Pearson syndrome: what it is, symptoms, causes and treatment

Pearson's syndrome It is a rare medical condition that, despite only knowing less than a hundred cases worldwide, has aroused the interest of geneticists and molecular biologists since it was discovered in the seventy.

In this article we are going to delve into this rare disease, knowing its symptoms, causes, diagnosis and treatment.

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What is Pearson syndrome?

Pearson's syndrome is a disease of genetic origin, caused by alterations in the DNA found within the mitochondria. This alteration is due in most cases to mutations that occurred during cell division when the embryo is being formed.

Being a disease caused by something that is found within each of the body's cells, there is no known way to cure it, in addition to presenting a very poor prognosis, with individuals diagnosed with Pearson being children who will rarely live more than three years.

There are several problems derived from this rare medical condition, the main ones being hematological, hepatic and muscular. All this leads to a limited ability of the individual to interact with the world around him, in addition to presenting problems in growth.

The first person to describe it was after whom it is named, Howard Pearson in 1979. This sickness It is so rare that, to date, only about seventy cases are known in the international literature..

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Causes

Pearson syndrome is genetic in origin. It occurs as a consequence of an alteration in the DNA inside the mitochondria, an organelle that is in charge of cellular respiration. This alteration can be due either to a deletion, that is, the partial or total loss of the DNA molecule, or to duplication, that is, that a region of DNA is replicated. These alterations are due, in most cases, to mutations in the genetic material of the individual.

These alterations cause that there is affectation in the metabolism, causing the cell to not receive energy correctly, which ultimately affects basic and vital processes for the organism, such as active transport of substances in the cell, muscle contraction, the synthesis of molecules, among others.

Diagnosis

The clinical presentation of Pearson syndrome is variable, which makes it necessary to follow a rigorous follow-up of the patient to confirm that he has the condition, in addition to find out what are the main problems suffered by the individual in question, given that, as with any other disease, the symptoms from patient to patient can be different. The main diagnostic tool for this syndrome is a biochemical-molecular study., in which it will be seen whether or not it has the alteration in mitochondrial DNA.

In most cases, genetic tests can only be done once the baby is born and the first symptoms that are possibly associated with the Pearson syndrome of the case are detected concrete. Although prenatal testing for the syndrome is theoretically possible, analyzing and interpreting the results is something really difficult, as well as risky for the life of the fetus still in formation.

Symptoms

The first symptoms of the syndrome appear during the first year of life, being one of the most striking blood and pancreas problems. In most cases, individuals do not manage to live more than three years.

In this syndrome there are problems in the bone marrow, which implies problems at the blood level. The marrow does not produce white blood cells (neutrophils) efficiently (pancytopenia), which causes the individual to end up developing anemia, which can evolve very seriously. He also presents low platelet count and aplastic anemia.

In relation to the pancreas, specifically to the exocrine part of it (pancreatic insufficiency exocrine), in this syndrome there is a dysfunction in this organ, causing a greater atrophy of the same.

Because of this, individuals with Pearson syndrome have problems absorbing nutrients from food, which leads to nutritional problems that result in growth problems and difficulty gaining weight, in addition to having diarrhea quite frequently.

But in addition to problems in the blood and pancreas, there are many other symptoms that define this disorder, which is considered a multisystem mitochondrial disease. Some of these symptoms are:

• Refractory sideroblastic anemia.
• Defective oxidative phosphorylation.
• Renal and endocrine failure.
• Liver failure.
• Neuromuscular disorders and myopathies.
• Heart problems.
• Spleen atrophy.

Treatment

Pearson syndrome, as we have already seen, is of genetic origin, since it consists of an alteration of mitochondrial DNA. This, with the therapeutic tools that current medicine has, it is not possible to solve it and, therefore, this syndrome has no known cure.

However, this does not mean that a treatment cannot be applied to the person who has this medical condition. Yes ok The therapy is focused on alleviating the symptoms, with few possibilities of implying a significant change in its manifestation, it does represent an ideal treatment to improve the quality of life of the patient. patient, in addition to reducing or directly preventing the appearance of other problems that may be secondary to Pearson syndrome, such as infections.

Among the problems associated with the syndrome is Earns-Sayre syndrome., which supposes a deterioration in the retina, hearing loss, diabetes and cardiovascular diseases. Other problems include sepsis, endocrine disorders, lactic acidosis production crisis, and liver failure. All these pathologies are those that contribute, combined with the syndrome, to the fact that children with this diagnosis do not have a life expectancy much longer than three years.

Those individuals who manage to survive the earliest infancy evolve showing hematological signs. that resolve themselves spontaneously, while neurological problems and muscular problems arise and go to worse. If they have not presented Kearns-Sayre syndrome before, children will surely end up presenting it after they have exceeded three years of age.

It should be noted that yes there is a surgical intervention that significantly improves the patient's life, even if its purpose is palliative. It is a bone marrow transplant, since the syndrome affects the marrow in a very marked way and this type of intervention allows you to extend your life a little longer. If this option is not possible, blood transfusions are usually very frequent, especially to avoid severe anemia associated with erythropoietin therapy.

Bibliographic references:

• Cammarata-Scalisi, Francisco & López-Gallardo, Ester & Emperador, Sonia & Ruiz-Pesini, Eduardo & Silva, Gloria & Camacho, Nolis & Montoya, Julio. (2011). Pearson syndrome: report of a case. Clinical research. 52. 261-267.
• Pearson HA, Lobel JS, Kocoshis SA, Naiman JL, Windmiller J, Lammi AT, Hoffman R, Marsh JC. (1979) A new syndrome of refractory sideroblastic anemia with vacuolization of marrow precursors and exocrine pancreatic dysfunction. J Pediatric 1979; 95:976-984.