year-old boy had unprotected sex during a trip to South Africa. Symptoms began with a very painful papule on his penis. The papule gradually ulcerated, and its edges became irregular. One week later, he developed painful right-sided inguinal adenopathy. Which empirical antibiotic is most likely to treat his infection?

itraconazole. This patient has sporotrichosis, a fungal infection - It is most commonly seen in gardeners, farmers, landscapers, and other agricultural workers. classically associated with a seemingly innocuous puncture wound from a rose bush thorn and then spreads proximally along lymphatic channels with skip lesions

A 22-year-old landscaper presents to the ED with a rash that began approximately three weeks ago. He reports it started with a single bump on his right forearm that has been oozing fluid. He subsequently developed lesions tracking up his arm. what is the most appropriate treatment for this condition?

involuntary muscle movements known as chorea. The pt has acute rheumatic fever, which is most commonly caused by Streptococcus pyogenes. The major criteria are polyarthritis, active carditis, subcutaneous nodules, erythema marginatum, and involuntary muscle movements known as chorea. minor criteria are fever, joint pains, elevated erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP), and prolonged PR interval on ECG.

A 6-year-old boy presents to the emergency department with his parents with concerns of intermittent fidgety movements. The parents report that the movements are involuntary and occur at random. The patient has no significant medical history. However, the parents also report that he had a sore throat and fever about 3-4 weeks ago that resolved on its own. what is this called and what is the cause of this symptom in this patient?

Tetanus - Muscle rigidity starting in the jaw and facial muscles and descending to the limbs is the major clinical manifestation. Admission to the intensive care unit.

A 60-year-old man with a history IVDU presents to the ED with complaints of inability to open his mouth (lockjaw) and difficulty swallowing. He is not up-to-date on his immunizations. On PE stimulation of his posterior pharynx causes him to bite down instead of gag. You also note areas of erythema and purulent discharge in the antecubital fossae. What is diagnosis and what is the most appropriate management?

Remove the central line and start Caspofungin. The decision to remove an existing central venous catheter is somewhat dependent on whether the patient is neutropenic. Catheter removal is recommended as soon as possible for all non-neutropenic patients with candidemia. The decision is more nuanced in patients who are neutropenic because they are more likely to have candidemia from a source besides the indwelling catheter. .

A 75-year-old woman with a history of type 2 diabetes is intubated for hypoxemia 2ndary to CAP and has a central venous catheter in place. She develops a new fever on day 5 of admission and blood cultures return Candida. What is the recommended management of the patient's most recent blood culture results?

every three days with P. vivax and P. ovale (vivax is most common) every four days for P. falciparum and P. malariae. (falciparum is most deadly)

Classically, malaria begins with a flu-like prodrome that progresses to cyclical episodes of chills followed by fever, each lasting about two hours. These episodes recur how often?

6 & 11

HPV 16 and 18, are known to cause cervical and anogenital cancers but what strains cause condyloma acuminata?

Generally, no, because antibodies are fairly prevalent in the general population.

In the pt in previous question, should you order serologic testing to diagnose toxoplasmosis?

History of eating honey or residing near construction site (exposure to soil) sx = constipation, floppy baby, feeble cry Tx = IV botulism IG

Infant Botulism history, symptoms, and tx

Combination of two HIV medicines: tenofovir (NRTI) and emtricitabine (NRTI) Taken daily for high risk for HIV

Oral Preexposure Prophylaxis (PrEP) medications for HIV ppx

For 7 days after completion of single dose antibiotic treatment.

Patients diagnosed with chlamydia or gonorrhea should be counseled to avoid sexual contact for how long?

cough, coryza and conjunctivitis,

Prior to the rash, measles is associated w/ a prodrome of high fever and "the 3 C's" which are what?

those who are from or traveled to tropical or resource limited countries

RF's for Neurocysticercosis

True, but this is a less common mode of transmission

T or F HIV may be transmitted by oral intercourse

True

T or F Treatment of RMSF is always doxycycline, even in children

Serum rubeola virus IgM antibody But patients being evaluated for testing should be isolated and additional testing including throat or nasopharyngeal swab for viral culture and a urine sample for viral culture should be ordered.

The most common laboratory test used in the diagnosis of measles is what?

False

True or false: In high-risk patients presenting for suspected influenza, antiviral treatment should be delayed until the results of diagnostic testing confirm the illness?

True

True or false: the majority of herpes simplex infections are asymptomatic?

calcified cysts ring enhancing lesions

What finding would you expect on MRI? or CT?

5-7 days. Although staph and strep are the causative organisms in most cases of skin structure and soft tissue infections, many patients receive broad-spectrum gram-negative and anaerobic therapy and are treated longer than recommended.

What is the appropriate treatment duration for cellulitis?

P. falciparum

What is the is the most virulent form of malaria that is able to cause severe organ dysfunction and death?

human papillomavirus More than 50% of sexually active individuals will contract (HPV) at some point in their lives

What is the most common sexually transmitted infection in the United States?

Spatula test.

What is the name of the test used to diagnosis tetanus in which stimulation of the posterior pharynx causes the patient to bite down instead of gag?

VDRL (Venereal Disease Research Laboratory test) -- the test for syphilis

What test may be falsely positive in malaria patients?

American dog tick.

What type of tick is the most common vector of Rocky Mountain spotted fever in the eastern and south central United States?

Chagas disease.

Which disease is transmitted by the reduviid bug?

Treponema pallidum Disorders characterized by genital ulcers (syphilis, herpes, chancroid, lymphogranuloma venereum, granuloma inguinale) have high rates of HIV cotransmission

Which of the following sexually transmitted infections has a high rate of cotransmission with HIV infection? Gardnerella vaginalis Neisseria gonorrhoeae Treponema pallidum Trichomonas vaginalis

the face

Which part of the body is spared by the erythema marginatum associated with acute rheumatic fever?

Non-albicans Candida species often have resistance to azoles.

Why are azoles not used as the initial treatment of candidemia?

Administer oseltamivir - Since the girl is younger than two years of age and is therefore at high risk for complications to influenza, post-exposure chemoprophylaxis is warranted.

You see a 15-month-old girl in the clinic for a well child visit. The mother is concerned because yesterday she was exposed to her four-year-old cousin who was febrile and later confirmed to have influenza B. Which of the following is the next best step?

dogs

bats are the the most frequently reported wildlife species associated with rabies in the United States but what animal most commonly transmits rabies worldwide?

4-10 wks after primary lesion -fever, malaise, , non-specific lymphadenopathy, rash over entire body, may include palms, soles, and oral mucosa and may resemble pityriasis rosea. (These are macular, discrete, sort of reddish-brown). Condylomata lata are painless, highly infectious gray white lesions that develop in warm moist sites. Self innocuable.

primary syphilis is characterized by a painless ulcer on his penis that will resolve spontaneously w/ or w/o tx. What characterizes secondary syphilis?

This patient is suffering from a retropharyngeal abscess and will need CT scan of the neck with IV contrast with emergent ENT consultation for possible operative intervention.

pt w/ fever, difficulty swallowing her saliva, trismus, and pain with neck extension -- but her oropharyngeal examination is unremarkable. Which of the following is the most appropriate next step in management?

chancroid and genital herpes

what 2 diseases should be on your ddx for painful penile lesion?

lymphogranuloma venereum, primary syphillis, granuloma inguinale

what 3 diseases should come be on your ddx if a pt has a painless penile lesion?