CPT code 0183U is a Proprietary Laboratory Analyses (PLA) code for the Navigator DI Sequencing test by Grifols Immunohematology Center that analyzes specific gene sequences to determine Diego (DI) blood group antigens; this molecular diagnostic test is used to help clinicians minimize adverse blood‑type incompatibility reactions in blood transfusion, organ transplant, and maternal‑newborn settings and is conducted as a targeted genetic sequencing laboratory service using a blood specimen in an outpatient or clinical laboratory setting.

For related coverage guidance, see recent payer policy updates: RTM Testing of Homocysteine Metabolism-Related Conditions, Multimarker Serum Testing Related to Ovarian Cancer, Genomic Profiling for Selecting Targeted Cancer Therapies.