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Mary Crowe

Publications and source records attributed to Mary Crowe.

6 recordsLinked to original sources
PubMed2004

Epidemiology of Burkholderia cepacia complex species recovered from cystic fibrosis patients: issues related to patient segregation.

Studies of the prevalence of Burkholderia cepacia complex species amongst cystic fibrosis (CF) patients in different geographical regions, and the association between cross-infection and putative transmissibility markers, will further our understanding of these organisms and help to address infection-control issues. In this study, B. cepacia complex isolates from CF patients in different regions of Europe were analysed. Isolates were examined for B. cepacia complex species and putative transmissibility markers [cable pilin subunit gene (cblA) and the B. cepacia epidemic strain marker (BCESM)]. Sporadic and cross-infective strains were identified by random amplification of polymorphic DNA (RAPD). In total, 79% of patients were infected with Burkholderia cenocepacia (genomovar III), 18% with Burkholderia multivorans (genomovar II) and less than 5% of patients with B. cepacia (genomovar I), Burkholderia stabilis (genomovar IV) or Burkholderia vietnamiensis (genomovar V). The cblA and BCESM transmissibility markers were only detected in strains of B. cenocepacia. The BCESM was a more sensitive marker for transmissible B. cenocepacia strains than cblA, although sporadic B. cenocepacia strains containing the BCESM, but lacking cblA, were also observed. Furthermore, clusters of cross-infection with transmissibility marker-negative strains of B. multivorans were identified. In conclusion, B. cenocepacia was the greatest cause of cross-infection, and the most widely distributed B. cepacia complex species, within these CF populations. However, cross-infection was not exclusive to B. cenocepacia and cblA and the BCESM were not absolute markers for transmissible B. cenocepacia, or other B. cepacia complex strains. It is therefore suggested that CF centres cohort patients based on the presence or absence of B. cepacia complex infection and not on the basis of transmissibility marker-positive B. cenocepacia as previously suggested.

Bacterial Typing Techniques↗
PubMed2003

Identification of a novel alpha-proteobacterium causing bacteraemia in an immunocompetent patient.

An 89-year male with pyrexia and suspected bacteremia was admitted to hospital, where a Gram-negative rod was identified from blood culture. The organism was difficult to identify phenotypically and the resulting sequencing of a 559 bp section of the 16S rRNA gene did not have a high homology score (>97.0%) with any deposited GenBank accession numbers and hence was not able to be assigned to a species within any genus. Given that the isolate was a member of the alpha subclass of the Proteobacteria but did not fall into any of the known genera with more than 93.7% homology (Brucella, Rhizobium, Ochrobactrum, Agrobacterium), we believe this isolate to represent a novel alpha-proteobacterium, which was the cause of bacteraemia in this patient.

Aged↗
PubMed2003

Development of a diagnostic PCR assay that targets a heat-shock protein gene (groES) for detection of Pseudomonas spp. in cystic fibrosis patients.

Laboratory detection of Pseudomonas spp., in particular Pseudomonas aeruginosa, remains an important assay in the management of patients with cystic fibrosis (CF). As the groES and groEL genes of P. aeruginosa have now been cloned and their nucleotide sequences determined, the aim of this study was to develop a novel PCR assay for the detection of Pseudomonas spp. from patients with CF by employing conserved primer regions of the groE heat-shock protein domain gene. A PCR assay was designed that targeted a 536 bp region of the groE gene to detect Pseudomonas spp. PCR amplification of genomic DNA from extracted organisms generated an amplicon of the expected size (approx. 536 bp) for all P. aeruginosa (n = 60), Pseudomonas putida, Pseudomonas fluorescens and Pseudomonas stutzeri isolates examined, but did not produce a positive amplicon for several other genera and species that are commonly isolated from the sputum of CF patients. RFLP analysis of the amplicons of all P. aeruginosa isolates demonstrated a single RFLP type that consisted of three bands at approximately 80, 190 and 250 bp; direct sequencing of the amplicons demonstrated the presence of a single sequence type, indicating the highly conserved nature of this region. In addition, the assay successfully produced a positive signal from primary non-selective plates of three known P. aeruginosa culture-positive CF patients, but was unable to generate a signal in a further six CF patients who had no history of infection with P. aeruginosa or other Pseudomonas spp. This assay is recommended to detect the presence of Pseudomonas spp., including P. aeruginosa, from primary culture plates that originate from laboratory analysis of CF patients' sputum, particularly at review, in those patients with no previous history of Pseudomonas infection or those who appear to be transiently colonized by this organism. Employment of such molecular methodologies, in conjunction with routine clinical sputum cultures, may provide improved information on the microbial status of CF patients, which will aid clinicians in both optimum patient management in terms of antibiotic regimes and CF centre infection-control practices.

Adolescent↗
PubMed2002

Primary (isolated) meningococcal pericarditis.

A 19-year-old man was admitted with a history and examination findings of probable bacterial pericarditis. Blood cultures produced Neisseria meningitidis Group C, sensitive to penicillin. The patient was initially treated with intravenous benzylpenicillin. Echocardiogram demonstrated the development of a pericardial effusion which was tapped, and benzylpenicillin was instilled into the pericardial space. Because of failure of clinical resolution, cefotaxime was substituted for benzylpenicillin. Rapid clinical improvement then ensued. Repeat echocardiogram showed evidence of neither reaccumulation nor constrictive pericarditis. Primary (isolated) meningococcal pericarditis is a recognized though rare manifestation of meningococcal disease. It is most common in young adults and is associated with a good prognosis.

Adult↗
PubMed2002

Improved molecular detection of Burkholderia cepacia genomovar III and Burkholderia multivorans directly from sputum of patients with cystic fibrosis.

Optimum detection of the Burkholderia cepacia complex (BCC) from sputum of patients with cystic fibrosis (CF) is essential in preventing patient-to-patient transmission of this organism. The aim of this study was to develop an improved PCR assay with reference to sensitivity for the direct detection of BCC organisms from CF sputum employing the recA locus. The sensitivity results of three recA PCR assays were compared using various combinations of previously published primers. These included (i) a single-round approach using the primer set BCR1/BCR2, yielding a 1036-bp product, (ii) a single-round approach using the primer set BCR1/Mr, yielding a 465-bp product, and (iii) a semi-nested PCR (SN-PCR) approach using the primer set BCR1/BCR2 followed by BCR1/Mr. The sensitivity of these assays were determined by spiking B. cepacia-free sputum with known numbers of four strains of BCC, namely, genomovar II [B. multivorans] (C1576), genomovar IIIa (C5424, C6433) and genomovar IIIb (C1394). Following optimization, the chosen assay was performed on 14 patients. Employment of the single-round assay with BCR1/BCR2 was the least sensitive with a detection threshold of 10(7) cfu/g sputum for GIIIa and GIIIb, and 10(8) cfu/g sputum for GII. Sensitivity was improved by targeting the smaller amplification region of the recA locus (465 bp) employing the BCR1/Mr primer pair, in combination with a single-round approach, whereby the detection threshold was improved by 1 log for each genomovar. Employment of the semi-nested assay demonstrated optimum sensitivity, whereby the detection threshold increased to 10(1) and 10(2) cfu/g sputum for genomovar IIIa/IIIb and genomovar II, respectively. Subsequent genomovar characterisation can be performed by sequencing of the PCR amplicon without the need for culture which may be beneficial in patients in the initial stages of colonisation or who are transiently colonised and who may be culture-negative for BCC.

Adult↗