CPT code 81374 designates a laboratory technical test for low- or intermediate-resolution assessment of human leukocyte antigen (HLA) genes for one Class I antigen equivalent. This HLA allele-group testing supports clinical decision-making in contexts such as transplant matching, disease association studies, and pharmacogenomic risk assessment. Nationally, standardized reporting of such molecular diagnostic services affects laboratory billing consistency and payer coverage policies for genetic testing.

Key payers relevant to this service include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the code’s clinical scope and typical sites of service, plus a summary of payer coverage considerations and common billing modifiers used with laboratory technical components. The publication outlines what to expect in coding and billing workflows, and provides context for how this test fits into broader genetic testing and transplant evaluation pathways.

This analysis is intended for a national audience and focuses on code definition, clinical context, and practical billing elements. Data not available in the input are explicitly noted where applicable.