PANRE PANRE Infectious Disease 1 — Questions and Answers
Question 1: A 25-year-old presents with fever, headache, and a rash that began on the wrists and ankles and spread centrally after a tick exposure. What is the most likely diagnosis?
- Rocky Mountain Spotted Fever (Correct answer)
- Lyme Disease
- Ehrlichiosis
- Tularemia
Correct answer: Rocky Mountain Spotted Fever
Rocky Mountain Spotted Fever (RMSF) classically presents with fever, headache, and a centripetal rash beginning on the wrists and ankles caused by Rickettsia rickettsii.
Question 2: Which antibiotic is the drug of choice for Rocky Mountain Spotted Fever in all age groups, including children?
- Amoxicillin
- Doxycycline (Correct answer)
- Azithromycin
- Ciprofloxacin
Correct answer: Doxycycline
Doxycycline is the first-line treatment for RMSF in all patients, including children, due to its superior efficacy against Rickettsia species.
Question 3: A patient presents with a painless genital ulcer with indurated edges. Which organism is responsible?
- Neisseria gonorrhoeae
- Haemophilus ducreyi
- Treponema pallidum (Correct answer)
- Chlamydia trachomatis
Correct answer: Treponema pallidum
Primary syphilis is characterized by a painless, indurated genital chancre caused by Treponema pallidum.
Question 4: What is the preferred first-line agent for uncomplicated urinary tract infections in otherwise healthy adult women in the United States?
- Amoxicillin
- Ciprofloxacin
- Nitrofurantoin (Correct answer)
- Trimethoprim-sulfamethoxazole
Correct answer: Nitrofurantoin
Nitrofurantoin is a preferred first-line agent for uncomplicated UTIs due to low resistance rates and minimal impact on systemic flora.
Question 5: A patient with HIV has a CD4 count of 175 cells/µL. Which opportunistic infection prophylaxis must be initiated?
- Fluconazole for Cryptococcus
- TMP-SMX for Pneumocystis jirovecii pneumonia (Correct answer)
- Azithromycin for MAC
- Acyclovir for HSV
Correct answer: TMP-SMX for Pneumocystis jirovecii pneumonia
PCP prophylaxis with TMP-SMX is indicated when CD4 count falls below 200 cells/µL to prevent Pneumocystis jirovecii pneumonia.
Question 6: Which test is the gold standard for confirming active pulmonary tuberculosis in a patient with a positive PPD and suspicious chest X-ray?
- Chest X-ray alone
- Sputum AFB smear and culture (Correct answer)
- QuantiFERON-TB Gold blood test
- CT scan of the chest
Correct answer: Sputum AFB smear and culture
Sputum acid-fast bacilli smear and culture remain the gold standard for confirming active pulmonary TB infection.
PANRE PANRE Infectious Disease 1
A 25-year-old presents with fever, headache, and a rash that began on the wrists and ankles and spread centrally after a tick exposure.
What is the most likely diagnosis?