Pathology/Lab Coding Alert

Question: Sometimes, the transplant/stem cell physicians at our hospital send us two samples from the same apheresis patient collected at different times during the day to monitor CD34/CD3 counts. We use flow cytometry to provide the cell counts, but we're performing each of the tests twice in the same day. How should we report this service?


Ohio Subscriber

Answer: Although the lab uses flow cytometry for these cell counts, you should not report the service with flow cytometry codes 88184-88189. CPT reserves these codes for panels that require pathologist interpretation, such as immunophenotyping of potential hemato-lymphoid neoplasms.
 
Rather, you should use the total-cell-count codes in the immunology section. For the stem cell count, report 86587 (Stem cells [i.e., CD34], total count). For CD3, use 86359 (T cells; total count). 

Because your lab repeats the same tests for the patient from a specimen collected later in the day, you should report the later tests using the same codes, but add modifier 91 (Repeat clinical diagnostic laboratory test).