Infection prevention and control in ultrasound - best practice recommendations from the European Society of Radiology Ultrasound Working Group.

OBJECTIVES: The objective of these recommendations is to highlight the importance of infection prevention and control in ultrasound (US), including diagnostic and interventional settings. METHODS: Review of available publications and discussion within a multidisciplinary group consistent of radiologists and microbiologists, in consultation with European patient and industry representatives. RECOMMENDATIONS: Good basic hygiene standards are essential. All US equipment must be approved prior to first use, including hand held devices. Any equipment in direct patient contact must be cleaned and disinfected prior to first use and after every examination. Regular deep cleaning of the entire US machine and environment should be undertaken. Faulty transducers should not be used. As outlined in presented flowcharts, low level disinfection is sufficient for standard US on intact skin. For all other minor and major interventional procedures as well as all endo-cavity US, high level disinfection is mandatory. Dedicated transducer covers must be used when transducers are in contact with mucous membranes or body fluids and sterile gel should be used inside and outside covers. CONCLUSIONS: Good standards of basic hygiene and thorough decontamination of all US equipment as well as appropriate use of US gel and transducer covers are essential to keep patients safe. MAIN MESSAGES: • Transducers must be cleaned/disinfected before first use and after every examination. • Low level disinfection is sufficient for standard US on intact skin. • High level disinfection is mandatory for endo-cavity US and all interventions. • Dedicated transducer covers must be used for endo-cavity US and all interventions. • Sterile gel should be used for all endo-cavity US and all interventions.

In the era of the 24 h laboratory, does communicating Gram stain results from blood cultures flagging positive outside of conventional working hours alter patient management?

AIMS: As laboratories move towards 24 h a day working patterns, we aim to evaluate if expediting the availability of provisional blood culture results outside of normal working hours would derive clinical benefit. METHODS: 116 blood cultures flagging positive outside of conventional working hours (20:00-09:00) were studied. In each case, medical records were reviewed and cases discussed with clinicians to determine if earlier communication of results would have altered management and affected the outcome. RESULTS: Organisms were seen in 102/116 blood cultures. In total, 76/82 (92.7%) patients with cultures deemed to be significant were on an antibiotic. The isolate was sensitive to the prescribed antibiotic in 56/74 (76%) cases. Input from a microbiologist is likely to have altered management in 14 (13.7%) cases, but unlikely to have affected any outcomes. CONCLUSIONS: We found no compelling evidence that expediting the availability of Gram stain results from positive blood cultures alone improves patient outcome.

Emerging clinical role of pivmecillinam in the treatment of urinary tract infection in the context of multidrug-resistant bacteria.

The continuing spread of resistant Gram-negative bacteria is a therapeutic challenge and prudent use of antimicrobials is therefore essential. Urinary tract infections (UTIs), usually due to Gram-negative bacteria, are among the most common infections seen in the community. Moreover, bacterial strains producing extended-spectrum ß-lactamases (ESBLs) that are resistant not only to cephalosporins and penicillins, but also to fluoroquinolones and trimethoprim, are becoming more prevalent in the community. This means that oral antibiotic options to treat these infections are limited. The discovery of new drugs to tackle these problems has been difficult and slow paced; it is therefore timely to 'rediscover' the current antibiotics we have available in our clinical formulary, to determine how best they can be used. Pivmecillinam is an oral antibiotic with excellent clinical efficacy in the treatment of uncomplicated UTIs. It has been used extensively in Nordic countries with few problems, but, despite this, it is not widely used in other countries. There is emerging in vitro and in vivo evidence of its activity against ESBL-producing organisms and its synergistic potential with ß-lactamase inhibitors. Pivmecillinam is well tolerated with a low side-effect profile. Pivmecillinam also has a minimal effect on the intestinal and vaginal flora of the host; thus, there is a lower rate of selection of resistant bacteria, vaginal candidiasis and, of note, Clostridium difficile.

The genus Dietzia: a new home for some known and emerging opportunist pathogens.

The genus Dietzia has only been established fairly recently. The Gram morphology and colony appearance of the species of this genus is remarkably similar to Rhodococcus equi. In the absence of simple, accurate methods for their identification, Dietzia spp. might have been misidentified as a Rhodococcus spp. and/or considered to be contaminants only. This MiniReview is designed to summarize current evidence on the clinical significance of Dietzia species, to consider their potential role as human pathogens, and to outline approaches that can be used to accurately classify and identify members of the genus, with the overall aim of alerting the medical microbiological community to a little known genus that contains clinically significant organisms.

Laboratory diagnosis of endophthalmitis: comparison of microbiology and molecular methods in the European Society of Cataract & Refractive Surgeons multicenter study and susceptibility testing.

PURPOSE: To investigate and compare the use of molecular biology with the use of traditional Gram stain and organism culture for the laboratory diagnosis of postoperative endophthalmitis. SETTING: Twenty-four ophthalmology units together with 9 microbiology laboratories and 2 European reference molecular biology laboratories. METHODS: A prospective randomized partially masked multicenter cataract surgery study recruited 16 603 patients. This resulted in 29 cases of presumed postoperative endophthalmitis. Gram stain and culture were performed in the local laboratory according to agreed protocols. Samples of aqueous and/or vitreous were transported to the first referenced molecular biology laboratory (Regensburg, Germany) for polymerase chain reaction (PCR) testing, and an extracted aliquot of DNA was then referred to the second laboratory (Alicante, Spain) for PCR. RESULTS: Of the 29 who presented with presumed postoperative endophthalmitis, 20 were classified as proven infective endophthalmitis with positive Gram stain, culture, or PCR. Fourteen patients were culture-positive; all but 1 of these was also positive by PCR. Six patients were positive by PCR but negative by Gram stain or culture. Nine patients were negative by both microbiology and PCR testing. CONCLUSIONS: Use of molecular biology technique increased the laboratory rate of identifying the pathogen by 20%, confirming the technique is very useful for the endophthalmitis specimen. Samples of both aqueous and vitreous should be collected and stored at -20 degrees C for PCR at the time of the diagnostic taps.

Dietzia papillomatosis sp. nov., a novel actinomycete isolated from the skin of an immunocompetent patient with confluent and reticulated papillomatosis.

An actinomycete isolated from an immunocompetent patient suffering from confluent and reticulated papillomatosis was characterized using a polyphasic taxonomic approach. The organism had chemotaxonomic and morphological properties that were consistent with its assignment to the genus Dietzia and it formed a distinct phyletic line within the Dietzia 16S rRNA gene tree. It shared a 16S rRNA gene sequence similarity of 98.3% with its nearest neighbour, the type strain of Dietzia cinnamea, and could be distinguished from the type strains of all Dietzia species using a combination of phenotypic properties. It is apparent from genotypic and phenotypic data that the organism represents a novel species in the genus Dietzia. The name proposed for this taxon is Dietzia papillomatosis; the type strain is N 1280(T) (=DSM 44961(T)=NCIMB 14145(T)).

The use of erythromycin as a gastrointestinal prokinetic agent in adult critical care: benefits versus risks.

Erythromycin A, the first macrolide, was introduced in the 1950s and after years of clinical experience it still remains a commonly relied upon antibiotic. In the past, pharmacodynamic characteristics of macrolides beyond antimicrobial action such as anti-inflammatory and immune-modulating properties have been of scientific and clinical interest. The function of erythromycin as a prokinetic agent has also been investigated for a range of gastrointestinal motility disorders and more recently within the context of critically ill patients. Prokinetic agents are drugs that increase contractile force and accelerate intraluminal transit. Whilst the anti-inflammatory action may be a desirable side effect to its antibiotic action, using erythromycin A merely for its prokinetic effect alone raises the concern about promoting emergence of macrolide resistance. The objectives of this review article are: (i) to briefly summarize the modes and epidemiology of macrolide resistance, particularly in respect to that found in the Streptococcus species (a potential reservoir for the dissemination of macrolide resistance on the critical care unit); (ii) to discuss in this context the evidence for conditions promoting bacterial resistance against macrolides; and (iii) to assess the potential clinical benefit of using erythromycin A as a prokinetic versus the risks of promoting emergence of macrolide resistance in the clinical setting. We conclude, that in view of the growing weight of evidence demonstrating the potential epidemiological impact of the increased use of macrolides upon the spread of resistance, versus a lack of sufficient and convincing evidence that erythromycin A is a superior prokinetic agent to potential alternatives in the critically ill patient population, at this stage we do not advocate the use of erythromycin A as a prokinetic agent in critically ill patients unless they have failed all other treatment for impaired gastrointestinal dysmotility and are intolerant of metoclopramide. Further large and methodologically robust studies are needed to ascertain the effectiveness of erythromycin A and other alternative agents in the critically ill.

Toxic megacolon complicating Escherichia coli O157 infection.

Toxic megacolon is a well known complication in inflammatory bowel disease such as ulcerative colitis or Crohn's disease. The development of toxic megacolon as a complication of infectious colitis is rare. However it is recognised as a complication of enteric infections caused by Clostridium difficile, Campylobacter jejuni, Shigella, Salmonella species, Cytomegalovirus and amoebae. We describe a case of necrotising haemorrhagic ileo-colitis in a previously fit and healthy young adult female caused by Escherichia coli O157 where toxic megacolon developed as a complication along with hemolytic uremic syndrome (HUS).