Achromobacter

Question

Hello,
The last sputum examination for my son showed a low colonization of Achromobacter.
He had an intravenous treatment but that did not work.
I would like to know if you have information on the consequences of this germ to the lungs but also whether it will worsen faster his health.
Thank you in advance for your response.

Answer

Hello,
You ask a question that calls for no simple answer. I consulted our microbiologist who sent me the following information:
Achromobacter xylosoxidans is a Gram-negative bacillus. It is considered an opportunistic pathogen which means it can take advantage of a body weakness (immune deficiency, or pre-existing disease such cystic fibrosis) to grow and cause infection. The natural reservoir is still unknown. It appears that the bacterium is ubiquitous ie widespread in the environment and associated with wetlands. The mode of contamination of patients is unknown.
This is an emerging respiratory pathogen in cystic fibrosis (CF) patients: the frequency of isolation in sputum is increasing in the last ten years. The French CF Registry reported that in 2012, 5.4% of patients followed by CF Centers had at least one positive culture of A. xylosoxidans in that year, against 2.7% in 2001.
Bronchial colonization by A. xylosoxidans occur at any age, contrary to what is observed with Pseudomonas aeruginosa (the “pyocyanic”) whose frequency increases with the age of patients. This colonization can be sporadic, intermittent or chronic.
Although its pathogenicity (ability to cause infections) in CF has been little studied, recent data show that A. xylosoxidans can cause lung inflammation to a level equivalent to that observed with P. aeruginosa, and therefore may be responsible for impaired respiratory function. Some authors report that the presence of the bacterium is often associated with respiratory exacerbations. But the exact clinical consequences of this colonization is difficult to assess because there is little data on the subject. Moreover, in most cases the patients are co-colonized with one or more other pathogens. The involvement of each of these pathogens in the deterioration of respiratory function becomes difficult to assess.
A. xylosoxidans is a bacterial species naturally resistant to many antibiotics. The presence of A. xylosoxidans is generally considered to fit antibiotics in CF although there is no consensus at present on treatment.
About your child, it is important that you discuss with the CF Center doctor: what (s) germ (s) was targeted during the last intravenous antibiotic treatment: the Achromobacter or on another organism? How is its clinical condition, its respiratory function, its chest radiography?
On this information that only your CF team can have, it depends what to do: remake a cure with other antibiotics? First perform a bronchial secretion endoscopic sampling to search for other germs difficult to demonstrate and test their sensitivity to antibiotics?
Hope that this response will be helpful.
Sincerely.
Gilles RAULT, MD, Roscoff CF Center
And Geneviève HERY-ARNAUD, Microbiologist, CHU Brest

13.03.2015