Urine excreted antibodies significance in the hemorrhagic fever with renal syndrome specific diagnosis

Abstract

Relevance. Hemorrhagic fever with renal syndrome (HFRS) is an acute viral zoonosis. Being widespread in Eurasia, it occupies a leading place in Russia among natural focal human diseases. The vast majority of HFRS cases in Russia, about 98%, are associated with Puumala virus. The disease characterized by a wide range of clinical manifestations. Early specific diagnostics appears to be of a great importance for starting timely pathogenic therapy.The aim of the study was to clarify the diagnostic value of hantavirus antibodies detection in the HFRS suspected patients urine. Materials and methods. Blood sera and urine samples from 68 patients of the Infectious Diseases Hospital in Ufa, obtained with a 2-day interval, as well as urine and blood serum samples of 15 convalescents after 1, 2, 3 and 6 months of disease onset were examined for hantavirus antibodies. 53 blood sera and urine samples from Moscow, Moscow and Samara regions patients taken at different times over the disease course were investigated in parallel. Antibodies were detected by the indirect immunofluorescence method.Results. On the 3rd, 4th, 5th and 6th days of illness, in the presence of antibodies in the blood serum, antibodies in the urine were detected in 85.7%, 89.4%, 93.1% and 100% of patients, respectively. The vast majority amount of antibodies was excreted in the urine from 5 to 11 days, which corresponds with the oliguric stage of the disease. In the convalescent period, antibodies were still detected in urine after 1, 2 and 3 months in 86.7%, 46% and 20% of cases, respectively, and were not detected after 6 months, which probably reflects the process of long-term restoration of the kidneys function. A moderate positive correlation of antibodies in serum and urine was observed only in the oliguric period of the disease.Conclusions: Detection of hantavirus antibodies simultaneously in blood serum and urine of febrile patients instead of paired blood sera investigation provides HFRS diagnosis in the very first days of hospitalization and prevent severe complications due to timely pathogenic therapy.