Virus-related acute renal failure: the clinical course and outcome of hemorrhagic fever with renal syndrome

A virus-induced kidney disease model based on organ-on-a-chip: Pathogenesis exploration of virus-related renal dysfunctions

Renal dysfunctions usually happen in viral infections and many viruses specially infect distal renal tubules, however the pathogenesis remains unknown. Here, in order to explore the pathogenesis of virus-related renal dysfunctions, a Pseudorabies Virus (PrV) induced kidney disease model was built on a distal tubule-on-a-chip (DTC), for the first time. The barrier structure and Na reabsorption of distal renal tubules were successfully reconstituted in DTCs. After PrV infection, results showed electrolyte regulation dysfunction in Na reabsorption for the disordered Na transporters, the broken reabsorption barrier, and the transformed microvilli. And it would lead to virus induced serum electrolyte abnormalities. This work brought us a new cognition about the advantages of organ-on-a-chip (OOC) in virus research, for it had given us a better insight into the pathogenesis of virus induced dysfunctions, based on its unique ability in function reproduction.

Pathogenetic and clinical aspects of the renal involvement in hemorrhagic fever with renal syndrome

Hemorrhagic fever with renal syndrome is the most common clinical manifestation of hantavirus infection. The main target organ is the kidney, resulting in an interstitial hemorrhagic nephritis and sometimes acute tubular necrosis. The pathogenesis is still largely unknown, but several recent studies indicate an important role for immune mechanisms including increased expression of cytokines, for example, tumor necrosis factor. Immunohistochemical studies of kidney biopsies have revealed deposits of IgG, IgM, and C3, but deposits were significantly less numerous than in chronic immune complex disease. Since hantaviruses are not cytolytic, a direct detrimental effect of the infecting virus is less likely. The long-term prognosis of hemorrhagic fever with renal syndrome seems to be favorable, but there are reports that previous hantavirus infection is associated with an increased risk of hypertensive renal disease. Prospective longitudinal studies addressing this issue are underway.

Acute renal failure due to hemorrhagic fever with renal syndrome

The aim of our study was to analyze the clinical course and outcome of acute renal failure (ARF) in patients with hemorrhagic fever with renal syndrome (HFRS). From 1983 to 1995, we treated 33 patients (27 males, 6 females) aged from 16 to 71 years. Half of patients were connected with work at a farm or in a forest. The disease was confirmed serologically with indirect immunofluorescence test (IFT) and enzyme-linked immunosorbent assay (ELISA). In 18 patients percutaneous kidney needle biopsies were analyzed. In 85% of the cases, the disease broke out from June to October. The most frequently expressed clinical signs and symptoms were fever, nausea/vomiting, headache, backache, abdominal pain, myalgia, diarrhea, conjunctival injection, and hemorrhages. Four patients had concomitant pancreatitis. In 25 patients, oliguria was present, and transient hemodialysis treatment was needed in 19 patients. Infection with Hantaan virus was established in 20 patients and with Puumala virus in 13 patients. At renal biopsy, acute interstitial nephritis accompanied with hemorrhages and necrosis was found, and at a later biopsy there were also signs of interstitial fibrosis. All patients were cured, but renal function was not completely recovered in some. We conclude that ARF is a serious complication in patients with HFRS. Although not lethal in our group of patients, many of them showed severe signs and symptoms of illness. Transient hemodialysis was necessary in two-thirds of the patients. Some degree of functional defects and morphological changes might persist.