Abstract

Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is a rare autosomal recessive condition. Deficiency of thymidine phosphorylase disrupts the nucleoside pool, with progressive secondary mitochondrial DNA damage. MNGIE is clinically diagnosable because of a distinctive tetrad of gastrointestinal dysmotility, progressive external ophthalmoplegia, demyelinating neuropathy and asymptomatic leucoencephalopathy. The diagnosis may be confirmed genetically or biochemically. Misdiagnosis is frequent, but early and accurate recognition allows the possibility of novel transplant therapies capable of rectifying the biochemical defects. Its management remains difficult in the face of progressive disability and the risks of treatment.