The perils of PCR-based diagnosis of Clostridioides difficile infections: Painful lessons from clinical trials

Diagnostic tests favoured to detect C. difficile infections (CDI) have undergone successive changes. The problem of over-diagnosis with polymerase chain reaction (PCR) testing is recognized in the clinical setting; here we discuss the parallel of the clinical trial setting. We summarize and discuss four examples of the impact of method used to diagnose CDI on clinical trial outcomes. Bezlotoxumab, a human monoclonal antibody neutralizing toxin B, was found to be protective against recurrent CDI (rCDI) in clinical trials. A post hoc analysis showed that the magnitude of the relative reduction in rCDI rates of bezlotoxumab over placebo in patients diagnosed with toxin-based testing was almost double that in patients diagnosed with PCR. SER-109, a microbiome therapeutic developed to prevent rCDI, showed promise in a phase 1b trial, but results were not replicated in a phase 2 trial in which diagnosis was in majority PCR-based. Surotomycin, an oral lipopeptide antibiotic, was found to be non-inferior to vancomycin in phase 2 study, but development was discontinued after unfavourable phase 3 results in which the majority of CDI were diagnosed by PCR. Finally, a C. difficile vaccine program for a toxoid vaccine developed by Sanofi/Pasteur was terminated after interim analysis of a phase 3 trial, in which CDI diagnosis was based solely on PCR. We highlighted the perils of using PCR alone in studies involving different aspects of C. difficile clinical research, including immunotherapies, microbiome-based therapies, treatments, and vaccines. The importance of designing C. difficile clinical trials with careful consideration to the diagnostic testing method cannot be overemphasized.

Ceftaroline fosamil therapy in patients with acute bacterial skin and skin-structure infections with systemic inflammatory signs: A retrospective dose comparison across three pivotal trials

This post-hoc analysis compared the pharmacokinetics and clinical outcomes of ceftaroline fosamil 600 mg every 12 (q12h) versus every 8 hours (q8h) in patients with acute bacterial skin and skin-structure infection (ABSSSI) and signs of sepsis. Clinical outcomes at test-of-cure in patients with ABSSSI and systemic inflammatory signs/systemic inflammatory response syndrome (SIRS) as well as ceftaroline minimum inhibitory concentrations (MICs) against baseline pathogens were compared between the COVERS trial (ceftaroline fosamil 600 mg q8h, 2-h infusion) and the CANVAS 1 and 2 trials (ceftaroline fosamil 600 mg q12h, 1-h infusion). Ceftaroline exposure among patients in COVERS with or without markers of sepsis was compared using population pharmacokinetic modelling. In COVERS, 62% (312/506) and 41% (208/506) of ceftaroline fosamil-treated patients had ≥1 systemic inflammatory sign or SIRS, respectively, compared with 55% (378/693) and 22% (155/693), respectively, in the CANVAS trials. Clinical cure rates for the modified intent-to-treat population in COVERS and CANVAS were similar for ceftaroline fosamil-treated patients with ≥1 sign of sepsis [82% (255/312) and 85% (335/394)] and for those with SIRS [84% (168/199) and 85% (131/155)]. Ceftaroline MIC distributions were similar across trials. Sepsis did not affect predicted individual steady-state ceftaroline exposure. Clinical cure rates in patients with ≥1 systemic inflammatory sign or SIRS were comparable for both ceftaroline fosamil dosage regimens. Pathogen susceptibilities to ceftaroline were similar across trials. Ceftaroline exposure was not affected by disease severity. Ceftaroline fosamil 600 mg q12h is a robust dosage regimen for most ABSSSI patients with sepsis [ClinicalTrials.gov ID: NCT01499277, NCT00424190, NCT00423657].

Valuing antibiotics: The role of the hospital clinician

The global public health threat of antibiotic-resistant infections as well as the lack of new treatments in clinical development is a critical issue. Reasons for this include diminished commercial incentives for pharmaceutical companies to develop new antibiotics, which part-reflects a shift in antibiotic marketing paradigm from broad deployment to targeted therapy in relatively small patient populations. Such changes are encouraged by antimicrobial stewardship (AMS). Other factors include a lack of recognition in the traditional assessment of new antibiotics by regulators, health technology assessors and payers of the broad range of benefits of new agents, particularly their value to health care, economies and society. Recognising the seriousness of the situation, there have been recent changes and proposals by regulators for modification of the assessment process to accommodate a broader range of acceptable data supporting new drug applications. There is also increasing recognition by some payers of the societal benefit of new antibiotics and the need for financial incentives for those developing high-priority antibiotics. However, progress is slow, with recent publications focusing on industry and strategic perspectives rather than clinical implications. In this opinion piece, we therefore focus on clinicians and the practical steps they can take to drive and contribute to increasing awareness and understanding of the value of antibiotics. This includes identifying and gathering appropriate alternative data sources, educating on AMS and prescribing habits, and contributing to international antibiotic susceptibility surveillance models.

Service evaluation of alcohol-release door plates: an addition to hand hygiene

A service evaluation was designed to examine the effect of installation of alcohol-releasing Surfaceskins doorplates on routine alcohol hand gel hygiene use by healthcare workers. There was an approximate doubling increase in healthcare worker use of alcohol hand gel dispensers following the installation of Surfaceskins doorplates in two operating theatre suites. No evidence was found that Surfaceskins doorplates replaced routine hand hygiene. It is concluded that these devices represent a useful adjunct to routine hand hygiene practice in healthcare environments, and potentially in other settings (e.g. washrooms, restaurants) where frequent contact with doors could undermine infection prevention practice.

Clostridium difficile trehalose metabolism variants are common and not associated with adverse patient outcomes when variably present in the same lineage

Background

Clostridium difficile ribotype-027, ribotype-078, and ribotype-017 are virulent and epidemic lineages. Trehalose metabolism variants in these ribotypes, combined with increased human trehalose consumption, have been hypothesised to have contributed to their emergence and virulence.

Methods

5232 previously whole-genome sequenced C. difficile isolates were analysed. Clinical isolates were used to investigate the impact of trehalose metabolism variants on mortality. Import data were used to estimate changes in dietary trehalose. Ribotype-027 virulence was investigated in a clinically reflective gut model.

Findings

Trehalose metabolism variants found in ribotype-027 and ribotype-017 were widely distributed throughout C. difficile clade-2 and clade-4 in 24/29 (83%) and 10/11 (91%) of sequence types (STs), respectively. The four-gene trehalose metabolism cluster described in ribotype-078 was common in genomes from all five clinically-important C. difficile clades (40/167 [24%] STs).

The four-gene cluster was variably present in 208 ribotype-015 infections (98 [47%]); 27/208 (13%) of these patients died within 30-days of diagnosis. Adjusting for age, sex, and infecting ST, there was no association between 30-day all-cause mortality and the four-gene cluster (OR 0.36 [95%CI 0.09–1.34, p = 0.13]).

Synthetic trehalose imports in the USA, UK, Germany and the EU were  < 1 g/capita/year during 2000–2006, and  < 9 g/capita/year 2007–2012, compared with dietary trehalose from natural sources of ~100 g/capita/year.

Trehalose supplementation did not increase ribotype-027 virulence in a clinically-validated gut model.

Interpretation

Trehalose metabolism variants are common in C. difficile. Increases in total dietary trehalose during the early-mid 2000s C. difficile epidemic were likely relatively minimal. Alternative explanations are required to explain why ribotype-027, ribotype-078 and ribotype-017 have been successful.

Funding

National Institute for Health Research. Gut model experiments only: Hayashibara Co. Ltd.

A Review of Mixed Strain Clostridium difficile Colonization and Infection

Given that Clostridium difficile is not part of the normal human microbiota, if multiple strains are to accumulate in the colon implies successive exposure events and/or persistent colonization must occur. Evidence of C. difficile infection (CDI) with more than one strain was first described in 1983. Despite the availability of increasingly discriminatory bacterial fingerprinting methods, the described rate of dual strain recovery in patients with CDI has remained stable at ∼5–10%. More data are needed to determine when dual strain infection may be harmful. Notably, one strain may block the establishment of and infection by another. In humans, patients colonized by non-toxigenic C. difficile strain are at a lower risk of developing CDI. Further studies to elucidate the interaction between co-infecting or colonizing and infecting C. difficile strains may help identify potential exploitable mechanisms to prevent CDI.

A Role for Tetracycline Selection in Recent Evolution of Agriculture-Associated Clostridium difficile PCR Ribotype 078

The increasing clinical importance of human infections (frequently severe) caused by Clostridium difficile PCR ribotype 078 (RT078) was first reported in 2008. The severity of symptoms (mortality of ≤30%) and the higher proportion of infections among community and younger patients raised concerns. Farm animals, especially pigs, have been identified as RT078 reservoirs. We aimed to understand the recent changes in RT078 epidemiology by investigating a possible role for antimicrobial selection in its recent evolutionary history. Phylogenetic analysis of international RT078 genomes (isolates from 2006 to 2014, n = 400), using time-scaled, recombination-corrected, maximum likelihood phylogenies, revealed several recent clonal expansions. A common ancestor of each expansion had independently acquired a different allele of the tetracycline resistance gene tetM Consequently, an unusually high proportion (76.5%) of RT078 genomes were tetM positive. Multiple additional tetracycline resistance determinants were also identified (including efflux pump tet40), frequently sharing a high level of nucleotide sequence identity (up to 100%) with sequences found in the pig pathogen Streptococcus suis and in other zoonotic pathogens such as Campylobacter jejuni and Campylobacter coli Each RT078 tetM clonal expansion lacked geographic structure, indicating rapid, recent international spread. Resistance determinants for C. difficile infection-triggering antimicrobials, including fluoroquinolones and clindamycin, were comparatively rare in RT078. Tetracyclines are used intensively in agriculture; this selective pressure, plus rapid, international spread via the food chain, may explain the increased RT078 prevalence in humans. Our work indicates that the use of antimicrobials outside the health care environment has selected for resistant organisms, and in the case of RT078, has contributed to the emergence of a human pathogen.IMPORTANCEClostridium difficile PCR ribotype 078 (RT078) has multiple reservoirs; many are agricultural. Since 2005, this genotype has been increasingly associated with human infections in both clinical settings and the community. Investigations of RT078 whole-genome sequences revealed that tetracycline resistance had been acquired on multiple independent occasions. Phylogenetic analysis revealed a rapid, recent increase in numbers of closely related tetracycline-resistant RT078 (clonal expansions), suggesting that tetracycline selection has strongly influenced its recent evolutionary history. We demonstrate recent international spread of emergent, tetracycline-resistant RT078. A similar tetracycline-positive clonal expansion was also identified in unrelated nontoxigenic C. difficile, suggesting that this process may be widespread and may be independent of disease-causing ability. Resistance to typical C. difficile infection-associated antimicrobials (e.g., fluoroquinolones, clindamycin) occurred only sporadically within RT078. Selective pressure from tetracycline appears to be a key factor in the emergence of this human pathogen and the rapid international dissemination that followed, plausibly via the food chain.

Abstract GS4-05: Dose escalated simultaneous integrated boost radiotherapy for women treated by breast conservation surgery for early breast cancer: 3-year adverse effects in the IMPORT HIGH trial (CRUK/06/003)

Background

IMPORT HIGH is a randomised, multi-centre phase III trial testing dose escalated simultaneous integrated boost (SIB) against sequential boost each delivered by intensity modulated radiotherapy (IMRT) for early stage breast cancer with higher risk of local relapse. The primary endpoint was initially breast induration at 3 years, requiring 840 patients; accrual was extended (target 2568) with the new primary endpoint of local relapse. We report adverse effects (AE) at 3 years.

Methods

Women age ≥18 after breast conservation surgery for pT1-3 pN0-pN3a M0 invasive carcinoma were eligible. Randomisation was 1:1:1 between 40Gy/15F to whole breast (WB) + 16Gy/8F sequential photon boost to tumour bed (40+16Gy), 36Gy/15F to WB, 40Gy to partial breast + 48Gy (48Gy) or + 53Gy (53Gy) in 15F SIB to tumour bed. AEs were assessed annually by clinicians in all patients and in a planned sub-set (840) of patients by photographs at 3 years and by patients at 6 months, 1 and 3 years. AE scores were dichotomised as none/mild vs marked for photographs and none/mild vs moderate/marked for patients and clinicians. Fisher's exact tests compared groups; principal comparison (protocol-specified) between 53Gy and 48Gy (p&lt;0.01 defined as statistical significance).

Results

2617 women consented between 03/2009 and 09/2015 from 39 UK radiotherapy centres. Median follow-up was 49.1 (IQR 36.8-63.2) months. Median age was 49 (IQR 44-56); 9%, 38% & 53% were tumour grade 1, 2 & 3 respectively; 30% were node positive. 66% received chemotherapy and 73% endocrine therapy. 3-year AE data were available for 2017 clinician assessments, 641 photographs and 842 patient assessments. Proportions of patients with marked AEs were low overall. Rates of moderate/marked AEs at 3 years were broadly similar between the randomised groups; with a suggestion of a slightly increased risk for breast induration in 53Gy compared with control (borderline significance).

AE at 3 years 40+16Gy n(%)48Gy n(%)53Gy n(%)ClinicianBreast induration;N656668654None451 (69)483 (72)445 (68)Mild167 (25)141 (21)146 (22)Moderate32 (5)42 (6)56 (9)Marked6 (1)2 (1)7 (1)P-value 0.57010.0102  0.0443Breast shrinkage;N655669654None442 (68)472 (71)448 (69)Mild167 (26)161 (24)166 (25)Moderate40 (6)33 (5)35 (5)Marked6 (1)3 (1)5 (1)P-value 0.25410.5772  0.6373Breast distortion;N656669654None451 (69)464 (69)442 (68)Mild169 (26)170 (25)170 (26)Moderate33 (5)32 (5)38 (6)Marked3 (1)3 (1)4 (1)P-value 0.90310.4862  0.4113PatientChange in breast appearance;N287264285None38 (13)50 (19)58 (20)Mild164 (57)151 (57)142 (50)Moderate57 (20)45 (17)54 (19)Marked28 (10)18 (7)31 (11)P-value 0.14910.9992  0.1243PhotographChange in breast appearance;N218210213None183 (84)185 (88)177 (83)Mild25 (11)23 (11)32 (15)Marked10 (5)2 (1)4 (2)P-value 0.03610.1732  0.6853148Gy v 40+16Gy; 253Gy v 40+16Gy; 353Gy v 48Gy

Conclusions

These results represent the largest and most mature reported AE outcomes of breast SIB within a clinical trial. At 3 years, rates of moderate/marked AEs were similar between SIB IMRT and WB + sequential boost IMRT delivered over 3 and 4.5 weeks respectively.

Citation Format: Coles CE, Griffin CL, Kirby AM, Haviland JS, Titley JC, Benstead K, Brunt AM, Chan C, Ciurlionis L, Din OS, Donovan EM, Eaton DJ, Harnett AN, Hopwood P, Jefford ML, Jenkins PJ, Lee CE, McCormack M, Sherwin L, Syndikus I, Tsang Y, Twyman NI, Ventikaraman R, Wickers S, Wilcox MH, Bliss JM, Yarnold JR. Dose escalated simultaneous integrated boost radiotherapy for women treated by breast conservation surgery for early breast cancer: 3-year adverse effects in the IMPORT HIGH trial (CRUK/06/003) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS4-05.

Cadazolid for the treatment of Clostridium difficile infection: results of two double-blind, placebo-controlled, non-inferiority, randomised phase 3 trials

BACKGROUND

Cadazolid is a novel quinoxolidinone antibiotic developed for treating Clostridium difficile infection. We aimed to investigate the safety and efficacy of cadazolid compared with vancomycin in patients with C difficile infection.

METHODS

IMPACT 1 and IMPACT 2 were identically designed, multicentre, double-blind, placebo-controlled, non-inferiority, randomised phase 3 trials. IMPACT 1 was done in Australia, Brazil, Canada, France, Germany, Italy, the Netherlands, Peru, Poland, Romania, Spain, and the USA, and IMPACT 2 was done in Argentina, Belgium, Brazil, Canada, Chile, Croatia, Czech Republic, Greece, Hungary, Israel, Romania, Slovakia, South Korea, the UK, and the USA. Patients (aged 18 years or older) with mild-to-moderate or severe C difficile infection (diarrhoea with positive glutamate dehydrogenase and toxin A or B enzyme immunoassays) were randomly assigned (1:1) with a randomisation list stratified by centre and C difficile infection episode type (block size of four), and allocation was masked to investigators and participants. Patients received either oral cadazolid 250 mg twice daily with vancomycin-matching placebo capsule four times daily or oral vancomycin 125 mg four times a day with cadazolid-matching placebo suspension twice daily for 10 days, with 30 days of follow-up. The primary efficacy outcome was non-inferiority (margin -10%) of cadazolid versus vancomycin for clinical cure in the modified intention-to-treat and per-protocol populations. Clinical cure was defined as resolution of diarrhoea with no additional treatment for C difficile infection. These trials are registered with ClinicalTrials.gov, numbers NCT01987895 (IMPACT 1) and NCT01983683 (IMPACT 2).

FINDINGS

Between March 28, 2014, and March 24, 2017, for IMPACT 1, and Dec 13, 2013, and May 2, 2017, for IMPACT 2, 1263 participants were randomly assigned to receive cadazolid (306 in IMPACT 1 and 298 in IMPACT 2) or vancomycin (326 in IMPACT 1 and 311 in IMPACT 2). In the modified intention-to-treat population in IMPACT 1, 253 (84%) of 302 had clinical cure in the cadazolid group versus 271 (85%) of 318 in the vancomycin group. In IMPACT 2, 235 (81%) of 290 versus 258 (86%) of 301 had clinical cure. In the per-protocol population, 247 (88%) of 282 versus 264 (92%) of 288 had clinical cure in IMPACT 1 and 214 (87%) of 247 versus 237 (92%) of 259 in IMPACT 2. Non-inferiority for clinical cure to vancomycin was shown in IMPACT 1 but not in IMPACT 2 (IMPACT 1 treatment difference: -1·4 [95% CI -7·2 to 4·3] for modified intention to treat and -4·1 [-9·2 to 1·0] for per protocol; IMPACT 2: -4·7 [-10·7 to 1·3] for modified intention to treat and -4·9 [-10·4 to 0·6] for per protocol). The safety and tolerability profiles of the two antibiotics were similar.

INTERPRETATION

Cadazolid was safe and well tolerated but did not achieve its primary endpoint of non-inferiority to vancomycin for clinical cure in one of two phase 3 C difficile infection trials. Therefore, further commercial development of cadazolid for C difficile infection is unlikely.

FUNDING

Actelion Pharmaceuticals.

Correlation between restriction endonuclease analysis and PCR ribotyping for the identification of Clostridioides (Clostridium) difficile clinical strains

Restriction endonuclease analysis (REA) and PCR ribotyping are two typing systems that have been frequently utilized for molecular epidemiologic characterization of Clostridioides (Clostridium) difficile. To correlate typing data obtained from each method, we performed both REA and PCR ribotyping on a large and diverse set of historical and contemporary C. difficile infection clinical isolates. Eighty isolates were selected from each reference laboratory in the United States (Microbiology Reference Laboratory, Hines VA Medical Center) and United Kingdom (Clostridium difficile Network for England and Northern Ireland laboratory, University of Leeds). The 160 isolates were assigned to 82 unique ribotypes and 51 unique REA groups (116 unique REA types). In general, concordance between typing methods was good. Dendrogram analysis of PCR ribotype band patterns demonstrated close genetic relationships among strain types with discordant REA and ribotype assignments. While REA typing was more discriminatory, several REA types in this study were further discriminated by PCR ribotyping, indicating that discriminatory value of these typing methods may be strain dependent. These data will assist with molecular epidemiologic surveillance of strains identified by these two commonly used C. difficile typing systems.

Management of complicated skin and soft tissue infections with a special focus on the role of newer antibiotics

Complicated skin and soft tissue infections (cSSTIs) represent the severe form of infectious disease that involves deeper soft tissues. Involvement of methicillin-resistant Staphylococcus aureus (MRSA) further complicates cSSTI with increased hospitalization, health care costs, and overall mortality. Various international guidelines provide recommendations on the management of cSSTIs, with the inclusion of newer antibiotics. This literature-based review discusses the overall management of cSSTI, including appropriate use of antibiotics in clinical practice. Successful treatment of cSSTIs starts with early and precise diagnosis, including identification of causative pathogen and its load, determination of infection severity, associated complications, and risk factors. The current standard-of-care for cSSTIs involves incision, drainage, surgical debridement, broad-spectrum antibiotic therapy, and supportive care. In recent years, the emergence of newer antibiotics (eg, ceftaroline, tigecycline, daptomycin, linezolid, etc) has provided clinicians wider options of antimicrobial therapy. Selection of antibiotics should be based on the drug characteristics, effectiveness, safety, and treatment costs, alongside other aspects such as host factors and local multidrug resistance rates. However, larger studies on newer antibiotics are warranted to refine the decision making on the appropriate antimicrobial therapy. Local Antimicrobial Stewardship Program strategies in health care settings could guide clinicians for early initiation of specific treatments to combat region-specific antimicrobial resistance, minimize adverse effects, and to improve outcomes such as reduction in Clostridium difficile infections. These strategies involving iv-to-oral switch, de-escalation to narrow-spectrum antibiotics, and dose optimization have an impact on the overall improvement of cSSTI therapy outcomes, especially in countries like Singapore that has a high disease burden.

Trends over time in Escherichia coli bloodstream infections, urinary tract infections, and antibiotic susceptibilities in Oxfordshire, UK, 1998-2016: a study of electronic health records

BACKGROUND

Escherichia coli bloodstream infections are increasing in the UK and internationally. The evidence base to guide interventions against this major public health concern is small. We aimed to investigate possible drivers of changes in the incidence of E coli bloodstream infection and antibiotic susceptibilities in Oxfordshire, UK, over the past two decades, while stratifying for time since hospital exposure.

METHODS

In this observational study, we used all available data on E coli bloodstream infections and E coli urinary tract infections (UTIs) from one UK region (Oxfordshire) using anonymised linked microbiological data and hospital electronic health records from the Infections in Oxfordshire Research Database (IORD). We estimated the incidence of infections across a two decade period and the annual incidence rate ratio (aIRR) in 2016. We modelled the data using negative binomial regression on the basis of microbiological, clinical, and health-care-exposure risk factors. We investigated infection severity, 30-day all-cause mortality, and community and hospital amoxicillin plus clavulanic acid (co-amoxiclav) use to estimate changes in bacterial virulence and the effect of antimicrobial resistance on incidence.

FINDINGS

From Jan 1, 1998, to Dec 31, 2016, 5706 E coli bloodstream infections occurred in 5215 patients, and 228 376 E coli UTIs occurred in 137 075 patients. 1365 (24%) E coli bloodstream infections were nosocomial (onset >48 h after hospital admission), 1132 (20%) were quasi-nosocomial (≤30 days after discharge), 1346 (24%) were quasi-community (31-365 days after discharge), and 1863 (33%) were community (>365 days after hospital discharge). The overall incidence increased year on year (aIRR 1·06, 95% CI 1·05-1·06). In 2016, 212 (41%) of 515 E coli bloodstream infections and 3921 (28%) of 13 792 E coli UTIs were co-amoxiclav resistant. Increases in E coli bloodstream infections were driven by increases in community (aIRR 1·10, 95% CI 1·07-1·13; p<0·0001) and quasi-community (aIRR 1·08, 1·07-1·10; p<0·0001) cases. 30-day mortality associated with E coli bloodstream infection decreased over time in the nosocomial (adjusted rate ratio [RR] 0·98, 95% CI 0·96-1·00; p=0·03) group, and remained stable in the quasi-nosocomial (adjusted RR 0·98, 0·95-1·00; p=0·06), quasi-community (adjusted RR 0·99, 0·96-1·01; p=0·32), and community (adjusted RR 0·99, 0·96-1·01; p=0·21) groups. Mortality was, however, substantial at 14-25% across all hospital-exposure groups. Co-amoxiclav-resistant E coli bloodstream infections increased in all groups across the study period (by 11-18% per year, significantly faster than co-amoxiclav-susceptible E coli bloodstream infections; p_{heterogeneity}<0·0001), as did co-amoxiclav-resistant E coli UTIs (by 14-29% per year; p_{heterogeneity}<0·0001). Previous year co-amoxiclav use in primary-care facilities was associated with increased subsequent year community co-amoxiclav-resistant E coli UTIs (p=0·003).

INTERPRETATION

Increases in E coli bloodstream infections in Oxfordshire are primarily community associated, with substantial co-amoxiclav resistance; nevertheless, we found little or no change in mortality. Focusing interventions on primary care facilities, particularly those with high co-amoxiclav use, could be effective in reducing the incidence of co-amoxiclav-resistant E coli bloodstream infections, in this region and more generally.

FUNDING

National Institute for Health Research.

Real-Life Evidence for Tedizolid Phosphate in the Treatment of Cellulitis and Wound Infections: A Case Series

Introduction

Tedizolid phosphate 200 mg, once daily for 6 days, has recently been approved for the treatment of patients with acute bacterial skin and skin structure infections (ABSSSIs) in several countries; however, clinical experience in real-life settings is currently limited. Here, we report on the use of tedizolid with an extended treatment duration for complex and severe ABSSSIs in real-world clinical settings.

Methods

Two patients with cellulitis and two patients with surgical site infection (SSI), aged 26–60 years, were treated with tedizolid phosphate 200 mg, intravenous/oral (IV/PO) or IV only, once daily at four different institutions.

Results

Two morbidly obese patients had non-necrotizing, non-purulent severe cellulitis, which were complicated by sepsis or systemic inflammatory response syndrome plus myositis. One female patient failed on first-line empiric therapy with IV cefalotin, clindamycin and imipenem (3–4 days), and was switched to IV/PO tedizolid (7 + 5 days). One male patient received IV clindamycin plus IV/PO tedizolid (5 + 5 days), but clindamycin was discontinued on Day 3 due to an adverse event. For both patients, clinical signs and symptoms improved within 72 h, and laboratory results were normalized by Days 7 and 8, respectively. Two other patients (one obese, diabetic female with chronic hepatitis and chronic obstructive pulmonary disease) had complicated SSIs occurring 10 days after hernia repair with mesh or 3 months after spinal fusion surgery with metal implant. First patient with previous methicillin-resistant Staphylococcus aureus (MRSA) bacteremia received a 7-day tedizolid IV course empirically. The second patient with culture-confirmed MRSA infection received a 14-day IV course. Both patients responded within 72 h, and local and systemic signs normalized by end of treatment. There were no reports of thrombocytopenia.

Conclusion

Tedizolid phosphate 200 mg for 7–14 days was a favored treatment option for patients with severe/complex ABSSSIs, and was effective following previous treatment failure or in late-onset infections.

Funding

Editorial assistance and the article processing charges were funded by Bayer AG, Berlin, Germany.

Environmental contamination by bacteria in hospital washrooms according to hand-drying method: a multi-centre study

BACKGROUND

Hand hygiene is a fundamental component of infection prevention, but few studies have examined whether hand-drying method affects the risk of dissemination of potential pathogens.

AIM

To perform a multi-centre, internal-crossover study comparing bacterial contamination levels in washrooms with hand-drying by either paper towels (PT) or jet air dryer (JAD; Dyson).

METHODS

A total of 120 sampling sessions occurred over 12 weeks in each of three hospitals (UK, France, Italy). Bacteria were cultured from air, multiple surfaces, and dust. Washroom footfall (patients/visitors/staff) was monitored externally.

FINDINGS

Footfall was nine times higher in UK washrooms. Bacterial contamination was lower in PT versus JAD washrooms; contamination was similar in France and the UK, but markedly lower in Italian washrooms. Total bacterial recovery was significantly greater from JAD versus PT dispenser surfaces at all sites (median: 100-300 vs 0-10 cfu; all P < 0.0001). In the UK and France, significantly more bacteria were recovered from JAD washroom floors (median: 24 vs 191 cfu, P < 0.00001). UK meticillin-susceptible Staphylococcus aureus recovery was three times more frequent and six-fold higher for JAD vs PT surfaces (both P < 0.0001). UK meticillin-resistant S. aureus recovery was three times more frequent (21 vs 7 cfu) from JAD versus PT surfaces or floors. Significantly more enterococci and extended-spectrum β-lactamase (ESBL)-producing bacteria were recovered from UK JAD versus PT washroom floors (P < 0.0001). In France, ESBL-producing bacteria were recovered from dust twice as often during JAD versus PT use.

CONCLUSION

Multiple examples of significant differences in surface bacterial contamination, including by faecal and antibiotic-resistant bacteria, were observed, with higher levels in JAD versus PT washrooms. Hand-drying method affects the risk of (airborne) dissemination of bacteria in real-world settings.

Impact of recurrent Clostridium difficile infection: hospitalization and patient quality of life

Objectives

Data quantifying outcomes of recurrent Clostridium difficile infection (rCDI) are lacking. We sought to determine the UK hospital resource use and health-related quality of life (HRQoL) associated with rCDI hospitalizations.

Patients and methods

A non-interventional study in six UK acute hospitals collected retrospective clinical and resource use data from medical records of 64 adults hospitalized for rCDI and 64 matched inpatient controls with a first episode only (f)CDI. Patients were observed from the index event (date rCDI/fCDI confirmed) for 28 days (or death, if sooner); UK-specific reference costs were applied. HRQoL was assessed prospectively in a separate cohort of 30 patients hospitalized with CDI, who completed the EQ-5D-3L questionnaire during their illness.

Results

The median total management cost (post-index) was £7539 and £6294 for rCDI and fCDI, respectively (cost difference, P = 0.075); median length of stay was 21 days and 15.5 days, respectively (P = 0.269). The median cost difference between matched rCDI and fCDI cases was £689 (IQR=£1873-£3954). Subgroup analysis demonstrated the highest median costs (£8542/patient) in severe rCDI cases. CDI management costs were driven primarily by hospital length of stay, which accounted for >85% of costs in both groups. Mean EQ-5D index values were 46% lower in CDI patients compared with UK population values (0.42 and 0.78, respectively); EQ visual analogue scale scores were 38% lower (47.82 and 77.3, respectively).

Conclusions

CDI has considerable impact on patients and healthcare resources. This multicentre study provides a contemporaneous estimate of the real-world UK costs associated with rCDI management, which are substantial and comparable to fCDI costs.

Comparison of Control of Clostridium difficile Infection in Six English Hospitals Using Whole-Genome Sequencing

Background.

Variation in Clostridium difficile infection (CDI) rates between healthcare institutions suggests overall incidence could be reduced if the lowest rates could be achieved more widely.

Methods.

We used whole-genome sequencing (WGS) of consecutive C. difficile isolates from 6 English hospitals over 1 year (2013–14) to compare infection control performance. Fecal samples with a positive initial screen for C. difficile were sequenced. Within each hospital, we estimated the proportion of cases plausibly acquired from previous cases.

Results.

Overall, 851/971 (87.6%) sequenced samples contained toxin genes, and 451 (46.4%) were fecal-toxin-positive. Of 652 potentially toxigenic isolates >90-days after the study started, 128 (20%, 95% confidence interval [CI] 17–23%) were genetically linked (within ≤2 single nucleotide polymorphisms) to a prior patient’s isolate from the previous 90 days. Hospital 2 had the fewest linked isolates, 7/105 (7%, 3–13%), hospital 1, 9/70 (13%, 6–23%), and hospitals 3–6 had similar proportions of linked isolates (22–26%) (P ≤ .002 comparing hospital-2 vs 3–6). Results were similar adjusting for locally circulating ribotypes. Adjusting for hospital, ribotype-027 had the highest proportion of linked isolates (57%, 95% CI 29–81%). Fecal-toxin-positive and toxin-negative patients were similarly likely to be a potential transmission donor, OR = 1.01 (0.68–1.49). There was no association between the estimated proportion of linked cases and testing rates.

Conclusions.

WGS can be used as a novel surveillance tool to identify varying rates of C. difficile transmission between institutions and therefore to allow targeted efforts to reduce CDI incidence.