Griscelli syndrome is a rare autosomal recessive disorder. It is characterized by stain dilution and patchy immune deficiency leading to enlarged susceptibility to sure infections and a tendency to expand a life-threatening hemophagocytic syndrome known as the accelerated phase. The connected immunodeficiency frequently involves harmed natural killer cell activity, absent delayed-type hypersensitivity, and a poor cell proliferation reply to antigenic challenge. GS is a rare disease in all populations. GS usually manifests in persons aged 4 months to 4 years. GS is not a sex-linked condition; thus, males and females are affected equally.
Griscelli syndrome is now classified into 3 types based on the inherited and molecular features. Main neurological presentation without the accelerate stage is rare in type 2. Mutation analyses in family members bare the presence of a missense mutation in Rab27a gene. GS is caused by mutations in 1 of 3 genes. Two of these genes are sited at band 15q21: RAB27A and MYO5A. These 2 genetic defects result in both alike and different physical and pathologic findings. A third type of GS (GS3), whose expression is restricted to the characteristic hypopigmentation of GS.
Griscelli syndrome results from mutation in the gene that encodes melanophilin MLPH, the ortholog of the gene transformed in leaden mice.8 it has also been exposed that an identical phenotype can effect from the deletion of the MYO5A F-exon. Children with GS caused by a defect in the RAB27A gene increase an uncontrolled T-lymphocyte and macrophage activation syndrome known as hemophagocytic syndrome (HS) or hemophagocytic lymphohistiocytosis (HLH). For patients with defects in RAB27A, antibiotics and antiviral agents are used with mixed effects. Bone marrow transplantation is the most helpful treatment of this condition.
Bone marrow transplantation is the only possible treat for GS. Even a low number of donor cells in the patient's bone marrow can be enough to manage symptoms of GS in cases caused by mutations in RAB27A. Chemotherapy (VP16) or, more just, antithymocyte globulins (ATG) and cyclosporin a have achieved remissions, and the utilize of intrathecal methotrexate injections transiently assist treat the neurocerebral involvement. However, chemotherapy is sometimes useless for the treatment of the primary disease and frequently fails to manage relapses.
