title: Use of Cepheid Xpert Carba-R® for Rapid Detection of Carbapenemase-Producing Bacteria in Abdominal Septic Patients Admitted to Intensive Care Unit.
abstract: Early institution of effective antibiotic therapy and source control are pivotal to improve survival of abdominal septic patients. Xpert® Carba-R is a real time polymerase chain reaction assay for rapid detection and differentiation of five genes (blaKPC, blaVIM, blaOXA-48, blaIMP-1, blaNDM) responsible for carbapenem resistance. We performed an observational study investigating the clinical usefulness and applicability of Xpert® Carba-R to detect carbapenem resistance in abdominal septic patients admitted to intensive care unit. We compared the results of Xpert® Carba-R with standard microbiological culture. We collected a set of two rectal/stomia swabs and two swabs from abdominal drainage fluid for each patient. We included 20 patients for a total of 45 comparisons between the two methods. In our clinical setting, the overall performance of Xpert® Carba-R for detection of carbapenem resistance in the presence of genes detectable and non-detectable by the method was: sensitivity 50% (95% CI 24.6-75.3); specificity 93.1% (95% CI 77.2-99.1); positive predictive value (PPV) 80% (95% CI 44.4-97.5); negative predictive value (NPV) 77.1% (95% CI 56.9-89.6). The inter-rater agreement was 0.47 (SE 0.14; 95% CI 0.20-0.74). When considering the only 5 mechanisms of resistance detected by both methods, the overall diagnostic performance was: sensitivity 100% (95% CI 69.1-100), specificity 94.2 (95% CI 80.8-99.3), PPV 83.3 (95% CI 59.6-97.9) and NPV 100% (95% CI 89.4-100). The inter-rater agreement was 0.88 (SE 0.08; 95% CI 0.71-1). Xpert® Carba-R may be considered an additional diagnostic tool for early diagnosis of carbapenem resistance in abdominal septic patients. Clinicians should be aware of their epidemiology before its introduction in the diagnostic protocol of their intensive care units.
authors.affiliation: Department of Biopathology and Medical Biotechnologies (DIBIMED), Section of Anesthesia, Analgesia, Intensive Care and Emergency, Policlinico P. Giaccone, University of Palermo, Via del Vespro 129, 90127, Palermo, Italy.
authors.forename: Andrea
authors.identifier: http://orcid.org/0000-0003-1416-9993
authors.initials: A
authors.lastname: Cortegiani
authors.affiliation: Department of Biopathology and Medical Biotechnologies (DIBIMED), Section of Anesthesia, Analgesia, Intensive Care and Emergency, Policlinico P. Giaccone, University of Palermo, Via del Vespro 129, 90127, Palermo, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Russotto
authors.affiliation: Department of Sciences for Health Promotion and Mother-Child Care, University of Palermo, Palermo, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Graziano
authors.affiliation: Department of Sciences for Health Promotion and Mother-Child Care, University of Palermo, Palermo, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Geraci
authors.affiliation: Department of Sciences for Health Promotion and Mother-Child Care, University of Palermo, Palermo, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Saporito
authors.affiliation: Department of General Surgery, Urgency and Organ Transplantation, University of Palermo, Italy.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Cocorullo
authors.affiliation: Department of Biopathology and Medical Biotechnologies (DIBIMED), Section of Anesthesia, Analgesia, Intensive Care and Emergency, Policlinico P. Giaccone, University of Palermo, Via del Vespro 129, 90127, Palermo, Italy.
authors.forename: Santi Maurizio
authors.initials: SM
authors.lastname: Raineri
authors.affiliation: Department of Sciences for Health Promotion and Mother-Child Care, University of Palermo, Palermo, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Mammina
authors.affiliation: Department of Biopathology and Medical Biotechnologies (DIBIMED), Section of Anesthesia, Analgesia, Intensive Care and Emergency, Policlinico P. Giaccone, University of Palermo, Via del Vespro 129, 90127, Palermo, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Giarratano
mesh_terms: D000005:Abdomen / Q000382:microbiology; D000368:Aged; D001426:Bacterial Proteins / Q000378:metabolism*; D015780:Carbapenems / Q000494:pharmacology; D004269:DNA, Bacterial / Q000302:isolation & purification / Q000378:metabolism; D024881:Drug Resistance, Bacterial / Q000187:drug effects / Q000235:genetics; D004755:Enterobacteriaceae / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011933:Reagent Kits, Diagnostic; D060888:Real-Time Polymerase Chain Reaction; D012007:Rectum / Q000382:microbiology; D012680:Sensitivity and Specificity; D018805:Sepsis / Q000175:diagnosis* / Q000382:microbiology; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D015780:Carbapenems; D004269:DNA, Bacterial; D011933:Reagent Kits, Diagnostic; D001618:beta-Lactamases; C063912:carbapenemase