No abstract

This study sought to reevaluate the epidemiology of bloodstream infection in nursing home residents. The records of 166 nursing home residents admitted to an urban, public, university-affiliated hospital with 169 episodes of bloodstream infection between January 1997 and April 2000 were retrospectively reviewed. The most common organisms isolated were Escherichia coli (27% of isolates), Staphylococcus aureus (18%; 29% were methicillin-resistant strains), and Proteus mirabilis (13%). There was minimal resistance to quinolones and third-generation cephalosporins among aerobic gram-negative bacilli. The most common sources were the urinary tract (51% of episodes) and the lungs (11%); a source was not identified in 22% of episodes. Hospital mortality was 18%. Independent predictors of hospital mortality were a pulmonary source of infection, systolic blood pressure <90 mm Hg, and leukocytosis >20,000 cells/mm3. Compared with other studies published in the past 2 decades, mortality was lower. The most common resistant organism was methicillin-resistant S. aureus.

The objectives of this study were to define the epidemiology of nosocomial bacterial colonization and infection and to define predictors of nosocomial infection among a cohort (n=423) of admissions to an acute rehabilitation unit. Overall, methicillin-resistant Staphylococcus aureus (MRSA) and enterococci were the most commonly identified colonizing organisms. Escherichia coli and Pseudomonas aeruginosa were the most commonly identified colonizing gram-negative bacilli. During 70 (16.5%) of the 423 hospitalizations in the unit, 94 nosocomial infections occurred. The most common infections were those of the urinary tract (30% of 94 infections) or a surgical site (17%), Clostridium difficile diarrhea (15%), and bloodstream infection (12.8%). Antibiotic-resistant bacteria most commonly caused bloodstream infection (41.7%) and surgical site infection (56.3%). Independent predictors of nosocomial infection at the time of admission were functional status (measured with the functional independence measure), APACHE III score, and spinal cord injury. In conclusion, gram-positive organisms were the predominant strains causing nosocomial colonization and infection. The logistic model, if verified, may be useful in defining patients who should be targeted for measures to prevent nosocomial infection.

The findings of this study have implications for the diagnosis and management of suspected pneumonia in nursing home residents but require prospective validation.