Definition:

Mevalonate kinase deficiency is an autosomal recessive disorder, which is identified as the cause of two inherited human autoinflammatory disorders: mevalonic aciduria (MVA) and hyperimmunoglobulinemia D syndrome (HIDS). Mevalonate kinase is located at the beginning of the cholesterol biosynthesis pathway compromising the biosynthesis of nonsterol isoprenes in addition to cholesterol. Patients of MVA show the symptoms, including dysmorphic features, cataracts, and neurologic symptoms. The majority of patients with HIDS experience only recurrent febrile crises, without any neurologic abnormalities or dysmorphic features. Mevalonic kinase activity in HIDS patients is generally in the range of 5-15% of normal as compared to 0-4% in MVA.