Association of HLA B27 with benign clinical course of nephropathia epidemica caused by Puumala hantavirus.

Both the severe course of nephropathia epidemica (NE) caused by Puumala hantavirus, and the fast progression of human immunodeficiency virus (HIV) disease, are associated with the HLA B8 DRB1*0301 haplotype. As HLA B27, on the contrary, is associated with the slow progression of HIV disease, we wanted to test whether the same is true for NE. Only six (8%) NE patients, half the figure expected, had the HLA B27 allele in 74 randomly selected hospital-treated patients. All six had a benign overall clinical course of NE; none had any severe complications, the severity of renal failure was also mild, and the treatment time at the hospital was half that needed for HLA B27- patients (P = 0.004). Patients who were HLA B27 had maximal blood leucocyte count > 10.000 x 10(9)/L (P = 0.020) more often, probably reflecting differences in immune response. Thus, similar HLA associations can be found in both HIV infection and NE caused by Puumala virus.