Factores asociados a infección por Bacilos Gram-Negativos Resistentes a Carbapenémicos en pacientes hospitalizados en un Hospital General de Agudos

Abstract

Objectives: To determine the factors associated with infection by carbapenem resistant Gram-negative bacilli (CRGNB-I) and its morbidity and mortality.

Materials and methods: Retrospective, observational, descriptive, and comparative study of episodes of CRGNB-I inpatients at Hospital Lagomaggiore, Mendoza. Period: 9/2023–9/2024. CR-GNB-I: isolation of such pathogens in clinically significant cultures.

Results: CRGNB-I: 19 cases, 13 (68.5%) female, mean age 44.6 ±11.1 years. Admitted to Internal Medicine: 7 (36.8%). Comorbidities: DM 6 (31.6%), BMI ≥25 kg/m² 5 (26.3%), oncohematologic and HTN 4 (21%). Prior hospitalization in last 3 months: 8 (42.1%), prior surgery (in last 6 months) 8 (42.1%): abdominal in 5 (62.5%). Hospital stay >7 days: 19 (100%); PPI use: 15 (78.9%); patient/nurse ratio >3:1 in 14 (73.7%); hypoalbuminemia: 11 (57.9%); NG tube: 11 (57.9%); OTI: 8 (42.1%); hypoproteinemia: 7 (36.8%); carbapenem use in previous month: 7 (36.8%); immunosuppressants: 6 (31.6%). More than 5 risk factors: 15 (78.95%). Prior colonization: 12 (63.2%). Isolates: Klebsiella pneumoniae in 9 (47.7%). Resistance mechanisms: enzymatic in 11 (57.9%)—New Delhi metallo-β-lactamase (NDM) in 9 (81.8%), Klebsiella pneumoniae carbapenemase (KPC) in 2 (18.1%). Within the MBL group: New Delhi metallo-β-lactamase (NDM) 7 (77.8%), Verona integron-encoded metallo-β-lactamase (VIM) 1 (11.1%), and could not be categorized due to lack of availability of molecular methods 1 (11.1%); non-enzymatic in 8 (42.1%). Positive cultures: urine 6 (31.6%), bacteremia 3 (15.8%). Sepsis in 11 (57.9%), septic shock 9 (47.8%), and death 3 (15.8%). Inadequate empirical antibiotic therapy (IEAT): 10 (52.6%). Comparing ≥5 CR-GNB-I risk factors vs <5: ICU transfer 12 (80%) vs 0, p=0.003; sepsis 11 (73.3%) vs 0, p=0.008; septic shock 9 (60%)vs0,p=0.03.

Conclusions: In our series, CRGNB-I occurred mostly in women, with a urinary source. Klebsiella pneumoniae was the most frequently isolated organism. The most common resistance mechanism was enzymatic (NDM type). Prior colonization was a relevant risk factor. The presence of ≥5 risk factors was associated with complications such as sepsis and death.