Clinical and microbiologic characteristics of tcdA-negative variant clostridium difficile infections

BACKGROUND: The tcdA-negative variant (A(-)B(+)) of Clostridium difficile is prevalent in East Asian countries. However, the risk factors and clinical characteristics of A(-)B(+)C. difficile infections (CDI) are not clearly documented. The objective of this study was to investigate these characteristics. METHODS: From September 2008 through January 2010, the clinical characteristics, medication history and treatment outcomes of CDI patients were recorded prospectively. Toxin characterization and antibiotic susceptibility tests were performed on stool isolates of C. difficile. RESULTS: During the study period, we identified 22 cases of CDI caused by tcdA-negative tcdB-positive (A(-)B(+)) strains and 105 cases caused by tcdA-positive tcdB-positive (A(+)B(+)) strains. There was no significant difference in disease severity or clinical characteristics between the two groups. Previous use of clindamycin and young age were identified as significant risk factors for the acquisition of A(-)B(+) CDI (OR = 4.738, 95% CI 1.48–15.157, p = 0.009 and OR = 0.966, 95% CI 0.935–0.998, p = 0.038, respectively) in logistic regression. Rates of resistance to clindamycin were 100% and 69.6% in the A(-)B(+) and A(+)B(+) isolates, respectively (p = 0.006), and the ermB gene was identified in 17 of 21 A(-)B(+) isolates (81%). Resistance to moxifloxacin was also more frequent in the A(-)B(+) than in the A(+)B(+) isolates (95.2% vs. 63.7%, p = 0.004). CONCLUSIONS: The clinical course of A(-)B(+) CDI is not different from that of A(+)B(+) CDI. Clindamycin use is a significant risk factor for the acquisition of tcdA-negative variant strains

Epidemiology and Clinical Characteristics of Clostridium difficile Infection in a Korean Tertiary Hospital

In order to investigate the incidence, clinical and microbiologic characteristics of Clostridium difficile infection (CDI) in Korea, a prospective observational study was performed. From September 2008 through January 2010, all patients whose stool was tested for toxin assay A&B and/or C. difficile culture were studied for clinical characteristics. Toxin types of the isolates from stool were tested. The mean incidence of CDI per 100,000 patient-days was 71.6 by month (range, 52.5-114.0), and the ratio of CDI to antibiotic-associated diarrhea was 0.23. Among 200 CDI patients, 37.5% (75/200) was severe CDI based on severity score. Clinical outcome of 189 CDI was as followed; 25.9% (49/189) improved without treatment, 84.3% (118/140) achieved clinical cure and attributed mortality was 0.7% (1/140) with the treatment. Recurrence rate was 21.4% (30/140) and cure without recurrence was 66.4% (93/140). The most common type of toxin was toxin A-positive/toxin B-positive strain (77.5%), toxin A-negative/toxin B-positive strains or binary toxin-producing strains comprised 15.4% or 7.1%, respectively. In conclusion, the incidence of CDI in Korea is a little higher than other reports during the non-epidemic setting. We expect that the change of epidemiology and clinical severity in CDI can be evaluated based on these results

Diversity of binary toxin positive Clostridioides difficile in Korea

Abstract The objective of this study is to determine the trend and diversity of binary toxin-positive Clostridioides difficile over 10 years in Korea. Binary toxin-positive strains were selected from a tertiary hospital in Korea in 2009–2018. The multi-locus sequence typing and antibiotic susceptibility test were performed. Among the 3278 isolates in 2009–2018, 58 possessed binary toxin genes (1.7%). The proportion of CDT- positive isolates was 0.51–4.82% in 2009–2018, which increased over the 10-year period (P = 0.023). Thirteen sequence types (STs) were identified; ST5 (14 [24%]), ST11 (11 [19%]), ST221 (10 [17%]), ST201 (7 [12%]) and ST1 (5 [9%]) were popular. All 58 isolates were susceptible to vancomycin and piperacillin/tazobactam, and clindamycin and moxifloxacin were active in 69.0% and 62% of isolates, respectively. ST1 strains were resistant to several antibiotics, including moxifloxacin (80%), clindamycin (60%) and rifaximin (60%). Moreover, four of five ST1 presented a metronidazole minimum inhibitory concentration of 4 µg/mL. Moxifloxacin resistance was highest (72.3%) for ST11. In conclusion, binary toxin-positive strains are non-prevalent in Korea and involve diverse STs. ST1 strains were resistant to several antibiotics

Clinical Characteristics and Treatment Outcomes of Clostridium difficile Infections by PCR Ribotype 017 and 018 Strains.

The objective of this study was to identify the clinical characteristics of Clostridium difficile infections (CDIs) caused by toxin A-negative/toxin B-positive (A-B+) PCR ribotype 017 (R017) and A+B+ ribotype 018 (R018) strains, prevalent in Asian countries. From February 2010 through January 2013, all CDI patients in our hospital were enrolled; their medical records were retrospectively reviewed, and the isolates were characterized by toxigenic culture and PCR ribotyping. Based on the ribotypes, a total of 510 cases were categorized as R017 (139, 27.3%), R018 (157, 30.8%) and other ribotypes groups (214, 42.0%), and clinical variables were compared between R017 and other ribotypes, R018 and other ribotypes and R018 and R017 groups. The patients with R017 infections had a higher mean Charlson's comorbidity index (OR 1.1, 1-1.21, p = 0.05), lower serum albumin (OR 0.47, 0.31-0.73, p = 0.001) and lower CRP levels (OR 0.96, 0.92-0.99, p = 0.022) than those with other ribotypes. R018 infections caused more azotemia (OR 4.06, 1.28-12.91, p = 0.018) and more frequent severe CDI (OR 1.87, 1.12-3.13, p = 0.016) than the other ribotypes infections. R017 and R018 infections were more often associated with toxin positive stools (OR 2.94, 1.65-4.09, p<0.001; OR 4.55, 2.82-7.33, p<0.001). In terms of treatment outcomes, R017 infections caused a marginally higher 30-day mortality than other ribotypes infection. In a final multiple logistic regression model, 30-day mortality was associated with leukocytosis (OR 2.45, 1.0-6.01, p = 0.05) and hypoalbuminemia (OR 4.57, 1.83-11.39, p = 0.001), but only marginally with R017 infection (OR 2.14, 0.88-5.22, p = 0.094). In conclusion, infections by C. difficile R018 strains tend to cause more severe disease, while there was a trend for higher mortality with R017 infections

Association of QnrB Determinants and Production of Extended-Spectrum β-Lactamases or Plasmid-Mediated AmpC β-Lactamases in Clinical Isolates of Klebsiella pneumoniae

Clinical isolates of Escherichia coli and Klebsiella pneumoniae producing extended-spectrum β-lactamases or plasmid-mediated AmpC β-lactamases were screened for qnrA and qnrB genes. QnrB was present in 54 of 54 DHA-1-producing K. pneumoniae isolates and 10 of 45 SHV-12-producing ones, suggesting that the distribution of plasmids conferring resistance to extended-spectrum cephalosporins and quinolones in clinical isolates of K. pneumoniae is widespread

Appropriate duration of peripherally inserted central catheter maintenance to prevent central line-associated bloodstream infection.

Background/aimProlonged maintenance of central venous catheters, including peripherally inserted central catheters (PICCs), is a major risk factor for central line-associated bloodstream infection (CLABSI). This study was conducted to evaluate the appropriate duration of PICC maintenance to prevent CLABSI.MethodsA single-center retrospective study was conducted at an 824-bed tertiary hospital in Korea between January 2010 and December 2017. All hospitalized patients who underwent ultrasound-guided PICC insertion were enrolled. CLABSI was diagnosed according to the definitions of the National Health Safety Network. CLABSI caused by PICC was defined as PICC-associated bloodstream infection (PABSI). To identifying statistical correlations between catheter days and PABSI, the odds ratio for PABSI on the basis of the continuous value of catheter days was analyzed using restricted cubic spline splits with five knots. The optimal cut-off value for catheter days was identified by maximizing the area under the receiver operating characteristic (ROC) curve (AUC).ResultsA total of 1,053 patients underwent ultrasound-guided PICC insertion during the study period. Among them, 36 were confirmed as having a PABSI (3.5%, 36/1014; 1.14 per 1000 catheter days). In the restricted cubic spline regression, catheter days showed a dose-dependent relationship with the risk of PABSI. The AUC of the ROC curve for developing a PABSI according to the duration of catheter maintenance was 0.715 (95% CI, 0.639-0.790); the calculated optimal cut-off value was 25 days.ConclusionThe incidence of PABSI was 1.14 per 1000 catheter days and the optimal cut-off value of catheter days to avoid a PABSI was 25 days

Clinical and microbiologic characteristics of <it>tcdA</it>-negative variant <it>clostridium difficile</it> infections

Abstract Background The tcdA-negative variant (A-B+) of Clostridium difficile is prevalent in East Asian countries. However, the risk factors and clinical characteristics of A-B+C. difficile infections (CDI) are not clearly documented. The objective of this study was to investigate these characteristics. Methods From September 2008 through January 2010, the clinical characteristics, medication history and treatment outcomes of CDI patients were recorded prospectively. Toxin characterization and antibiotic susceptibility tests were performed on stool isolates of C. difficile. Results During the study period, we identified 22 cases of CDI caused by tcdA-negative tcdB-positive (A-B+) strains and 105 cases caused by tcdA-positive tcdB-positive (A+B+) strains. There was no significant difference in disease severity or clinical characteristics between the two groups. Previous use of clindamycin and young age were identified as significant risk factors for the acquisition of A-B+ CDI (OR = 4.738, 95% CI 1.48–15.157, p = 0.009 and OR = 0.966, 95% CI 0.935–0.998, p = 0.038, respectively) in logistic regression. Rates of resistance to clindamycin were 100% and 69.6% in the A-B+ and A+B+ isolates, respectively (p = 0.006), and the ermB gene was identified in 17 of 21 A-B+ isolates (81%). Resistance to moxifloxacin was also more frequent in the A-B+ than in the A+B+ isolates (95.2% vs. 63.7%, p = 0.004). Conclusions The clinical course of A-B+ CDI is not different from that of A+B+ CDI. Clindamycin use is a significant risk factor for the acquisition of tcdA-negative variant strains.</p