Perez-Nadales, ElenaM Natera, AlejandraRecio-Rufian, ManuelGuzman-Puche, JuliaMarin-Sanz, Juan AntonioMartin-Perez, CarlosCano, AngelaCaston, Juan JoseElias-Lopez, CristinaMachuca, IsabelGutierrez-Gutierrez, BelenMartinez-Martinez, LuisTorre-Cisneros, Julian2023-05-032023-05-032022-05-20Pérez-Nadales E, M Natera A, Recio-Rufián M, Guzmán-Puche J, Marín-Sanz JA, Martín-Pérez C, et al. Prognostic Significance of the Relative Load of KPC-Producing Klebsiella pneumoniae within the Intestinal Microbiota in a Prospective Cohort of Colonized Patients. Microbiol Spectr. 2022 Aug 31;10(4):e0272821http://hdl.handle.net/10668/20045Increased relative bacterial load of KPC-producing Klebsiella pneumoniae (KPC-KP) within the intestinal microbiota has been associated with KPC-KP bacteremia. Prospective observational study of KPC-KP adult carriers with a hospital admission at recruitment or within the three prior months (January 2018 to February 2019). A qPCR-based assay was developed to measure the relative load of KPC-KP in rectal swabs (RLKPC, proportion of blaKPC relative to 16S rRNA gene copy number). We generated Fine-Gray competing risk and Cox regression models for survival analysis of all-site KPC-KP infection and all-cause mortality, respectively, at 90 and 30 days. The median RLKPC at baseline among 80 KPC-KP adult carriers was 0.28% (range 0.001% to 2.70%). Giannella Risk Score (GRS) was independently associated with 90-day and 30-day all-site infection (adjusted subdistribution hazard ratio [aHR] 1.23, 95% CI = 1.15 to 1.32, P 7, aHR 2.96, 95% CI = 0.97 to 9.07, P = 0.057). KPC-KP relative intestinal load was independently associated with all-cause mortality in our clinical setting, after adjusting for age and severe KPC-KP infection. Our study confirms the utility of GRS to predict infection risk in patients colonized by KPC-KP. IMPORTANCE The rapid dissemination of carbapenemase-producing Enterobacterales represents a global public health threat. Increased relative load of KPC-producing Klebsiella pneumoniae (KPC-KP) within the intestinal microbiota has been associated with an increased risk of bloodstream infection by KPC-KP. We developed a qPCR assay for quantification of the relative KPC-KP intestinal load (RLKPC) in 80 colonized patients and examined its association with subsequent all-site KPC-KP infection and all-cause mortality within 90 days. Giannella Risk Score, which predicts infection risk in colonized patients, was independently associated with the development of all-site KPC-KP infection. RLKPC was not associated with all-site KPC-KP infection, possibly reflecting the large heterogeneity in patient clinical conditions and infection types. RLKPC was an independent predictor of all-cause mortality within 90 and 30 days in our clinical setting. We hypothesize that KPC-KP load may behave as a surrogate marker for the severity of the patient's clinical condition.enKPC-producing Klebsiella pneumoniaeBacterial loadInfectionIntestinal colonizationMortalityÁrea de Gestión Sanitaria Nordeste de GranadaAdultAnti-bacterial agentsBacterial proteinsGastrointestinal microbiomeHumansKlebsiella infectionsKlebsiella pneumoniaePrognosisProspective studiesRNA, ribosomal, 16Sbeta-Lactamasesresearch article35766500open accessARN ribosómico 16SAntibacterianosInfecciones por KlebsiellaMicrobioma gastrointestinalPronósticoProteínas bacterianas10.1128/spectrum.02728-212165-0497PMC9431423https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9431423https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9431423/pdf