Chediak-Higashi syndrome is a rare childhood autosomal recessive disorder that affects multiple systems of the body. The underlying defect in Chediak-Higashi syndrome remains elusive, but the disorder can be considered a model for defects in vesicle formation, fusion, or trafficking.
The Chediak-Higashi syndrome locus on human chromosome 1 encodes a lysosomal trafficking regulator, formerly termed LYST (currently termed CHS1), which is defective in patients with CHS.
The CHS protein is expressed in the cytoplasm of cells of a variety of tissues. Defects in CHS protein may cause an abnormality of organellar protein trafficking.
Hence Patients with Chediak-Higashi syndrome exhibit alterations in neutrophils. These alterations include neutropenia, which may be profound; decreased deformability, resulting in impaired chemotaxis; and delayed phagolysosomal fusion. This results in impaired bactericidal activity.
The disease is often fatal in childhood as a result of infection or an accelerated lymphoma like phase; therefore, few patients live to adulthood. Recurrent bacterial infections, partial albinism, and aggressive but non malignant infiltration of organs by lymphoid cells are common in this disease.
Phagocytes of the patient show giant granules formed by ingested pathogens, as they lost ability of killing the engulfed pathogen.