Epidemiological differences between sepsis syndrome with bacteremia and culture-negative sepsis

OBJECTIVE: To explore the association of putative disease markers and poten tial risk factors with the nosocomial sepsis syndrome. DESIGN: Prospective case-control study matched for gender, age, and length of preinfection hospital stay. SETTING: 1,200-bed tertiary-care center in Spain. PATIENTS: Cases were selected using the sepsis syndrome criteria of the Ame rican College of Chest Physicians/Society of Critical Care Medicine Consens us Conference and were divided into three groups: sepsis with bacteremia (1 09 cases), sepsis with positive culture other than blood (122 cases), and s epsis with negative culture (115 cases without documented infection but wit h sepsis syndrome, clinically suspected infection, and empirical antibiotic treatment). Controls were randomly selected from the daily list of inpatie nts. Data were collected prospectively. Crude and multiple-risk-factor-adju sted odds ratios and their 95% confidence intervals were computed using con ditional logistic regression analysis. RESULTS: Presence of coma in the 48 hours before sepsis, intensive care uni t (ICU) stay, and decreased serum albumin levels at admission were common e pidemiological markers identified for the three groups of cases. Having a c entral venous catheter was the main healthcare-related risk factor for bact eremia. ICU stay and nasogastric tube were the main risk factors for sepsis with positive culture other than blood. Coma within 48 hours before sepsis and the need of intensive care were the only two markers identified for cu lture-negative sepsis. CONCLUSION: Culture-negative sepsis does not behave like culture-positive s epsis, and this may imply that implementation of preventive measures to dec rease the risk of bacteremia may not decrease the risk of sepsis syndrome ( Infect Control Hosp Epidemiol 2000;21:639-644).