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Characteristic findings of mitochondrial disorders
  • Muscle weakness
  • Vision or hearing problems
  • Liver or kidney disorder
  • Diabetes
  • Gastrointestinal problems
  • Brain problems such as seizures
  • Fatigue which may have sudden onset
    • Individuals need to have a place to rest and recharge
    • Individuals will have good and bad days
  • Body’s inability to properly regulate temperature and stay hydrated
    • Monitor for temperature extremes 
Specific Mitochondrial Syndromes
  • Leber hereditary optic neuropathy is a disorder that affects the eye.
  • Mitochondrial hearing loss and deafness
  • Kearns-Sayre syndrome (KSS) is a condition that affects many parts of the body, especially the eyes.
  • Chronic progressive external ophthalmoplegia (CPEO) is a disorder characterized by slowly progressive paralysis of the muscles around the eyes.
  • MELAS (Mitochondrial encephalopathy with lactic acidosis and stroke like episodes) primarily affects the brain, nervous system and muscles.
  • MERRF (Myolonic epilepsy with ragged red fibers) affects the nervous system and skeletal muscle as well as other body systems.
  • NARP: Neurogenic weakness with ataxia
  • Leigh syndrome is characterized by progressive loss of mental and movement abilities (psychomotor regression) and typically results in death within a couple of years.
Non-Specific Mitochondrial Disorders
  • Overlapping features of the above conditions can occur.
  • Individuals with multiple medical symptoms have been found to have deficiencies in the function of their mitochondria do to genetic changes.
Genetics of mitochondrial disorders
  • There are approximately 1,200 people in the United States who have a mitochondrial disorder.
  • It can be caused by changes in genes that are found on chromosomes and inherited from one or both parents.
  • It can be caused by changes in genes that are only found in the mitochondria and are passed on from the mother.
Other possible findings

Brain:

  • Developmental delay
  • Mental retardation
  • Dementia
  • Seizures
  • Neuro-psychiatric disturbances
  • Migraines
  • Atypical cerebral palsy
  • Movement disorders
  • Strokes
  • Autistic features

Nerves:

  • Weakness (maybe intermittent)
  • Absent reflexes
  • Fainting
  • Neuropathic pain (pins and needles) and burning
  • Dysautonomia (temperature instability and other dysautonomic problems)

Muscles:

  • Weakness
  • Muscle pain and spasms
  • Low muscle tone and loss of muscle coordination
  • Exercise intolerance
  • May use a wheelchair

Developmental delays:

  • Learning delays
  • Autism or autism-like features
  • Gastrointestinal problems:
  • Pseudo obstruction (the impairment of the intestines in passing food through the intestines.)
  • Irritable bowel syndrome
  • Cramping
  • Diarrhea/constipation
  • Dysmotility (slowing down of bowels)
  • Unexplained vomiting
  • GI reflux

Kidneys:

  • Kidney disorder

Heart:

  • Cardiac conduction defects
  • Cardiomyopathy

Liver:

  • Hypoglycemia (low blood sugar)
  • Liver failure

Eyes and ears:

  • Visual loss/blindness
  • Ptosis (drooping of the upper eyelid)
  • Optic atrophy (deterioration of the optic nerve)
  • Hearing loss/deafness
  • Strabismus
  • Retinitis pigmentosis  (breakdown and loss of retinal cells)
  • Sensitivity to bright lights

Endocrine:

  • Diabetes and exocrine pancreatic failure
  • Inability to make digestive enzymes
  • Parathyroid failure (low calcium)
  • Hypothyroidism
  • Short stature

Systemic:

  • Failure to gain weight
  • Fatigue
  • Respiratory problems

Increased risk of infection:

  • It may take longer to recover from cold or other illnesses

Thyroid or adrenal, autonomic dysfunction