Pathology/Lab Coding Alert

Question: Our lab identified Proteus rettgeri from a wound culture, and performed susceptibility testing by the MIC method using a Vitek-2 autoanalyzer. How should we code the service?

Idaho Subscriber

Answer: Whether you use a microbiology analyzer such as the Vitek 2 that combines several steps, or more traditional microbiology methods, you should report each step that your lab performs for a given culture.

You might have a code for one or more of the following steps:

- culture and presumptive identification (first step for most cultures)

- definitive identification (to the species level)

- culture typing (such as different strains of a species)

- susceptibility studies.

Although the Vitek 2 can combine the definitive identification and minimum inhibitory concentration (MIC) steps on a single plate, you should still code each billable step of the combined analysis.

In your example, the correct codes are as follows:

- 87070 -- Culture, bacterial; any other source except urine, blood or stool, aerobic, with isolation and presumptive identification of isolates

- 87077-- Culture, bacterial; aerobic isolate, additional methods required for definitive identification, each isolate

- 87186 -- Susceptibility studies, antimicrobial agent; microdilution or agar dilution (minimum inhibitory concentration [MIC] or breakpoint), each multi-antimicrobial, per plate.

Caution: Make sure you select billable codes based on the guidelines for additional studies at the beginning of the CPT microbiology section just before 87001.