Abstract:
Central venous catheter-related blood stream infection (CRBSI) is associated with high rates of morbidity and mortality in critically ill patients. This study was conducted to determine the incidence of central venous catheter-related infections (CRIs) according to different access sites, isolation, identification and determination of the predominant microorganisms involved and to determine the risk factors for infection by statistical analysis of the results to contribute the elaboration of actions to prevent and control blood stream infections and mortality among those patients. A total of 160 adult patients with indwelling central venous catheters hospitalized at intensive care units (ICUs) were enrolled in this study. A total of 640 clinical samples were collected from the patients; 4 different samples collected from each patient: 320 blood samples; 160 (pre-catheterized) and the other 160 (postcatheterization), 160 catheter tips and 160 swabs. The clinical samples were cultured on ordinary media for isolation and identification of the isolated microorganisms. Antibiotic sensitivity was determined by disk diffusion method according to National Committee of Clinical Laboratory Standard 2007 (NCCLS). Microscan automated system was also used for both identification and antimicrobial sensitivity testing. Statistical analysis used SPSS-10 version statistical software. One hundred forty two out of 160 patients (88.75%) suffered from CRIs. Catheter related infections were categorized according to CDC guidelines into Catheter-Related Blood Stream Infection (CR-BSI), Clinical Blood Stream Infection (C-BSI), Bloodstream Infection (BSI), Catheter bacteremia (CB) and Exit Site Infection (ESI), their rates were 23.2%, 8.5%, 47.9%, 2.8 % and 0.7% respectively and 16.9% were mixed infections. Semiquantitative culture was used for CRIs diagnosis. The total number of pathogens was 293 microorganisms were isolated from 261 positive cultures. Out of them 139 (47.4%) were Gram positive bacteria, 136 (46.4%) were Gram negative bacteria and 18 (6.1%) were Fungi. High frequency of microorganisms were isolated from post catheterization blood specimens (80.63%) followed by catheter tip samples (44.3%), swabs (29.4%) and the pre-catheterization blood specimens showed the lowest frequency of isolated microorganisms (6.88%).The isolated microorganisms identified by conventional and semiquantitative methods were belonging to 17 different species. The main etiological Gram positive bacteria was Coagulase negative Staphylococci (CoNS) representing (30.8%) and the main etiological Gram negative bacteria was Klebsiella pneumonia representing (10.6%). Pathogens isolated from CR-BSI were 42 isolates belonging to 13 different species; the most prevalent isolate was CoNS representing (42.9%). Pathogens isolated from C-BSI were 12 isolates belonging to 6 different species, the most prevalent isolate was S. aureus representing (41.7%) while 83 pathogens were isolated from BSI and they were belonging to 14 different species, the most prevalent isolates were CoNS representing (38.6%). Pseudomonas aeruginosa was the microorganism isolated from the single ESI detected in the study. The isolated pathogens from CRIs showed a wide range of antibiotic resistance. The emergence of multi-resistant pathogens in ICUs was highly detected in the present study. The most Gram positive and Gram negative bacteria causing CRIs were sensitive to imipenem and vancomycin. Proper insertion and care of catheters are essential to avoid infection. Education and training of health professionals on the practice of dealing with the CVC is an important tool in preventing and reducing CRIs.