Table 2.

Clinical Features of Mitochondrial Disease

Organ system	Clinical feature
Brain	Encephalopathy, microcephaly, ataxia, seizures, dementia, stroke, Parkinsonism, developmental delay and regression, intellectual impairment, psychiatric disorder, autism, cerebellar hypotonia, dystonia
Peripheral Nerve	Sensory and axonal neuropathy, dysautonomia, aberrant temperature regulation, orthostatic hypotension, abnormal sweating
Special Senses	Sensorineural hearing loss, optic atrophy, retinitis pigmentosa, cataract, aminoglycoside hearing loss
Muscle	Ophthalmoplegia, eyelid ptosis, myopathy, muscle cramping, exercise intolerance, hypotonia
Respiratory	Respiratory failure
Cardiac	Cardiac conduction defect, cardiomyopathy (dilated, restrictive, hypertrophic)
Renal	Proximal renal tubular dysfunction (Falconi syndrome), nephrotic syndrome, Barrter syndrome, tubulointerstitial disease
Endocrine	Diabetes mellitus, hypogonadism, hypoparathyroidism, infertility, short stature (not growth hormone related), growth hormone deficiency, adrenal insufficiency, exocrine pancreatitis
Gastrointestinal	Dysphagia, cyclic vomiting, pseudo-obstruction, gastrointestinal dysmotility
Hepatic	Hepatopathy, nonalcoholic steatohepatitis
Hematological	Siderblastic and macrocytic anemia, pancytopenia, erythrocyte failure
Dermatological	Lipomatosis
Skeletal	Kyphosclerosis, bone marrow failure