DR10.3 | Non-Syphilitic Genital Ulcer Differential Diagnosis — Summary & Reflection

KEY TAKEAWAYS

Not every genital ulcer is syphilis, and the highest-yield first step is the painful-versus-painless triage. The painful ulcers are chancroid (Haemophilus ducreyi — a painful, soft, ragged, undermined ulcer with a tender suppurative bubo; school-of-fish Gram-negative coccobacilli on a Gram stain of ~50% sensitivity) and herpes genitalis (HSV-2 — painful grouped vesicles becoming shallow ulcers, recurrent, with multinucleated giant cells on a Tzanck smear that are not HSV-specific, PCR being the gold standard). The painless ulcers include the syphilitic chancre, LGV (C. trachomatis L1–L3, with groove-sign lymphadenopathy), and donovanosis (Klebsiella granulomatis, a beefy-red friable ulcer with Donovan bodies on Giemsa smear). Treatment follows mechanism: chancroid responds to single-dose azithromycin or ceftriaxone (aspirate, never incise, a bubo), while herpes is controlled with acyclovir and, for frequent recurrences, suppressive therapy. Syndromically, herpetic ulcers receive NACO Kit 4 (blue) and non-herpetic ulcers Kit 3 (white), per current NACO guidance, with HIV testing and partner management throughout.

REFLECT

Think back to the two men in the opening scenario, separated by nothing more than whether their ulcer hurt. How confident are you that, faced with a real ulcer, you would ask about pain, texture, and recurrence before reaching for any test — and what would you do differently if no laboratory were available that day? Now consider the patient with recurrent painful genital herpes who is distressed by how often it returns: how would you explain that the virus lives latent in his nerve roots, that you cannot cure it but can suppress it, and that he can still transmit it between attacks? Rehearsing both the diagnostic reasoning and this difficult conversation prepares you for the genital ulcer as patients actually present it.