Bacteriology USMLE Step 1 Practice Question
A 3-year-old male presents with a 1-day history of loose stools, fever, abdominal cramping, headache, and myalgia. Vital signs show temperature 38.9°C, heart rate 112/min, blood pressure 95/60 mmHg, and respiratory rate 24/min. Stool examination reveals no blood or leukocytes. Serum sodium is 132 mEq/L. The patient denies recent antibiotic use. History reveals exposure to several pet turtles at home. Which of the following is the most likely pathogen?
Answer choices
- AChlamydophila psittaci
- BEntamoeba histolytica
- CStaphylococcus aureus
- DSalmonella enterica spp.Correct answer
- EYersinia enterocolitica
- FCampylobacter jejuni
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