A Cause of Refractory Seizures: Fumarase Deficiency

Fumarase is an enzyme involved in the Krebs cycle. Fumarase deficiency (FD) is an autosomal recessive disorder that is associated with neurocognitive dysfunctions. In the absence of fumarase, fumarate is accumulated and excreted in the urine. FD has been reported with polyhydramnios, intrauterine growth retardation, prematurity, hypotonia, seizure, facial anomalies, malnutrition, relative macrocephaly, and developmental retardation. Cranial imaging findings are enlargement of the ventricles, polymicrogyria, and thinning of the corpus callosum. Electroencephalogram findings are generally compatible with hypsarrhythmia. Treatment is generally supportive. Although protein-restricted diets have been tried, their benefits have not been proven. This report aimed to present a case with hypotonia, and refractory seizures were diagnosed at a very early age, and a summary of the cases is found in the literature.