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Aims: We describe the investigation and control of a nosocomial outbreak of Sequence Type (ST) 22 MRSA containing the Panton–Valentine leucocidin (PVL) toxin in an acute multispecialty surgical ward at University Hospital Birmingham NHS Foundation Trust.Methods: A patient was classed as acquiring methicillin-resistant Staphylococcus aureus(MRSA) if they had a negative admission screen and then had MRSA isolated from a subsequent screen or clinical specimen. Spa typing and pulsed field gel electrophoresis (PFGE) was undertaken to confirm MRSA acquisitions.Findings: The Infection Prevention and Control Team were alerted to the possibility of an outbreak when two patients acquired MRSA while being on the same ward. In total, five patients were involved in the outbreak where four patients acquired the PVL-MRSA clone from an index patient due to inadequate infection control practice. Two patients who acquired the strain developed a bloodstream infection. Infection control measures included decolonisation of affected patients, screening of all patients on the ward, environmental sampling and enhanced cleaning.Discussion: Our study highlights the potential risk of spread and pathogenicity of this clone in the healthcare setting. Spa typing and PFGE assisted with confirmation of the outbreak and implementation of infection control measures. In outbreaks, microbiological typing should be undertaken as a matter of course as without specialist typing identification of the described outbreak would have been delayed.

•Reactive oxygen species (ROS) delivered by engineered honey or gel.•Novel antimicrobial with activity against all bacteria as well as antifungal and antiviral activity.•Topical treatment with antibiofilm activity.•Therapeutic implications for wound healing and possibly mucosal infection in respiratory and urinary tract.•Topical and local applications but could be applied to internal mucosal structures.

Objective.The study aimed to examine the presence of methicillin-resistant Staphylococcus aureus(MRSA) in the environment and its relationship to patients' acquisition of MRSA.Design.A prospective study was conducted in a 9-bed intensive care unit for 14 months. At every environmental screening, samples were obtained from the same 4 sites in each bed space. Patients were screened at admission and then 3 times weekly. All environmental and patient strains were typed using pulsed-field gel electrophoresis.Results.MRSA was isolated from the environment at every environmental screening, when both small and large numbers of patients were colonized. Detailed epidemiological typing of 250 environmental and 139 patient isolates revealed 14 different pulsed-field gel electrophoresis profiles, with variants of EMRSA-15 being the predominant type. On only 20 (35.7%) of 56 occasions were the strains isolated from the patients and the strains isolated from their immediate environment indistinguishable. There was strong evidence to suggest that 3 of 26 patients who acquired MRSA while in the intensive care unit acquired MRSA from the environment.Conclusions.This study reveals widespread contamination of the hospital environment with MRSA, highlights the complexities of the problem of contamination, and confirms the need for more-effective cleaning of the hospital environment to eliminate MRSA.

The aim of the study was to test the following hypotheses: (i) that endotoxin injected 40 min prior to death can be detected in rat organs post mortem and (ii) that endotoxin levels do not change with increasing time post mortem. Rats were injected with or without endotoxin in buffered saline, 40 min prior to being killed. Endotoxin levels in rat organs were assessed using a Limulusamoebocyte assay. The effect of storage time post mortem was assessed by following various storage regimes at 25°C and 8°C. Significant differences (P=<0.001) in endotoxin levels of all samples tested were found between rats injected with and without endotoxin. A significant increase in detectable endotoxin was observed between 0 h and 6 h post mortem in rats injected with or without endotoxin. No difference in detectable endotoxin levels in the kidney, liver and spleen was observed from 30 h to 102 h post mortem in rats injected with or without endotoxin. In rats injected with endotoxin, detectable endotoxin levels in the heart were raised between 0 h and 6 h, 6 h and 54 h, and 30 h and 78 h. Endotoxin injected into rats 40 min prior to death can be detected post mortem. For rats injected with saline or endotoxin prior to death levels in the kidney, liver and spleen were not affected by storage at 8°C for 30–102 h, after initial storage at room temperature for 6 h. Levels of endotoxin detected in the hearts of rats injected with saline were not affected by storage up to 102 h. In rats injected with endotoxin prior to death, detectable levels in the heart were significantly affected by increasing time in storage.

Seventeen of 60 cases of pneumococcal bacteremia in children at Baragwanath Hospital in 1983 were caused by strains not fully susceptible to penicillin G. Eight strains had minimal inhibitory concentrations of >1 µg/ml and five were resistant to four or more antimicrobial agents. Only three isolates were resistant to chloramphenicol. Antibiotic-resistant strains occurred in younger children with a mean age of 13.1 months compared with a mean age of 31.6 months in children with susceptible strains (P< 0.01). Underlying conditions, including nutritional status, did not correlate with antibiotic resistance of isolates from blood. Some of the resistant strains were apparently community-acquired. Of 3379 nasopharyngeal swabs taken from hospitalized children 829 yielded pneuoiococei and 408 of these carrier strains were either relatively or fully resistant to penicillin while 241 were resistant to four or more antibiotics. Multiply resistant strains from patients and carriers belonged to serovars 6A, 6B and 19A.

We investigated 117 patients undergoing percutaneous nephrolithotomy, percutaneous nephrostomy, ureterorenoscopy, the push-back or push-bang procedure for ureteral stones, Double-J**Medical Engineering Corp., New York, New York.ureteral stenting plus extracorporeal shock wave lithotripsy (ESWL††Dornier Medical Systems, Inc., Marietta, Georgia.), ESWL alone or cystoscopy. Blood samples obtained before, during and 1 hour after the procedure were cultured and assayed for endotoxin and tumor necrosis factor. Also, culture was done of the urine preoperatively and postoperatively, and the stones when they could be retrieved. There was a temporal relationship among bacteremia, endotoxemia and elevation of tumor necrosis factor. An unexpected finding was preoperative endotoxemia in a significant number of patients with stones. Risk factors noted for postoperative bacteremia, endotoxemia and/or elevation of tumor necrosis factor included preoperative endotoxin level, type of procedure, presence of preoperative bacteriuria and pyuria. With respect to the procedure the risk was greatest after the push-back method and least after cystoscopy (push-back method greater than percutaneous nephrolithotomy/percutaneous nephrostomy greater than Double-J stenting plus ESWL greater than ureterorenoscopy greater than ESWL greater than cystoscopy). If the risk factors are measured preoperatively it may be possible to identify the risk of postoperative bacteremia/endotoxemia and, therefore, septic shock postoperatively. Our patients appear to be a good clinical model to investigate the problems related to septicemia.

ABSTRACTWe evaluated toxigenic Clostridium difficiledetection by a lateral flow assay for antigen and toxin, an enzyme immunoassay, and two commercial PCR methods. Compared to the cell cytotoxicity neutralization assay and toxigenic culture, both toxin detection methods lacked sensitivity. PCR following combined antigen and toxin detection provided the most useful diagnostic information.

ABSTRACTStaphylococcal interspersed repeat unit typing has previously been shown to have the ability to discriminate between epidemic methicillin-resistant Staphylococcus aureusstrains in the United Kingdom. The current study illustrates its ability to distinguish between strains within an endemic setting thereby providing a rapid transportable typing method for the identification of transmission events.

The interface between implanted devices and their host tissue is complex and is often optimized for maximal integration and cell adhesion. However, this also gives a surface suitable for bacterial colonization. We have developed a novel method of modifying the surface at the material–tissue interface with an antimicrobial peptide (AMP) coating to allow cell attachment while inhibiting bacterial colonization. The technology reported here is a dual AMP coating. The dual coating consists of AMPs covalently bonded to the hydroxyapatite surface, followed by deposition of electrostatically bound AMPs. The dual approach gives an efficacious coating which is stable for over 12 months and can prevent colonization of the surface by both Gram-positive and Gram-negative bacteria.

Although infectious diseases have been one of the major problems affecting mankind throughout history, during the latter part of the 20th century an air of complacency seemed to emerge. It was felt that the combination of improved sanitation, availability of vaccines, and the development of powerful broad spectrum antimicrobials would allow us to permanently conquer the threats posed by serious life-threatening infections. Recent events have shown that these optimistic predictions are unlikely to be achievable, and in recent years major infectious disease scares both nationally and internationally have repeatedly hit the headlines.

The aim of the study was to test the following hypotheses: (i) that endotoxin injected 40 min prior to death can be detected in rat organs post mortem and (ii) that endotoxin levels do not change with increasing time post mortem. Rats were injected with or without endotoxin in buffered saline, 40 min prior to being killed. Endotoxin levels in rat organs were assessed using a Limulus amoebocyte assay. The effect of storage time post mortem was assessed by following various storage regimes at 25°C and 8°C. Significant differences (P=<0.001) in endotoxin levels of all samples tested were found between rats injected with and without endotoxin. A significant increase in detectable endotoxin was observed between 0 h and 6 h post mortem in rats injected with or without endotoxin. No difference in detectable endotoxin levels in the kidney, liver and spleen was observed from 30 h to 102 h post mortem in rats injected with or without endotoxin. In rats injected with endotoxin, detectable endotoxin levels in the heart were raised between 0 h and 6 h, 6 h and 54 h, and 30 h and 78 h. Endotoxin injected into rats 40 min prior to death can be detected post mortem. For rats injected with saline or endotoxin prior to death levels in the kidney, liver and spleen were not affected by storage at 8°C for 30–102 h, after initial storage at room temperature for 6 h. Levels of endotoxin detected in the hearts of rats injected with saline were not affected by storage up to 102 h. In rats injected with endotoxin prior to death, detectable levels in the heart were significantly affected by increasing time in storage.

Penicillin has long been recognized as the antibiotic of choice for treatment of meningococcal infections, but clinicians have recently become concerned about the susceptibility of meningococci to penicillin and other antibiotics used in the management of meningococcal disease. Strains relatively resistant to penicillin (minimum inhibitory concentrations ranging from 0.1 mg/L to 1.28 mg/L) have been reported from a large number of countries, although the frequency with which such isolates are found varies widely. The mechanism of relative resistance to penicillin involves, at least in part, the production of altered forms of one of the penicillin-binding proteins. Although treatment with penicillin is still effective against these relatively resistant strains, there is evidence that low-dose treatment regimens can fail. ß-lactamase production in meningococci is extremely rare but has been reported, and this finding is of great concern. Resistance to sulfonamides and rifampin is of particular concern in regard to the management of contacts of patients with meningococcal disease.

Amphotericin B colloidal dispersion (ABCD), a novel formulation of amphotericin B and cholesteryl sulfate in a 1:1 ratio, was developed to reduce the toxicity of amphotericin B yet retain its antifungal efficacy. In an open-label trial, ABCD at dosages as high as 6 mg/(kg·d) was administered to 168 patients with documented or presumed systemic mycoses. All patients had responded incompletely to at least 7 days' treatment with conventional amphotericin B (CAB), had experienced CAB-induced nephrotoxic effects, had preexisting renal impairment, or had experienced other CABrelated, treatment-limiting toxic effects. The clinical response to ABCD could be evaluated in 97 patients. Complete clinical response or improvement was noted in 48 (49%) of them after a mean treatment duration of 18.5 days. All 168 enrolled patients were evaluated with regard to safety of the treatment. Even at daily doses as high as 6 mglkg, and mean and median cumulative doses of 4.0 g and 2.4 g, respectively, ABCD had little renal toxicity: the mean change in serum level of creatinine from baseline to final value was −0.02 mg/dL. Hypokalemia developed in eight patients (5%). This study provides preliminary evidence that ABCD is effective in treating invasive mycoses and lacks the dose-limiting nephrotoxicity of CAB.