A sexually active 25-year-old man develops epididymitis and orchitis. Needle biopsy demonstrates a prominent leukocytic infiltrate with numerous neutrophils. Which of the following organisms is the most likely cause of this man's infection?
High-Yield Explanation
Acute epididymitis and orchitis with prominent neutrophils in a sexually active male are most likely due to infection with Neisseria gonorrhoeae or Chlamydia trachomatis. N. gonorrhoeae can produce a nonspecific pattern of acute inflammation (nonspecific epididymitis and orchitis) or can be sufficiently severe as to cause frank abscesses within the epididymis. Escherichia coli is an impoant cause of nonspecific epididymitis and orchitis in children with congenital genitourinary abnormalities and in older men. Mycobacterium tuberculosis can cause tuberculosis of the epididymis and testes, characterized by granuloma formation. Pseudomonas sp. has been implicated as an impoant cause of nonspecific epididymitis and orchitis in older men. Ref: Levinson W. (2012). Pa IX. Brief Summaries of Medically Impoant Organisms. In W. Levinson (Ed), Review of Medical Microbiology & Immunology, 12e.