Interprofessional Antimicrobial Stewardship Influencing Clostridioides difficile Infection: An 8-Year Study Using Antimicrobial Use Density.

PURPOSE: To reduce Clostridioides difficile infection (CDI), we implemented interprofessional antimicrobial, infection control, and diagnostic stewardship (ipAS) conducted by physicians/pharmacists, infection control nurses, and medical technologists, respectively. As a numerical indicator for ipAS, we used antimicrobial use density (AUD) in an 8-year study to validate its efficacy in CDI reduction. PATIENTS AND METHODS: This was an observational study. CDI was defined as stool samples or C. difficile isolates containing toxin A and/or B from a patient with diarrhea occurring three or more times per day. From 2011-2018 at a 10-ward single site the subjects were in-patients with CDI, and the following data were collected: AUDs for 23 antibiotics, and antimicrobial test results. By 2015, we had established ipAS, consisting of culture submission before the administration of broad-spectrum antimicrobials, the promotion of point-of-care testing for diagnosis-based antimicrobials, perioperative prophylactic antibiotics, intervention at positive diagnosis of blood culture, team round for diarrhea, and inspection on contact precautions and disinfection in CDI cases. The study outcomes included annual numbers of CDI patients and blood culture sets. We compared annual AUDs between former (2011-14) and latter (2015-18) periods using Kruskal-Wallis tests and examined the correlation between AUDs and CDI numbers. RESULTS: Of a total 50,970 patients, 1,750 patients underwent C. difficile toxin tests, of whom 171 patients (9.8%) were positive for CDI. Between the former and latter periods, AUDs for flomoxef (11.96 to 2.71 by medians), panipenem/betamipron (0.30 to 0.00), and clindamycin (3.87 to 2.19) significantly decreased (P<0.05) as did numbers of CDIs (26.5 to 10) (P=0.043). The correlation analysis revealed a significant correlation between AUD for flomoxef and CDIs (P=0.004) and the AUD for piperacillin/tazobactam and CDIs (P=0.010) with a positive Pearson r. CONCLUSION: The integrated antimicrobial, diagnostic, and infection control approach used in ipAS may reduce CDIs.

Does antimicrobial use density at the ward level influence monthly central line-associated bloodstream infection rates?

The aim of this study was to elucidate risk factors, including ward antimicrobial use density (AUD), for central line-associated bloodstream infection (CLABSI) as defined by the Centers for Disease Control and Prevention in a 430-bed community hospital using central venous lines with closed-hub systems. We calculated AUD as (total dose)/(defined daily dose × patient days) ×1,000 for a total of 20 drugs, nine wards, and 24 months. Into each line day data, we inputed AUD and device utilization ratios, number of central line days, and CLABSI. The ratio of susceptible strains in isolates were subjected to correlation analysis with AUD. Of a total of 9,997 line days over 24 months, CLABSI was present in 33 cases (3.3 ‰), 14 (42.4%) of which were on surgical wards out of nine wards. Of a total of 43 strains isolated, eight (18.6%) were methicillin-resistant Staphylococcus aureus (MRSA); none of the MRSA-positive patients had received cefotiam before the onset of infection. Receiver-operating characteristic analysis showed that central line day 7 had the highest accuracy. Logistic regression analysis showed the central line day showed an odds ratio of 5.511 with a 95% confidence interval of 1.936-15.690 as did AUD of cefotiam showing an odds ratio of 0.220 with 95% confidence interval of 0.00527-0.922 (P=0.038). Susceptible strains ratio and AUD showed a negative correlation (R (2)=0.1897). Thus, CLABSI could be prevented by making the number of central line days as short as possible. The preventative role of AUD remains to be investigated.

Is Clostridium difficile infection influenced by antimicrobial use density in wards?

This study was performed to elucidate the relationship between antimicrobial use density (AUD) and Clostridium difficile infection (CDI) manifesting as antimicrobial-associated diarrhea (AAD) in hospital wards during a 4-year period. Case definition of CDI was an adult exhibiting AAD with a daily stool frequency of three or more, arising at least 48 hours after ward admission, and fecal samples testing positive for toxin (A and/or B). Metronidazole or vancomycin was orally administered as treatment. AUDs were calculated for a total of 21 antimicrobials in a span of 48 months and nine wards. We included the average value of AUDs, representing two succeeding months of sample submission into the sample information. We also entered data on the 2-year division and intensified contact precaution for statistical analysis. Of a total of 463 cases, 95 (20.5%) were CDI-positive. Multivariate regression analysis showed odds ratios [OR] of 1.739 (95% confidence interval [CI] of 1.050 - 2.881, P = 0.032) and 1.598 (95% CI of 1.006 -2.539, P = 0.047) for clindamycin and piperacillin, respectively in AUD. Thus increased ward AUDs of clindamycin and piperacillin may run the risk of CDI.

Association between risk of bloodstream infection and duration of use of totally implantable access ports and central lines: a 24-month study.

BACKGROUND: Prolonged use of totally implantable access ports (APs) and central lines (CLs) has been known to carry a risk of bloodstream infection (BSI), but the safe cutoff day for discontinuing use remains unknown. We performed a receiver operating characteristic (ROC) curve analysis to determine this cutoff. METHODS: A retrospective 24-month study covered a total of 22,481 days of device use. For each day of use, the following findings were recorded: patient age and sex; presence or absence of diabetes mellitus, preexisting sepsis, and renal disease; and occurrence of device-associated BSI. BSI was defined in accordance with the Centers for Disease Control and Prevention's definition of catheter-related infection. RESULTS: BSIs occurred in 81 patients with an AP, for a BSI rate of 2.81 cases per 1,000 days of use. Among the 896 patients with a CL, the BSI rate was 5.60 cases per 1,000 days of use. The ROC analysis found a cutoff time of 33 days for APs (median days of use, 48) and 10 days for CLs (median days of use, 20.5). For the total 22,481 days of use, the odds ratio between APs and CLs with respect to BSI was 0.556 (95% confidence interval [CI], 0.256-1.208; P = .138). Days of use beyond the cutoff had an odds ratio of 2.867 (95% CI, 1.823-4.507; P < .001). Among the risk factors, preexisting sepsis had an odds ratio of 7.843 (95% CI, 4.666-13.184; P < .001). CONCLUSION: Use of an AP for more than 33 days and a CL for more than 10 days may carry an increased risk of device-associated BSI. These cutoff periods are longer than those expected at the time of device placement and indicate the importance of postplacement care.