Attenuated Chédiak-Higashi Syndrome

A very rare and atypical form of Chédiak-Higashi syndrome (CHS), a genetic disorder characterized by partial oculocutaneous albinism, severe immunodeficiency, mild bleeding, neurological dysfunction and lymphoproliferative disorder.

Epidemiology

Fewer than 100 cases have been reported to date but the disorder is likely underdiagnosed. The atypical form may account for 10-15% of CHS patients who do not develop the accelerated phase.

Clinical description

Mild adolescent- or adult-onset attenuated CHS is characterized by subtle or absent oculocutaneous albinism, a characteristic feature of classic CHS, as well as minor to severe infections during childhood but a lower frequency of infections in adolescence and adulthood, mild bleeding manifestations, and progressive neurological findings including intellectual deficit, peripheral neuropathy, parkinsonism, balance abnormalities, and tremor.

Etiology

Missense mutations in the LYST lysosomal trafficking regulator gene (1q42.1-q42.2) appear to cause this form of CHS.

Genetic counseling

Attenuated Chédiak-Higashi syndrome is inherited in an autosomal recessive manner.