CPT code 86581 represents a laboratory-performed, quantitative multiplex immunoassay for detection of Streptococcus pneumoniae antibodies, reported by serotype. The code captures serologic evaluation used in clinical assessment of immune response to pneumococcal exposure or vaccination and has relevance for infectious disease management, vaccine response monitoring, and epidemiologic surveillance. Nationally, such serotype-specific testing informs clinical decisions in immunocompromised patients and supports public health efforts to track serotype prevalence.

Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an overview of clinical context for serotype-specific pneumococcal antibody testing, typical sites of service, commonly used modifiers, and payers' coverage considerations where available. The publication outlines benchmarks and utilization context when data is present and notes where information is not available in the input.

This summary provides clinicians, laboratory managers, and billing professionals with a concise reference to CPT code 86581, clarifying the service captured by the code and the primary clinical scenarios in which quantitative multiplex pneumococcal serology is used.