A 7-year-old girl from rural Rajasthan presents with recurrent purulent eye discharge and mild photophobia for the past 3 months. On examination, she has bilateral conjunctival injection, upper tarsal papillae, and a few small white dots on the upper tarsal conjunctiva. Her younger sibling has similar symptoms. The girl attends a school with poor sanitation. What is the most likely diagnosis?

## Clinical Diagnosis: Active Trachoma (TF Stage) ### Key Clinical Features **Key Point:** The combination of recurrent purulent discharge, bilateral involvement, upper tarsal papillae, and white dots (Arlt's line/follicles) in a child from a rural, low-sanitation setting is pathognomonic for active trachoma. ### Trachoma Classification (Simplified WHO Grading) | Stage | Abbreviation | Key Features | |-------|--------------|---------------| | **Trachomatous Inflammation-Follicular** | **TF** | ≥5 follicles on upper tarsal conjunctiva; active infection; child <5 years | | **Trachomatous Inflammation-Intense** | **TI** | Intense papillary inflammation obscuring vessels; active disease | | **Trachomatous Trichiasis** | **TT** | ≥1 inturned eyelash; scarring phase | | **Trachomatous Corneal Opacity** | **CO** | Corneal scarring/opacity; blindness risk | **High-Yield:** Active trachoma (TF/TI) is caused by *Chlamydia trachomatis* serovars A, B, Ba, and C. The disease is endemic in areas with poor water access and sanitation. ### Pathognomonic Findings in This Case 1. **Upper tarsal papillae + white dots** → Follicles (inflammatory response to chlamydial antigen) 2. **Bilateral involvement** → Typical of trachoma; often affects entire household 3. **Age 7 years + rural setting** → Peak prevalence in children <5–10 years in endemic areas 4. **Sibling involvement** → Household transmission via contaminated fingers, fomites, and flies 5. **Recurrent discharge** → Chronic/recurrent infection if untreated ### Diagnostic Confirmation **Clinical Pearl:** Diagnosis is primarily clinical in endemic areas. Giemsa-stained conjunctival smear may show intracytoplasmic inclusion bodies (Halberstaedter–Prowazek bodies), but PCR/nucleic acid amplification is gold standard. ### Management Principles - **Antibiotics:** Azithromycin 20 mg/kg once weekly × 3 weeks (or single-dose 20 mg/kg) for active disease - **Hygiene:** Face washing, water access, sanitation improvement (A, F, E strategy) - **Surgery:** Reserved for trichiasis (TT) and corneal opacity (CO) stages **Mnemonic: SAFE Strategy for Trachoma Control** — **S**urgery (for trichiasis), **A**ntibiotics (azithromycin for active infection), **F**acial cleanliness, **E**nvironmental improvement (water, sanitation). ### Why This Is NOT the Other Options - **Acute bacterial conjunctivitis:** Unilateral or bilateral acute onset, responds to topical antibiotics in days; no tarsal papillae or follicles; no household clustering - **Viral keratoconjunctivitis:** Preauricular lymphadenopathy, photophobia more prominent, keratitis common; follicles are smaller and less organized - **Allergic conjunctivitis:** Giant papillae (>1 mm), seasonal variation, pruritus dominant, no purulent discharge, no systemic transmission [cite:Park 26e Ch 12, Ophthalmology NEET PG standard references]