What is Hemolytic Uremic Syndrome?
The term “hemolytic uremic syndrome” was introduced by a scientist Gasser et al, who observed in 1955 a child with hemolytic anemia and severe kidney damage. Similar descriptions existed before, however, Gasser first identified this form as a separate syndrome with a characteristic hematological, laboratory and pathological picture. Currently, more than 500 cases of hemolytic-uremic syndrome have been described, including in the domestic literature. The disease occurs in children aged 7 months to 15 years.
Symptoms of the Hemolytic Uremic Syndrome
The disease often begins suddenly after a child’s infection or vaccination. Sharp general weakness, pallor, abdominal pain, vomiting, and a decrease in the amount of urine appear. Body temperature rises. The liver and spleen are usually not palpable. Sometimes it is possible to probe the kidneys. Blood pressure rises only in the terminal phase of the disease. In the urine, red blood cells, white blood cells, sometimes free hemoglobin are found. Some time after the onset of the disease, urine ceases to be excreted.
Diagnosis of Hemolytic Uremic Syndrome
Anemia is noted, the hemoglobin content is below 70 g / l. Morphological changes in erythrocytes are expressed – a lot of destroyed red blood cells, schizocytes, red blood cells with spikes. Violations of the activity of red blood cell enzymes cannot be detected. Coombs direct and indirect tests are negative. Increased destruction of red blood cells is accompanied by leukocytosis with a neutrophilic shift and severe thrombocytopenia. Patients show a low level of fibrinogen, prothrombin VII and X plasma coagulation factors. This suggests intravascular coagulation in hemolytic uremic syndrome. Severe renal failure can develop at different times from the onset of the disease.
There are many descriptions of the histology of the kidneys in hemolytic-uremic syndrome. Detect the degeneration of capillary endothelial cells, deposits of fibrin-like material on their main membrane and fibrin with platelets in the lumen. In severe cases, renal infarction, fibrinoid necrosis of the wall of the arterioles are detected.
Currently, it is believed that with hemolytic-uremic syndrome, there is no auto-aggression against red blood cells and platelets. It is believed that the causative factor (microorganism, virus or vaccination) leads to the production of antibodies and the formation of antigen-antibody complexes. For an unclear reason, these complexes cause intravascular coagulation of blood with the formation of intravascular blood clots. This leads to increased fibrinogen consumption and platelet uptake. Red blood cells are probably mechanically destroyed by fibrin strands.
Treatment of Hemolytic Uremic Syndrome
Treatment of the syndrome should be aimed at eliminating intravascular coagulation, heparin is prescribed.
The formation of severe renal failure leads to the vital need for hemodialysis, which in some cases removes patients from an extremely serious condition.
Also, plasmapheresis is widely used to treat hemolytic uremic syndrome. An effect is noted with the introduction of freshly thawed plasma, which is not much inferior to plasmapheresis in efficiency.
The prognosis for hemolytic-uremic syndrome is serious, but with modern methods of therapy, mortality has decreased to 3-5%.