TYMP and mitochondrial neurogastrointestinal encephalomyopathy: Both these disorders can be virtually, clinically indistinguishable from MNGIE due to mutations in TYMP. However, brain MRI is usually different and shows no leukoencephalopathy in MTDPS-4B and increased the T2-weighted signal in the basal ganglia and patchy T2-weighted signals in the periventricular and subcortical white matter in MTDPS-8B [29,30,31].