Pearson syndrome it is a strange disease which, although it is only known in less than a hundred cases worldwide, has attracted the interest of geneticists and molecular biologists since its discovery in the 1970s.
In this article, we’ll dig deeper into this rare condition by knowing its symptoms, causes, diagnosis, and treatment.
What is Pearson Syndrome?
Pearson syndrome is a disease of genetic origin, caused by DNA alterations found in the mitochondria. This alteration is due in most cases to mutations occurring during cell division during the formation of the embryo.
Being a disease caused by something that is inside every cell in the body, there is no known way to cure it besides presenting a very poor prognosis being people diagnosed with Pearson children who will rarely live more than three years.
The problems derived from this rare disease are diverse, being the main ones of hematological, hepatic and muscular type. All of this leads to a limited ability of the individual to interact with the world around him, in addition to presenting growth problems.
The first person to describe it was its name, Howard Pearson in 1979. This disease it is so rare that to date barely seventy cases are known in the international literature.
Pearson syndrome is genetic in origin. It occurs as a result of DNA damage inside the mitochondria, the organelle responsible for cellular respiration. This alteration can be due either to a deletion, that is to say to the partial or total loss of the DNA molecule, or to a duplication, that is to say to a region of the DNA in replication course. These alterations are due, in most cases, to mutations in the genetic material of the individual.
These alterations lead to a metabolic effect, make the cell not receive energy properly, Which ultimately affects the fundamental and vital processes of the organism, such as the active transport of substances in the cell, muscle contraction, the synthesis of molecules, among others.
The clinical presentation of Pearson syndrome is variable, so it is necessary to follow a rigorous follow-up of the patient to confirm that he has the disease, as well as to find out what are the main problems that the individual in question suffers from., Because as for any other disease, the symptoms from one patient to another may be different. The main diagnostic tool for this syndrome is a molecular biochemical study, In which we will see whether or not he has the alteration of mitochondrial DNA.
In most cases, genetic testing can only be done after the baby is born and the first symptoms possibly associated with Pearson syndrome in the particular case are detected. Although prenatal screening to detect the syndrome is theoretically possible, analyzing and interpreting the results is a really difficult thing, as well as risky for the life of the still developing fetus.
The first symptoms of the syndrome appear during the first year of life, being one of the most striking problems in the blood and pancreas. In most cases, individuals do not live longer than three years.
In this syndrome, there are problems in the bone marrow, which involves problems in the blood. The bone marrow does not produce white blood cells (neutrophils) efficiently (pancytopenia), which leads the individual to develop anemia, which can progress very severely. In addition, he presents with platelet count and aplastic anemia.
With regard to the pancreas specifically in its exocrine part (exocrine pancreatic insufficiency), in this syndrome there is a dysfunction of this organ, causing greater atrophy of it.
Because of that, people with Pearson syndrome have trouble absorbing nutrients from food, This leads to nutritional problems that present growth problems and difficulty in gaining weight, in addition to fairly frequent diarrhea.
But besides the 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.
- Hepatic insufficiency.
- Neuromuscular disorders and myopathies.
- Heart problems.
- Atrophy of the spleen.
Pearson syndrome, as we have already seen, is genetic in origin, as it consists of an alteration of mitochondrial DNA. This, with the therapeutic tools available to current medicine, is not possible to solve and, therefore, this syndrome has no known cure.
However, this does not mean that treatment cannot be applied to the person who has this medical condition. even if therapy is focused on relieving symptoms, With little chance of causing a significant change in its manifestation, it is an ideal treatment for improving the patient’s quality of life, as well as directly reducing or preventing the onset of other problems that may be secondary to the syndrome. Pearson, such as infections.
Among the problems associated with the syndrome is Earns-Sayre syndrome, Which leads to an impaired retina, hearing loss, diabetes and cardiovascular disease. Other problems include sepsis, endocrine disorders, crisis of lactic acidosis production, and liver errors. All these pathologies, associated with the syndrome, contribute to the fact that children with this diagnosis do not have a much longer life expectancy at three years.
People who manage to survive to infancy progress with hematologic signs that resolve spontaneously, while neurologic and muscle problems arise and worsen. If they’ve never had Kearns-Sayre syndrome before, kids will likely end up having it after they’re over three years old.
It should be noted that yes there is a surgical intervention that can significantly improve the patient’s life, even if its goal is palliative. It is a bone marrow transplant because the syndrome has a very marked effect on the bone marrow and this type of intervention allows you to lengthen your life a little longer. If this option is not possible, blood transfusions are usually very frequent, especially to avoid severe anemia, associated with treatment with erythropoietin.
- Cammarata-Scalisi, Francisco and López-Gallardo, Ester and Emperor, Sonia and Ruiz-Pesini, Eduardo and Silva, Glòria and Camacho, Nolis and Montoya, Julio. (2011). Pearson syndrome: a case report. 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 vacuolation of spinal cord precursors and exocrine pancreatic dysfunction. J Pediatr 1979; 95: 976-984.