A rare cause of opistotonus; fumaric aciduria: The first case presentation in Turkey.

Fumaric aciduria is a rare autosomal recessive metabolic disease which is characterized with excessive fumaric acid exretion in urine. In the prenatal period, polyhydramniosis, intrauterine growth retardation, enlarged brain ventricles and brain anomalies are observed. Growth and development failure, hypotonia, seizures and brain atrophy are the common characteristics of patients with fumarase deficiency. On cranial imaging, the most common findings include polymicrogyria and ventriculomegaly. In our country where consanguineous marriages are common, the incidences of autosomal recessive diseases are expected to be high. In a patient who was born from a consanguineous marriage and referred to our hospital at the age of 45 days because of hyperamonemia and opistotonus, a diagnosis of fumaric aciduria was made with organic acid analysis performed considering metabolic diseases and this diagnosis was supported with radiological investigations. We thought this case was worth presenting, since there was no case of fumaric aciduria reported before in our country.