PREVALENCE AND ANTIMICROBIAL SUSCEPTIBILITY OF MICROORGANISMS ISOLATED FROM BLOODSTREAMS IN HOSPITALIZED PATIENTS AT THE UNIVERSITY HOSPITAL OF LONDRINA

Nosocomial bloodstream infections are an important cause related to a high morbidity and mortality in Brazilian hospitals, mainly for critically ill patients, especially because of a high antimicrobial resistance rate. The objective of this study was to evaluate the etiology and the antimicrobial susceptibility of microorganisms isolated from aerobic positive peripheral bloodstreams of patients hospitalized at Londrina University Hospital from January 2013 to December 2017. Hemoculture samples were incubated and monitored by automated BACTEC™ System and the identification and sensitivity profile of the microorganisms were performed by Automated System ObservaVitek®2 (bioMérieux). Data were obtained through the Labhos System of hospital management information. During this period, 2,397 peripheral aerobic bloodstreams were positive, being 41% positive for fermentative and non-fermentative gram-negative bacillus (977), 58% for gram positive cocci (1,397) and 1% for fungi (23). The most commonly found microorganisms were Staphylococcus epidermidis (20%), Staphylococcus aureus (14%), Klebsiella pneumoniae (11%), Acinetobacter baumannii (6%) and Staphylococcus haemolyticus (6%). The age of the patients ranged from 0 to 98 years old, with 1394 males and 1003 females. When evaluating the sensitivity profile of these isolates, among the most frequent gram-negative bacillus, the drugs that showed the highest sensitivity rates were amikacin (68%), tigecycline (62%) and meropenem (43%). Among gram positive cocci, the drugs with highest sensitivity rates were rifampicin (84%), sulfamethoxazole + trimetoprim and gentamicin (56%). Still among gram-positive cocci, the most resistant antimicrobials were erythromycin (74%) and clindamycin (69%). In addition to these, there was a high rate of resistance to oxacillin among gram positive cocci, being 97% for S. haemolyticus, 69% for S. epidermidis and 41% for S. aureus. Although meropenem is among the most sensitive antimicrobials, we have also seen a considerable rate of resistance to carbapenems, both to K. pneumoniae and A. baumannii, respectively (42% and 85%). We concluded that gram positive microorganisms were the most frequent pathogens. About the susceptibility to antimicrobials, aminoglycosides and glycylcyclines showed the highest sensitivity rates for both gram-negative bacillus and gram-positive cocci. On the other hand, the rate of resistance to carbapenems was high for A baumannii and K. pneumoniae, as well as oxacillin rates were high for Staphylococcus spp, especially coagulase negative. These data are of concern because these drugs are widely used in these cases, thereby reducing the therapeutic options and making the patients' clinical management more difficult.