Table 2.

Select Features of Fumarate Hydratase Deficiency

Feature% of Persons
Antenatal manifestations12/51 (23%)Oligohydramnios, polyhydramnios, IUGR, maternal intrahepatic cholestasis,& preeclampsia
Prematurity15/51 (30%)
DD44/51 (86%) 1Severe
Mild-moderate ID4/51 (8%)
Hypotonia35/51 (68%)
Seizures22/51 (43%)
Cortical visual impairment13/51 (25%)
Dysmorphic facial features20/51 (39%)Frontal bossing, depressed nasal bridge, anteverted nares
Microcephaly17/51 (33%)
Macrocephaly10/51 (20%)
Abnormal brain imaging47/51 (92%)Incl MRI, CT, & antenatal ultrasound findings; most notably: cerebral atrophy, white matter volume loss, polymicrogyria
Acute metabolic perturbations4/51 (8%)Metabolic acidosis, lactic acidosis, hypoglycemia, hyperammonemia
Hematologic abnormalities11/51 (22%)Neonatal polycythemia (9 persons); neutropenia (2 persons)
Dystonic posturing4/51 (8%)
Excessive irritability3/51 (6%)
Hepatic involvement5/51 (10%)Cirrhosis, acute hepatic neonatal hepatic failure, biliary atresia

DD = developmental delay; ID = intellectual disability; IUGR = intrauterine growth retardation


Note: Some infants died in the neonatal period.

From: Fumarate Hydratase Deficiency

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