* MEPOP
* Mitochondrial myopathy with sensorimotor polyneuropathy, ophthalmoplegia, and pseudo-obstruction
* Mitochondrial neurogastrointestinal encephalopathy syndrome
* MNGIE syndrome
* Myoneurogastrointestinal encephalopathy syndrome
* Oculogastrointestinal muscular dystrophy
* OGIMD
* POLIP
* Polyneuropathy, ophthalmoplegia, leukoencephalopathy, and intestinal pseudo-obstruction
* Thymidine phosphorylase deficiency

These are the major symptoms:

gastrointestinal dysmotility
feelings of fullness (satiety) after eating only a small amount
trouble swallowing (dysphagia)
nausea and vomiting after eating
episodes of abdominal pain
diarrhea
intestinal blockage
weight loss and reduced muscle mass (cachexia).
tingling, numbness, and weakness in their limbs (peripheral neuropathy), particularly in the hands and feet
droopy eyelids (ptosis)
weakness of the muscles that control eye movement (ophthalmoplegia)
hearing loss
deterioration of a type of brain tissue known as white matter can be seen with magnetic resonance imaging (MRI)

Symptoms above were summarized from this site: http://ghr.nlm.nih.gov/condition=mitochondrialneurogastrointestinalencephalopathydisease