A 35-year-old woman from Mumbai with a 6-month history of recurrent painful oral ulcers and genital ulceration presents with acute loss of vision in the left eye over 3 days. On examination, visual acuity is hand motions. Slit-lamp shows severe anterior chamber reaction (4+ cells), fibrin, and posterior synechiae. Fundoscopy reveals dense vitritis with hemorrhage obscuring the disc, and multiple retinal infiltrates with vasculitis. B-scan ultrasonography confirms severe vitritis. Serum HLA-B51 is positive. What is the most appropriate initial management?

Explanation

## Diagnosis: Behçet's Disease with Posterior Uveitis ### Clinical Recognition **Key Point:** The **pathognomonic triad** of recurrent **oral ulcers**, **genital ulceration**, and **ocular involvement** (uveitis) with **positive HLA-B51** is diagnostic of **Behçet's disease**. The **severe vitritis hemorrhage, retinal infiltrates, and vasculitis** indicate **posterior segment involvement**, which carries a poor visual prognosis if untreated. ### Why Systemic Corticosteroids + Immunosuppressants? | Feature | Topical Only | IV Methylpred + Oral + IS | Intravitreal Injection | Antibiotics | |---------|--------------|--------------------------|------------------------|-------------| | **Penetrates posterior segment** | ✗ (poor) | ✓ (excellent) | ✓ (local) | ✗ | | **Treats systemic inflammation** | ✗ | ✓ | ✗ | ✗ | | **Prevents recurrence** | ✗ | ✓ | ✗ | ✗ | | **Indicated for severe vitritis** | ✗ | ✓ | Adjunct only | ✗ | | **Prevents blindness** | ✗ | ✓ | Partial | ✗ | **High-Yield:** Behçet's uveitis is **aggressive and vision-threatening**. Posterior involvement requires **systemic immunosuppression**, not just topical therapy. ### Treatment Algorithm ```mermaid flowchart TD A["Behçet's disease with severe posterior uveitis"]:::outcome --> B{"Severity?"}:::decision B -->|"Mild anterior only"| C["Topical corticosteroids"]:::action B -->|"Moderate-severe or posterior"| D["IV Methylprednisolone 500-1000 mg daily × 3 days"]:::action D --> E["Transition to oral prednisolone 1 mg/kg/day"]:::action E --> F["Add immunosuppressants at 2-4 weeks"]:::action F --> G["Azathioprine OR Mycophenolate OR Infliximab"]:::action G --> H["Taper corticosteroids over 3-6 months"]:::action H --> I["Long-term immunosuppression to prevent recurrence"]:::outcome ``` ### Rationale for IV Methylprednisolone 1. **Severe vitritis hemorrhage** → requires rapid anti-inflammatory effect 2. **Retinal vasculitis** → risk of retinal necrosis and optic atrophy 3. **Posterior segment involvement** → topical agents cannot achieve therapeutic intraocular levels 4. **Aggressive course of Behçet's** → early high-dose therapy prevents permanent vision loss **Clinical Pearl:** Behçet's-associated uveitis is one of the **most vision-threatening forms of uveitis**. Without aggressive systemic treatment, **50% of patients become blind within 5 years**. ### Immunosuppressive Agents in Behçet's **Mnemonic: AIM** — **Azathioprine, Infliximab, Mycophenolate** - **Azathioprine** (1–2.5 mg/kg/day): First-line steroid-sparing agent; takes 8–12 weeks to work - **Mycophenolate mofetil** (1–3 g/day): Effective alternative; faster onset than azathioprine - **Infliximab** (TNF-α inhibitor): Reserved for refractory cases; highly effective but expensive - **Cyclosporine**: Avoid in Behçet's (may worsen posterior segment disease) ### Follow-up and Monitoring - **Ophthalmology review** at 1 week, then 2–4 weeks - **Fundus examination** as vitritis clears (B-scan if needed) - **Monitor for steroid side effects** (hyperglycemia, hypertension, osteoporosis) - **Baseline TB screening** before starting immunosuppressants - **Long-term immunosuppression** (2–5 years) to prevent recurrence