A 32-year-old Indian male presents with acute onset photophobia, pain, and blurred vision. Slit-lamp examination reveals granulomatous anterior uveitis with posterior synechiae. Chest X-ray shows bilateral hilar lymphadenopathy. What is the most common cause of anterior uveitis in this clinical presentation?

Explanation

## Most Common Cause of Granulomatous Anterior Uveitis with Bilateral Hilar Lymphadenopathy **Key Point:** The classic triad of **granulomatous anterior uveitis + bilateral hilar lymphadenopathy + young adult** is the hallmark presentation of **sarcoidosis**. While tuberculosis is common in India, the specific combination of bilateral hilar lymphadenopathy with granulomatous uveitis is the textbook presentation of sarcoidosis worldwide — and sarcoidosis is the most common systemic cause of uveitis associated with bilateral hilar lymphadenopathy even in Indian literature. **High-Yield:** Sarcoidosis accounts for approximately 5–10% of all uveitis cases globally and is the **most common cause of uveitis associated with bilateral hilar lymphadenopathy**. The stem's clinical picture — acute photophobia, granulomatous anterior uveitis with posterior synechiae, and bilateral hilar lymphadenopathy — is the prototypical sarcoid uveitis presentation as described in Kanski's Clinical Ophthalmology and Yanoff & Duker. ### Differential Diagnosis of Granulomatous Anterior Uveitis | Cause | Key Features | Systemic Findings | |-------|-------------|-------------------| | **Sarcoidosis** | Granulomatous AU, mutton-fat KPs, iris nodules, posterior synechiae | **Bilateral hilar lymphadenopathy**, hypercalcemia, elevated ACE, erythema nodosum | | Tuberculosis | Granulomatous AU, iris nodules, choroidal tubercles | Hilar lymphadenopathy (usually unilateral/asymmetric), Mantoux +ve, constitutional symptoms | | Syphilis | Granulomatous AU, "Koeppe nodules" | RPR/VDRL +ve, rash, generalised lymphadenopathy | | Leprosy | Granulomatous AU (rare) | Skin lesions, nerve thickening, positive slit-skin smear | **Clinical Pearl — Sarcoid Uveitis Features:** - Bilateral granulomatous anterior uveitis (most common ocular manifestation of sarcoidosis) - Large "mutton-fat" keratic precipitates - Iris nodules (Koeppe and Busacca nodules) - Posterior synechiae - Bilateral hilar lymphadenopathy on CXR (Löfgren syndrome variant) - Elevated serum ACE and lysozyme - Hypercalcemia, hypercalciuria **Why not Tuberculosis?** TB can cause granulomatous uveitis and hilar lymphadenopathy, but TB hilar lymphadenopathy is typically **unilateral or asymmetric**, whereas sarcoidosis classically produces **symmetric bilateral hilar lymphadenopathy**. The stem specifies bilateral hilar lymphadenopathy, which is the defining radiological feature of sarcoidosis (Kanski's Clinical Ophthalmology, 9th ed.; Harrison's Principles of Internal Medicine, 21st ed.). **Mnemonic — Sarcoidosis Ocular Features (BAGS):** Bilateral uveitis, ACE elevated, Granulomas (mutton-fat KPs), Synechiae posterior. **Reference:** Kanski's Clinical Ophthalmology (9th ed.) — Sarcoidosis is the most common systemic disease associated with bilateral granulomatous uveitis and bilateral hilar lymphadenopathy. Harrison's Internal Medicine (21st ed.) — Bilateral hilar lymphadenopathy is the radiological hallmark of sarcoidosis.