Understanding and recognizing the Pelger-Huët anomaly.

The Pelger-Huët anomaly (PHA) is a recognized morphologic variant affecting all granulocytes but is most evident in polymorphonuclear neutrophils (PMNs). PHA is caused by a decreased amount of the lamin B receptor (LBR). Recognition of PHA morphologic features serves as a marker for mutations in the LBR gene. This review summarizes the history of PHA and the current knowledge of the functions of the LBR. Guidance is given for distinguishing PHA from other hematologic disorders in which granulocytes may show similar changes. Recognition of PHA in the laboratory should prompt communication to the patient's physician about the possible clinical significance of this finding and the recommended screening for the anomaly in other family members by CBC and review of a peripheral blood smear.