HEMORRHAGIC FEVER WITH RENAL SYNDROME
HEMORRHAGIC FEVER WITH RENAL SYNDROME (syn: hemorrhagic nephrosonephritis) is an infectious disease characterized by fever, kidney damage and, in some cases, the development of hemorrhagic syndrome.
The causative agent is a virus. The source of the causative agent of the infection is rodents (red vole, large vole, field and forest mice, etc.) that secrete the virus with urine and feces. Human infection occurs by airborne dust when inhaled with air dust containing dried particles of rodent feces, as well as by alimentary and through damaged skin on hands in contact with rodents and their feces. The increase in the incidence occurs in the summer and autumn months, which is due to field work, a massive departure of citizens outside the city, rodent migration, etc. Diseases are recorded in forest and forest-steppe zones, floodplain forests of the steppe zone of European Russia, the Far East, some European countries and Of Asia.
The clinical picture. The incubation period lasts 4–49 days, more often 14–21 days. Usually, the disease begins acutely, less often the onset of the disease is preceded by a prodromal period: weakness, weakness, chills, discomfort when swallowing, minor pain in the muscles, joints, low-grade fever. During the disease, four periods are distinguished - febrile, oliguric, polyuric, convalescence.
The febrile period (1-3rd day of illness) is characterized by a rapid increase in temperature to 38-40 ° C, chills, headache, pain in the muscles of the back and lumbar region, photophobia, dry cough. On examination, bright hyperemia of the face, neck, upper chest, vascular injection of the sclera and conjunctiva ("rabbit eyes"), hyperemia of the throat, and petechiae on the mucous membrane of the hard palate are revealed. During the oliguric period (from the 4th to the 8th-12th day of illness), the temperature decreases, but the patient's condition worsens. Pain in the lower back increases (sometimes they become unbearable), vomiting often appears, diarrhea is possible, the liver and spleen increase. The patient's face is puffy, the eyelids are pasty, the skin is pale. The amount of urine secreted progressively decreases up to anuria. On palpation in the lumbar region there is a sharp pain. A picture of acute renal failure develops. On the 3rd – 6th day of illness, patients (mainly with severe acute renal failure) often show signs of a hemorrhagic syndrome: petechial rash, mainly on the chest, hemorrhages in the sclera, nose and intestinal bleeding.
The polyuric period (from 9–13 to 20–24 days) is characterized by an increase in diuresis (up to 3-5 liters per day or more), which indicates recovery, lower back pain gradually subsides, vomiting stops, sleep and appetite are restored . Thirst, weakness are expressed. Significantly reduced urine density.
The period of convalescence is slow, with a gradual restoration of renal function, accompanied by prolonged asthenia, lability of the cardiovascular system.
The diagnosis is established on the basis of an epidemiological history (contact with rodents, rodent migration to settlements), the clinical picture and laboratory tests of blood and urine. Leukopenia is revealed in the blood, which is replaced by neutrophilic leukocytosis, an increase in the number of red blood cells and a decrease in the number of platelets, a significant increase in ESR, an increase in the content of residual nitrogen. In the urine, the amount of protein increases significantly, cylinders appear, blood, the relative density of urine is reduced.
Treatment is carried out in a hospital. Patients need complete peace. A milk and vegetable diet is prescribed. There are no specific treatment methods. With the threat of acute renal failure, prescribe prednisone , antihistamines, and protease inhibitors. According to indications, hemodialysis is carried out, heparin is used. Discharge patients from the hospital after the disappearance of the main clinical manifestations.
The forecast is serious, mortality is 1 - 10%.
Prevention is aimed at the extermination of rodents in natural foci, to exclude people from contact with rodents and their feces and the possibility of contamination of rodents with food and water. If it is necessary to place people on the ground in natural foci, they choose places that are not inhabited by rodents, such places are cleaned of weeds, grass, shrubs, and deadwood.