title: Coexistence of multiple PCR-ribotype strains of Clostridium difficile in faecal samples limits epidemiological studies.
abstract: Clostridium difficile is an important cause of antibiotic-associated diarrhoea. The simultaneous presence of different strains in individual faecal samples has not yet been established, but is important for epidemiological studies. Recurrences of Clostridium difficile-associated diarrhoea (CDAD) are observed in 15-20 % of patients and have been reported as relapses or reinfections with a new strain. In a period of 1 year, 28 faecal samples from 23 patients with a first episode of CDAD were collected at the Leiden University Medical Centre. In addition, 52 faecal samples from 23 patients, from three different hospitals, with one (n = 19), two (n = 2) or three (n = 2) recurrences were studied. PCR-ribotyping was applied as the standard typing method for the isolates. The toxinogenic and clindamycin-resistance profiles of the isolates was determined by PCR. Of 23 patients with a first episode of CDAD, two (8.7 %) harboured two different types, with no differences in toxinogenicity or clindamycin resistance, within one faecal sample. One of these 23 patients showed two types in three faecal samples from the same episode. Of the 23 patients with recurrences, six (26 %) showed a different strain type isolated in a recurrent episode. The number of cases of multiple C. difficile strains in faecal samples from patients with a first episode of CDAD did not differ significantly from the number of different strains present in recurrent episodes (chi-square test, P < or = 0.2). This observation limits the application of typing methods for studying the epidemiology of CDAD.
authors.affiliation: Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands 2Department of Medical Microbiology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Renate J
authors.initials: RJ
authors.lastname: van den Berg
authors.affiliation: Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands 2Department of Medical Microbiology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Hadi Aa
authors.initials: HA
authors.lastname: Ameen
authors.affiliation: Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands 2Department of Medical Microbiology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Furusawa
authors.affiliation: Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands 2Department of Medical Microbiology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Eric Cj
authors.initials: EC
authors.lastname: Claas
authors.affiliation: Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands 2Department of Medical Microbiology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Eric R
authors.initials: ER
authors.lastname: van der Vorm
authors.affiliation: Department of Medical Microbiology, Centre for Infectious Diseases, Leiden University Medical Centre, Leiden, The Netherlands 2Department of Medical Microbiology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Ed J
authors.initials: EJ
authors.lastname: Kuijper
mesh_terms: D001427:Bacterial Toxins / Q000235:genetics; D015373:Bacterial Typing Techniques; D016360:Clostridioides difficile / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D003015:Clostridium Infections / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology*; D005243:Feces / Q000382:microbiology*; D006801:Humans; D016133:Polymerase Chain Reaction; D021521:Ribotyping
chemical_list: D001427:Bacterial Toxins