Serum Antibodies Reactant with Korean Haemorrhagic Fever Agent in Scandinavian Endemic Benign Nephropathy (Nephropathia Epidemica) Demonstrated by Immunofluorescence Utilizing an in vitro Antigen Source.

A newly developed spot slide immunofluorescence method utilizing an in vitro antigen source was used for the first time for the assay of antibodies reactant with the Korean haemorrhagic fever (KHF) agent in sera from patients diagnosed with Scandinavian endemic benign (epidemic) nephropathy (nephropathia epidemica, EBN) and from 42 age-matched control patients living in the same area but suffering from other maladies. KHF antibodies were demonstrated in all of 14 EBN patients who were followed prospectively, 7 of whom exhibited seroconversion, and in 6 of 8 EBN patients studied retrospectively, but in only one of the 42 controls. Similar to that seen in KHF, antibodies in EBN appeared within the first week of onset of symptoms and persisted for long periods of time. The time from the onset of the illness until maximal antibody titre was recorded varied from 9 days to 1 month. On average, the level of the antibody titres measured to EBN was lower than that usually encountered in the Korean disease. The results indicate a close antigenic relationship between the KFH and EBN agents and demonstrate that the reliability of our new spot slide method is similar to that of another previously reported and more laborious immunofluorescence method using lung sections from infected rodents as antigen source. (Author)