Syndrome Griselli (Griscelli syndrome)

Gricelli's syndrome is a congenital autosomal recessive syndrome, which is a combination of immunodeficiency and partial albinism, first described in France by Claude Griscelli. Albinism in this syndrome is caused by a violation of migration of melanosomes from melanocytes (in which a pigment is formed) into keratocytes. Two genes have been identified, the defect of which leads to the formation of the Gricelli phenotype: the Myosin 5a gene and the Rab gene 27a. The products of these genes are proteins involved in the transport of melanosomes and secretory granules of cytotoxic lymphocytes to the cell surface.

Gricelli's syndrome differs from the Chediak-Higashi syndrome by the absence of giant granules in the leukocytes. Before the detection of a specific genetic defect, the characteristic distribution of melanin in hair follicles, being pathognomonic, served as the basis for diagnosis of the syndrome. Patients are predisposed to fungal, viral and bacterial infections. Immunodeficiency can manifest as a decrease in the level of immunoglobulins, and a violation of cellular immunity, in particular, a violation of T-cell cytotoxicity and a decrease in the function of NK cells. The majority of patients develop a phase of lympho-histiocytic acceleration, similar to that in the Chediak-Higashi syndrome, and requires induction of remission. The only radical treatment for children with Gricelli's syndrome is TSCA.