pseudomonas aeruginosa

Question

I heard a German study said that pseudomonas aeruginosa colonization in people with cystic fibrosis depended mainly on their genotype and hygiene measures about stagnant waters were "useless". What do you think?

Answer

A study was published in 2008: "Pseudomonas aeruginosa in the home environment of newly infected cystic fibrosis patients." (ERJ Schelstraete 2008, 31:822 - www.ncbi.nlm.nih.gov/pubmed/?term=Schelstraete+ERJ+2008% 3B31% 3A822 - if you can read English, this Article is available).

This study demonstrates that it is not easy to determine the origin of pseudomonas aeruginosa colonization at home. For half of the newly colonized patients, P. aeruginosa has not been found in patients' homes, but for the other half, the home environment appears to be involved, including the bathroom as an area at risk.

So as it is now proven that pseudomonas aeruginosa colonization is possible in health care facilities and between patients, the origin of colonization at home remains unclear.

Now it seems too early to say that hygiene measures about stagnant water are useless but we look forward to large-scale studies to guide patients and families to new advice.

Thank you for your question
sincerely
Yann Kerneur

29.04.2013

29.04.13
Indeed, an American Study on this topic has recently been published: the EPIC observational study (Rosenfeld et al., J Cyst Fibros 11:446-453, 2012). 889 CF-children under the age of 12 were included in this study and i.a. data was collected on the genotype and on certain leisure behaviors via questionnaire. It was statistically calculated if those factors could be a risk factor for an early acquisition of P.a.
It came out that the genotype had the greatest influence on the age of first acquisition of P.a.: patients with only minimal residual CFTR-function (two mutations of class I-III) had a median age of 2.9 years at first acquisition of P.a. whilst patients with remaining residual function of CFTR (at least one mutation of class IV-V) had a median age of 10.3 years. None of the evaluated factors, like e.g. usage of a swimming-pool, of a Jacuzzi or participation at social events with other CF-patients came out to be statistically a risk factor for the early acquisition of P.a..
However, experts judge these data differently: some experts are on the basis of the EPIC-study of the opinion that one should not restrict the leisure behavior too much as this study had shown that especially the underlying genotype of the patient is influencing the age at first acquisition of P.a., not however certain behaviors. Other experts contradict, that it had already been known for a long time that the genotype is the most important factor influencing age of first acquisition of P.a. However it would be clear that patients with a “high-risk genotype” would get infected with P.a. if they are exposed to P.a. in great amounts, which remain to be proved by further studies. As a consequence one could indeed delay the age of first acquisition of P.a. via a careful behavior with P.a. exposition as low as possible. Furthermore, the data of this study is methodically not so obvious that one could give concrete advice. Therefore, the data remains fragmentary and recommendations try generally to find a compromise between the actual risk / risk-taking and the loss of quality of life.
D. d'Alquen