CPT code 0522U designates a Proprietary Laboratory Analyses (PLA) blood test from KSL Diagnostics Inc. that targets tissue-specific antibodies — carbonic anhydrase VI, parotid-specific protein, and salivary protein 1 (SP1) — using chemiluminescence to support early diagnosis of Sjögren’s disease. As a PLA code, 0522U applies only to this unique test and signals growing use of proprietary molecular diagnostics in autoimmune disease evaluation.

Key national payers discussed include Aetna, Blue Cross Blue Shield, Cigna, UnitedHealthcare, and Medicare. Coverage and reimbursement approaches for PLA tests vary across payers, with implications for lab adoption and clinician ordering patterns.

Readers will find a concise overview of the clinical purpose and service setting for the test, payer inclusion in the analysis, and the types of benchmarks and policy topics typically relevant to PLA codes — including coverage policies, coding guidance, and utilization context for early Sjögren’s diagnosis. The publication does not provide state-specific guidance and focuses on national relevance for payers, laboratorians, and clinical stakeholders.