COLONIZAÇÃO DE CATETERES VENOSOS CENTRAIS POR BIOFILME MICROBIANO

The central venous catheters are very used in the Intensive Care Units (ICU). Their usage is often associated with complications including fatal infections. During January 2004 to January 2005, 118 catheter tips were analyzed as well as 42 blood samples from 100 patients who were in an ICU, in a Northwestern State of Sao Paulo Hospital. The study aimed was to analyze, through the culture and scanning electron microscopy search, the central intravenous catheter colonization of Intracath Vialon of a single lumen. To detect the slime production of the isolated microorganism, it was used the method of Christensen et al. (1985) and the sensitivity profile to the antimicrobials according to (NCCLS-M2-A7-2000). From the 118 studied catheters tips by the semi-quantitative method, 34 (28.8%) were colonized (≥15 UFC/plaque) where 55 microorganism were isolated. From 32 (58.2%) were classified as Grampositive with a major frequency to 15 (27.3%) Staphylococcus aureus, six (10.9%) Staphylococcus epidermidis; 19 (34.5%) classified as Gram-negative with a major frequency to six (10.9%) Acinetobacter baumannii, three (5.4%) Pseudomonas aeruginosa, Enterobacter aerogenes respectively and still, four (7.3%) classified as yeast including two (3.6%) Candida albicans and two (3.6%) Candida parapsilosis. The quantitative method showed that 34 (28.8%) of the tips were colonized (≥ 10 UFC/ml) where 52 microorganisms were isolated. From those, 32 (61.6%) were classified as Gram-positive with a major frequency to 16 (30.8%) Staphylococcus aureus, five (9.6%) Staphylococcus epidermidis, 19 (36.5%) classified as Gramnegative with major frequency to five (9.6%) Acinetobacter baumannii, four (7.7%) Enterobacter aerogenes and three (5.8%) Pseudomonas aeruginosa, and still one (1.9%) classified as yeast Candida albicans. From the 42 blood cultures, four (9.5%) showed microbial development. From those isolated four microorganisms, being two (50.0%) Staphylococcus aureus, one (25.0%) Citrobacter freundii and one (25.0%) Stenotrophomonas maltophilia. The slime production test was realized with 130 strains from which 86 (66.2%) were Gram-positive and 44 (33.8%) Gram-negative. The slime production was detected in 45 (34.6%) Gram-positive bacteria strains among 37 (28.5%) were Staphylococcus aureus and eight (6.2%) Staphylococcus epidermidis. The study of the 34 colonized tips (≥15 UFC/plaque and or ≥10 UFC/ml) in relation to the outside surface of the catheter tips eight (23.5%) showed adherent microorganisms, while the outside surface, 24 (70.6%) showed adherent microorganisms. The microorganisms responsible for the related bacteremia to the catheter in four patients were two (50.0%) Staphylococcus aureus, one (25.0%) Citrobacter freundii and one (25.0%) Stenotrophomonas maltophilia. The sensitivity test to the antimicrobial agents of 37 strains of Staphylococcus aureus showed sensitivity (100.0% to teicoplanin and vancomycin), five (10.5% to rifampin), intermediary 14 (42.1% to rifampin) and resistency (100.0% to gentamicin, chloramphenicol, ciprofloxacin, levofloxacin, clindamycin, erythromycin, oxacillin, penicillin G, sulphazotrin, tetracyclin and 18 (48.7% to rifampin).