Glycogenic thesaneurosis of the heart. It is a rare disease of genetic origin, which can produce symptoms from birth. It is one of the 11 types or subtypes of glycogenosis (type II) and is the only type in which involvement of the heart is an important characteristic.
The defect is due to the congenital absence of alpha 4-6 glucosidase from intracellular lysosomes (Hers). This causes the accumulation of normal glycogen in the lysosomal sacs, where it cannot be broken down by glycolytic enzymes.
Summary
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- 1 Pathological anatomy
- 2 Clinical signs
- 3 Diagnosis
- 4 Forecast
- 5 Treatment
- 6 Internal links
- 7 Sources
Pathological anatomy
There is always cardiomegaly , often of enormous proportions. The walls of both ventricles are thick and normal, those of the two atria. Histological examination checks infiltration of muscle fibers by large vacuoles filled with glycogen .
Deposits of varying amounts of glycogen are also found in the skeletal muscles, liver , kidneys, and Central Nervous System .
Clinical signs
In general, in the cases studied, signs were noticed already, from birth and in the first 12 hours of life, muted heart sounds, cardiomegaly and early signs of heart failure . More often the newborn appears normal, but then little weight gain is found, due to poor appetite and lassitude.
There may be noticeable hypotonia as well as macroglossia, and cardiomegaly is common. Systolic heart sound, often soft and variable, is noted. The liver is generally not hypertrophied.
The usual parameters for glycogen metabolism are normal, including glucose tolerance , response to adrenaline, and glucagon . These infants do not suffer from hypoglycemia . Radiological examination indicates gross generalized cardiomegaly, although it is not mandatory that the heart be hypertrophied at birth.
The electrocardiogram may show abnormalities at birth or after a period of a few weeks. An extraordinarily high voltage of QRS complexes and T waves is characteristic. There is evidence of left ventricular hypertrophy , however, a short PR interval is the most distinctive electrocardiographic feature of glycogen storage disease.
Diagnosis
The diagnosis is rarely established in the neonatal period , unless there is a family history of this disease. The first symptoms are unclear and do not indicate cardiac abnormality, except for intermittent episodes of dyspnea .
It is most likely several months before cardiomegaly is discovered. The diagnosis will be suspected in any child with increased cardiac size, especially when cardiomegaly is considerable; the presence of muscle weakness is another important manifestation.
The diagnosis of glycogen storage disease can be confirmed by demonstrating the increase of glycogen in a striated muscle biopsy, more easily, by examining the glycogen content in the lymphocytes of the blood .
Forecast
Death from heart failure almost always occurs before the end of the first year of life. Among the 23 cases that were chosen by Keith, Rowe and Vlad, 2 of the reviewed patients died during the first month of life.
Treatment
There is no known satisfactory treatment for this disease. In order to prolong life, Congestive Heart Failure in newborns and intercurrent infections will be combated.
