Risk factors and outcomes of patients with metallo-beta-lactamase-producing gram-negative bloodstream bacterial infections in ICU: a prospective observational study.

Phenotypic detection of MBLs (e.g., combined disk tests with EDTA) is routinely available in many labs but it is not a molecular diagnostic method. Molecular assays (PCR for common bla genes) like BCID 2 (BioFire Blood Culture Identification 2) provide faster, gene specific identification and are now widely used in clinical settings.

Our prospective observational study will enrol 600 patients with BCID 2 confirmed carbapenemase producing blood stream infection after obtaining informed consent. Current antibiotic use and its duration will not affect enrolment decision. The study will be limited to gram negative bacterial infections by Acinetobacter baumanii complex, Pseudomonas aeruginosa, and Enterobacterales (Klebsiella spp. & E. coli only).

 All carbapenemase producing study bacteria will be grouped in to MBL producers and MBL non producers.  Predefined risk factors in both the groups will be studied along with 28-day all-cause mortality and ICU length of stay (ICU LOS). Incidence of MBL GNB in BCID 2 samples will also be calculated.

 This study might help to find the current incidence of blood stream gram-negative infections with MBL’s, associated patient risk factors and mortality in the setting of a tertiary care ICU. This will help to frame empiric antibiotic policy in the ICU patients in the presence of studied risk factors.