Mevalonic aciduria (MVA) is a rare genetic condition that causes recurring episodes of elevated body temperature (fevers) from infancy through childhood that tend to become less frequent in adulthood. The fevers usually last 3 to 6 days, and may happen as often as 25 times per year. During the fevers, affected individuals may suffer from abdominal pain, joint pain, headache, skin rashes, and diarrhea and may also have an enlarged liver and spleen (hepatosplenomegaly). Children with the disorder typically do not reach developmental milestones at the expected time (developmental delays), have trouble gaining weight, have trouble with movements (ataxia), and often have abnormal physical features, including a long face with a small head (microcephaly). Adolescents often suffer from eye-inflammation that may cause vision loss that gets worse with time. Adults are often short and develop muscle weakness (myopathy).
MVA is caused by changes (mutations) in the MVK gene, which provides instructions for the body to make an enzyme called mevalonate kinase. This enzyme is involved with making cholesterol, a substance that is important for many functions in the body. Mutations in the MVK gene cause the body to decrease production of the enzyme (mevalonate kinase enzyme deficiency) and, in turn, not enough cholesterol. MVA is inherited in an autosomal recessive way, meaning a child needs a mutation in both of their MVK gene copies to have the condition. MVA is the severe form of mevalonate kinase enzyme deficiency. Another condition, known as hyperimmunoglobulinemia D syndrome (HIDS) is the mild form of mevalonate kinase enzyme deficiency and is discussed in a separate entry.
There is currently not a cure for MVA. If your child has been diagnosed with MVA, talk with their doctor about ways to manage the symptoms. Support groups can provide additional information and connect you with others affected by this condition.