Gut colonization, acquisition, and persistence of β-lactamase-producing Enterobacterales among hospitalized patients in Addis Ababa, Ethiopia.

backgroundInfection with Extended-Spectrum Beta-Lactamase-producing Enterobacterales (ESBL-PE) is of great global health concern and even in the absence of infections, colonization is a great threat as it can lead to cross-transmission or translocation of ESBL-PE resulting to multidrug resistance infections. Therefore, it is crucial to determine the fecal carriage of ESBL-PE to mitigate the risk of subsequent infections.

objectiveThis study determined the colonization, acquisition, and persistence of ESBL-PE and β-lactamase genes and associated factors among hospitalized patients on admission and during their hospital stay.

methodsLongitudinal cohort study was conducted among hospitalized patients from February 2023 to April 2024 at Tikur Anbessa Specialized Hospital, in Addis Ababa, Ethiopia. Fecal samples were collected and processed using standard microbiological techniques. VITEK 2 compact system was used for microbial identification, Antibiotic Susceptibility Testing (AST), and testing ESBL production. The presence of β-lactamase genes was determined using Polymerase Chain Reaction (PCR).

resultThe overall prevalence of fecal colonization with ESBL-PE among hospitalized patients was 64.8% (95%CI = 56.9–72.0). At admission, ESBL-PE fecal carriage was 44.2% (73/165). The prevalence significantly increased to 63.0% (104/165; P < 0.001) after 14 days hospitalization, by phenotypic method. A total of 177 ESBL-PE was detected during both at admission and after 14 days of hospitalization from the admitted patients, where E. coli accounted for 77.9% (138/177) followed by K. pneumoniae, which accounted for 22.0%, (39/177). The prevalence of β-lactamase genes for at least one gene was 43.0% (71/165) at admission and 62.4% (103/165; P < 0.001) after 14 days of hospitalization. The most frequently identified gene upon admission was blaCTX−M with a detection rate of 63.0%, followed by blaSHV at 41.2%, and blaTEM at 35.6%. During the 14 days of hospitalization, the frequency of blaCTX−M, blaTEM and blaSHV were found to be 70.2%, 54.8%, and 42.3%, respectively. Patients with a history of ICU admission (aOR = 5.19, 95%CI = 1.42–18.88, P = 0.020) and previous antibiotic exposure (aOR = 2.15, 95%CI = 1.12–4.92, P = 0.012) were significantly associated with ESBL-PE colonization.

conclusionHospitalized patients had high fecal carriage of ESBL-PE, with the blaCTX−M β-lactamase gene being the most frequently identified. Previous antibiotic treatment, admission to the ICU, and ongoing antibiotic treatments were associated with ESBL-PE colonization. These findings underscore the necessity of screening patients for fecal carriage of ESBL-PE upon admission and during their hospital stay. This approach is essential for the early identification of potential carriers and the implementation of infection prevention and control measures in the hospital. CLINICAL TRIAL NUMBER: Not applicable.