MELAS syndrome: symptoms, causes and treatment

This rare disease can produce epileptic seizures and cognitive and motor disturbances.

Among the diseases categorized as rare we find MELAS Syndrome, a rare condition that, in Spain which, in Spain, only affects less than 5 out of every 100,000 people over 14 years of age. This alteration of mitochondrial origin seriously affects the neurological functioning of the person and its symptoms manifest themselves until the moment of death.

Throughout this article we will describe in detail what this hereditary disease consists of, as well as its symptoms, where the origin of the condition lies and how the possible treatments are carried out.

What is MELAS Syndrome?

MELAS syndrome is a rare inherited mitochondrial disease whose main feature is the generation of a series of neurological is the generation of a series of neurological alterations.. Mitochondrial category conditions cause in the person certain neurological disorders caused by a mitochondrial genomic mutation.

Mitochondria are cytoplasmic organelles formed by eukaryotic cells, whose main mission is to generate energy by consuming oxygen. This organelle is essential for the metabolism of our cells, so any alteration in it can cause serious complications in the health and quality of life of the person.

This syndrome was first described in 1975, but it was not until 1984 that it received its current name. The term MELAS is an acronym for its most distinctive clinical properties:

• ME: mitochondrial encephalomyopathy (mitochondrial encephalomyopathy).
• LA: Lactic acidosis (lactic acidosis).
• S: Stroke-like episodes.

In its first description, the MELAS syndrome was described as a group of seizure incidents, gradual language degeneration, lactic acidosis and muscle fiber tears..

The first symptoms of this condition usually appear during childhood or adolescence, especially between the ages of 2 and 5 years. In spite of the fact that the development of the disease can vary considerably among those who suffer from it, the prognosis tends to be quite reserved in the great majority of the cases; since the patients develop serious health complications until they die.

As for the incidence of MELAS syndrome, this is a very rare condition among the population. Although specific data on its prevalence have not been established, it is known that it is one of the most common mitochondrial diseases. is one of the most common mitochondrial diseases.. On the other hand, no higher prevalence has been demonstrated in males or females, nor in any particular ethnic or racial group.

What is the clinical picture?

As we have pointed out above, MELAS syndrome is distinguished by having three main features that make up its clinical picture and differentiate it from other mitochondrial diseases.

1. Mitochondrial encephalomyopathy (ME)

Encephalomyopathies are those diseases whose origin lies in alterations in the structure and functioning of the central nervous system, which have to cause quite frequent convulsive episodes.

These episodes consist of temporally delimited events during which the person suffers exaggerated motor agitation, spasmodic and involuntary muscular activity and changes in the state of consciousness and perception. A distinction can be made between focal seizures and generalized seizures.. In focal seizures, abnormal brain electrical activity is usually restricted to a specific area of the brain, whereas in generalized seizures the discharge patterns extend to several brain areas.

The danger of these epileptic seizures lies in the risk that the different brain structures affected may be permanently impaired, leading to serious cognitive and motor consequences.

2. Lactic acidosis (LA)

Lactic acidosis present in MELAS syndrome consists of an abnormal accumulation of lactic acid in the brain. abnormal accumulation of lactic acid.. When this substance, generated mainly in red Blood cells and muscle cells, accumulates in a pathological manner, it can lead to a series of very serious health problems that can eventually result in the death of the patient.

The main signs that indicate a build-up of lactic acid include vomiting, diarrhea, nausea, gastric pain, prolonged drowsiness, alterations in consciousness, respiratory problems, hypotension, dehydration and deficits in blood and oxygen supply to muscles, tissues and organs.The patient may suffer from: vomiting, alterations in the state of consciousness, respiratory problems, hypotension, dehydration and deficits in the supply of blood and oxygen to muscles, tissues and organs.

Stroke-like (S)

Stroke-like refers to stroke-like events or cerebral strokes..

A stroke is a focal, spontaneous event in which the blood flow in a specific area of the brain is interrupted. When this occurs for more than a few seconds, brain cells begin to deteriorate and die due to lack of oxygen and nutrients.

The main consequences of these strokes are visual, language and motor impairments, as well as a gradual cognitive deterioration that can lead to dementia. to dementia..

What are the symptoms?

In MELAS syndrome, the clinical picture described above is accompanied by a symptomatology that, despite presenting in a very disparate manner among patients, usually appears in the vast majority of cases.

These symptoms include:

• Migraines and recurrent headaches. Migraines and recurrent headaches.
• Nausea and vomiting.
• Anorexia.
• Gradual cognitive gradual.
• Pervasive developmental delay.
• Problems in learning and attention deficits.
• Alterations in the state of consciousness.
• Muscular and motor pathologies such as chronic fatigue, muscle weakness or hypotonia.
• Pathologies in the visual system such as optic atrophy, retinitis or decrease in visual acuity.
• Sensorineural deafness.
• Extreme sensitivity to temperature changes.

Other less common symptoms, but which may also appear during the course of the disease, are those related to the mental and psychological state of the person. These symptoms can be:

• Aggressive behaviors.
• Personality alterations.
• Obsessive-compulsive disorder.
• Anxious disorders.
• Psychosis.
• Affective disorders.

What causes it?

As mentioned at the beginning of the article, the MELAS Syndrome is a disease caused by a mutation in the mitochondrial DNA.. Therefore, it is a hereditary condition that is transmitted from the maternal genes.

These alterations occur in a number of specific genes located in the genetic material of the mitochondria. Most of these specific genes are responsible for transforming oxygen, sugars and fats into energy; while some others are involved in the production of tRNA molecules responsible for the construction of amino acid structures.

What is the treatment and prognosis?

At the moment, no specific treatment has been developed for MELAS syndrome, but rather specific treatments for each one of the symptoms presented by the patient, as well as a and a series of palliative care to improve the patient's quality of life.

Within the usual protocol, a group of specialists including neurologists, cardiologists, ophthalmologists, or endocrinologists, among many others, is in charge of developing a specialized treatment that is adapted to the symptoms and needs of the patient.

Unfortunately, these treatments fail to completely alleviate the effects of this condition, so that the person usually presents with progressive cognitive deterioration, followed by psychomotor problems, diminished hearing and visual abilities, and a whole series of medical complications until the patient's death.