A 35-year-old male presents with a painless genital ulcer followed by unilateral inguinal lymphadenopathy. Examination reveals enlarged lymph nodes above and below the inguinal ligament with a groove between them (groove sign). The causative organism is:

• A Chlamydia trachomatis serovars L1-L3 ✓
• B Treponema pallidum
• C Haemophilus ducreyi
• D Klebsiella granulomatis

Explanation

Lymphogranuloma venereum (LGV) is caused by the invasive serovars L1, L2, and L3 of Chlamydia trachomatis. The groove sign (sign of Greenblatt) — a groove running between the inguinal and femoral lymph node groups corresponding to Poupart's ligament — is characteristic, seen in about 20% of cases. The primary painless ulcer heals before inguinal lymphadenopathy appears, so the patient may not recall it. Doxycycline for 21 days is the treatment. Treponema pallidum causes syphilis with firm painless chancre; H. ducreyi causes painful chancroid; Klebsiella granulomatis causes donovanosis.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.