Abstract
Progressive unilateral hearing loss (PUHL) in adolescents is uncommon and presents diagnostic challenges due to its varied etiologies, including infections, ototoxicity, congenital anomalies, and autoimmune conditions, though many cases remain idiopathic. We report a 16-year-old male with a history of COVID-19, dengue at age 14, and recurrent headaches, who developed left-sided hearing loss progressing to profound unilateral deafness. Audiometry confirmed sensorineural hearing loss (SNHL) of 97 dB HL in the left ear and 35 dB HL in the right. Despite multiple evaluations, no definitive etiology was identified. Differential diagnoses included post-viral sequelae, congenital anomalies (e.g., Mondini dysplasia), and nasal obstruction, though insurance limitations restricted further testing. The patient discontinued hearing aid use due to limited benefit and experienced social withdrawal, impacting both academic performance and overall well-being. This case underscores the importance of early recognition and a systematic, multidisciplinary approach to PUHL, including imaging and genetic testing, given its potential impact on social development, mental health, and long-term outcomes.