Autosomal recessive disorder caused by mutations in the mevalonate kinase gene. Because of the mutations cholesterol biosynthesis is disrupted and mevalonic acid accumulates. It is characterized by a range of symptoms, including dysmorphic facies, psychomotor retardation, cataract, hepatosplenomegaly, cerebellar ataxia, elevated immunoglobulin d, and recurrent febrile crises with fever; LYMPHADENOPATHY; arthralgia; edema; and rash.