The complete phenotype of MNGIE has not been linked to any gene other than TYMP.<h4>Methods</h4>We describe two identical twins who exhibited delayed psychomotor development, infantile bilateral cataract, congenital demyelinating polyneuropathy, and severe progressive gastrointestinal dysmotility with recurrent pseudo-obstruction episodes, along with diffuse supratentorial leukoencephalopathy that mainly overlaps with classic TYMP-related MNGIE. The gene discussed is TYMP; the disease is mitochondrial neurogastrointestinal encephalomyopathy.