An Atypical Case of Severe Toxicity, Anterior Chamber Inflammation, and Transient Subretinal Fluid Formation Induced by the Subconjunctival Injection of 5-FU.

Purpose: To report an atypical presentation of severe toxicity, anterior chamber (AC) inflammation, and transient parafoveal formation of subretinal fluid induced by the subconjunctival injection of 5-fluorouracil (5-FU).

Methods: Case presentation.

Results: Seven weeks after trabeculectomy, a 40-year-old white male had a subconjunctival injection of 5-FU. Within minutes after the injection, the lens turned grey and then total white. Initially, AC was clear, and 20 min later, a severe AC reaction was detected. The patient was prescribed hourly dexamethasone eye drops and tropicamide eye drops twice daily. Two days post-injection, vision improved, AC reaction was minimal, and there was whitish fibrinous material on the anterior surface of the lens, extending up to the pupillary margin. Minimal posterior synechiae were observed, and upon dilation, the remainder of the anterior surface of the lens appeared completely clear, indicating that only the portion of the lens not covered by the iris exhibited fibrinous material and deposits. One week post-injection, vision worsened due to severe corneal toxicity. The dimensions of the whitish fibrinous material on the anterior lens capsule decreased, and macular scans revealed parafoveal subretinal fluid. Two weeks later, vision significantly improved, and the dimensions of the whitish fibrinous material on the anterior lens capsule were further decreased. The subretinal fluid had completely resolved.

Conclusion: We describe a rare case of severe toxicity, AC inflammation, and transient parafoveal subretinal fluid formation caused by the 5-FU. This was treated with topical steroid treatment, and eventually some level of lens opacification persisted despite significant clearance of the AC inflammation.