Mondo Description Fatal infantile lactic acidosis with methylmalonic aciduria is a rare neurometabolic disease characterized by infantile onset of severe encephalomyopathy, lactic acidosis and elevated methylmalonic acid urinary excretion. Clinically it manifests with severe psychomotor delay, hypotonia, failure to thrive, feeding difficulties and dystonia. Epilepsy and multiple congenital anomalies may be associated.

Uniprot Description A severe disorder due to mitochondrial dysfunction. It is characterized by infantile onset of hypotonia, lactic acidosis, severe psychomotor retardation, progressive neurologic deterioration, and excretion of methylmalonic acid.