- Volume 2, Issue 2, 2020

Clostridium difficile infection (CDI) adversely affects patient outcomes. CDI 30-day mortality is 15.2% nationally with some regional variation, but data on recurrence is limited. We assessed outcomes of CDI, in particular recurrence and mortality at Addenbrooke’s Hospital.

Methods

We performed a retrospective analysis of all patients who developed CDI between April 2017 and March 2018. All-cause mortality was assessed at 30 days and 1 year. Recurrence was defined as recurrence of symptoms withC. difficiletoxin positive stool or initiationof C. difficile treatment within 1-year after onset of first/previous episode. First-line therapy was metronidazole or vancomycin according to severity.

Clinical data was collected using a standardised proforma. Risk of recurrence was calculated using Cox’s Hazard method in R.

143 cases of CDI in 103 patients were identified. The median age was 70 years (range 2-98). Recurrence rate was 24.6% at 12-weeks and 30.3% at 1-year. 30-day and 1-year mortality was 14.4% and 39.8%, respectively. Recurrences had longer mean length of stay compared to 1stepisodes (40.3 vs. 18 days, respectively, p<0.05). On univariate analysis, no factors predicted recurrence; acute kidney injury, C-reactive protein, toxic megacolon, Charlson comorbidity score and age predicted mortality.

Conclusions

CDI carries a significant mortality and recurrence rate placing a large burden on hospital resources. The majority of recurrences occur within 12 weeks of 1stepisode, and patients’ risk could not be accurately defined in this sample. Newer therapies with reported lower recurrence rates should be considered as 1stline therapy within our Trust.

The 2019 National Diabetes Foot Care Audit shows 2.7% of patients with a diabetic foot ulcer underwent major amputation within six months and 14% died within twelve months. Our OPAT service treats such patients referred from inpatient wards and via the limb salvage clinic as an admission avoidance scheme. A review compared outcomes between these referrals and the national data.

The OPAT database identified patients referred via an inpatient ward and the clinic. Each patient was then reviewed for each of the following criteria:

1. Was the patient alive and ulcer free at 12 weeks?

2. Had the patient had a major amputation within six months?

3. Was the patient still alive after 12 months?

100 patients were reviewed; 50 referred by inpatient wards and 50 referred by the clinic as admission avoidance patients.

In both categories, 94% of patients were alive after twelve weeks, with 12% being ulcer-free in the inpatient category compared with 18% in the admission avoidance group. 6% had a major amputation within six months in the inpatient group, compared with none in the admission avoidance group. 16% of patients in the inpatient group had died within 12 months of treatment, compared with 10% of admission avoidance patients.

OPAT patients receiving treatment for diabetic foot infections have similar outcomes to those in the national audit. No extra harm is being done to those referred to OPAT without hospital admission.

An evidence gap exists in anti-fungal diagnostic practice following abdominal surgery, especially when compared to haem-oncology counterparts. In light of the recent Anti-fungal Stewardship CQUIN, our study addresses the utility of serum (1,3)-β-D-Glucan (BDG) testing post-gastrointestinal surgery.

We identified positive BDG results (>/=80pg/mL) on ITU and surgical wards in 3 major institutions in the Bristol area. Those with a ‘history of abdominal surgery

110 patients with positive results were identified. 19 (17.3%) of these had a history of abdominal surgery. By surgical type, 6 (31.6%) had major abdominal surgery. 6 (31.6%) had pancreatic surgery and 5 (26.3%) small bowel resection. 2 had other types of surgery. The mean BDG score was 286pg/mL. 1 patient had risk factors other than gastrointestinal surgery for a positive BDG result.

Only 1 patient died within 28 days. Patients tested between 0-9, 10-19 or 20-30 days of surgery had mean BDG scores of 329pg/mL, 302pg/mL and 390pg/mL respectively. 40% were tested within 9 days of surgery. There was no clear evidence of invasive fungal infections.

Positive BDG testing is common after surgery, but does not appear to be associated with a significant mortality burden. Ensuring appropriate anti-fungal therapy is essential for treatment, risk reduction and cost containment. More research is needed to identify appropriate testing strategies in patients with abdominal surgery.

Respiratory illness contributes significantly to higher ED attendance during winter months. Polymerase chain reaction (PCR) testing of nasopharyngeal swabs (NPS) for respiratory viruses is a key investigation, with positive influenza results having both clinical and infection control implications. In response to ED colleagues requesting clear and concise guidance, we undertook a QIP to improve management of seasonal influenza.

Methods

A survey of 10 questions was sent to all Doctors and Advanced Care Practitioners (ACPs) working in the ED, and the results collated.

There were 21 survey respondents, the majority were registrars. 81% correctly identified how to request influenza testing and 95% knew the symptoms. 90% identified which risk groups should be treated, which personal protective equipment (PPE) should be donned, and suggested Oseltamavir as their treatment of choice. However only 29% of respondents knew where to find the trust guidelines and only 10% correctly prescribed prophylaxis to contacts. 95% would review a discharged case found to have influenza on testing and 67% would treat this case if they were in an at risk group.

Discussion and Conclusions

The results show that the majority of staff surveyed correctly identified the symptoms of flu, infection control precautions and those requiring treatment. However, knowledge regarding the location of guidelines, management of contacts and the use of agents other than oseltamivir was low. Based on these results we developed a single-page influenza testing algorithm aiming to improve management in A&E, and will reassess staff knowledge following the introduction of this.

Biofilm is defined as a community where bacterial cells encased in a matrix of extracellular polymeric substances adhere to each other and/or to a surface. In food industry, foodborne pathogens like Salmonella are capable of forming biofilms on open surfaces. We have shown anti-biofilm effects of ε-poly-lysine (PL) and milk serum protein (MSP) against various bacteria. In this study, peptides derived from egg was investigated for anti-biofilm effects on foodborne pathogens.

Effects of several kinds of peptides, including 3 kinds of hydrolysates derived from egg, together with PL and MSP, on biofilm formation of 4 kinds of foodborne pathogens (Escherichia coli O157:H7, S. Typhimurium, Staphylococcus aureus and Listeria monocytogenes) were investigated on microtiter plates through biomass quantification with crystal violet staining.

Both 0.01% PL and 0.25% MSP significantly decrease biofilm formation of all the pathogens, while PL was more effective than MSP against gram-negative bacteria. All the hydrolysates showed considerable effect under high concentration (1%), among them hydrolysate 2 was more effective than the others since it inhibited biofilm formation of S.Typhimurium, even under concentration of 0.1%.

The egg white hydrolysate contains some antibacterial peptides that could modulate biofilm formation of S.Typhimurium and other pathogens, which could be beneficial to develop new strategies to combat biofilm infections.

Many health issues are associated with deprivation and some evidence exists that antimicrobial prescribing is higher in deprived groups. This study examined the relationship between antimicrobial resistance in E coli isolates from the population of the Scottish Borders and deprivation as assessed by the Scottish Index of Multiple Deprivation.

Data regarding urine samples submitted for diagnostic purposes which had been reported as growing E coli was extracted. Antimicrobials for which susceptibility testing had been performed were mapped to standardised antimicrobial categories definitions to produce an index of overall antimicrobial resistance. UK postcode data linked to the specimen data was mapped to data zones. The proportion of E. coli isolates within each datazone with different categories of overall resistance was calculated and plotted against its associated Scottish Index of Multiple Deprivation decile.

No association was found between overall antimicrobial resistance in E. coli urinary isolates and SIMD.

During this time period in the Scottish Borders, antimicrobial resistance in E. coli does not show an association with deprivation.

Escherichia coli is a common cause of blood stream infections (BSI) in the UK. Published figures for E. coli BSI show higher rates in specialist cancer centres than in other hospitals, but the aetiology in oncology patients is not fully understood.

Methods

Five UK cancer centres coll aborated to review how E. coli affects oncology patients. A key part of this work has been an audit of all cases of E.coli BSI in patients in 2019 that met UK HCAI surveillance definitions. A multidisciplinary team of clinicians, nurses and pharmacists designed the audit to include >60 variables which may affect cancer patients.

The risk factors for E. coli BSI among these cancer patients showed marked differences from those seen in the general UK population. The affected population was younger; there was higher rate of hospital-onset infections ; and, taking into account a number of healthcare interactions, the potential for healthcare associated infections was much higher. There was also a higher associated 30-day mortality and high rates of antimicrobial resistance in BSI isolates. Common univariate risk factors associated with BSI included use of SACT, neutropaenia, presence of acute kidney injury, presence of an invasive device, antimicrobial therapy, use of PPIs and a lack of independent hydration. By contrast, haematopoietic stem cell transplantation, mucositis and recent surgery were less common associations.

This audit demonstrates differences between risk factors seen in cancer patients with E.coli BSI and may explain why rates are higher in cancer centres.

Worldwide, several clinical screening tools (including EWS, SOFA, qSOFA, SIRS and CURB65) are used on admission to identify patients at risk of sepsis-related mortality. However their ability to accurately predict mortality remains controversial. The purpose of this study was to evaluate whether the predictive performance of these tools is affected by the timing of their use.

Methods

A systematic literature search was performed using PubMed, identifying studies in adult patients with a suspected admission diagnosis of infection, sepsis or pneumonia, in which screening tools were used to predict mortality. Meta-regression analysis was performed on included studies to identify factors affecting the tool’s ability to predict mortality, with a focus on score timing.

From 3901 abstracts screened, 49 studies met inclusion criteria, comprising 421,006 patients and 13 clinical screening tools. No significant difference was found between any predictive tool and mortality. Of all variables considered (size of study, setting, diagnostic group, timing), only the timing related to admission affected predictive value of the tool. Studies that reported using purely physiological measures were less sensitive, marginally more specific, but had generally poorer predictive ability than those which included additional biochemical measures.

Clinicians must recognise that the performance of clinical screening tools is largely related to when they are used, not the individual tool. Given such tools are used on admission to identify risk of sepsis-related mortality, future studies must consider admission scores rather than those further into patients’ admission, to avoid over-reporting any tool’s predictive ability.

The WHO recommends treatment of trachoma with community-wide mass drug administration (MDA) with a single dose of azithromycin as part of the SAFE strategy (surgery, antibiotics, facial cleanliness and environmental improvement). In the Solomon Islands, this programme had demonstrable collateral benefit by reducing the prevalence of urogenital Chlamydia trachomatis(Ct) infections. We evaluated the impact of this treatment on population genetics of urogenital Ct.

Methods

Two vaginal swabs were collected from consecutive women attending antenatal clinics during cross-sectional surveys before and after MDA. For every swab positive for Ctinfection, DNA was extracted from the second swab, enriched and sequenced using paired-end sequencing. Whole-genome sequences were aligned against selected references. Diversity was assessed using genome-wide pairwise diversity and a high-resolution multi-locus sequence typing (hr-MLST-6) scheme. ARIBA software was used to test for evidence of antimicrobial resistance to macrolides.

Whole-genome sequence data was obtained from 23/49 (47%) pre-MDA and 32/41 (78%) post-MDA Ct-positive samples. Most strains were serotype E and F, and tissue tropism genes were consistent with their urogenital nature. Genetic diversity of Ctwas lower by both pairwise and hr-MLST-6 diversity metrics in the post-MDA sample than the pre-MDA sample. There was no evidence of mutations known to confer resistance to macrolides in any of the samples collected.

Conclusions

Reduced diversity after MDA may represent selection pressure from mass antibiotic delivery. The absence of antimicrobial resistance is encouraging. The collateral impact (both positive and negative) of large-scale preventative chemotherapy programmes should be considered when deciding whether should be implemented.

Acute diarrhoeal syndromes are usually self-limiting, but diagnostic testing and treatment may be required in some instances. Stool cultures require a significant level of technologist expertise and are labour intensive. The BD MAX™ Enteric Bacterial Panel detects over 90% of bacteria causing infectious gastroenteritis and provide rapid diagnosis. The aim of this study is to assess the diagnostic and clinical value of this rapid diagnostic tool.

Fresh stool samples received from 68 patients were cultured according to SMI methods, and by BD MAX™ Enteric. Further 25 frozen samples were processed by both methods. Any discrepancies between the two methods where sent to reference laboratory for confirmation.

Five samples (4 fresh and one frozen) were excluded from the study due to PCR inhibition. The turnaround time was 48 hours and 4-5 days for negative and positive culture respectively. BD MAX™ Enteric provided same day result. The sensitivity of BD MAX™ Enteric was 100% for fresh samples but this was reduced to 66% if performed on frozen samples. The rapid availability of negative results guided further clinical investigation and management. While the positive results allowed timely implementation of infection control management and guided antibiotic decision process.

BD MAX™ is sensitive and provides same-day results. This allowed implementation of infection control measures in timely manner and guided further patient management. However, as this panel is restricted to bacterial causes of diarrhoea, if PCR there will be a need for further testing to exclude other possible infectious causes

Anecdotal experience suggested there were areas for improvement in meningitis management. To address this, we conducted a complete audit cycle of the management of meningitis in adult patients at Arrowe Park Hospital.

Method:

We utilised the abbreviated audit tool from the McGill et al 2016 meningitis guidelines.

Time period: 1/1/2017 to 31/12/2017. Cases audited: 20

A series of interventions were made.

Time period for second cycle: 1/2/2019 to 31/5/2019. Cases audited: 6

Audit standards were met for 1 out of 14 criteria for the first cycle and 2 out of 14 criteria for the second cycle.

Of note, there was reasonable compliance with empiric choice of antibiotic (80% à 83%), definitive choice of antimicrobials (95% à83%) and duration of antimicrobials (84% à 100%).

Improvements in investigations were seen in the second cycle:

1.Pneumococcal and Meningococcal EDTA PCR was sent (15% à 67%)

2.CSF glucose with concurrent plasma glucose sent (6.3% à 67%)

3.CSF for pneumococci and meningococci sent in all cases of suspected bacterial meningitis (22% à 67%)

The re-audit identified no improvement in the following areas:

1.Blood cultures taken within 1 h of arrival at hospital (30% à 33%)

2.LP performed within 1 h of arrival at hospital provided that it is safe to do so (0% à 0%)

3.Antibiotics started within 1 hr of arrival in hospital (35% à 33%)

In both audit cycles, 0% of patients were made aware of voluntary sector support.

Whilst improvements were achieved, there remains considerable scope for further improvement.