A 32-year-old man from Chennai presents with a small, painless ulcer on the coronal sulcus noted 2 weeks ago, which he initially ignored. He now complains of severe inguinal pain and swelling for the past 5 days. On examination, the primary ulcer is small and shallow with clean margins; inguinal lymph nodes are matted, tender, and show signs of coalescence. Serological testing is positive for *Chlamydia trachomatis* L2. What is the most appropriate next step in management?

Explanation

## Diagnosis and Management: Lymphogranuloma Venereum (LGV) **Key Point:** LGV is caused by *Chlamydia trachomatis* serovars L1, L2, and L3. The diagnosis is confirmed by serology and/or PCR, and treatment requires prolonged doxycycline therapy, not single-dose regimens. ### Clinical Presentation of LGV **Stage 1 (Primary):** Small, painless ulcer at site of inoculation (often overlooked) - Incubation: 3–30 days (average 10–14 days) - Ulcer: Shallow, painless, clean margins - Heals spontaneously even without treatment **Stage 2 (Secondary):** Painful inguinal lymphadenopathy (2–6 weeks post-exposure) - Matted, tender lymph nodes - May suppurate and form sinuses - Systemic symptoms: fever, malaise - **This patient is in Stage 2** **Stage 3 (Tertiary):** Chronic sequelae (months to years) - Rectal strictures, fistulae - Genital elephantiasis - Fibrosis and scarring ### Treatment Comparison | Antibiotic | Dose | Duration | Indication | Notes | |------------|------|----------|------------|-------| | **Doxycycline** | 100 mg BD | **21 days** | **LGV (all stages)** | **First-line for LGV** | | Azithromycin | 1 g single | 1 dose | Uncomplicated urethritis/cervicitis | Inadequate for LGV; requires prolonged therapy | | Ceftriaxone | 250 mg IM | 1 dose | Gonorrhoea | Not effective for LGV | | Erythromycin | 500 mg QID | 21 days | Alternative (pregnancy) | Less preferred; GI side effects | **High-Yield:** LGV is the ONLY STI ulcer that requires **prolonged (21-day) antibiotic therapy**. Single-dose regimens are inadequate and risk treatment failure and progression to Stage 3. **Clinical Pearl:** The serological positivity for *C. trachomatis* L2 (a serovariable) is diagnostic. PCR of ulcer exudate or lymph node aspirate would also confirm the diagnosis. ### Why Surgical Drainage Is NOT First-Line - Drainage is reserved for **fluctuant buboes that do not respond to antibiotics** (typically after 1–2 weeks of therapy) - Early drainage risks fistula formation and poor healing - This patient should receive antibiotics first **Mnemonic:** **LGV = Long therapy** (21 days of doxycycline) [cite:Harrison 21e Ch 187; Park 26e Ch 10]