glycogen - it's hereditary diseases associated with inadequate content of a specific enzyme, receiving indirect participation in the process of glycogen synthesis and destruction.Due to the occurrence of the above violations conditions for excessive accumulation in the hepatic parenchyma and muscle glycogen.
Provided the proper functioning of the enzyme system of the human body, the process of breakdown of glucose, which in some cases in excess comes from food, involves the formation of a reserve of glycogen in the liver parenchyma and muscle fibers.Bystrotransformiruemoe Glycogen is a substance which, if necessary under reflux cleaved into glucose and entering it into the bloodstream.
main pathogenetic mechanism of glycogen storage disease is the occurrence of a defective enzyme involved in glycogen metabolism.As a result of these violations occur or excessive formation of glycogen and increased concentration in the tissues, or violation of its decay process
There is another form of glycogen, when on the contrary, the defective enzyme is not possible to synthesize glycogen and there is lack of maintenance in its "typical tissue accumulation", the so-called aglikogenoz.
glycogen storage disease symptoms
Some form of glycogen storage disease accompanied by severe symptoms of hypoglycemia due to impaired synthesis of glucose from glycogen stores of their own in those or other stressful situations.
glycogen storage disease in children observed more often than in the adult category of the population, as this disease belongs to the category of inherited congenital disorders and the debut of the clinical manifestations is the neonatal period.
Clinical manifestations of the disease are specific to each type of glycogen storage disease, but there is a large group of symptoms characteristic of all forms of this disease:
- progressive significant increase in the parameters of the liver, and in some cases the spleen, detectable by palpation, as well as via radial instrumental methods;
- generalized or limited decrease in muscle tone with increased convulsive readiness;
- a breathing disorder in the form of progressive dyspnea and hypoxia;
- focal neurological symptoms and cerebral nature;
- pronounced lag-type bone age of the passport and a complete lack of intellectual-mental disorders;
- nephropathy caused by excessive accumulation of uric acid, promotes the formation of stones in the renal pelvis system of kidneys.
Diagnostics glycogen storage disease of the newborn child in most situations it is not difficult, but to confirm the diagnosis recommended a study of glycemic and laktatemicheskogo profile of the patient, and in difficult cases the use of methods of biopsy of muscle or liver parenchyma in order to study the activity of enzymes taking indirect participation in the metabolic conversion of glucose.
Depending on the nature of the enzyme deficiency, as well as the predominance of accumulation of glycogen in muscle or liver parenchyma, can be divided into several glycogenoses all types.
glycogen and aglikogenozy relating to the type 0, accompanied by the development simptomkompleksa hypoglycemic coma occurring against the backdrop of the complete absence of a minimum reserve of glycogen in the liver parenchyma.
→ Gierke hereditary disease or glycogen storage disease type 1 is transmitted from generation to generation, provided that both parents will have the phenotypic manifestations of this disease or are carriers of the defective gene.The clinical syndrome that is caused by insufficient glycogenosis type of an enzyme involved in the breakdown and synthesis of glycogen in the mucosa of the small bowel, liver and kidneys.The debut appearance of clinical accounts for the neonatal period and accompanied by the development of respiratory distress syndrome, hypoglycemic convulsions, violation of digestion of food and indomitable gag reflex.During the short period of time, a child shows signs of growth glycogenic infiltration in the liver and kidneys, accompanied by a marked increase in their size and shape violation.Phenotypic characteristics of children with glycogen storage disease type 1, are: disproportsionalnost development of various parts of the body, delay the appearance of secondary sexual characteristics, generalized decrease in muscle tone.
→ autosomal recessive hereditary disease Pompe, or glycogen storage disease type 2 is characterized by rapidly progressive course and the emergence of the first symptoms of the disease in the first few days after birth.Severe disease with severe disorders of the functioning of all structures of the child's body due to the fact that the defect is an enzyme involved in the metabolic glycogen metabolism, observed not only in muscle tissue, but also in all the internal organs and blood cells.The hallmark of this form of glycogen storage disease is considered to be a defeat of the heart muscle, resulting in a marked hypertrophic cardiomyopathy and a significant increase in all the parameters of the heart.Signs of the respiratory system is the tendency to develop hypostatic pneumonia and segmental atelectasis, manifested symptoms of respiratory failure, and infectious and inflammatory symptoms.The most prominent manifestations of glycogen storage disease type 2 relate to muscle tissue and are characterized by the development of the clinic spastic myopathy (muscle tone reduction, the lack of response in the study of tendon reflexes, paralysis).
→ Cory hereditary diseases, or glycogen storage disease type 3, has traditionally had an autosomal recessive inheritance and is characterized by the appearance of the enzymatic defect in the liver, muscle, and blood cells.A special feature of this form of glycogen storage disease is the appearance of the characteristic clinical picture after a six-month age and significant regression of the disease after the child reaches the age of five, and therefore, this type of disease refers to diseases having the most favorable outcome.When glycogen storage disease type 3 are more affected the structure of the muscle fibers of skeletal muscles, so the main and sometimes the only manifestations are: limited weakness, hypotonia and hyporeflexia muscles.
→ glycogen storage disease type 4 or disease Andersen, characterized by severe progressive destruction of liver parenchyma with the development of irreversible changes in the form of proliferation of cirrhotic tissue, accompanied by severe violation of protein-synthetic and other vital functions of the liver.In addition to the inheritance of recessive manner there is a clear dependence on sex.
→ Miofosforilaznaya deficiency, or glycogen storage disease type 5, characterized isolated lesions of the muscle fibers of skeletal muscles, in this connection, the main manifestations of this type of pathology is a deformation of limbs due to uneven limited hypertrophy of muscle tissue in a particular area, as well as a pronounced convulsions.The occurrence of this type of glycogen storage disease is connected with gender, that is observed only in boys.Diagnosis of glycogen storage disease type 5 is not difficult, since the elementary analysis of urine and blood are characteristic changes (mioglobulinuriya transient and decrease in the concentration of lactate in the blood during the exercise test).
→ autosomal recessive hereditary disease Hers or glycogen storage disease type 6, will debut in infancy and is characterized by isolated liver with concomitant hyperglycemia and hyperlipemia.
→ glycogen storage disease type 7, Tarui or hereditary disease has symptoms similar to glycogen storage disease type 5.
→ 8 Feature of glycogen storage disease type or illness Thomson, is the defeat of the nervous system, damage to the liver parenchyma, resulting in the first year after the birth of the phenomenon is increasing cerebral and focal neurological symptoms.This pathology in recent years is extremely rare and has no connection with the type of genetic inheritance.
→ glycogen storage disease type 9 is found only in males and is characterized by an autosomal recessive mode of inheritance.The only manifestation of this disease is a progressive hepatomegaly.
→ glycogen storage disease type 10 represented by a single episode, so the fact that susceptibility to the transmission of this disease is not diagnosed and now this type of glycogen storage disease is not found.
→ glycogen storage disease type 11 is extremely rare and is accompanied by all the symptoms common to all forms of glycogen storage disease.A feature of this type is the appearance of a child's symptoms of rickets, due to a deficiency of phosphorus in the blood and the leveling of these symptoms with the onset of puberty.
priority in the treatment of glycogen storage disease type or that a correction and prevention of hypoglycemic symptoms medication and medication interventions.
Drug-free treatment involves correction of hypoglycemia feeding behavior with a preferred daily consumption legkorasscheplyaemyh types of carbohydrates and an increased quantity of proteins with simultaneous limitation of physical activity.
Considering the pathogenetic features of the disease, the patient should be prepared for the fact that a full recovery even with the use of all possible methods of treatment measures will not come.Therefore, therapeutic measures aimed at improving the well-being of the patient and prevent possible complications.
Each of the individual types of glycogen storage disease needs an individual approach to the treatment assignment.For example, children with glycogen storage disease type 1 shows the use of a water-soluble vitamin D (1-2 Akvadetrim cap. / Day. For the first year of life).Due to the fact that this type of glycogen storage disease is accompanied by the development of signs of nephropathy, it recommended reducing the concentration of uric acid, so it is advisable in this case the use of allopurinol.To prevent stone formation in the lumen of the gallbladder, which develops when the level of triglycerides in the blood needed is the appointment of nicotinic acid.Severe neutropenia requires correction purpose by a long course of colony-stimulating factor (filgrastim in the minimum daily dosage of 2.5 mg per kg of body weight of the child) with the necessary supervision of the treatment of laboratory diagnostic methods.
At present, in the era of genetic engineering techniques, is actively being developed drugs that could be used as replacement therapy glycogenosis.In the US and many European countries, the positive results of enzyme replacement therapy glycogen storage disease type 2 using Miozima at a dosage of 20 mg per kg body weight 2 p / month long course.This drug is aimed at reducing cardiomegaly, as well as improving the functioning of the muscular system.
Surgical treatment methods find their application only in the case of irreversible damage to the liver parenchyma observed in the 3 and 4 types of glycogen storage, and are to work liver transplantation.Muscle glycogen form, accompanied by a progressive myopathy and cardiomegaly, are not an indication for surgery.