How common is myoclonic epilepsy with ragged red fibers?

How common is myoclonic epilepsy with ragged red fibers?

General Discussion. MERRF (myoclonus epilepsy with ragged-red fibers) syndrome is an extremely rare disorder that appears in childhood, adolescence or adulthood after normal development early in life. MERRF syndrome affects the nervous system, skeletal muscles and other body systems.

What do ragged red fibers indicate?

Myoclonic epilepsy with ragged red fibers (MERRF) is a multisystem mitochondrial syndrome characterized by progressive myoclonus and seizures. Other features associated with MERRF include cerebellar ataxia, myopathy, cardiac arrhythmia, sensorineural hearing loss, optic atrophy, and dementia.

What causes myoclonic epilepsy with ragged red fibers?

Causes. Mutations in the MT-TK gene are the most common cause of MERRF, occurring in more than 80 percent of all cases. Less frequently, mutations in the MT-TL1, MT-TH, and MT-TS1 genes have been reported to cause the signs and symptoms of MERRF.

Is MERRF curable?

Treatment: 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.

How is MERRF diagnosed?

The diagnosis is based on clinical features and a muscle biopsy finding of ragged red fibers (RRF). In over 80% of cases, MERRF is caused by genetic changes in the mitochondrial gene called MT-TK.

What is myoclonic epilepsy?

Myoclonic seizures are characterized by brief, jerking spasms of a muscle or muscle group. They often occur with atonic seizures, which cause sudden muscle limpness.

How common is MERRF?

It is extremely rare, and has varying degrees of expressivity owing to heteroplasmy. MERRF syndrome affects different parts of the body, particularly the muscles and nervous system.

What does MERRF stand for?

Myoclonic epilepsy with ragged red fibers (MERRF) is a multisystem disorder characterized by myoclonus, which is often the first symptom, followed by generalized epilepsy, ataxia, weakness, and dementia. Symptoms usually first appear in childhood or adolescence after normal early development.

What is the life expectancy for someone with Leigh syndrome?

Life expectancy for children diagnosed with Leigh syndrome usually exceeds no more than two or three years.

How long do people with Leigh syndrome live?

Leigh syndrome is a rare inherited genetic disorder that affects the central nervous system. The prognosis of Leigh disorder is very poor, and patients with it mostly live up to six to seven years, but some may live until mid-teenage.

Is myoclonic epilepsy fatal?

Myoclonic seizures are a symptom found in a number of progressive seizure disorders. They are typically rare. Some, like EPM1, cause severe symptoms in childhood but overall life expectancy is normal. Others, such as Lafora disease, will prove fatal within 10 years.

How long does someone with mitochondrial disease live?

A small study in children with mitochondrial disease examined the patient records of 221 children with mitochondrial disease. Of these, 14% died three to nine years after diagnosis. Five patients lived less than three years, and three patients lived longer than nine years.

What are the symptoms of Leigh syndrome?

Progressive neurological deterioration associated with Leigh syndrome is marked by a variety of symptoms including generalized weakness, lack of muscle tone (hypotonia), clumsiness, tremors, muscle spasms (spasticity) that result in slow, stiff movements of the legs, and/or the absence of tendon reflexes.

Are myoclonic seizures life threatening?

Progressive myoclonus epilepsy (PME) is a group of disorders characterized by myoclonic seizures and other neurologic symptoms such as trouble walking or speaking. These rare disorders often get worse over time and sometimes are fatal.