Pilot study of Clostridioides difficile infection (CDI) in hospitals, Italy, September to December 2022.

Background Clostridioides difficile infection (CDI) is a severe infection that needs to be monitored. This infection predominantly occurs in hospitalised patients after antimicrobial treatment, with high mortality in elderly patients.AimWe aimed at estimating the incidence of CDI in Italian hospitals over 4 months in 2022.MethodsWe estimated incidences of hospital-acquired CDI (HA-CDI), community or unknown CDI (CA/UA-CDI), recurrent CDI and overall CDI in 25 Italian hospitals, characterised C. difficile isolates using PCR ribotyping, analysed them for toxin genes and susceptibility to antimicrobials.Results Clostridioides difficile was detected in 9.7% (655/6,722) of samples from 550 patients, 18 patients died of CDI. The mean overall CDI incidence was 5.0 cases per 10,000 patient days (range: 0.7-11.9). For HA-CDI, mean incidence was 3.7 (range: 0.7-9.2), for CA/UA-CDI 0.8 (range: 0.0-3.2) and for recurrent CDI 0.5 (range: 0.0-3.4). Most patients were female (n = 295; 53.6%), aged ≥ 65 years (n = 422; 76.7%) and previously hospitalised (n = 275; 50.0%). Of the 270 culturable isolates, 267 (98.9%) had toxin A and B genes and 51 (18.9%) the binary toxin genes. Of the 55 PCR ribotypes (RTs) identified, RT 018 (n = 56; 20.7%) and RT 607 (n = 23; 8.5%) were the most common, RT 607 in the northern (p < 0.0001) and RT 018 in the central (p < 0.0001) regions of Italy. Most isolates (n = 158; 58.5%) were antimicrobial-resistant and 119 (44.1%) were multidrug-resistant (MDR).ConclusionHighly virulent and MDR C. difficile types are circulating in Italian hospitals which highlights the need of robust surveillance and stringent prevention and control measures.