PURPOSE OF REVIEW: WHIM syndrome (the association of warts, 
hypogammaglobulinemia, recurrent bacterial infections, and 'myelokathexis') is a 
rare congenital form of neutropenia associated with an unusual immune disorder 
involving hypogammaglonulinemia and abnormal susceptibility to warts. In this 
review, we describe the clinical, laboratory and genetic features of WHIM 
syndrome.
RECENT FINDINGS: The identification of chemokine receptor CXCR4 as the causative 
gene of WHIM syndrome yields new interest in the study of this disease as a 
model for the comprehension of CXCR4 biology in humans and highlights the 
importance of the chemokine network for inducing effective immune responses and 
governing leukocyte trafficking.
SUMMARY: CXCR4 participates in several biological processes (bone marrow 
hematopoiesis, cardiogenesis, angiogenesis, neurogenesis) and is implicated in 
different clinical pathologic conditions (WHIM, HIV infection, tumor 
metastatization, autoimmunity). Pharmacologic agents that modulate CXCR4 
expression/function are already available and promise a wide range of future 
clinical applications.