Tyrosinemia Type 1 and Reversible Neurogenic Crisis After One Month Interruption of Nitisinone

Hereditary tyrosinemia type 1 is an autosomal recessive disorder due to deficiency of the enzyme fumarylacetoacetate hydrolase. Liver is the primary organ that is affected and comorbidities involving the renal and neurologic systems and hepatocellular carcinoma can be seen as a long term complication. An effective medical treatment with 2-[2-nitro-4-trifluoromethylbenzoyl]-1,3-cyclohexanedione (NTBC) has been available since 1992. Neurogenic crises do not occur in patients with tyrosinaemia type I treated with NTBC. Here in we report a seven years-old boy with severe neurological crisis after interruption of NTBC treatment including anorexia, vomiting, weakness, hyponatremia, paresthesia and paralysis of the extremities, seizure and arterial hypertension. Re-introduction of NTBC, the patient slowly regained normal neurological functions and normal blood pressure and recovered completely.