Reflexed Manual Differentials

At the April 25, 2005 Lab Open Door Forum CMS noted that the following guidance in the current National Correct Coding Policy Manual, Chap. 10, Pathology/Laboratory Services essentially prohibits billing for a reflexed manual WBC differential performed as a result of an abnormal or flagged automated WBC differential.

“If, after a test is ordered and performed, additional related procedures are necessary to provide or confirm the result, these would be considered part of the ordered test. For example, if a patient with leukemia has a thrombocytopenia, and a manual platelet count (CPT 85032) is performed in addition to the performance of an automated hemogram with automated platelet count (85027), it would be inappropriate to report codes 85032 and 85027 because the former provides a confirmatory test for the automated hemogram and platelet count (85027). As another example, if a patient has an abnormal test result and repeat performance of the test is done to verify the result, the test is reported as one unit of service rather than two.”

Based on this new guidance, a CBC and manual WBC differential may only be billed together when a physician specifically orders a CBC without automated WBC differential (85027) and a manual WBC differential (85007). In this case, CPT code 85027 and 85007 would be reimbursed. CCI edits prohibit the combination of 85007 and 85025 (CBC with automated WBC differential) based on the fact that the manual WBC duplicates the automated WBC differential included in 85025.