Search in the Abstract Database

* = Presenting author

P372. Preliminary results from a prospective study on Clostridium difficile prevalence, toxino type and antibiotic sensitivity in inflammatory bowel disease patients

P372. Preliminary results from a prospective study on Clostridium difficile prevalence, toxino type and antibiotic sensitivity in inflammatory bowel disease patients

M. Martinato1, A. Grillo1, R. D'Incà1, M. Scarpa2, R. Caccaro1, G.C. Sturniolo1, I. Castagliuolo1

1Università degli Studi di Padova, Padova, Italy; 2Venetian Oncologic Institute IRCCS, Padova, Italy

Background: Clostridium difficile is an opportunistic pathogen causing about 20% of all cases of antibiotic-associated diarrhoea. The importance of Clostridium difficile infection (CDI) in Inflammatory Bowel Disease (IBD) patients is increasingly being recognized and stool testing in relapsing patients is nowadays recommended by international guidelines.

Aim: The aim of the study was to describe the prevalence of Clostridium difficile infection in IBD according to clinical activity; characterize Clostridium difficile strains isolated from IBD patients as regard to antibiotic sensitivity and toxino type.

Study design: Stool samples were collected from IBD patients and age- and sex-matched healthy controls (n = 40). IBD patients in remission or with mild disease activity have been enrolled during a routine follow-up visit (n = 80), while severe patients were enrolled at hospital admission (n = 23). On each faecal sample we performed an anaerobic culture on solid media after 70% ethanol shock followed by specific 16SRNA polymerase chain reaction (PCR) to identify Clostridium difficile colonies. Positive colonies were characterized by multiplex PCR to identify microbe toxino-type. E-test was performed for ciprofloxacin, metronidazole and vancomycin sensitivity. Clinical data were collected in order to correlate CDI to antibiotics use, disease activity, disease extent and location, type of therapy (mesalazine, steroids, immunomodulators, proton pump inhibitors, probiotics) and hospitalization.

Results: In healthy controls CDI prevalence was 10%, however all the identified strains were non toxigenic and therefore non pathogenic.

In IBD patients in remission, Clostridium difficile was identified in 16.3% but only 15.4% of the strains were toxigenic) whereas in patients with active disease the incidence of Clostridium difficile was 13% with 33% of the strains being toxigenic.

All toxigenic Clostridium difficile strains isolated from IBD patients with active disease were toxin A and toxin B positive (A+; B+), whereas among patients in remission 50% were A+B+ and 50% A−B+.

Clostridium difficile strains isolated from IBD patients with active disease were resistant to Ciprofloxacin (MIC > 32 mg/L), but susceptible to Metronidazole (MIC < 0.19–0.75 mg/L) and Vancomycin (MIC < 0.5 mg/L).

Multivariate analysis identified patients with ileal Crohn's disease (CD) and patients treated with biologics as the groups at higher risk of Clostridium difficile colonization.

Conclusion: IBD patients are at higher risk of CDI and Clostridium difficile colonization with respect to controls. Clostridium difficile colonization is more frequent in ileal CD and in patients treated with biologics.

CDI is more frequent in severe hospitalized patients. Immunoassays, routinely used in clinical practice, should test both toxin A and toxin B. Ciprofloxacin should not be used for treating CDI.