Atypical Presentation of Late-Onset Toxic Anterior Segment Syndrome Following Cataract Surgery: Challenges in Diagnosis and Management.

Toxic anterior segment syndrome (TASS) is a rare, non-infectious inflammatory response following anterior segment surgery that can be challenging to distinguish from infectious endophthalmitis, which requires different treatments. This case report describes a 72-year-old male with controlled hypertension, diabetes, and hyperlipidemia who developed an atypical presentation of TASS following uncomplicated cataract surgery. On postoperative day 7, the patient exhibited significant visual decline and anterior segment inflammation, raising concern for endophthalmitis. Diagnostic challenges included the absence of pain, delayed symptom onset, and vitritis. Treatment with intravitreal corticosteroids and antibiotics led to gradual visual recovery, with final visual acuity of 20/20 by day 30. No specific causative agent for TASS was identified, but the case highlights the importance of early recognition and management, as well as the potential contribution of surgical equipment issues and systemic risk factors in TASS development.