Pathogenic variants of the CXCR4 gene can result in the retention of white blood cells in the bone marrow.1
![WHIM MOA Graphic](/wp-content/uploads/2024/06/CXCR4-Pathway-Dysregulation-1.png)
![](/wp-content/uploads/2024/06/CXCR4-Pathway-Dysregulation-1.png)
Myelokathexis, the abnormal retention of neutrophils in the bone marrow, is a hallmark feature of WHIM syndrome, present in ~100% of cases. It is detected by bone marrow biopsy but can be challenging to identify and may be missed on initial biopsy evaluation.1,3-6
Bone Marrow Aspirates of WHIM Syndrome Patients Showing Key Pathological Features of Myelokathexis*,†,2,6
![WHIM Myelokathexis Biopsy Image](/wp-content/uploads/2023/12/MYELO-IMAGES-c-v2.png)
![](/wp-content/uploads/2023/12/MYELO-IMAGES-c-v2.png)