The epidemiology of febrile reactions in haemodialysis.

Febrile reactions were studied in 2 000 consecutive haemodialyses performed in 85 patients. A number of 219 febrile reactions were registered in 49 patients (11%). The overall month-to-month incidence showed little variation. Febrile reactions were not distributed randomly among the patients; those with respiratory tract infection experienced more febrile reactions during periods with infection than during periods without. Similarly, the incidence was higher in patients with than without chronic urinary tract infection. A low incidence was registered both in patients under 40 years of age and in patients having had more than 100 dialyses at the beginning of the observation period. The frequency was the same whether single-pass or recirculating single-pass monitors had been used, and it was not influenced by blood transfusions during dialysis. Thus, our analysis leads to the conclusion that the majority of the febrile reactions registered among the present patients were determined by endogenous factors such as infection, while exogenous factors such as dialysate bacteria and pyrogens seem to have played only a minor role.