Molecular Epidemiology of Clostridium difficile Infection in a Major Chinese Hospital: an Underrecognized Problem in Asia?

Abstract

Clostridium difficile infection is almost unrecognized in mainland China. We have undertaken a study in a large Chinese teaching hospital in Changsha, Hunan, China, to identify cases of C. difficile, record patient characteristics, and define the molecular epidemiology with respect to ribotype distribution and cross-infection. Between April 2009 and February 2010, we examined fecal samples from 70 hospitalized patients with diarrhea who were receiving or had received antibiotics within the previous 6 weeks. Clinical information was collected and the samples were cultured for C. difficile retrospectively. Isolates were ribotyped, and multiple-locus variable-number tandem-repeat assay (MLVA) subtyping was performed on clusters of the same ribotype. The mean age of patients from whom C. difficile was cultured was 58 years, with only 4/21 patients aged >65 years. All patients, with a single exception, had received a third-generation cephalosporin and/or a quinolone antibiotic. Twenty-one isolates of C. difficile were recovered, and seven different ribotypes were identified, the dominant types being 017 (48%), 046 (14%), and 012 (14%). We identified two clusters of cross-infection with indistinguishable isolates of ribotype 017, with evidence of spread both within and between wards. We have identified C. difficile as a possibly significant problem, with cross-infection and a distinct ribotype distribution, in a large Chinese hospital. C. difficile may be underrecognized in China, and further epidemiological studies across the country together with the introduction of routine diagnostic testing are needed to ascertain the size of this potentially significant problem.

A comparison of Clostridium difficile diagnostic methods for identification of local strains in a South African centre

“…The predominance of ribotype 017 strains in the set of isolates is similar to reports from healthcare centres in China (Hawkey et al, 2013;Huang et al, 2009), Taiwan (Chia et al, 2013), Korea (Shin et al, 2008) and Japan (Komatsu et al, 2003). There have also been smaller outbreaks of ribotype 017 strains in Canada (al-Barrak et al, 1999) and Europe (Drudy et al, 2007;Kuijper et al, 2001).…”

“…Nevertheless, in line with other investigations reported, the current study yielded a 22.0 % incidence of C. difficile, compared with a 9.2 % incidence with the sole use of ImmunoCard for Toxin A and B (Cohen et al, 2010; Rajabally et al, 2013;Sloan et al, 2008;Terhes et al, 2009). The predominance of ribotype 017 strains in the set of isolates is similar to reports from healthcare centres in China (Hawkey et al, 2013;Huang et al, 2009), Taiwan (Chia et al, 2013, Korea (Shin et al, 2008) and Japan (Komatsu et al, 2003). There have also been smaller outbreaks of ribotype 017 strains in Canada (al-Barrak et al, 1999) and Europe (Drudy et al, 2007;Kuijper et al, 2001).…”

Sequence Variation in tcdA and tcdB of Clostridium difficile: ST37 with Truncated tcdA Is a Potential Epidemic Strain in China

“…Yet, our previous study demonstrated significant genetic diversity in tcdA and tcdB, consistent with the results of toxinotyping based on the restriction fragment length polymorphism (RFLP)-PCR method (19,28). However, the simple classification of RFLP-PCR failed to explain more details about the epidemiological relevance and phylogenetic relationships between strains with different types of toxin genes, while the recently increased ST37 (RT017 [A Ϫ B ϩ ]) contribution (48%) for CDI cases and its epidemic potentiality in Asia (11,16) make it urgent to build a more finely described pattern to reveal the intrinsic epidemic characteristics. In the present study, we introduce a novel approach that is more discerning and accurate; for example, 13 ST35 and 11 ST2 strains were divided into 2 groups (A03B04 and A02B05 and A06B07 and A09B06, respectively).…”

“…Recently, a particular variant strain of C. difficile, ST37, which has been ribotyped as RT017 and produces toxin B only, has attracted increasing attention (11,12,16). This type of strain shows increased resistance to clindamycin and erythromycin, with concomitant greater risk to inpatient health (13,17,18).…”

“…Research on CDI has primarily focused on strains such as the hypervirulent PCR ribotype 027, multilocus sequence type 1 (RT027, ST1), emerging in Europe and North America, which produces two major toxins, A and B, encoded by the genes tcdA and tcdB in the pathogenicity locus (PaLoc) (4,5). In recent years, however, the epidemiology of CDI has changed dramatically, since other emerging PCR ribotypes have become prevalent (6)(7)(8)(9)(10)(11)(12)(13), and several pathogenic A-negative B-positive (A Ϫ B ϩ ) strains (which produce toxin B, but not toxin A) have appeared in Asia and Latin America (8-12, 14, 15). Hence, it has become a matter of urgency to understand the new, complex pattern of A Ϫ B ϩ C. difficile strain variants and to reveal their relationships to other epidemic genotypes.…”