Bacterial Infections USMLE Step 1 Practice Question
A 29 year old man presents with a painless penile ulcer that appeared 10 days ago. He reports unprotected intercourse with a new partner 4 weeks earlier. Examination shows a clean based indurated chancre and nontender inguinal lymphadenopathy. Darkfield microscopy of lesion exudate reveals corkscrew shaped organisms. Which of the following is the most likely diagnosis?
Answer choices
- AGenital herpes due to HSV 2
- BGranuloma inguinale due to Klebsiella granulomatis
- CLymphogranuloma venereum due to Chlamydia trachomatis
- DChancroid due to Haemophilus ducreyi
- EPrimary syphilis due to Treponema pallidumCorrect answer
- FDonovanosis due to Calymmatobacterium donovani
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