Complete Labyrinthine Aplasia: A Unique Sign for Targeted Genetic Testing in Hearing Loss

Complete labyrinthine aplasia (CLA) is a rare inner ear anomaly. The only identified genetic cause of CLA with severe sensorineural hearing loss is labyrinthine aplasia, microtia, and microdontia (LAMM) syndrome. Here we reported a child who presented with syndromic hearing loss and was diagnosed with LAMM syndrome. Genetic evaluation provided the family with confirmation of the diagnosis, provision of the prognosis, genetic counselling, and prenatal diagnosis. This report highlighted that CLA should be recognized as a unique sign to diagnose LAMM syndrome, to analyze FGF3 gene mutation, and also demonstrated the utility of genetic testing in patients with suspected LAMM syndrome to provide exact diagnosis and further management.