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Salmonella enterica serotype Bredeney has emerged as the third most commonly identified serotype among human clinical isolates referred to the Irish National Salmonella Reference Laboratory in the years 1998 to 2000. A collection of 112 isolates of S. enterica serotype Bredeney collected during the period 1995 to 1999 from animal, food, and human sources from both Ireland and Northern Ireland were studied. Antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), and DNA amplification fingerprinting (DAF) were performed on all isolates. Plasmid profiles were examined on a subset of 33 isolates. A high proportion (74%) of isolates were susceptible to all antimicrobial agents tested. Resistance to both sulfonamide and trimethoprim was observed in 21% of isolates, and resistance to multiple (five) antimicrobial agents was observed in a single isolate (0.9%). Eight different PFGE patterns were obtained, with 87% of isolates grouping as PFGE type A. PFGE type A was predominant in animals, food, and humans. There was good overall concordance between the groups identified by PFGE and DAF. Overall results indicate that most S. enterica serotype Bredeney isolates in Ireland and Northern Ireland from animal and human sources are clonally related.

Resistance of bacteria to antibiotics is an increasing problem in many countries. Accurate locally relevant information is essential for detection and control of emerging resistance and to facilitate choice of empirical antibiotic therapy in the immediate management of seriously ill patients. We have determined the minimum inhibitory concentration of piperacillin/tazobactam for 97 strains of bacteria (55 Enterobacteriaceae, 13 non-fermentative Gram-negative bacilli, 22 Staphylococcus aureus, 6 Enterococcus faecalis and 1 Bacillus cereus) isolated from blood cultures and compared its activity to that of amoxycillin, co-amoxiclav, cephalothin, cefotaxime, ceftazidime, ciprofloxacin, gentamicin, piperacillin, cefotaxime. The strains were consecutive non-fastidious isolates with the following qualifications: coagulase negative staphylococci and diphtheroids were excluded and the number of Staphylococcus aureus isolates was limited to 12 methicillin-resistant and 10 methicillin-sensitive strains. Multiple isolates of the same species from individual patients were not included. The minimum inhibition concentrations of methicillin, penicillin, teichoplanin and vancomycin were also determined for specific groups of organisms. MICs were determined by the Etest method (AB Biodisk, Solna, Sweden) on Mueller Hinton agar. The MICs of appropriate American Type Culture Collection control strains were determined. Based on the interpretative criteria of the National Committee for Clinical Laboratory Standards (USA), 87 per cent of Gram-negative bacilli were susceptible to piperacillin/tazobactam compared with amoxycillin 26 per cent, cephalothin 35 per cent, co-amoxiclav 54 per cent, piperacillin 56 per cent, cefotaxime 69 per cent, ceftazidime 84 per cent, gentamicin 85 per cent and ciprofloxacin 91 per cent. Of all isolates 75 per cent were sensitive to piperacillin/tazobactam, compared with amoxycillin 22 per cent, cephalothin 35 per cent, piperacillin 41 per cent, co-amoxiclav 52 per cent, cefotaxime 59 per cent, ceftazidime 60 per cent, gentamicin 74 per cent and ciprofloxacin 77 per cent. Two isolates (1 E. coli and 1 Klebsiella pneumoniae) with antibiograms consistent with the relatively new resistance phenomenon of extended spectrum beta-lactamase production were identified. The spectrum of activity of piperacillin-tazobactam for empirical antibiotic therapy is significantly greater than that of piperacillin alone and is similar to that of ciprofloxacin and gentamicin.

We describe a case of primary cutaneous mucormycosis (zygomycosis) in a patient with idiopathic aplastic anemia which responded to surgical debridement and therapy with liposomal amphotericin B. The tissue removed at surgery showed dense infiltration with fungal hyphae on histopathological examination. Primary cultures of tissue on solid media were negative, but Absidia corymbifera was isolated from unprocessed tissue placed in brain heart infusion broth.

Lyme disease is a multisystem infectious disease, endemic in parts of Europe, including the West of Ireland. Neurological manifestions (neuroborreliosis) are variable. Presenting neurological syndromes include meningitis, cranial neuropathies, myeloradiculitis and mononeuritis multiplex. A lack of specificity in serological diagnosis may add to diagnostic confusion. We reviewed thirty cases of acute Lyme disease in the West of Ireland and found neurological syndromes in 15 (50%), with painful radiculopathy (12 patients; 80%) and cranial neuropathy (7 patients; 46%) occurring frequently. Neuroborreliosis needs to be considered in the differential diagnosis of these neurological syndromes in the appropriate clinical context.

In mid-February 2007, there was a small rise in the number of laboratory-notified cases of cryptosporidiosis in the city and county of Galway, Ireland in comparison to February 2006.

An institutional outbreak of gastroenteritis provided an opportunity to investigate further the isolates of salmonella typhimurium by pulsed-field gel electrophoresis (PFGE). Three phage types were identified. Antibiograms identified two types and two distinct patterns were found in PFGE. If phage typing alone is used for epidemiological study of strains, it is possible that an association between strains may be missed.

Knowledge of antimicrobial resistance patterns in E. coli, the predominant pathogen associated with urinary tract infection (UTI) is important as a guide in selecting empirical antimicrobial therapyTo describe the antimicrobial susceptibility of E. coli associated with UTI in a region in the West of Ireland.A collection of 934 E. coli isolates associated with UTI were tested for susceptibility to a panel of antimicrobial agents by the disc diffusion method of the National Committee for Clinical Laboratory Standards.More than 50% of E. coli were resistant to ampicillin, more than 40% resistant to sulphonamide and more than 30% resistant to trimethoprim. From 7.9% (community) to 12.5% (hospital) are resistant to co-amoxiclav with approximately 20% of isolates of intermediate susceptibility. In general practice most E. coli remain susceptible to nitrofurantoin (96.7%), nalidixic acid (93.9%) and ciprofloxacin (94.7%). For all agents rates of resistance were higher in hospital as compared with general practice isolates. Three isolates with the phenotype of Extended Spectrum Beta-lactamase (ESBL) resistance were detected.Ampicillin/amoxicillin are not suitable for empiric therapy of UTI in general practice or hospital patients in this region. There is doubt as to the role of trimethorpim or co-trimoxazole for empiric therapy of UTI. Nitrofurantoin, nalidixic acid and ciprofloxacin are active against the great majority of UTI associated E. coli.

Resistance or susceptibility of Salmonella enterica to streptomycin is widely used as an epidemiological marker. However, there is no clear consensus on the interpretation of streptomycin susceptibility test results. Comparison of results obtained with the Clinical and Laboratory Standards Institute (CLSI) disk diffusion method, the minimum inhibitory concentration (MIC) determined by Etest and streptomycin resistance genotype for 90 isolates of S. enterica serovar Typhimurium suggests that appropriate interpretive criteria for MIC results are susceptible ator=8 mg/L and resistant ator=16 mg/L. For CLSI disk diffusion, we propose susceptible at a zone diameteror=13 mm and resistant ator=10 mm.

Salmonella enterica serovar Typhimurium is frequently isolated from humans and animals. Phage typing is historically the first-line reference typing technique in Europe. It is rapid and convenient for laboratories with appropriate training and experience, and costs of consumables are low. Phage typing and pulsed-field gel electrophoresis (PFGE) were performed on 503 isolates of serovar Typhimurium. Twenty-nine phage types and 53 PFGE patterns were observed. Most isolates of phage types DT104, DT104b, and U310 are not distinguishable from other members of their phage type by PFGE. By contrast, PFGE of isolates of phage types DT193 and U302 shows great heterogeneity. Analysis of experience with PFGE and phage typing can facilitate the selective application of PFGE to maximize the yield of epidemiologically relevant additional information while controlling costs.

We have observed a high incidence of isolated nalidixic acid resistance in Salmonella enterica serovar Enteritidis isolates in Ireland, particularly isolates of phage type 1 (PT1). A group of nalidixic acid-resistant ( n = 22) and nalidixic acid-susceptible ( n = 28) isolates of serovar Enteritidis from multiple sites in Ireland were selected. Isolates were typed by pulsed-field gel electrophoresis (PFGE) with XbaI, and the MICs for nalidixic acid and ciprofloxacin were determined. Mutations associated with nalidixic acid resistance in clinical isolates and laboratory mutants of serovar Enteritidis and 32 nalidixic acid-resistant isolates of 15 other salmonella serovars were identified. PFGE had limited discriminatory power. A specific point mutation (G246T) associated with amino acid substitution Asp87Tyr in the quinolone resistance determining region of the gyrA gene accounted for 95% of all mutations in serovar Enteritidis and for all mutations in PT1 isolates. Greater diversity of mutations was observed among all non-Enteritidis salmonella serovars studied. Rates of nalidixic acid resistance in serovar Enteritidis may predominantly reflect clonal expansion after infrequent mutation or selection events.

Between 1998 and 2003, 5,161 isolates (3,182 human) of Salmonella enterica were received by the National Salmonella Reference Laboratory of Ireland. Serotyping, antimicrobial susceptibility testing and phage typing were performed by standard methods. The number of isolates of S. enterica serovar Typhimurium decreased from 579 (80%) in 1998 to 208 (19%) in 2003, while S. enterica serovar Enteritidis increased from 59 (8%) in 1998 to 219 (20%) in 2003. Definitive (DT) phage types 104 and DT104b accounted for a declining proportion of all Salmonella Typhimurium isolates (from n = 523 [90%] in 1998 to 126 [60%] in 2003). Numbers of Salmonella Enteritidis phage type 4 declined from 50 (85%) in 1998 to 59 (27%) in 2003. Twenty-eight isolates of typhoidal Salmonella were received with a history of recent travel in 17 cases. Resistance to multiple (four or more) antimicrobial agents was related to serotype and, where applicable, phage type, and was common in Salmonella Typhimurium. Salmonella Typhimurium predominated among isolates from cattle and pigs (n = 213 [58%]), while Salmonella Livingstone (n = 327) and S. Kentucky (n = 227) were predominant in isolates from poultry (total n = 554 [43%]). This paper discusses trends, and their implications, in Irish salmonella isolates since the establishment of the Reference Laboratory.

During investigation of an episode of Salmonella enterica serovar Kedougou contamination of mushrooms, multiple closely related isolates were obtained from mushrooms and mushroom-growing materials. Contamination apparently originated from sugar beet lime, an alkaline material used in mushroom growing. No associated cases of human infection were detected.

Shigella sonnei is a significant cause of gastroenteritis in both developing and industrialized countries. Definition of the diversity and antimicrobial susceptibility of S. sonnei isolates may be helpful in the management of individual cases and outbreaks. Antimicrobial susceptibility testing and pulsed-field gel electrophoresis (PFGE) were performed with 67 isolates of S. sonnei predominantly ( n = 59) from three counties in the west of Ireland. Phage typing ( n = 17), plasmid profiling ( n = 28), and integron analysis ( n = 24) were performed with subsets of strains. PFGE typing permitted recognition of two major clusters: PFGE type A ( n = 53) and PFGE type B ( n = 14). PFGE type A was associated with resistance to ampicillin, streptomycin, and sulfonamides (51 of 53 isolates), and those that were phage typed ( n = 6) were phage type 3. PFGE type B was associated with resistance to streptomycin, sulfonamides, tetracycline, and trimethoprim (11 of 14 isolates) and phage type 6 (9 of 11 isolates). Fifteen different plasmid profiles were identified among the 28 isolates analyzed. A class 2 integron was present in all 14 PFGE type B isolates. One of these isolates also contained a class 1 integron and showed a unique variant of the PFGE type B pattern. Sequence analysis of the gene cassette structures contained within these integrons identified distinct open reading frames that encoded determinants of resistance to trimethoprim, streptomycin, and streptothricin. Our data demonstrate two predominant PFGE types among S. sonnei isolates circulating in this region. The limited diversity of the S. sonnei isolates in this region means that detection of isolates indistinguishable by PFGE and according to their antibiograms in two or more patients is not persuasive evidence of a common-source food- or waterborne outbreak. Indistinguishable plasmid profiles in addition to indistinguishable PFGE and antibiogram types may be more suggestive of an epidemiologically relevant link between cases.

Sir, We read with interest the paper by van den Bogaard and colleagues relating to the antimicrobial susceptibility of Escherichia coli isolates from poultry. Since September 2000 we have been studying the antimicrobial susceptibility of E. coli isolated as pathogens from poultry flocks in two counties in Ireland. Isolates were obtained on culture of tissues or swabs from diseased or dead animals and referred to the Department of Bacteriology, National University of Ireland, Galway, for antimicrobial susceptibility testing. The identity of the isolates as E. coli was confirmed by API20E and antimicrobial susceptibility testing was performed by the disc diffusion method of the NCCLS. Susceptibility to 13 antimicrobial agents (Table) was determined, using E. coli ATCC 25922 as control. For isolates categorized as intermediate or resistant to ciprofloxacin by initial disc diffusion susceptibility testing, the ciprofloxacin MIC was determined by Etest. A total of 209 isolates of E. coli have been examined, 171 isolates from turkeys and 38 from hens (broiler and egg layers). The percentage of isolates susceptible, intermediate and resistant to each antimicrobial agent is outlined in the Table. The ciprofloxacin MIC for the five ciprofloxacinresistant isolates was in the range 6 to 16 mg/L. Like van den Bogaard et al., we observed a trend towards higher levels of antimicrobial resistance in turkeys, in which antimicrobial use is more common. Resistance to sulphonamides, trimethoprim and nalidixic acid were more common in E. coli originating from turkeys, and ciprofloxacin resistance, albeit at a low level of 2.9%, was observed only in E. coli isolates from turkeys. Our data differ from those of van den Bogaard et al. in a number of respects. The isolates were considered pathogenic and susceptibility test methods and interpretative Correspondence Journal of Antimicrobial Chemotherapy (2001) 48, 587–595

Clostridium difficile is the principal pathogen associated with hospital-acquired acute diarrheal disease. We have evaluated the performances of six approaches for diagnosis of C. difficile -associated diarrhea (CDAD). Consecutive stool specimens ( n = 200) from 133 patients were examined by cytotoxin assay, by culture of C. difficile on cycloserine-cefoxitin-fructose agar, and by toxin detection using four rapid immunoassay systems (Oxoid Toxin A test, ImmunoCard Toxin A test, TechLab Tox A/B II test, and Premier Toxins A&B test). A diagnosis of CDAD was established for 35 (27%) patients (representing 29% of specimens). The adjusted sensitivity and specificity of the methods were, respectively, 98 and 99% for the cytotoxin assay, 54 and 99% for ImmunoCard, 50 and 98% for Oxoid, 79 and 98% for TechLab, 80 and 98% for Premier, and 57 and 100% for culture. The TechLab and Premier assays are acceptable tests for diagnosis of CDAD but are not equivalent to the cytotoxin assay.

Production of extended-spectrum-s-lactamases (ESBLs) is predominantly associated with the Enterobacteriaceae , particularly Escherichia coli and Klebsiella pneumoniae . ESBL production in Salmonella spp. was first identified in 1988 ([11][1]) and is increasing in prevalence worldwide ([3][2], [18][

Sir, Ziglam et al. have recently reported an audit of linezolid use in a hospital in Scotland for the period March 2001–September 2003. We conducted a similar audit of linezolid use in a 504 bed teaching hospital, to assess the profile of patients prescribed linezolid, clinical and microbiological indications for treatment, adherence to the licensed indications and product specifications, and documented adverse events. The hospital provides a range of surgical and medical specialties with the exceptions of orthopaedics, neurosurgery and renal medicine. The audit was conducted between October 2004 and April 2005. The hospital drugs and therapeutics committee recommends that linezolid be used in consultation with the Departments of Infectious Diseases or Microbiology; however, consultation cannot be mandated within the hospital governance system. Patients prescribed linezolid were identified through pharmacy, and the medical records for each case were reviewed. Fifty-three courses of linezolid were prescribed to 46 patients, and the clinical indications are listed in Table 1. Methicillin-resistant Staphylococcus aureus (MRSA) was the microbiological indication for 49% of the courses; vancomycinresistant enterococcus (VRE) in 4%, vancomycin-susceptible Enterococcus faecium (4%) and coagulase-negative staphylococcus were also targeted (2%). In 41% of the courses the prescription was empirical. In 55% of cases linezolid was prescribed as initial therapy for a vancomycin-susceptible organism. In 31% of cases this prescription was made without a recorded or apparent justification for favouring linezolid use over vancomycin. Of the 53 courses prescribed, 20 were initiated by the Department of Microbiology or Infectious Diseases in the intensive therapy unit, and a further three courses were initiated following consultation with these departments. Thirty courses (57%) represented autonomous prescribing decisions. The median duration of therapy was 12 days (range 1–58 days). One course of linezolid was associated with a documented adverse effect, being a reversible pancytopenia which occurred in a 65-year-old lady. Our findings present both similarities to and contrasts with those of Ziglam et al. Our audit was conducted more than a year after the study by Ziglam et al. was completed. By the time of this audit, evidence indicating that linezolid may have advantages for initial therapy for MRSA pneumonia was widely disseminated, and there was greater familiarity with linezolid among clinicians. As with the previous study, we found that MRSA is the most common microbiological indication for linezolid prescription and that major prescribing was done without consultation with Microbiology or Infectious Disease. In contrast with Ziglam et al., we found that linezolid was used in a high proportion of cases (42% compared with 6%) without apparent microbiological indication. Impaired renal function or poor venous access was an indication for linezolid use in 34% of cases in the Ziglam study but only for 6% of the courses prescribed in this study. Thrombocytopenia was noted in 8% of the courses in the earlier study but in only 2% in this study. Our audit indicates relatively frequent use of linezolid without microbiological justification and its use as first line therapy for organisms/infections that could be expected to respond to vancomycin. This pattern of use may reflect growing familiarity with linezolid among clinicians. Anecdotal experience suggests that the convenience of administration of linezolid and its low toxicity, together with persistent fears of glycopeptide toxicity, are major factors in driving linezolid prescription. Linezolid is a valuable but expensive agent for treatment of resistant Gram-positive agents. Given that emergence of linezolid resistance during treatment has been described previously on a number of occasions, efforts to limit the use of this agent are appropriate. Mandatory consultation with infection specialists with regard to linezolid prescription is not enforceable in many healthcare governance systems, and in such settings reliance must be placed on educational activities, including audits such as this and feedback of findings. Table 1. Clinical indications for use of linezolid during a 6 month audit in a teaching hospital

During the period from August 1989 to October 1990, 93 patients living in the West of Ireland were screened for Hepatitis C antibodies (Anti HVC) using a commercially available assay. The tests were performed because of abnormal liver function tests (LFTs) or clinical suspicion of Hepatitis C. Nine positive results were obtained (10.3%) seven of whom had a history of transfusion of blood or a blood product. The study revealed that the prevalence of anti HCV was low in patients with chronic liver diseases, in comparison to reported prevalence rates in other parts of the world and that blood transfusion was the commonest predisposing factor to acquisition of anti HCV in this area.

Dr. Alcaide and colleagues have recently reported an evaluation of the BACTEC MGIT 960 (Becton Dickinson) and MB/BacT (Organon Teknika) systems for recovery of mycobacteria from clinical specimens ([1][1]). We have recently completed a similar evaluation at the University College Hospital Galway.

Admission of patients to University College Hospital, Galway over a five month period commencing December 1989 indicates an increase in the incidence of Neisseria Meningitidis Serogroup C. Seven cases of Group C N. Meningitidishave been identified, five of them occurring over a four week period. A review of Meningococcal isolates occurring at this hospital over eleven years since 1979 shows, serogroup B as the predominant serogroup. Thirty-six isolates identified by serogrouping shows the distribution of serogroups as follows: Serogroup B 69.4%, Serogroup C 19.4%, Serogroup A 8.3%, Serogroup Z 2.7%. Serogrouping, and when available, further serotyping of meningococcal isolates is very important in order to follow epidemiological trends in the disease and to monitor the serogroups that cause outbreaks. This information can influence measures that can be taken in the prevention of spread of the disease as for example the use of vaccination as appropriate.

A review of isolates of Neisseria meningitidis and other laboratory evidence of meningococcal infection was carried out for the period 1990-1995. Thirty-three patients with evidence of meningococcal disease were identified over the six year period. Group B organisms were the most commonly identified, but an increase in Group C has occurred and is almost equal in number. Data from clinical, laboratory and public health sources should be centralized in a National Surveillance Centre.

Data from 8,717 fecal specimens indicate that primary inoculation of xylose lysine deoxycholate (XLD) agar may enhance the speed, but not the sensitivity, of isolation of Salmonella enterica over that achieved with Selenite enrichment only. Plating of Selenite broth onto both brilliant green and XLD agar offers no advantage over plating onto XLD alone.

ROUTINE laboratory examination of faeces from five infants with diarrhoea who were admitted to a Gastroenteritis Unit, failed to detect Salmonella, Shigella, Campylobacter jejuni, Yersinia enterocolitica, traditional enteropathogenis strains of E. coli, viruses or ova and parasites. Further study of Escherichia coli strains isolated from four of the children showed them to be enterotoxigenic strains, serotype 078 H12, producing both heat-labile and heat-stable enterotoxin.

Coagulase negative staphylococci are frequently isolated from clinical specimens. Staphylococcus epidermidis is the most pathogenic coagulase negative staphylococcus. In this paper, we compared the results obtained when Staphylococcus epidermidis is identi fied by a commercially available kit, the API Staph kit, and by a simple two sugar method, trehalose and maltose. Both methods concurred and we feel that the two sugar method provides an inexpensive rapid and simple means of identifying Staphylococcus epidermidis.

Summary During a period of 12 months beginning on 18 February 1985, 1246 specimens of faeces from 935 children aged 3 weeks to 12 years with acute diarrhoea of varying severity were examined for the presence of cryptosporidium oocysts. Twenty-six patients required admission to hospital; four of them needed intravenous rehydration. Predominant clinical features were diarrhoea, often watery, and vomiting. Diarrhoea varied in duration between 7–15 days. Cryptosporidium oocysts were found in specimens from 41 patients, an incidence of 4·3%. In four patients an additional enteropathogen was identified ( Campylobacter species in two and enteropathogenic Escherichia coli in two — serotypes 0126: K71 (B16) and 018C : K77 (B12)). None of the patients had recently travelled abroad. Of the children 23 were from a farming or rural background. Eight of the farms had recently had significant outbreaks of diarrhoea among calves. There was a marked seasonal variation with 27 of the cases arising between 18 February and 18 June, an incidence during this period of 8%.