MDR Bacteremia in the Critically Ill During COVID-19: The MARTINI Study

Multidrug-resistant (MDR) bloodstream infections (BSIs) constitute a major challenge in intensive care units, with the COVID-19 pandemic compromising infection control and potentially increasing MDR incidence. Comparative data between COVID and non-COVID ICU populations remain limited. The MARTINI study is a retrospective observational analysis held in a tertiary hospital during the COVID-19 pandemic (2020-2022) encompassing adult patients with MDR BSIs admitted to COVID and non-COVID ICUs. Demographics, comorbidities, severity scores, microbiology, resistance patterns, and outcomes were accessed and compared. A binary logistic regression model and multivariate regression was performed to identify independent predictors of ICU mortality. Among the study's 156 patients (106 COVID-ICU, 50 non-COVID-ICU), COVID-ICU patients were significantly older with higher comorbidity and severity scores. Gram-negative pathogens predominated in both cohorts, mainly <i>Acinetobacter baumannii</i> and <i>Klebsiella pneumoniae</i>, with comparable resistance mechanisms. Timing of bacteremia onset and initiation of appropriate therapy did not differ between groups. However, ICU mortality was markedly higher in COVID-ICU patients (74.5% vs. 38%, <i>p</i> < 0.001). Age, SOFA score, the presence of systemic inflammation (SIRS) and COVID-19 infection were identified as independent predictors of mortality. Although pathogen distribution and resistance were similar across groups, COVID-ICU patients experienced significantly poorer outcomes. Strengthened infection control and timely and targeted antimicrobial therapy are essential to diminish MDR bacteremia risk in critically ill populations.