Blebitis

Glaucoma filtering bleb infection demonstrating milky-appearing ischemic bleb surrounded by intense conjunctival hyperemia. 

  • An uncommon but significant early- to late-onset complication of glaucoma filtering surgery.

Risk factors:

  • Full thickness filtering surgery
  • Use of antifibrotic agents such as 5-fluorouracil (5-FU) and mitomycin-C (MMC)
  • Late-onset filtering bleb leakage
  • Inferior location of the filtering bleb
  • Blepharitis or ocular surface disease

Clinical features:

  • Symptoms: pain and/or red eye (either sudden or sub-acute), decreased vision, ocular irritation, light sensitivity
  • Signs:
    • Milky-appearing ischemic bleb surrounded by intense conjunctival hyperemia
    • Anterior chamber inflammatory reaction
    • Mucopurulent infiltrate within the bleb
    • Mild to moderate anterior segment inflammation
    • Hypotony if associated with bleb leakage
  • May be complicated with full-blown endophthalmitis

Management:

  • Workup: 
    • Culture bleb with conjunctival swab (and anterior chamber tap for more severe infection)
    • B-scan ultrasound to rule out posterior segment involvement
  • Mild to moderate infection: 
    • Intensive topical antibiotics 
    • Topical steroids when appropriate
    • Cycloplegics if indicated
    • Frequent follow-up (often daily)
  • Severe infection
    • Hospitalization
    • Intravenous antibiotic therapy
    • Hourly topical fortified antibiotics
    • Cycloplegicss
    • Topical or intravitreal steroids
    • Vitrectomy in cases of worsening despite aggressive therapy
  • Visual prognosis is good with prompt and aggressive therapy