Kapur et al. (Am J Surg Path 2011 May;35(5):714-22) described the gastrointestinal neuromuscular pathology of several patients with POLG related mitochondrial disease and gastrointestinal dysmotility. The findings include unusual eosinophilic cytoplasmic granules corresponding to abnormal mitochondrial in parts of the enteric ganglia. Similar pathological findings were previously reported in another mitochondrial disease associated with gastrointestinal dysmotility, MNGIE.
In our patient cohort with propionic acidemia and methylmalonic acidemia, bowel dysmotility can be a debilitating complication. Considering all of the “mitochondrial features” seen as late complications of these disorders including acute optic atrophy and hearing loss, could bowel dysmotility possibly be another manifestation of secondary mitochondrial dysfunction?
Hilary Vernon MD PhD