Bacterial Infections USMLE Step 1 Practice Question
A 25 year old man presents with dysuria and urethral discharge 1 week after unprotected intercourse. Nucleic acid amplification testing for Neisseria gonorrhoeae and Chlamydia trachomatis is negative. Gram stain of the urethral exudate shows neutrophils but no visible organisms. The causative organism is urease positive and lacks a cell wall. Which of the following is the most likely causal organism?
Answer choices
- ATreponema pallidum
- BChlamydia trachomatis
- CMycoplasma pneumoniae
- DEnterococcus faecalis
- EUreaplasma urealyticumCorrect answer
- FTrichomonas vaginalis
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