Maple syrup disease: a rare disease that leads to severe neurologic disorders

Maple syrup disease is a genetic disease that is associated with a disruption in the metabolism of amino acids such as leucine, isoleucine and valine. Their concentration in the body fluids increases, causing poisoning, ketoacidosis, seizures and even coma.

History

For the first time in the medical literature, the disease of maple syrup in adults was described in 1954 by the doctor Menkes. It received such a name because of the specific smell of urine in the patients. To researchers, it resembled burnt sugar or wood syrup. Another, more scientific name is the disease of branched acids.

It occurs approximately once for one hundred and fifty thousand newborns, since the type of inheritance of this gene is autosomal recessive. The disease is severe and often ends in death in childhood.

Etiology

For the development of the disease, both parents should be carriers of the defective gene responsible for the work of dehydrogenase of alpha-keto acids with branched chain. In nature, this enzyme is found in protein-rich foods such as eggs, milk, cheeses, poultry and others. The newborn develops organic acidemia, which is extremely dangerous for the nervous system.

The disease of maple syrup is more common in Jews, Amish, Mennonites. This is due to the fact that they live in a closed social group, and marriages most often occur between very distant relatives, which means that the probability of having a mutated gene responsible for the exchange of amino acids in parents increases at times.

Symptoms

Even in the second week after birth, you can reliably identify the disease of maple syrup. Symptoms are the unconventional behavior of the child: he constantly quietly cries, does not eat well, often and plentifully regurgitates, may even appear vomiting. With the progression of intoxication, convulsions appear, muscle tone grows. This manifests itself in the stretching of the child's body, as if "on the string," with legs crossed at the ankles. Up to the development of opisthotonus.

If parents continue to ignore the disease and do not call a doctor, the next stage of the disease is a violation of breathing and consciousness. Children become lethargic, lack of initiative, fall into a stupor, and then into a coma. Neurological disorders, even with a favorable outcome, remain for life. This is a fee for the fact that the disease of maple syrup was not diagnosed in time. Photos of patients are depressing, and the most sad, for the most part they depict children.

Diagnosis is based on the analysis of the presence in the urine of unfermented amino acids, as well as on clinical manifestations.

Classification

Depending on the intensity of manifestations and degree of inertness of dehydrogenase, several forms of the disease are distinguished:

1. Classical. Shortly after the birth of an apparently healthy child, just a few days later, symptoms begin to appear. First, this lack of appetite and rejection of the breast, then a decrease in body weight, periods of sleep apnea. Then, single clones, and then clonic-tonic convulsions. Comes to an end with a coma. The enzyme activity is below two percent.
2. Periodic. The disease does not manifest itself to half a year, and even up to two years of life. The trigger mechanism is a transferred bacterial or viral infection, vaccination or an excessive increase in the amount of protein in the food. Symptoms develop on increasing. The activity of the enzyme is up to twenty percent.
3. Thiamine-dependent. In its clinical manifestations is similar to the previous form. The essential difference is that the treatment uses vitamin B1, which significantly reduces the concentration of amino acids in urine and blood.

Treatment

Since a person enters the hospital in a state of severe poisoning, it is necessary to start treating the disease of maple syrup with detoxification. To do this, use plasmapheresis, peritoneal dialysis, transfusion of blood components, as well as forced diuresis and hemosorption.

After stabilization of the patient's condition, they begin to correct metabolic disorders. First of all, it is a diet with a reduced content of protein, sometimes it is recommended to refuse breastfeeding. Strict adherence to dietary rules will help to avoid further damage to the nervous system.

Modern technologies have virtually cured maple syrup disease. Science offers and introduces in practice drugs that will replace the necessary amino acids. They will maintain the metabolic rate within normal limits, not allowing poisoning even with a normal diet.

If the relevant recommendations are followed and a timely appeal to the hospital, a person can live a full life. Unfortunately, neurological disorders in children develop rapidly, and parents do not have time to take appropriate measures.