Below is a list summarizing the CPT codes for antimicrobial susceptibility studies.
CPT Code 87181
CPT 87181 describes susceptibility studies using the agar dilution method for an antimicrobial agent, such as an antibiotic gradient strip.
CPT Code 87184
CPT 87184 describes susceptibility studies using the disk method per plate for 12 or fewer antimicrobial agents.
CPT Code 87185
CPT 87185 describes susceptibility studies and detection of an antimicrobial agent’s enzyme (e.g., beta-lactamase) per enzyme.
CPT Code 87186
CPT 87186 describes susceptibility studies, including antimicrobial agent microdilution or agar dilution (minimum inhibitory concentration [MIC] or breakpoint) for each multi-antimicrobial per plate.
CPT Code 87188
CPT 87188 describes susceptibility studies using the macrobroth dilution method for each antimicrobial agent.
CPT Code 87190
CPT 87190 describes susceptibility studies for antimicrobial agents against mycobacteria using the proportion method for each agent.
CPT Code 87197
CPT 87197 describes the Schlichter test for measuring serum bactericidal titer.