Basophil counts are performed differently on different analyzers, but all have some possible inherent inaccuracies. However, overestimation (as in this case) tends to be more likely than underestimation on most analyzers. Three possible causes of spuriously elevated basophil counts include:
- Delayed processing greater than 24 hours may result in an erroneously high basophil count.
- In analyzers utilizing a basophil-specific channel, separation from the other WBCs depends on them resisting lysis. However, other cells can sometimes resist lysis, such as reactive lymphocytes, lymphoma cells, and blasts.
- In analyzers that utilize a common WBC channel, other cells such as degranulated neutrophils, nucleated RBCs, and platelet clumps can be erroneously counted.
Other more esoteric factors can come into play and depend specifically on the type of analyzer and the possible presence of other abnormal cells in the patient's blood.
