Objectives: This article reviews published studies of nursing home-acquired BSI in North America to determine whether there have been changes in the epidemiology of this infection in the past 20 years and to define indications for blood cultures in the nursing home setting.
Methods: A Medline search was conducted for the period from 1980 to August 2003.
Results: Seven studies of nursing home-acquired BSI were identified. The incidence of nursing home-acquired BSI was low (0.3 episode per 1,000 resident care-days). Sources of BSI changed little during the past two decades, with urinary tract infection representing approximately 50% of the episodes. The bacteriology also did not change substantially during the past 20 years; gram-negative bacilli were isolated in approximately 50% of the episodes and Escherichia coli was the most commonly isolated organism. In the most recent study, covering the period 1997-2000, resistance to fluoroquinolones and broad-spectrum penicillins and cephalosporins was uncommon among gram-negative blood isolates; MRSA was the most common resistant organism causing nursing home-acquired BSI. Case-fatality rates changed little during the past 20 years; urinary tract infection was associated with the lowest mortality and pneumonia had the highest case-fatality rate.
Conclusion: There has been little change in the epidemiology of nursing home-acquired BSI in the past 20 years. Given the low incidence of BSI and the low overall yield of positive results of blood cultures (probably < or = 6%), there is currently no support for the routine use of blood cultures in the nursing home setting.