Types of Mitochondrial Disease

Mitochondrial Disease Capsules:

Long name: Progressive Infantile Poliodystrophy.

Symptoms: seizures, dementia, spasticity, blindness, liver dysfunction, and cerebral degeneration.

Source: Dr. Rolf Luft; The development of mitochondrial medicine. [Review] ; Proceedings of the National Academy of Sciences of the United States of America ; 1994 ; 91(19) ; 8731-8

Links: https://rarediseases.info.nih.gov/diseases/5783/alpers-syndrome

Barth Syndrome / LIC (Lethal Infantile Cardiomyopathy)

Symptoms: skeletal myopathy, cardiomyopathy, short stature, and neutropenia.

Cause: X-linked recessive.

Source: Dr. J. Christodoulou; Barth syndrome: clinical observations and genetic linkage studies; American Journal of Medical Genetics; 1994 ; 50(3) ; 255-64

Links: Barth Syndrome Family Network – http://www.barthsyndrome.org/

Beta-oxidation Defects


Treatment: High carbohydrate-low fat diet, administration of medium-chain triglyceride oil, and diet supplementation with carnitine and/or riboflavin. Avoidance of fasting.

Links: The FOD (Fatty acid Oxidation Disorder) Network On-line Newsletter – http://www.fodsupport.org/

NOTE: Information about treatments is very general and for informational purposes only. No treatment should be implemented without first speaking to your physician.

Carnitine-Acyl-Carnitine Deficiency

Symptoms: Seizures, apnea, bradycardia, vomiting, lethargy, coma, enlarged liver, limb weakness, myoglobin in the urine, Reye-like symptoms triggered by fasting.

Cause: Autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/1123/carnitine-acylcarnitine-translocase-deficiency
The FOD (Fatty acid Oxidation Disorder) Network On-line Newsletter – http://www.fodsupport.org/

Carnitine Deficiency

Symptoms: Seizures, apnea, bradycardia, vomiting, lethargy, coma, enlarged liver, limb weakness, myoglobin in the urine, Reye-like symptoms triggered by fasting.

Cause: Autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/5104/primary-carnitine-deficiency

Creatine Deficiency Syndromes

Additional names: Cerebral Creatine Deficiency Syndromes (CCDS) Includes: Guanidinoaceteate Methyltransferase Deficiency (GAMT Deficiency), L-Arginine:Glycine Amidinotransferase Deficiency (AGAT Deficiency), and SLC6A8-Related Creatine Transporter Deficiency (SLC6A8 Deficiency).

Symptoms: general: mental retardation, seizures, speech delay. Additional possible symptoms: GAMT – behavioral disorder – including autistic behaviors; movement disorders SLC6A8 – growth retardation; (males) mild to severe mental retardation; (females) learning and behavior problems

Cause: GAMT & AGAT – autosomal recessive; SLC6A8 – X-linked.

Links: https://rarediseases.info.nih.gov/diseases/2578/guanidinoacetate-methyltransferase-deficiency

Co-Enzyme Q10 Deficiency

Symptoms: Encephalomyopathy, mental retardation, exercise intolerance, ragged-red fibers, and recurrent myoglobin in the urine.

Cause: Probably autosomal recessive.

Treatment: Administration of Co-enzyme Q10

Links: https://rarediseases.info.nih.gov/diseases/10423/coenzyme-q10-deficiency

Complex I Deficiency

Long Name: NADH dehydrogenase (NADH-CoQ reductase) deficiency.

Inside the mitochondrion is a group of proteins that carry electrons along four chain reactions (Complexes I-IV), resulting in energy production. This chain is known as the Electron Transport Chain. A fifth group (Complex V) churns out the ATP. Together, the electron transport chain and the ATP synthase form the respiratory chain and the whole process is known as oxidative phosphorylation or OXPHOS.

Complex I, the first step in this chain, is the most common site for mitochondrial abnormalities, representing as much as one third of the respiratory chain deficiencies. Often presenting at birth or in early childhood, Complex I deficiency is usually a progressive neuro-degenerative disorder and is responsible for a variety of clinical symptoms, particularly in organs and tissues that require high energy levels, such as brain, heart, liver, and skeletal muscles. A number of specific mitochondrial disorders have been associated with Complex I deficiency including: Leber’s hereditary optic neuropathy (LHON), MELAS, MERRF, and Leigh Syndrome (LS).

There are three major forms of Complex I deficiency:

1. Myopathy (muscle disease) – starting in childhood or adulthood, and characterized by weakness or exercise intolerance.

2. Mitochondrial encephalomyopathy (brain and muscle disease) – beginning in childhood or adulthood and involving variable symptom combinations which may include: eye muscle paralysis, pigmentary retinopathy (retinal color changes with loss of vision), hearing loss, sensory neuropathy (nerve damage involving the sense organs), seizures, dementia, ataxia (abnormal muscle coordination), and involuntary movements. This form of Complex I deficiency may cause Leigh Syndrome and MELAS.

3. Fatal infantile multisystem disorder – characterized by poor muscle tone, developmental delay, heart disease, lactic acidosis, and respiratory failure.

Most cases of Complex I deficiency result from autosomal recessive inheritance (combination of defective nuclear genes from both the mother and the father). Less frequently, the disorder is maternally inherited or sporadic and the genetic defect is in the mitochondrial DNA.

Treatment: As with all mitochondrial diseases, there is no cure for Complex I deficiency. A variety of treatments, which may or may not be effective, can include such metabolic therapies as: riboflavin, thiamine, biotin, co-enzyme Q10, carnitine, and the ketogenic diet. Therapies for the infantile multisystem form have been unsuccessful.

The clinical course and prognosis for Complex I patients is highly variable and may depend on the specific genetic defect, age of onset, organs involved, and other factors.

Cause: Autosomal.

Click Here to download this mito profile (PDF)
Links: https://rarediseases.info.nih.gov/diseases/3908/mitochondrial-complex-i-deficiency

Complex II Deficiency

Long Name: Succinate dehydrogenase deficiency.

Symptoms: Encephalomyopathy and various manifestations, including failure to thrive, developmental delay, hyoptonia, lethargy, respiratory failure, ataxia, myoclonus. Lactic acidosis common. May cause Leigh Syndrome.

Cause: Probably autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/5053/mitochondrial-complex-ii-deficiency

Complex III Deficiency

Long Name: Ubiquinone-cytochrome c oxidoreductase deficiency.

Symptoms: Four major forms:

1. Fatal infantile encephalomyopathy, congenital lactic acidosis, hypotonia, dystrophic posturing, seizures, and coma. Ragged-red fibers common.
2. Encephalomyopathies of later onset (childhood to adult life): various combinations of weakness, short stature, ataxia, dementia, hearing loss, sensory neuropathy, pigmentary retinopathy, and pyramidal signs. Ragged-red fibers common. Possible lactic acidosis.
3. Myopathy, with exercise intolerance evolving into fixed weakness. Ragged-red fibers common. Possible lactic acidosis.
4. Infantile histiocytoid cardiomyopathy.

Cause: Probably autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/8295/mitochondrial-complex-iii-deficiency

Complex IV Deficiency / COX Deficiency

Long Name: Cytochrome c oxidase deficiency is caused by a defect in Complex IV of the respiratory chain.

Symptoms: Two major forms:

1. Encephalomyopathy: Typically normal for the first 6 to 12 months of life and then show developmental regression, ataxia, lactic acidosis, optic atrophy, ophthalmoplegia, nystagmus, dystonia, pyramidal signs, and respiratory problems. Frequent seizures. May cause Leigh Syndrome
2. Myopathy: Two main variants:
1. Fatal infantile myopathy: may begin soon after birth and accompanied by hypotonia, weakness, lactic acidosis, ragged-red fibers, respiratory failure, and kidney problems.
2. Benign infantile myopathy: may begin soon after birth and accompanied by hypotonia, weakness, lactic acidosis, ragged-red fibers, respiratory problems, but (if the child survives) followed by spontaneous improvement.

Cause: Probably autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/48/cytochrome-c-oxidase-deficiency

Complex V Deficiency

Long Name: ATP synthase deficiency.

Symptoms: Slow, progressive myopathy.

Links: https://rarediseases.info.nih.gov/diseases/1459/mitochondrial-complex-v-deficiency


Long Name: Chronic Progressive External Ophthalmoplegia Syndrome.

Symptoms: Similar to those of KSS plus: visual myopathy, retinitis pigmentosa, dysfunction of the central nervous system.

Cause: Single mitochondrial DNA deletions. Mitochondrial DNA point mutations: A3243G (most common)

Source: Dr. Rolf Luft; The development of mitochondrial medicine. [Review] ;Proceedings of the National Academy of Sciences of the United States of America ; 1994 ; 91(19) ; 8731-8

Links: https://rarediseases.info.nih.gov/diseases/4503/chronic-progressive-external-ophthalmoplegia

CPT I Deficiency

Symptoms: Enlarged liver and recurrent Reye-like episodes triggered by fasting or illnesses.

Cause: Autosomal recessive.

Treatment: Medium-chain triglycerides.

Links: https://rarediseases.info.nih.gov/diseases/1120/carnitine-palmitoyl-transferase-1-deficiency

CPT II Deficiency

Symptoms – Myopathic: Exercise intolerance, fasting intolerance, muscle pain, muscle stiffness, and myoglobin in the urine.

Symptoms – Infantile: Reye-like syndrome, enlarged liver, hypoglycemia, enlarged heart, and cardiac arrhythmia.

Cause: Autosomal recessive.

Treatment – Non-Infantile: High carbohydrate, low-fat diet.

Links: https://rarediseases.info.nih.gov/diseases/1121/carnitine-palmitoyltransferase-2-deficiency


Long name: Kearns-Sayre Syndrome.

KSS is a slowly progressive multi-system mitochondrial disease that often begins with drooping of the eyelids (ptosis). Other eye muscles eventually become involved, resulting in paralysis of eye movement. Degeneration of the retina usually causes difficulty seeing in dimly lit environments.

KSS is characterized by three main features:

• typical onset before age 20 although may occur in infancy or adulthood
• paralysis of specific eye muscles (called chronic progressive external ophthalmoplegia – CPEO)
• degeneration of the retina causing abnormal accumulation of pigmented (colored)material (pigmentary retinopathy).

In addition, one or more of the following conditions is present:

• block of electrical signals in the heart (cardiac conduction defects)
• elevated cerebrospinal fluid protein
• incoordination of movements (ataxia).

Patients with KSS may also have such problems as deafness, dementia, kidney dysfunction, and muscle weakness. Endocrine abnormalities including growth retardation, short stature, or diabetes may also be evident.

KSS is a rare disorder. It is usually caused by a single large deletion (loss) of genetic material within the DNA of the mitochondria (mtDNA), rather than in the DNA of the cell nucleus. These deletions, of which there are over 150 species, typically arise spontaneously. Less frequently, the mutation is transmitted by the mother.

As with all mitochondrial diseases, there is no cure for KSS. Treatments are based on the types of symptoms and organs involved, and may include: Coenzyme Q10, insulin for diabetes, cardiac drugs, and a cardiac pacemaker which may be life-saving. Surgical intervention for drooping eyelids may be considered but should be undertaken by specialists in ophthalmic surgical centers.

KSS is slowly progressive and the prognosis varies depending on severity. Death is common in the third or fourth decade and may be due to organ system failures.

Cause: Most cases are due to large mitochondria DNA deletions.

Links: https://rarediseases.info.nih.gov/diseases/6817/kearns-sayre-syndrome

Lactic Acidosis

Cause: The accumulation of lactic acid due to its production exceeding its use. Chronic lactic acidosis is a common symptom of mitochondrial disease.

Links: https://rarediseases.info.nih.gov/diseases/3163/lactic-acidosis-congenital-infantile

LBSL – Leukodystrophy

Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) is a result of a DARS2 gene mutation and is characterized by slowly progressive cerebellar ataxia and spasticity with dorsal column dysfunction (decreased position and vibration sense). The neurologic dysfunction involves the legs more than the arms. The tendon reflexes are retained. Deterioration of motor skills usually starts in childhood or adolescence, but occasionally not until adulthood. Dysarthria develops over time. Occasional findings include epilepsy; learning problems; cognitive decline; and reduced consciousness, neurologic deterioration, and fever following minor head trauma. Many affected individuals become wheelchair dependent in their teens or twenties. LBSL is inherited in an autosomal recessive manner. At conception, each sib of an affected individual has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. Carrier testing for at-risk family members and prenatal testing for pregnancies at increased risk are possible if the disease-causing mutations have been identified in the family.

Links: https://rarediseases.info.nih.gov/diseases/12652/leukoencephalopathy-with-brain-stem-and-spinal-cord-involvement-and-lactate-elevation


Long Name: Long-Chain Acyl-CoA Dehydrongenase Deficiency.

Symptoms: Usually causes a fatal syndrome, in infants, typified by failure to thrive, enlarged liver, enlarged heart, metabolic encephalopathy, and hypotonia.

Cause: Autosomal recessive.

Treatment: See Beta-oxidation Defects.

Links: https://rarediseases.info.nih.gov/diseases/9700/lcad-deficiency


Symptoms: Encephalopathy, liver dysfunction, cardiomyopathy, and myopathy. Also pigmentary retinopathy and peripheral neuropathy.

Cause: Autosomal recessive.

Treatment: See Beta-oxidation Defects.

Links: https://rarediseases.info.nih.gov/diseases/6867/lchad-deficiency

Leigh Disease or Syndrome

Long Name: Subacute Necrotizing Encephalomyelopathy.

Symptoms: Seizures, hypotonia, fatigue, nystagmus, poor reflexes, eating & swallowing difficulties, breathing problems, poor motor function, ataxia.

Cause: Pyruvate Dehydrogenase Deficiency, Complex I Deficiency, Complex II Deficiency, Complex IV/COX Deficiency, NARP.

Leigh’s Disease is a progressive neurometabolic disorder with a general onset in infancy or childhood, often after a viral infection, but can also occur in teens and adults. It is characterized on MRI by visible necrotizing (dead or dying tissue) lesions on the brain, particularly in the midbrain and brainstem.

The child often appears normal at birth but typically begins displaying symptoms within a few months to two years of age, although the timing may be much earlier or later. Initial symptoms can include the loss of basic skills such as sucking, head control, walking and talking. These may be accompanied by other problems such as irritability, loss of appetite, vomiting and seizures. There may be periods of sharp decline or temporary restoration of some functions. Eventually, the child may also have heart, kidney, vision, and breathing complications.

There is more than one defect that causes Leigh’s Disease. According to Dr. David Thorburn, at least 26 defects have been identified. These include a pyruvate dehydrogenase (PDHC) deficiency, and respiratory chain enzyme defects – Complexes I, II, IV, and V. Depending on the defect, the mode of inheritance may be X-linked dominant (defect on the X chromosome and disease usually occurs in males only), autosomal recessive (inherited from genes from both mother and father), and maternal (from mother only). There may also be spontaneous cases which are not inherited at all.

One estimate of the incidence of Leigh’s disease (Leigh Syndrome: Clinical Features and Biochemical and DNA Abnormalities by Dr. David Thorburn, PhD of Melbourne, Australia) is one in 77,000 births or one per 40,000 births for Leigh and Leigh-like disease (a milder version of the syndrome, often not proven by imaging or autopsy). However, this may be an underestimate since mitochondrial diseases tend to be under-diagnosed and misdiagnosed.

There is no cure for Leigh’s Disease. Treatments generally involve variations of vitamin and supplement therapies, often in a “cocktail” combination, and are only partially effective. Various resource sites include the possible usage of: thiamine, coenzyme Q10, riboflavin, biotin, creatine, succinate, and idebenone. Experimental drugs, such as dichloroacetate (DCA) are also being tried in some clinics. In some cases, a special diet may be ordered and must be monitored by a dietitian knowledgeable in metabolic disorders.

The prognosis for Leigh’s Disease is poor. Depending on the defect, individuals typically live anywhere from a few years to the mid-teens. Those diagnosed with Leigh-like syndrome or who did not display symptoms until adulthood tend to live longer.

Links: https://rarediseases.info.nih.gov/diseases/6877/leigh-syndrome

Luft Disease

Symptoms: Hypermetabolism, with fever, heat intolerance, profuse perspiration, polyphagia, polydipsia, ragged-red fibers, and resting tachycardia. Exercise intolerance with mild weakness.

Cause: Unknown inheritance.

MAD / Glutaric Aciduria Type II

Long Name: Multiple Acyl-CoA Dehydrogenase Deficiency.

Cause: Defects of the flavoproteins responsible for transferring electrons (ETF or ETF-dehydrogenase) therefor affecting the function of all six ETF-funneling acyl-CoA dehydrogenases.

Links: https://rarediseases.info.nih.gov/diseases/6523/glutaric-acidemia-type-ii
The FOD (Fatty acid Oxidation Disorder) Network On-line Newsletter – http://www.fodsupport.org/


Long Name: Medium-Chain Acyl-CoA Dehydrongenase Deficiency.

Symptoms: Afflicts infants or young children with episodes of encephalopathy, enlarged and fatty degeneration of the liver, and low carnitine in the blood.

Cause: Autosomal recessive.

Treatment: See Beta-oxidation Defects.

Links: https://rarediseases.info.nih.gov/diseases/540/medium-chain-acyl-coenzyme-a-dehydrogenase-deficiency


Long Name: Mitochondrial Encephalomyopathy Lactic Acidosis and Strokelike Episodes.

Symptoms: Short statue, seizures, stroke-like episodes with focused neurological deficits, recurrent headaches, cognitive regression, disease progression, ragged-red fibers.

Cause: Mitochondrial DNA point mutations: A3243G (most common).

MELAS – Mitochondrial Myopathy (muscle weakness), Encephalopathy (brain and central nervous system disease), Lactic Acidosis (buildup of a cell waste product), and Stroke-like Episodes (partial paralysis, partial vision loss, or other neurological abnormalities).
MELAS is a progressive neurodegenerative disorder with typical onset between the ages of 2 and 15, although it may occur in infancy or as late as adulthood. Initial symptoms may include stroke-like episodes, seizures, migraine headaches, and recurrent vomiting.

Usually, the patient appears normal during infancy, although short stature is common. Less common are early infancy symptoms that may include developmental delay, learning disabilities or attention-deficit disorder. Exercise intolerance, limb weakness, hearing loss, and diabetes may also precede the occurrence of the stroke-like episodes.

Stroke-like episodes, often accompanied by seizures, are the hallmark symptom of MELAS and cause partial paralysis, loss of vision, and focal neurological defects. The gradual cumulative effects of these episodes often result in variable combinations of loss of motor skills (speech, movement, and eating), impaired sensation (vision loss and loss of body sensations), and mental impairment (dementia). MELAS patients may also suffer additional symptoms including: muscle weakness, peripheral nerve dysfunction, diabetes, hearing loss, cardiac and kidney problems, and digestive abnormalities. Lactic acid usually accumulates at high levels in the blood, cerebrospinal fluid, or both.

MELAS is maternally inherited due to a defect in the DNA within mitochondria. There are at least 17 different mutations that can cause MELAS. By far the most prevalent is the A3243G mutation, which is responsible for about 80% of the cases. The incidence is unknown, although the epidemiological studies of the MELAS-3243 mtDNA mutation have estimated the prevalence to be 1-16/100,000 in the adult population.

There is no cure or specific treatment for MELAS. Although clinical trials have not proven their efficacy, general treatments may include such metabolic therapies as: CoQ10, creatine, phylloquinone, and other vitamins and supplements. Drugs such as seizure medications and insulin may be required for additional symptom management. Some patients with muscle dysfunction may benefit from moderate supervised exercise. In select cases, other therapies that may be prescribed include dichloroacetate (DCA) and menadione, though these are not routinely used due to their potential for having harmful side effects.

The prognosis for MELAS is poor. Typically, the age of death is between 10 to 35 years, although some patients may live longer. Death may come as a result of general body wasting due to progressive dementia and muscle weakness, or complications from other affected organs such as heart or kidneys.

Source: Betty Koo, et. al.; Mitochondrial encephalomyopathy, lactic acidosis, stroke-like episodes (MELAS): clinical, radiological, pathological, and genetic observations. ; Annals of Neurology ; 1993 ; 34(1) ; 25-32

Links: https://rarediseases.info.nih.gov/diseases/7009/mitochondrial-encephalomyopathy-lactic-acidosis-and-stroke-like-episodes


Long Name: Mitochondrial Enoyl CoA Reductase Protein Associated Neurodegeneration.

MEPAN is caused by 2 mutations in the gene MECR ( which encodes the protein mitochondrial trans-2-enoyl-coenzyme A-reductase), a newly described mitochondrial disease, which includes optic atrophy, childhood-onset dystonia (a movement disorder involving high tone and posturing); children may develop difficulty walking, with speech articulation and with vision loss.

MRI lesions in the basal ganglia can mimic Leigh syndrome as well as one of the NBIA disorders (neurodegneration with brain iron accumulation).

Common symptoms: movement disorder (dystonia, spasticity, chorea, ataxia) in childhood, reduced vision, difficulty with speech (dysarthria), balance issues

Links: https://rarediseases.info.nih.gov/diseases/13488/mepan-syndrome


Long Name: Myoclonic Epilepsy and Ragged-Red Fiber Disease.

Symptoms: Myoclonus, epilepsy, progressive ataxia, muscle weakness and degeneration, deafness, and dementia.

Cause: Mitochondrial DNA point mutations: A8344G, T8356C.

MERRF is a progressive multi-system syndrome usually beginning in childhood, but onset may occur in adulthood. The rate of progression varies widely. Onset and extent of symptoms can differ among affected siblings.

The classic features of MERRF include:

• Myoclonus (brief, sudden, twitching muscle spasms) – the most characteristic symptom
• Epileptic seizures
• Ataxia (impaired coordination)
• Ragged-red fibers (a characteristic microscopic abnormality observed in muscle biopsy of patients with MERRF and other mitochondrial disorders) Additional symptoms may include: hearing loss, lactic acidosis (elevated lactic acid level in the blood), short stature, exercise intolerance, dementia, cardiac defects, eye abnormalities, and speech impairment.

Although a few cases of MERRF are sporadic, most cases are maternally inherited due to a mutation within the mitochondria. The most common MERRF mutation is A8344G, which accounted for over 80% of the cases (GeneReview article). Four other mitochondrial DNA mutations have been reported to cause MERRF. While a mother will transmit her MERRF mutation to all of her offspring, some may never display symptoms.

As with all mitochondrial disorders, there is no cure for MERRF. Therapies may include coenzyme Q10, L-carnitine, and various vitamins, often in a “cocktail” combination. Management of seizures usually requires anticonvulsant drugs. Medications for control of other symptoms may also be necessary.

The prognosis for MERRF varies widely depending on age of onset, type and severity of symptoms, organs involved, and other factors.

Source: Dr. Rolf Luft; The development of mitochondrial medicine. [Review] ;Proceedings of the National Academy of Sciences of the United States of America ; 1994 ; 91(19) ; 8731-8 & DiMauro

Links: https://rarediseases.info.nih.gov/diseases/7144/myoclonic-epilepsy-with-ragged-red-fibers


Long Name: Mitochondrial Recessive Ataxia Syndrome.

Symptoms: encephalopathy, balance problems, ataxia, epilepsy, cognitive impairment, psychiatric symptoms, eye movement disorders, involuntary movements, peripheral neuropathy.

Cause: POLG mutation, Recessive inheritance: Many sporadic cases.

Mitochondrial Cytopathy

General classification for mitochondrial diseases. All diseases listed here are mitochondrial cytopathies.

See Mitochondrial Cytopathies: A Primer (PDF) for a general description of mitochondrial disease.

Mitochondrial DNA Depletion

Symptoms: Three forms:
1. Congenital myopathy: Neonatal weakness, hypotonia requiring assisted ventilation, possible renal dysfunction. Severe lactic acidosis. Prominent ragged-red fibers. Death due to respiratory failure usually occurs prior to one year of age.
2. Infantile myopathy: Following normal early development until one year old, weakness appears and worsens rapidly, causing respiratory failure and death typically within a few years.
3. Hepatopathy: Enlarged liver and intractable liver failure, myopathy. Severe lactic acidosis. Death is typical within the first year.

Cause: Probably autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/13643/mitochondrial-dna-depletion-syndrome

Includes: Encephalomyopathy, Encephalomyelopathy

Long Name: Myoneurogastointestinal Disorder and Encephalopathy.

Symptoms: Progressive external ophthalmoplegia, limb weakness, peripheral neuropathy, digestive tract disorders, leukodystrophy, lactic acidosis, ragged red fibers.

Links: https://rarediseases.info.nih.gov/diseases/9920/mitochondrial-neurogastrointestinal-encephalopathy-syndrome


Long Name: Neuropathy, Ataxia, and Retinitis Pigmentosa.

Cause: Mitochondrial DNA point mutations in genes associated with Complex V: T8993G, (also T8993C by some researchers). Leigh Syndrome may result if the percentage of mutation is high enough.

Links: https://rarediseases.info.nih.gov/diseases/262/neuropathy-ataxia-retinitis-pigmentosa-syndrome

Pearson Syndrome

Symptoms: Bone marrow and pancreas dysfunction.

Cause: Single mitochondrial DNA deletions. Inheritance is usually sporadic. Those who survive infancy usually develop Kearns-Sayre Syndrome.

Links: https://rarediseases.info.nih.gov/diseases/7343/pearson-syndrome

Pyruvate Carboxylase Deficiency

Symptoms: Lactic acidosis, hypoglycemia, severe retardation, failure to thrive.

Common symptoms: seizures and spasticity.

Cause: Autosomal recessive.

Links: https://rarediseases.info.nih.gov/diseases/7512/pyruvate-carboxylase-deficiency

Pyruvate Dehydrogenase Deficiency

Symptoms: Lactic acidosis, ataxia, pyruvic acidosis, spinal and cerebellar degeneration.

Less common: Agenesis of the corpus callosum and lesions in the basal ganglia, cerebelum, and brain stem.

Also: growth delay, hypotonia, seizures, and polyneuropathy. Sometimes found to be the cause of Leigh Syndrome.

Cause: Varies.

Links: https://rarediseases.info.nih.gov/diseases/7513/pyruvate-dehydrogenase-complex-deficiency

POLG Mutations

See: Mitochondrial News Volume 14 Issue 2
See: POLG Related Disorders – https://www.ncbi.nlm.nih.gov/pubmed/20301791


Long Name: Short-Chain Acyl-CoA Dehydrogenase Deficiency.

Symptoms: Failure to thrive, developmental delay, and hypoglycemia.

Cause: Autosomal recessive.

Treatment: See Beta-oxidation Defects.

Links: https://rarediseases.info.nih.gov/diseases/4822/short-chain-acyl-coa-dehydrogenase-deficiency

The FOD (Fatty acid Oxidation Disorder) Network On-line Newsletter – http://www.fodsupport.org/


Symptoms: Encephalopathy and possibly liver disease or cardiomyopathy.

Cause: Autosomal recessive.

Treatment: See Beta-oxidation Defects.

Links: https://rarediseases.info.nih.gov/diseases/9870/3-alpha-hydroxyacyl-coa-dehydrogenase-deficiency
The FOD (Fatty acid Oxidation Disorder) Network On-line Newsletter http://www.fodsupport.org/


Long Name: Very Long-Chain Acyl-CoA Dehydrogenase Deficiency.

Symptoms: Various manifestations, ranging from fatal infantile encephalopathy to recurrent myoglobin in the urine, similar to the myopathic form of CPT II deficiency.

Cause: Autosomal recessive.

Treatment: See Beta-oxidation Defects.

Links: https://rarediseases.info.nih.gov/diseases/5508/vlcad-deficiency
The FOD (Fatty acid Oxidation Disorder) Network On-line Newsletter – http://www.fodsupport.org/