Occurrence of Clostridium difficile infections in Serbia and high proportion of PCR ribotype 027 strains in two hospitals in Belgrade

Background: The incidence of Clostridium difficile infections (CDI) in the Clinical Center of Serbia (CCS) and the entire Serbia has been constantly rising in the previous 5 years. We aimed to study C. difficile PCR-ribotypes isolated from patients hospitalized at two healthcare institutions: CCS and Specialized Hospital for Cerebrovascular Diseases "Sveti Sava" (SS), both of them from Belgrade, and to investigate the incidence rates of CDI in hospital settings in Serbia, from 2009 to 2013.

Methods: The Bacteriology laboratory database at Clinic for Infectious and Tropical Diseases of CCS was queried from January 1, 2009 to December 31, 2013 for all patients who underwent immunochromatographic toxin A and/or toxin B stool testing and C. difficile stool culture for suspected infection caused by this bacterium. Toxigenic culture was not performed. Ninety- six C. difficile isolates were then selected and characterized by PCR-ribotyping. These were obtained from 94 patients hospitalized in different clinics of CCS and SS from November 2011 to December 2013.

Results: Among 6164 stool samples sent to Bacteriology laboratory for culture of C. difficile and toxin detection during the study period, 1775 (28.8%) were positive, displaying linear trend of growth. From 96 isolates, typed by PCR-ribotyping, majority (85; 88.54%) belonged to PCR-ribotype 027. The remaining 11 isolates belonged to PCR-ribotypes 014/020 (3 isolates), 015, SLO 191 (two isolates each), 017, 018, 070 and 001/072 (one isolate each).

Conclusion: Our results demonstrated that C. difficile PCR-ribotype 027 is by far predominant in two hospital settings in Belgrade, at least since 2011.