Objective: to summarize rates of resistance in the most common pathogens associated with nosocomial infections among ICU patients, and to provide the secular trend of these rates after fifteen years of surveillance.
Methods: prospective surveillance of NNIS patients according to the ICU NNIS/NHSN component in seven Brazilian hospitals. The concepts of CDC have been used to characterize patients with NI.
Results: from a period of time that varies from 12 months in one ICU and fifteen years in two ICUs (jan./94 to dec./08) we diagnosed 7,253 NIs that had definition of at least one pathogen: 775 blood stream infections (BSI = 11%); 3,016 pneumonias (PNEU = 42%); 1,260 urinary tract infections (UTI = 17%); 373 surgical site infections (SSI = 5%) and 1,829 others infections (OTHER = 25%). Nine pathogens were responsible for 81% of all NIs: Pseudomonas aeruginosa (15%); Staphylococcus aureus (12%); Acinetobacter spp. (12%); Coagulase-negative staphylococci (9%); Escherichia coli (8%); Klebsiella pneumoniae(8%); Enterobacter spp.(7%); Candida spp. (6%); Enterococci spp. (4%). The rates of resistance in the most common pathogens associated with nosocomial infections in these ICU patients, comparing 1994-2001 data versus 2002-2009, were: Staphylococcus aureus resistant to Methicillin (53% to 51%); Coagulase-negative staphylococci resistant to Methicillin (60% to 83%); Enterococci spp. resistant to Vancomycin (0% to 13%); Enterobacter spp. resistant to Third-generation cephalosporins (38% to 67%); Klebsiella pneumoniae resistant to Third-generation cephalosporins (44% to 48%); Pseudomonas aeruginosa resistant to Imipenem (4% to 44%); Pseudomonas aeruginosa resistant to Third-generation cephalosporins (33% to 67%);Pseudomonas aeruginosa resistant to Ciprofloxacin/ofloxacin (20% to 52%).
Conclusions: all ICUs analyzed showed an emergence of antimicrobial-resistant pathogens that has made treating of NI very difficult and, in some cases, impossible. MRSA, a pathogen with very specific control measures in these hospitals, had its rate stabilized after all these years.