Summary & Overview
CPT 87188: Antimicrobial Susceptibility Testing by Macrobroth Dilution
Headline: CPT code 87188: Macrobroth Dilution Antimicrobial Susceptibility Testing
Lead: CPT code 87188 identifies the technical laboratory procedure for assessing a culture isolate’s susceptibility to multiple antimicrobial agents using macrobroth dilution techniques. This test supports targeted antibiotic selection and informs infection control and stewardship programs across clinical settings.
What this code represents and why it matters: CPT code 87188 covers the laboratory-based, technical component of antimicrobial susceptibility testing performed by a lab analyst using macrobroth dilution methods. As bacterial resistance patterns evolve, standardized susceptibility testing remains essential for appropriate antimicrobial therapy, public health surveillance, and stewardship efforts nationwide.
Key payers covered: Analysis addresses major national payers, including Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.
What readers will learn: The publication provides benchmarks and clinical context for CPT code 87188, outlines typical sites of service and service type, and summarizes common payer considerations. It highlights how the procedure fits into laboratory workflows and clinical decision-making. Policy or coding updates and payer-specific coverage patterns are summarized where available. Data not available in the input are noted when applicable.
Billing Code Overview
CPT code 87188 describes a laboratory service in which a lab analyst performs the technical steps to determine an isolate’s antimicrobial susceptibility using macrobroth dilution methods. The procedure evaluates a culture isolate’s growth in varying concentrations of multiple antimicrobial agents to identify which antibiotics inhibit or permit growth.
Service Type: Antimicrobial susceptibility testing (macrobroth dilution), technical component
Typical Site of Service: Clinical microbiology laboratory or hospital laboratory
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A hospitalized adult with suspected bloodstream infection has a positive blood culture that grows a bacterial isolate. The microbiology laboratory receives the isolate and performs identification and antimicrobial susceptibility testing by macrobroth dilution to determine minimum inhibitory concentrations for multiple antibiotics. The workflow: clinical team submits blood cultures; on growth, lab technologist isolates organism on media and performs identification (e.g., MALDI-TOF or biochemical methods). A laboratory analyst then performs the technical macrobroth dilution steps, incubates isolates in graded antibiotic concentrations, reads growth endpoints, and reports susceptibility results to the clinical team to guide targeted antimicrobial therapy. Typical site of service is the hospital microbiology laboratory or independent clinical laboratory supporting inpatient and outpatient facilities. The patient scenario often involves sepsis, bacteremia, complicated urinary tract infection, pneumonia, or postoperative wound infection where targeted therapy depends on susceptibility patterns. Turnaround time is generally 24–72 hours after isolate recovery depending on organism and test complexity.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when reporting only the professional interpretation component of a test if applicable for a lab that provides interpretation separate from the technical service. |