Survey ofPseudomonas aeruginosagenotypes in colonised cystic fibrosis patients

Abstract

The current authors aimed to examine whether cystic fibrosis (CF) patients in Belgium shared Pseudomonas aeruginosa genotypes and to compare the genotypes of isolates from the same patients during two consecutive years. A Belgian databank of the P. aeruginosa genotypes of all colonised CF patients was created.Sputum samples from a total of 276 P. aeruginosa colonised patients during 2003, and from a subgroup of 95 patients in 2004, were analysed. Patients were asked about any social contact between each other by questionnaire. All P. aeruginosa isolates exhibiting different colonial morphology on McConkey agar were first genotyped using arbitrarily primed PCR, whereafter single representatives of each randomly amplified polymorphic DNA-type were further genotyped by fluorescent amplified fragment length polymorphism analysis.In the 213 patients from whom P. aeruginosa could be cultured (resulting in 910 isolates), a total of 163 genotypes were found. The majority (75%) of patients harboured only one genotype. In most of the limited number of clusters, previous contacts between patients could be suspected. In 80% of the patients studied during both years, P. aeruginosa genotype remained unchanged.In conclusion, most colonised cystic fibrosis patients harbour only one Pseudomonas aeruginosa genotype, despite showing different colonial morphotypes. The number of clusters is limited, and most patients seem to retain the same genotypic strain during both years.

Pseudomonas aeruginosain the home environment of newly infected cystic fibrosis patients

“…A total of 427 environmental samples were obtained and genotyped with a median number of eight samples per patient (mean (range) samples 8.5 (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)). Nurses were asked to collect a minimum of four samples per home, with at least one sample from the kitchen, bathroom, toilet and the patient's nebuliser.…”

“…This approach is designated ERIC2-PCR in the present study. This allowed a reduction in the number of isolates that were subsequently genotyped by the more laborious fluorescent amplified fragment length polymorphism analysis technique [7], since only single representatives of each ERIC2-PCR type were further genotyped by this procedure. Table 1 presents the epidemiological and sampling data of the patients included.…”

“…DNA fingerprints of the P. aeruginosa isolates from the newly infected patients were compared with fingerprints of P. aeruginosa strains recovered from the home environment. Using the Belgian inventory of the DNA fingerprints of most patient P. aeruginosa isolates [7], the DNA fingerprints of the P. aeruginosa isolates from the newly infected patients were compared with the fingerprints of P. aeruginosa isolates from chronically infected CF patients attending the same CF centre as the newly infected patients. 6 U b.i.d.)…”

“…Patient-to-patient transmission has been well documented. It generally results from prolonged social contact, such as that between siblings [5], close friends or people staying at holiday camps [6,7] and CF rehabilitation centres [7,8].…”

SharedPseudomonas aeruginosagenotypes are common in Australian cystic fibrosis centres

“…However, not all studies have identified evidence of highly prevalent genotypes. Reports from Belgium, British Columbia (Canada) and New Zealand have only identified small clusters of genetically similar isolates in epidemiologically unrelated patients [22][23][24].…”