Abstract
The COVID-19 pandemic introduced substantial changes to clinical practice, including widespread antibiotic use. These changes raised concerns about a potential rise in healthcare-associated infections, particularly Clostri dioi des difficile infection (CDI). This study aimed to investigate the hidden impact of COVID-19 treatment strategies on the incidence of CDI, with a specific focus on antibiotic use, advanced age, comorbidities, and the administration of proton pump inhibitors (PPIs) and corticosteroids. A retrospective observational study was conducted using anonymised patient data from the University Clinical Hospital Mostar. The number of CDI cases significantly increased during the COVID-19 peak in 2021, showing a perfect positive correlation with COVID-19 incidence (ρ = 1.0, p < 0.05). Antibiotic use was strongly associated with CDI (69 % vs. 12 %; p < 0.05), as was advanced age (≥ 65 years; 71 %; p < 0.05). The combined use of proton pump inhibitors and corticosteroids was significantly more frequent in the CDI group (54 % vs. 24 %; p < 0.05). The findings highlight how COVID-19 treatment strategies can unintentionally raise CDI risk, stressing the need for prudent antibiotic use, careful drug management and targeted prevention for elderly and high-risk patients.