What is the recommended treatment for Posner‑Schlossman syndrome?

Posner-Schlossman Syndrome Treatment

For Posner-Schlossman syndrome (PSS), topical 2% ganciclovir combined with gradual steroid taper is the recommended first-line treatment, as cytomegalovirus (CMV) is the underlying cause in approximately 50% of cases.

Understanding PSS

PSS (glaucomatocyclitic crisis) is a unilateral condition causing recurrent attacks of mild anterior uveitis with marked intraocular pressure (IOP) elevation, predominantly affecting middle-aged males 1. The disease is strongly associated with CMV infection in the aqueous humor 2.

Diagnostic Approach

Key clinical features to identify:

• Iris depigmentation (present in 96% of CMV-positive cases)
• Coin-shaped keratic precipitates (KPs)
• Corneal endothelial cell loss (average 10.8%)
• Marked IOP elevation during attacks (often >40 mmHg)
• Minimal anterior chamber inflammation (mild or absent flare/cells)
• Preserved visual acuity initially 2, 3

Confirm CMV status through aqueous humor PCR testing when possible, as this guides treatment intensity 2.

Treatment Algorithm

Acute Attack Management

1. Topical 2% ganciclovir eye drops - 4 times daily 2

   • Addresses the underlying CMV infection
   • Reduces inflammation and IOP
   • Treatment duration: average 5-6 weeks initially

2. Topical corticosteroids - Start at moderate strength

   • Use the minimum effective dose
   • Begin tapering as inflammation resolves
   • Goal: complete withdrawal to avoid steroid dependency 4

3. IOP-lowering medications as needed

   • Beta-blockers, alpha-agonists, or carbonic anhydrase inhibitors
   • Taper as IOP normalizes with antiviral therapy

Expected Outcomes with Antiviral Therapy

After 5-6 weeks of topical ganciclovir 2:

• KPs decrease from 94% to 52% of cases
• Coin-shaped KPs nearly disappear (22% to 2%)
• Mean IOP drops from 26.2 mmHg to 15.5 mmHg
• 60% of patients can discontinue corticosteroids
• 65% of steroid-dependent patients achieve steroid withdrawal
• CMV DNA becomes undetectable in aqueous humor

Steroid-Dependent PSS

Critical pitfall: Approximately 27% of PSS patients develop steroid dependency (continuous use >3 months with relapse within 2 weeks of tapering) 4.

Risk factors for steroid dependency:

• Younger onset age
• Higher initial IOP
• Severe iris depigmentation
• Longer disease course

Management strategy for steroid-dependent cases:

• Initiate 2% ganciclovir with very gradual steroid taper
• This approach achieves steroid withdrawal in 66% of cases
• Another 32% can reduce steroid dose/strength
• Median stable time off steroids: 13 weeks 4

Surgical Intervention

Surgery becomes necessary when medical management fails. Indicators for surgical consideration 5, 6:

• High corneal endothelial cell density loss
• Maximum IOP persistently >40 mmHg despite medications
• Progressive visual field loss
• High CMV DNA copy numbers in aqueous humor
• Inability to control IOP with topical medications

Surgical options:

• Penetrating canaloplasty: 84.6% qualified success rate at 12 months, reduces attack frequency and severity 7
• Compound trabeculectomy: Effective for refractory cases with well-controlled IOP after 1 year 6

Long-term Monitoring

Monitor for:

• Recurrent attacks (69% recurrence rate even after surgery)
• Secondary glaucoma development (requires more aggressive treatment)
• Corneal endothelial cell loss (progressive)
• Steroid-induced ocular hypertension (occurs in 5.3% of PSS patients) 4

Common Pitfalls to Avoid

1. Misdiagnosis as acute angle-closure glaucoma - The marked IOP elevation can be misleading; check for open angles and mild inflammation 8
2. Prolonged steroid use without antiviral therapy - Creates steroid dependency and doesn't address underlying CMV infection
3. Inadequate steroid taper - Taper too quickly and attacks recur; too slowly and dependency develops
4. Delaying surgical intervention - Progressive endothelial cell loss and visual field damage are irreversible 5, 6