Pathology/Lab Coding Alert

Question: Sometimes we get cases with urine culture code 87086 along with 87186 done multiple times because they are testing for different microbiology susceptibility studies. Should I use modifier 91 or 59?

Iowa Subscriber

Answer: You should not need to use either modifier 91 (Repeat clinical diagnostic laboratory test) or 59 (Distinct procedural service) to report multiple units of 87186 (Susceptibility studies, antimicrobial agent; microdilution or agar dilution (minimum inhibitory concentration [MIC] or breakpoint), each multi-antimicrobial, per plate) for susceptibility studies for different organisms isolated from the urine culture.

Code 87186 describes antimicrobial susceptibility testing for a single isolate from a culture (urine culture, in this case). Because urinary tract infections (UTIs) are often polymicrobial, isolating more than one organism from a urine culture would not be unusual. You may report one unit of 87186 for each isolate that your lab evaluates for susceptibility, which may result in multiple units of 87186.

Tip: You mentioned reporting 87086 (Culture, bacterial; quantitative colony count, urine) for your lab’s urine culture, but you should not forget to also report the culture isolation using 87088 (Culture, bacterial; with isolation and presumptive identification of each isolate, urine). In fact, if the urine culture results in the identification and colony count of multiple organisms, as you mentioned, you would also report multiple units of 87088 and 87086.

Caveat: If your payer indicates that you need to use a modifier such as 91 or 59 in these cases, you should comply with the payer’s instruction.