Pembrolizumab-induced Cogan-like syndrome in a patient with renal carcinoma: a case report

Síndrome de Cogan-like inducido por pembrolizumab en paciente con carcinoma renal: reporte de caso

Introduction: Cogan-like syndrome is a rare inflammatory disorder characterized by ocular and auditory involvement, whose association with immune checkpoint inhibitors is exceptional and poses diagnostic and therapeutic challenges.

Clinical case:  We report the case of a 54-year-old male with stage IV clear cell renal carcinoma treated with pembrolizumab, who, after the tenth dose, developed bilateral uveitis, optic neuritis, sensorineural hearing loss, tinnitus, and vertigo, progressing to functional blindness and deafness. Imaging studies excluded tumoral and infectious involvement. Immunotherapy was discontinued, and multidisciplinary management was initiated with intravenous corticosteroid pulses followed by oral prednisone and azathioprine. The temporal evolution and exclusion of alternative diagnoses supported the diagnosis of pembrolizumab-induced Cogan-like syndrome, a condition described in very few reports, mostly associated with nivolumab and frequently with irreversible outcomes.

Conclusion: This case highlights the importance of early recognition, prompt drug discontinuation, and timely initiation of immunosuppressive therapy, considering Cogan-like syndrome as a late-onset immune-related adverse event (after the tenth dose, approximately 9–10 months of therapy), in which multidisciplinary intervention is essential to reduce the risk of permanent sequelae.