Infectious Disease

1

100

A college freshman presents with: low-grade fever, post-auricular lymphadenopathy, headache, sore throat, and a macular rash on the face that spread caudally to the neck and trunk. What is the most likely diagnosis?

Rubella presents with this.

200

A 3 year old child present with malaise, fever, vomiting. He develops myocarditis. What virus is known for causing myocarditis? What CATEGORY of virus is this?

Coxsackie B is an type of enterovirus! Coxsackie can also cause hand food mouth disease, and also herpangina.

300

A 5 year old is diagnosed with measles. The parents are worried about the 7 month old sister. What would you recommend?

Give the Measles Vaccine for 6-11 months of age. This does NOT count as their 12 month vaccination, you still need to give them 2 additional doses. Give IVIG for < 6 months of age.

400

A 9-month-old infant who attends childcare presents with a 2-day history of vomiting and copious, nonbloody, watery diarrhea. Several other children in his childcare have similar symptoms. You are concerned he has Rotavirus. What is the MOST sensitive test for rotavirus? What will you actually order to diagnose it in the clinical setting?

Enzyme-linked immunosorbent assay testing is available clinically, is affordable, and has high sensitivity and specificity, although polymerase chain reaction is the most sensitive method to detect rotavirus, it is primarily a research tool.

500

A year old child presents with a four day history of irritability and recurrent fevers. Today he is afebrile and had a diffuse erythematous rash on his trunk. You diagnosis the child with roseola. Which of the following is a common complication of this disease?

Roseola is caused by HHV-6 virus and is classically associated with the onset of rash after fevers. A known complication of Roseola is Febrile seizures.

2

100

A 9 year old comes back from the Rocky Mountains with watery, smelly diarrhea. He has had multiple episodes of flatulence. He has also been burping a lot. What is the diagnosis? What is the treatment, if any?

Giardiasis. Giardiasis if severe, can be treated with nitroimidazoles (Metronidazole)

200

Which is the preferred diagnostic test to confirm an HIV infection in one month old infant born to an HIV positive mother?

HIV DNA PC! HIV serology can be falsely positive for up to 18 months after birth HIV p24 antigen test – false positives and negatives Not recommended HIV culture – requires 4 weeks, not readily available Not recommended HIV DNA PCR Highly sensitive and specific Considered infected if two separate positive tests CD4/CD8 ratio Not useful in the neonatal period

300

A child presents with signs of acute abdominal obstruction. The patient is from a tropical region. You suspect a parasite. This parasite ALSO causes Loffler syndrome. Name the parasite, and what is Lofflier syndrome?

Ascaris Lumbricoides. Causes pulmonary infiltrates with increased eosinophils

400

A child presents to the ED with several days of severe, watery, diarrhea. She had been swimming at a friend's house earlier this week. A culture grows an acid-fast organism. What is the cause of the child's diarrhea?

Cryptosporidium

500

Match the following encephalitis with the appropriate clinical characteristic: Japanese encephalitis Eastern equine encephalitis Post-infectious encephalitis St. Louis encephalitis La Cross encephalitis SIADH Decorticate or decerebrate posturing Aedes triseriatus Multiple levels of CNS involved Highest mortality

Japanese encephalitis-decorticate or decerebrate posturing Eastern equine encephalitis-highest mortality Post-infectious encephalitis- involvement of multiple CNS levels St. Louis encephalitis-SIADH La Cross encephalitis-Aedes triseriatus

3

100

Which is more likely to have a positive blood culture, TSS from staph or strep?

Strep!

200

A 16 month old presents with thick, nasal, purulent discharge, mild fever, and abdominal pain. What is the most likely diagnosis?

Group A Strep. Toddlers with strep do not typically present with pharyngitis.

300

What is the most common organism that causes Otitis externa? What medication be put in the ear to PREVENT otitis external?

Pseudomonas. 2% acetic acid or dilute alcohol

400

A healthy 3 year old presents with a fever to 39.8 and stridor. The child reportedly has had a 3 -day history of a “bark-like” cough, low grade fever and URI symptoms. She became acutely worse today and appears “toxic” The most likely diagnosis is and what is the organism?

Bacterial Tracheitis - typically by Staph

500

Which clinical factor best distinguishes the life threatening form of leptospirosis from the more common self-limited form of leptospirosis? a. azotemia b. pneumonia c. meningitis d. dehydration e. jaundice

Jaundice indicates icteric leptospirosis, which is a more serious condition with a higher mortality.

4

100

What vaccines are contraindicated with a history of anaphylaxis allergic reaction to eggs?

Influenza, Yellow Fever. NOT MMR.

200

What electrolyte abnormality is associated with Rocky Mountain Spotted Fever?

HYPONATREMIA - sometimes RMSF looks like meningococcemia, but hyponatremia is more classically associated with RMSF

300

A 13 year old from Missouri presents with interstitial pneumonia, palate ulcers, and splenomegaly. What is the most likely diagnosis?

Histoplasmosis

400

Match the side effect with the appropriate antibiotic: Isoniazid Rifampin Streptomycin Ethambutol Hepatitis Inhibition of the metabolism of oral contraceptives Optic neuritis

Ethambutol - optic neuritis Isoniazid - Hepatitis Rifampin - inhibition of the metabolism of OCP

500

Name 4 disease conditions that result largely from toxin production

Tetanus, botulism, diptheria, toxic shock, staph scalded skin syndrome, scarlet fever

5

100

A 15 year old presents with hyperpigmented circular macules on his back and chest that seem to darken in sun. What is the diagnosis, organism, and treatment?

Tinea versicolor, malassia furfur, selenium sulfide

200

Draw out the geographical distribution of histoplasmosis, coccidiomycosis, and blastomycosis.

Histoplasmosis: OHio, Missippi, Missouri River Valley Coccidiomycosis: California, Arizona, Texas, Utah,Central and south america Blastomycosis: Southeastern and central states and those bordering great lakes

300

Name two types of hookworms.

Ancylostoma duodenale, Necator americanus

400

Dexamethasone is used in the treatment of what type of meningitis, and why?

Specifically H. Influenzae to decrease the risk of hearing loss

500

What type of malaria is predominant in which areas, and how does treatment differ?

I'll let Dr. Jacobs answer