gms | German Medical Science

Objective: To analyze the incidence and dynamic of Clostridium difficile-associated diarrhea (CDAD) and identify similarities in biotypes of isolated microorganisms.

Methods: Production of A and B toxins by C. difficile in feces was analysed with ELISA (MINI-VIDAS, Biomerrieux, France) in 385 cancer patients with suspected antibiotic -associated diarrhea, hospitalized to Cancer Research Center from January 2011 to October 2013. To identify related and epidemiological significant C. difficile in October 2013 we initiated cultivation of C. difficile from toxin-positive stool samples. 10 toxin-positive stool samples were cultured on Columbia agar supplemented with a selective mixture of cycloserine, cefoxitin and amphotericin B and incubated anaerobically using the jars and AnaeroGen system (Oxoid, England) at 37°C for 48 h. Identification was performed using the Bruker Biotyper MALDI-TOF MS platform by spotting whole cells directly from culture medium onto target plates. Data were processed with FlexControl, version 3.0 software.

Results: A total of 548 analysis of feces for C. difficile toxin A and B production was performed. The level of toxins was 0.47-9.4. Annual increase in the number of samples for C. difficile toxins production from 48 samples (from 45 patients) in 2011 to 147 samples (from 104 patients) in 2012 and 352 samples (from 236 patients ) in 2013 (ten months). A total of 89 patients had positive C. difficile toxins A and B. Number of patients with positive results was 7/45 (15.6%) in 2011, 24/104 (23.1%) in 2012 and 57/ 236 (24.2%) in 2013. Among 89 patients with CDAD patients from 20 clinical departments were registered, with prevalence of patients from hematology department 18 % (16 /89) during study period. Recurrent CDAD was reported in 11/89 patients (5 in 2012 and 6 in 2013). 10 toxin-positive stool samples were cultivated and 9 C. difficile were isolated. All C. difficile isolates were identified to the species level with a score above 2.0 and belonged to type strain MB_4499_05 THL, which indicates their clonality.

Conclusion: The increase in the number of tests for C. difficile toxin may be related to the increased number of CDAD and with the efficiency and speed of diagnosis by detecting toxins that caused a growing interest in this type of diagnosis in 2012 and 2013 compared with 2011. All isolates of C. difficile belonged to one clone.