[Febrile episodes in elderly inpatients--a one year survey to determine the causes of fever in hospital].

To determine the cause of nosocomial infections, all febrile episodes of hospitalized elderly patients aged 65 and older at a hospital in Fukuoka City were categorized between April 15 1994 and April 14 1995. A febrile episode was a temperature above 37.5 degrees C after 7 consecutive days of normal body temperature (below 37.5 degrees C). Various clinical tests including blood examination, urinalysis, chest radiography and bacterial culture were done on the first and 7th day of the fever. A total of 1105 episodes in 443 patients (male 136, female 307) fulfilled this criteria for fever. The fevers were mainly due to respiratory tract (381 cases, 34.5%) and urinary tract infections (263 cases, 23.8%). There were 135 infections (12.2%) of other kinds and 297 cases (26.9%) that were classified as unknown. Approximately 70% of the febrile episodes were caused nosocomial infections, suggesting increased risk of infection in the hospitalized elderly and the importance of early detection of febrile changes in elderly inpatients.