Caracterização das infecções hospitalares ocorridas em um hospital de ensino do Norte do Paraná, Brasil

Abstract

Hospital infections, especially those caused by multi resistant microorganisms, have been a problem not only in Brazil but in many other countries, and the knowledge of their epidemiology is an important tool for proposing prevention e and control measures. This descriptive and retrospective study aims at characterizing hospital infections that occurred between 2000 and 2005 in a Public School Hospital in the northern region of Paraná, Brazil. The 290-bed tertiary health institution is a reference center of the National Health Service and receives patients from various regions of Paraná State as well as from other States. Data were obtained from the databank of the Hospital Infection Control Commission, which uses software called Automated Hospital Infection Control System for information storage, and from the databank of the clinical laboratory, which stores information on hospital infections on Microscan® Automated System. For the epidemiological surveillance of hospital infections the methodology of The National Nosocomial Infection Surveillance System is observed. The average 6.06% incidence rate of hospital infection over the period is lower than the range of 9 to 20% accepted by the World Health Organization. It is also lower than those found in studies accomplished in Brazil and abroad. Staphylococcus aureus, with a 6.79% incidence rate, was the most prevalent pathogen of hospital infections, reinforcing other studies that have highlighted the importance of this species in nosocomial infections? etiology. Pseudomonas aeruginosa, with a 6.2% incidence rate, and Staphylococcus epidermidis with 6.15% were bacterial species that received a prominent place in hospital infections? etiology. Candida sp., with 5.14%, gradually increases its involvement as several studies have shown. Respiratory infections reached the highest incidence rate, followed by the urinary tract, surgical site, skin and soft tissues. Among the respiratory infections, pneumonia represented almost all of the cases. This finding is important as pneumonia is the main cause of death among hospital infections. S.epidermidis reached the highest incident rate for respiratory infections; for urinary tract infections, Candida sp. was most prevalent, while S.areus was most prevalent for surgical sites. The antimicrobial susceptibility test showed that most of the bacterial species involved in the hospital infections' etiology were multi resistant to the drugstested, highlighting the necessity of implementing prevention and control measures. All the evaluated S. aureus samples were sensitive to vancomycin and only 27% to oxacillin. Vancomycin represents one of the last recourses for treating hospital infections caused by multi resistant S. aureus and the resistance to oxacillin is a marker of multi resistance. The average 15.07% lethality rate is in accordance with literature and its annual profile is similar to the one observed for the average annual incidence rates of hospital infections. The incidence rates of hospital infection in different institutions may vary significantly for they are directly related to the degree of care and complexity of each.