Corticosterone methyloxidase deficiency is a disorder characterized by the kidneys’ inability to effectively absorb salt.
Corticosterone methyloxidase deficiency leads to elevated sodium and reduced potassium levels in the urine, resulting in high blood potassium and low blood sodium levels, causing metabolic acidosis. Symptoms of this condition include nausea, drowsiness, muscle weakness, dehydration, and low blood pressure, typically manifesting within the first few weeks of life. Infants with corticosterone methyloxidase deficiency often experience developmental delays and fail to achieve expected growth milestones. While severe cases may involve seizures, this condition is generally not life-threatening, and symptoms tend to improve with age. There is no cure for corticosterone methyloxidase deficiency, but it can be treated with sodium supplements as well as fludrocortisone, an enzyme replacement therapy.
Corticosterone methyloxidase deficiency is caused by pathogenic (disease-causing) variants in the CYP11B2 gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background. For example, individuals of Sephardic Jewish descent have a 1 in 30 chance to be a carrier.
Other names for this condition are 18-hydroxylase deficiency, aldosterone deficiency, aldosterone synthase deficiency, CMO deficiency, congenital hypoaldosteronism, corticosterone 18-monooxygenase deficiency, corticosterone methyl oxidase deficiency, familial hyperreninemic hypoaldosteronism, steroid 18-oxidase deficiency, and Visser-Cost syndrome.