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Background Candida spp., mainly Candida albicans, are frequently responsible for complications in immunocompromised patients. There are limited data comparing recovery efficiency using simple non-selective basal broth media. Aim To compare several commercially available basal growth media to determine the medium that gave highest yeast proliferation. Method Eight commercially available non-selective basal broth culture media were evaluated for optimum recovery of clinical C. albicans and C. glabrata. They included nutrient broth (NB), nutrient broth no. 2 (NB2), Todd-Hewitt (TH) broth, tryptone soya broth (TSB), tryptone soya broth supplemented with yeast extract (0.5% w/v [TSBYE]), brain heart infusion broth supplemented with yeast extract (0.5% w/v [BHIYE]), salt meat broth (SMB) and 0.1% [w/v] peptone saline (PS). Differences in cell density were evaluated by spectrophotometrical analysis. Results TSBYE>BHIYE>TSB>TH>NB2>NB>SMB>PS for the optimum proliferation of cells in vitro. Either TSBYE or BHIYE broth may be employed as suitable basal broth media for growth of C. albicans and C. glabrata. NB should be considered the least suitable medium for routine use when others are available. Conclusion These data may be of value to laboratories setting up simple blood culture systems to detect Candida spp., particularly in developing and underdeveloped countries. [ABSTRACT FROM AUTHOR]

Aim: To determine the prevalence of Burkholderia cepacia from the environment in a regional adult cystic fibrosis (CF) care centre., Methods: Two hundred and eighty-five environmental samples were taken from inpatient and outpatient environments within the CF centre. Following a non-selective enrichment step, broths were plated onto a selective medium and B. cepacia isolates were confirmed by phenotypic tests and also genotypically by species specific 16S rRNA PCR., Results: B. cepacia was not detected from commonly shared items of equipment, staff hands, staff uniforms or toilets. In addition, the organism was not detected in toilet bowls, even in the B. cepacia unit. With regard to positive environments for B. cepacia, 4/10 (40%) of the outside surfaces and inner rims of patients' plastic disposable sputum collection containers and 4/17 (23.5%) of air from patients' rooms, following physiotherapy, were positive., Conclusions: All positive samples originated in the B. cepacia segregation area of the inpatient wards and B. cepacia was not detected in the non-cepacia area of the CF centre. Consequently, these two positive sites should therefore be treated as high risk, where organisms may be potentially transmitted from environment to patient. As there is now evidence to suggest differences in the virulence and hence clinical outcome of certain of the genomovars of this organism, this study may be important in highlighting the areas that patients who are B. cepacia positive should avoid, to minimise the risk of transmission and acquisition of this organism within the CF cepacia population. These results indicate that effective infection control procedures are required in patients' rooms following physiotherapy, for prevention of B. cepacia transmission and to avoid the transmission of different genomovar types within CF patients, who are already colonised with this pathogen.

Background: No study has compared Campylobacter isolates from a human source in Northern Ireland over an extended period of time., Aim: To investigate the clonal stability of thermophilic campylobacters isolated from acute bacterial enteritis in Northern Ireland from 1992 to 1999., Methods: Human isolates (n=272), originating from faeces, were characterised at the sub-species level using enterobacterial repetitive intergenic consensus sequence (ERIC2)--random amplification of polymorphic DNA (RAPD) typing., Results: Thirteen genotypes were identified where three types, namely ERIC A, ERIC C and ERIC I, accounted for 28.3%, 14.3% and 13.6%, respectively. There were no significant associations (p>0.05) between sex, age groupings and year of isolation and ERIC2 genotype, with the exception of ERIC D, which showed a significant decline in isolation with time (p=0.019)., Conclusions: ERIC genotypes were stable over this period, except genotype C which was lost during this time. Previous molecular typing methods showed campylobacters to be heterogeneous but this study suggests that the local human Campylobacter population consists of several common and stable genotypes. This study has established a database of local ERIC2 genotypes. This methodology may allow the establishment of an all-island database of clinical campylobacters that would be valuable in reducing human campylobacteriosis in Ireland.

Background: Cryptosporidium parvum is the most common of the protozoal pathogens associated with gastrointestinal disease in Northern Ireland. Genotyping techniques are valuable in helping to elucidate sources and modes of transmission of this parasite. There have been no reports on the prevalence of genotypes in Northern Ireland, mainly due to a lack of discriminatory genotyping techniques, which recently have become available., Aim: To investigate the genotype of C. parvum oocysts isolated from human faeces in sporadic cases of cryptosporidiosis in Northern Ireland., Methods: Thirty-nine isolates of C. parvum, representing 79.6% of the total 1998 laboratory reports for the Eastern Health and Social Services Board, were investigated. Following DNA extraction from oocysts the thrombospondin-related adhesive protein 2 (TRAP-C2) locus was amplified by polymerase chain reaction (PCR) and subsequently sequenced., Results: The majority of isolates (87.2%) were classified as bovine genotype II with the remainder (12.8%) being the human genotype I., Conclusions: There is a high prevalence of the bovine genotype II parasite in sporadic cases around the greater Belfast area. Epidemiologically, this suggests that the most frequent mode of transmission may be from animals to humans, but does not suggest a high proportion of human to human spread.

Background: Campylobacter species are the most common known bacterial cause of acute diarrhoeal disease and incidences are increasing yearly in Ireland. Concern is expressed that this increase may be due to poor laboratory techniques in recognising these organisms as they are fastidious and technically demanding to culture., Aims: To evaluate and compare the efficacy of seven commercially available basal broth media for the laboratory cultivation of thermophilic C. jejuni and C. coli isolated from foods and clinical specimens, as well as for optimal laboratory passage., Methods: Four strains of Campylobacter spp., including two C. jejuni and two C. coli isolated from pigs were used to compare the quantitative growth of cells on seven commercially available basal culture broths. These included nutrient broth (NB), nutrient broth no. 2 (NB2), Mueller-Hinton broth (MH), brucella broth (BB), brain heat infusion broth supplemented with 0.6% (w/v) yeast extract (BHIYE), tryptone soya broth supplemented with 0.6% (w/v) yeast extract (TSBYE) and Campylobacter broth (KAMPY) employing a spectrophotometrical growth assay model., Results: Mean absorbance results of the broth media comparison for each strain and statistical analysis of variance allowed the basal media to be ranked into the order, based on proliferation of organisms: BHIYE > TSBYE > BB > NB2 > MHB > KAMPY > NB CONCLUSION: These studies support laboratory employment of either BHIYE or TSBYE for optimal recovery of C. jejuni and C. coli and avoidance of nutrient broth.