An outbreak of meticillin-resistant Staphylococcus aureus colonization in a neonatal intensive care unit: use of a case-control study to investigate and control it and lessons learnt.

AIM: To describe the investigation and management of a meticillin-resistant Staphylococcus aureus (MRSA) outbreak on a neonatal intensive care unit (NICU) and the lessons learnt. METHODS: This was an outbreak report and case-control study conducted in a 40-cot NICU in a tertiary referral hospital and included all infants colonized/infected with gentamicin-resistant MRSA. INTERVENTION: Standard infection-control measures including segregation of infants, barrier precautions, enhanced cleaning, assessment of staff practice including hand hygiene, and increased MRSA screening of infants were implemented. Continued MRSA acquisitions led to screening of all NICU staff. A case-control study was performed to assess staff contact with colonized babies and inform the management of the outbreak. FINDINGS: Eight infants were colonized with MRSA (spa type t2068), one of whom subsequently developed an MRSA bacteraemia. MRSA colonization was significantly associated with lower gestational age; lower birthweight and with being a twin. Three nurses were MRSA colonized but only one nurse (45) was colonized with MRSA spa type t2068. Multivariable logistic regression analysis identified being cared for by nurse 45 as an independent risk factor for MRSA colonization. CONCLUSIONS: Lack of accurate recording of which nurses looked after which infants (and when) made identification of the risk posed by being cared for by particular nurses difficult. If this had been clearer, it may have enabled earlier identification of the colonized nurse, avoiding subsequent cases. This study highlights the benefit of using a case-control study, which showed that most nurses had no association with colonized infants.

Point-prevalence survey of carbapenemase-producing Enterobacteriaceae and vancomycin-resistant enterococci in adult inpatients in a university teaching hospital in the UK.

Infections with carbapenemase-producing Enterobacteriaceae (CPE) and vancomycin-resistant enterococci (VRE) are associated with increased morbidity and mortality, but the carriage rates of CRE and VRE among hospital inpatients are unknown. A point-prevalence survey was conducted to determine CPE and VRE carriage rates in hospitalized adults. Eight hundred and eighteen of 960 (85.2%) adult inpatients were invited to participate in the study. Of these, 595 patients (72.7%) consented and provided specimens. Of 540 samples tested, none were positive for CPE. One hundred and thirty of 540 (24.1%) samples were VRE positive, and 34 of 40 (85%) of wards had cases. Universal screening for CPE may not be cost-effective in low-prevalence settings, but targeted screening of high-risk patients should continue. The optimal screening strategy for VRE remains to be determined, as universal screening and isolation is not feasible in the study setting.

Real-world use of fidaxomicin in a large UK tertiary hospital: how effective is it for treating recurrent disease?

All courses of fidaxomicin use in the study hospital were reviewed. It was used for first recurrence (six times), second recurrence (eight times) and one case of third recurrence. One patients received fidaxomicin as first-line treatment. Eight patients initially responded to therapy; of these, three patients were asymptomatic at 90 days, three patients remained asymptomatic at 30 days, and two patients had recurrences five and nine days after stopping therapy. Four patients failed to respond; of these, two patients required faecal transplantation and one patient required a colectomy. Two patients deteriorated and two patients died. Fidaxomicin was well tolerated. These findings suggest that the utility of fidaxomicin at this stage of infection is unclear.

Antibiotic resistance: what, why, where, when and how?

BACKGROUND: Antibiotic resistance is a threat to the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi. SOURCES OF DATA: Peer-reviewed journal articles, governmental and professional society publications. AREAS OF AGREEMENT AND CONTROVERSY: There is consensus about the development and spread of antibiotic resistance, the reasons for the development of antibiotic resistance and the clinical impact. There is more debate about the most appropriate way of tackling this increasing problem. GROWING POINTS: This review discusses a number of initiatives (local and global) that are being undertaken to protect the antibiotics we currently have available for use and to encourage the development of newer agents.

Impact of routine bedside infectious disease consultation on clinical management and outcome of Staphylococcus aureus bacteraemia in adults.

Staphylococcus aureus bacteraemia (SAB) is a common, serious infection that is associated with high rates of morbidity and mortality. Evidence suggests that infectious disease consultation (IDC) improves clinical management in patients with SAB. We examined whether the introduction of a routine bedside IDC service for adults with SAB improved clinical management and outcomes compared to telephone consultation. We conducted an observational cohort study of 571 adults with SAB at a teaching hospital in the United Kingdom between July 2006 and December 2012. A telephone consultation was provided on the day of positive blood culture in all cases, but an additional bedside IDC was provided after November 2009 (routine IDC group). Compared to patients in the pre-IDC group, those in the routine IDC group were more likely to have a removable focus of infection identified, echocardiography performed and follow-up blood cultures performed. They also received longer courses of antimicrobial therapy, were more likely to receive combination antimicrobial therapy and were more likely to have SAB recorded in the hospital discharge summary. There was a trend towards lower mortality at 30 days in the routine IDC group compared to the pre-IDC group (12% vs. 22%, p 0.07). Our findings suggest that routine bedside IDC should become the standard of care for adults with SAB.

Introduction of an antifungal stewardship programme targeting high-cost antifungals at a tertiary hospital in Cambridge, England.

BACKGROUND: Antifungal stewardship aims to promote the optimal use of antifungals through the careful selection of agents based on patient profile, target organism, toxicity, costs and the likelihood of emergence and spread of resistance. METHODS: We report on an observational prospective 12 month study conducted by an antifungal stewardship team targeting the use of echinocandins (caspofungin and micafungin), voriconazole and liposomal amphotericin B in a tertiary referral hospital in the UK. RESULTS: One-hundred-and-seventy-three patients were reviewed on 294 occasions. Clinical advice was given and implemented during review of 45 (88.2%) of micafungin prescriptions, 70 (78.7%) of those receiving voriconazole, 78 (62.4%) of those receiving liposomal amphotericin B and 3 (27.3%) of those receiving caspofungin. Except for voriconazole, nearly half of all treatments reviewed were stopped or changed. This study found that a crude cost saving of ∼£180 000 in antifungal drugs was generated compared with the previous year. CONCLUSIONS: Using a multidisciplinary team, antifungal stewardship can achieve significant improvements in patient management and it may reduce costs.

Acetabular distraction: an alternative approach to pelvic discontinuity in failed total hip replacement.

A pelvic discontinuity occurs when the superior and inferior parts of the hemi-pelvis are no longer connected, which is difficult to manage when associated with a failed total hip replacement. Chronic pelvic discontinuity is found in 0.9% to 2.1% of hip revision cases with risk factors including severe pelvic bone loss, female gender, prior pelvic radiation and rheumatoid arthritis. Common treatment options include: pelvic plating with allograft, cage reconstruction, custom triflange implants, and porous tantalum implants with modular augments. The optimal technique is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable healing between the two segments. A method of treating pelvic discontinuity using porous tantalum components with a distraction technique that achieves both initial stability and subsequent long-term biological fixation is described.

Impact of cleaning and other interventions on the reduction of hospital-acquired Clostridium difficile infections in two hospitals in England assessed using a breakpoint model.

BACKGROUND: Clostridium difficile infection remains a major challenge for hospitals. Although targeted infection control initiatives have been shown to be effective in reducing the incidence of hospital-acquired C. difficile infection, there is little evidence available to assess the effectiveness of specific interventions. AIM: To use statistical modelling to detect substantial reductions in the incidence of C. difficile from time series data from two hospitals in England, and relate these time points to infection control interventions. METHODS: A statistical breakpoints model was fitted to likely hospital-acquired C. difficile infection incidence data from a teaching hospital (2002-2009) and a district general hospital (2005-2009) in England. Models with increasing complexity (i.e. increasing the number of breakpoints) were tested for an improved fit to the data. Partitions estimated from breakpoint models were tested for individual stability using statistical process control charts. Major infection control interventions from both hospitals during this time were grouped according to their primary target (antibiotics, cleaning, isolation, other) and mapped to the model-suggested breakpoints. FINDINGS: For both hospitals, breakpoints coincided with enhancements to cleaning protocols. Statistical models enabled formal assessment of the impact of different interventions, and showed that enhancements to deep cleaning programmes are the interventions that have most likely led to substantial reductions in hospital-acquired C. difficile infections at the two hospitals studied.

Mammary gland differentiation by early life exposure to enantiomers of the soy isoflavone metabolite equol.

The role of soy in reducing breast cancer risk has been suggested to be associated with early exposure to isoflavones, which alter mammary gland morphology. The objective of the study was to determine the effect of dietary exposure to the enantiomers of a key soy isoflavone metabolite, equol, on mammary gland development and later chemoprotection using the DMBA-induced animal model of breast cancer. Animals were exposed to S-(-)equol or R-(+)equol (250 mg/kg diet) during the neonatal (0-21 days) or prepubertal (21-35 days) periods only. Histological evaluation of the mammary glands showed that both enantiomers fed neonatally via the dam led to significant precocial mammary gland differentiation. By day 50, early S-(-)equol or R-(+)equol exposure resulted in a decrease in immature terminal end structures and an increase in mature lobules, suggesting an early 'imprinting' effect. Despite these morphological changes to the mammary gland, neonatal and prepubertal exposure to equol had no long-term chemoprevention against mammary tumors induced by DMBA, although for R-(+)equol there was a trend to delaying tumor formation. In summary, early exposure to equol was not chemopreventive, but neither did it increase tumor formation in response to DMBA, suggesting exposure in early life does not influence breast cancer risk.

Clinical, molecular and epidemiological description of a cluster of community-associated methicillin-resistant Staphylococcus aureus isolates from injecting drug users with bacteraemia.

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is an increasing problem, predominantly in previously healthy individuals including notable risk groups such as the homeless, those who play close-contact sports, military personnel, men who have sex with men (MSM) and injecting drug users (IDUs). Over a 5-month period, four IDUs were admitted to Addenbrooke's Hospital, Cambridge, UK, with MRSA bacteraemia. All four patients presented with complex clinical features, with more than one focus of infection, and were linked epidemiologically. The atypical antibiogram of the MRSA isolates (ciprofloxacin-susceptible) prompted further characterization, both phenotypically (antibiotic resistance typing; phage typing) and genotypically (detection of toxin genes by PCR; pulsed-field gel electrophoresis (PFGE); Staphylococcal chromosome cassette (SCC) mec typing; multi-locus sequence typing (MLST)). All four isolates had similar antibiograms, were Panton-Valentine Leucocidin (PVL) toxin gene-negative, harboured SCCmec type IV and were closely related as shown by phage typing and PFGE. These isolates were representatives of a community-associated clone, ST1-MRSA-IV, known to be circulating in IDUs in the UK since 2001. This paper presents a detailed description of the clinical, microbiological and epidemiological features of a series of CA-MRSA bacteraemias in IDUs in the UK.

Investigation and management of an outbreak of multidrug-carbapenem-resistant Acinetobacter baumannii in Cambridge, UK.

Multidrug-resistant Acinetobacter baumannii resistant to carbapenems (MRAB-C) has become endemic in many hospitals in the UK. We describe an outbreak of MRAB-C that occurred on two intensive care units using ORION criteria (Outbreak Reports and Intervention studies Of Nosocomial infection). All patients colonised or infected with MRAB-C were included. Enhanced infection control precautions were introduced in Phase 1 of the outbreak. The adult neurosciences critical care unit (NCCU) was partially closed in Phase 2 and strict patient segregation, barrier nursing and screening thrice weekly was introduced. When control was achieved, NCCU was reopened (Phase 3) with post-discharge steam cleaning and monthly cleaning of extract and supply vents. There were 19 cases, 16 on NCCU and three on the general intensive care unit (ICU). Mean age was 52 years, with six cases being female. All patients were mechanically ventilated and ten had either an extraventricular drain or intracranial pressure monitoring device in place. Four patients developed a bacteraemia, with one further case of ventriculitis. Nine patients had no clinical evidence of infection and four were identified initially on screening. Ten patients were treated; there were eight deaths. Environmental samples showed heavy contamination throughout NCCU. MRAB-C affects critically ill patients and is associated with high mortality. This outbreak was controlled by early involvement of management, patient segregation, screening of patients and the environment, and increased hand hygiene environmental cleaning and clinical vigilance. A multidisciplinary approach to outbreak control is mandatory.

Value of CT-guided biopsy in the diagnosis of septic discitis.

AIM: To determine the role of CT-guided biopsy in the management of cases of infective discitis. METHODS: Data were examined from a retrospective case series of CT-guided biopsies for the 5-year period ending June 2006. RESULTS: 98 CT-guided biopsies were performed in the study period on 103 patients. Malignancy was diagnosed in 49 episodes. Discitis and paravertebral abscess accounted for 27 cases. Culture was positive in nine of 25 (36%) samples received by the microbiology laboratory. Staphylococcus aureus (four cases) and Mycobacterium tuberculosis (three cases) were the most frequent organisms isolated, followed by group G streptococci and coagulase-negative staphylococci (one case each). Blood cultures were diagnostic in a further nine patients. The main reason for a negative culture was prior antimicrobial therapy. The biopsy changed management in 9/25 (36%) of cases. There were no reported adverse events. CONCLUSION: Septic discitis is a serious condition with a wide variety of infective causes. CT-guided biopsy is a useful tool when the diagnosis of infectious spinal infection is considered in terms of commencing and targeting therapy, and it is a safe and well-tolerated procedure.