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BackgroundCoagulase-negative staphylococci (CoNS) are a major cause of nosocomial blood stream infection, especially in critically ill and haematology patients. CoNS are usually multidrug-resistant and glycopeptide antibiotics have been to date considered the drugs of choice for treatment. The aim of this study was to characterize CoNS with reduced susceptibility to glycopeptides causing blood stream infection (BSI) in critically ill and haematology patients at the University Hospital Tor Vergata, Rome, Italy, in 2007.MethodsHospital microbiology records for transplant haematology and ICU were reviewed to identify CoNS with elevated MICs for glycopeptides, and isolates were matched to clinical records to determine whether the isolates caused a BSI. The isolates were tested for susceptibility to new drugs daptomicin and tigecycline and the genetic relationship was assessed using f-AFLP.ResultsOf a total of 17,418 blood cultures, 1,609 were positive for CoNS and of these, 87 (5.4%) displayed reduced susceptibility to glycopeptides. Clinical review revealed that in 13 cases (7 in haematology and 6 in ICU), CoNS with reduced susceptibility to glycopeptides were responsible for a BSI. Staphylococcus epidermidis was the causative organism in 11 instances and Staphylococcus haemolyticus in 2. The incidence of oxacillin resistance was high (77%), although all isolates remained susceptible to linezolid, daptomycin and tigecycline. Fingerprinting of CoNS identified one clonal relationship between two isolates.ConclusionMulti-resistant CoNS with reduced susceptibility to glycopeptides, although still relatively infrequent in our hospital, are emerging pathogens of clinical concern. Surveillance by antibiotyping with attention to multi-resistant profile, and warning to clinicians, is necessary.

Background: The nosocomial infections surveillance system must be strongly effective especially in highly critic areas, such as Intensive Care Units (ICU). These areas are frequently an epidemiological epicentre for transmission of multi-resistant pathogens, like Acinetobacter baumannii. As an epidemic outbreak occurs it is very important to confirm or exclude the genetic relationship among the isolates in a short time. There are several molecular typing systems used with this aim. The Repetitive sequence-based PCR (REP-PCR) has been recognized as an effective method and it was recently adapted to an automated format known as the DiversiLab system.

SUMMARY The possibility that the small intestine may represent a reservoir for Clostridium difficile was studied, using segments of human jejunum collected at necropsy. Our results (three of 100 specimens positive for C difficile culture) support the hypothesis that C difficile can be found in human jejunum and that it adheres to the normal mucosa as a resident bacterium. These findings suggest that gastrointestinal disease caused by C difficile has an endogenous origin.The possibility that the small intestine might represent a reservoir for disease caused by Clostridium dificile was suggested by Taylor et al, when they isolated C difficile from a jejunal aspirate of a patient with chronic colitis.' This hypothesis was confirmed by our experience with a case of pseudomembranous enteritis with spared colon, in which we isolated C difficile from the patient's ileum obtained atTo elucidate these findings we carried out a study to verify the rate of isolation of C difficile from human small intestine using segments of jejunum that had been obtained at necropsy. Material and methods COLLECTION OF SPECIMENSOver six months one hundred segments of proximal jejunum were collected within 48 hours from 100 patients who had died. The specimens were about 10 cm long and macroscopically free from lesions. Each segment was placed in a sterile Petri dish and immediately sent to the bacteriology laboratory.The subjects had died from different diseases, none of them had had diarrhoea or other gastrointestinal symptoms in life. The mean age was 70 years (range 52-86); 90% of the patients had received treatment with antibiotics-that is, ,B-lactam antibiotics alone, or in conjunction with aminoglycosides. PROCESSING OF THE SPECIMENSTo remove the bacteria that were not firmly attached to mucosa each segment was carefully washed with 10cc of a sterile saline solution using a vortex mixer for 10 minutes.3 This procedure was repeated three Accepted for publication 18 March 1986 861 times for each sample, changing the container and the washing liquid each time. After this the segment was stretched and the mucosa removed with a sterile Iancet; the material obtained was used to inoculate a cycloserine-cefoxitin-fructose selective agar (CCFA) plate.4 The plates were screened for colonies characteristic of C difficile; all the cultures were incubated for at least five days before being discarded. The three washings from each segment were centrifuged for 10 minutes at 5000 rpm and the sediments were used to inoculate a CCFA plate. ResultsWithin 48 hours the cultures from the mucosa were positive for C difficile in three cases. Prolonged incubation of the other samples did not yield any additional positive results. None of the centrifugated washings yielded C difficile. The ages of the culture positive patients were 63, 60, and 74 years; all of them had received treatment with antibiotics.

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