CPT® Code 81431

Hearing loss (eg, nonsyndromic hearing loss, Usher syndrome, Pendred syndrome); duplication/deletion analysis panel, must include copy number analyses for STRC and DFNB1 deletions in GJB2 and GJB6 genes

The CPT® Code 81431 pertains to molecular genetic testing specifically aimed at identifying genetic factors associated with hearing loss (HL). This testing is crucial for diagnosing various forms of HL, including nonsyndromic hearing loss, which occurs without any visible anomalies, and syndromic hearing loss, such as that seen in Usher syndrome and Pendred syndrome, which may involve malformations of the external ear or other organs. The identification of genetic variants through this testing can provide valuable insights into the underlying causes of HL in both children and adults, thereby assisting otologists in determining appropriate treatment options. Hearing loss can manifest in several forms: conductive, sensorineural, mixed, or central. Conductive HL is characterized by anomalies in the external ear or the ossicles of the middle ear, while sensorineural HL is associated with malformations of the inner ear or cochlea. Mixed HL combines elements of both conductive and sensorineural types, and central HL results from damage or dysfunction in the auditory pathways, including the 8th cranial nerve, auditory brain stem, or cerebral cortex. The genetic loci commonly linked to hereditary HL include DFNA3 and DFNB1, with DFNA3 often resulting from an autosomal dominant mutation in the GJB2 or GJB6 genes, and DFNB1 typically arising from an autosomal recessive mutation in the GJB2 gene. Notably, pathogenic copy number variants (CNVs) associated with HL can include insertions, deletions, or recombinations, with the STRC gene being a significant contributor to autosomal recessive HL. The testing process involves analyzing DNA extracted from a blood sample using next-generation sequencing techniques, which allows for comprehensive evaluation of the genetic factors involved in hearing loss.