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Elejalde syndrome
Elejalde syndrome
Elejalde syndrome (also known as neuroectodermal melanolysosomal syndrome) is an autosomal recessive disease presenting in infancy. It probably represents a variant of Griscelli syndrome type 1 and is characterized by skin hypopigmentation, silvery hair, bronze skin color after sun exposure and severe neurological impairment with seizures, severe hypotonia, and mental retardation.1โ4 It differs from Griscelli syndrome in that patients have no immunological abnormalities.
type 1 has been documented and in an affected family a p.Gly610Asp mutation in the KIT gene was found; however, this relationship has been doubted, as the reported patients had no neurofibromas and the current consensus is that they are not related.6โ11 Piebaldism has been described in association with Hirschsprung disease and with dyserythropoietic anemia type II.12โ14
Pathogenesis and histologic features Point mutations and deletions in the kit proto-oncogene have been demonstrated in most patients with piebaldism.15โ23 These different point mutations and deletions are responsible for the range of phenotypes seen in affected patients. The KIT gene encodes a cell-surface transmembrane receptor โ tyrosine kinase โ for the stem/mast cell growth factor. The gene has been mapped to chromosome 4q11-q12. The different severity of presentation is
Histology of involved hair and skin shows features similar to those seen in Griscelli syndrome (see above).