Stenotrophomonas maltophilia

Question

Hello,
We learned one month after birth that our 4 months-old daughter was diagnosed with CF. She carries the DF508 and G3272-26A mutations.
She is followed up every month at the CF Center X, has respiratory physiotherapy every day and is currently pancreatic sufficient.
My question is, we just learned that she has already Staphylococcus aureus. She was then put under Augmentin for 15 days + physiotherapy twice a day. In the last sputum culture, they have become "rare "but there are traces of Stenotrophomonas maltothilia quantity" rare "also. What’s this bacterium? We were told that it was a bit like Pseudomonas, however, we are taking all precautions regarding stagnant water etc ... The pulmonologist has been very evasive about this bacteria ... How does it work. She will have it for life? Is it serious? I saw that it was resistant to antibiotics ... She has no particular symptoms for the moment ...
We are a bit helpless ...
Thank you

Answer

I already answered your previous question about the future of the Staphylococcus aureus (SA) found in the sputum of your child:

ecorn-cf.eu/index.php?id=65&L=8&tx_expertadvice_pi1[showitem]=3188&tx_expertadvice_pi1[search]=staphy


Since then, your daughter has been treated with an oral antibiotic and an intensification of chest physiotherapy. Your child shows no symptoms anymore and sputum examination finds only rare colonies of germs. The treatment therefore appears to have been effective, the persistence of a few colonies of staphylococcus is not significant, especially if your child is well.
This is also the presence of a few colonies of a new germ that worries you. The Stenotrophomonas maltophilia is a common environmental organism but is found more frequently in people with cystic fibrosis (PWCF). If this germ has the peculiarity of having resistance to certain antibiotics, it does not pose the same problems as Pseudomonas that has to be treated without delay in case of first colonization or re-colonization, even in the absence of clinical symptoms. The goal is to achieve eradication of the germ and prevent the transition to chronic respiratory colonization and infection with this germ.
The guidelines are not as straight for Stenotrophomonas maltophilia. In the current state of knowledge, the strength of proof of "dangerousness" has nothing to do with that of Pseudomonas aeruginosa. A recent issue in Cochrane review made a good summary of the data (see reference in the "Public Comment" tab). In case of positive respiratory sample for this germ, the recommendation is that the decision be made on a case by case basis.
In the situation you describe, namely the discovery for the first time of rare colonies of S. maltophilia in a girl who goes well after antibiotic therapy against SA respiratory infection, it seems reasonable to delay and monitor subsequent samples to see if the bacteria is found and advise based on the clinical course. In young children, it is indeed common that colonization (if one can speak of colonization with only "rare" colonies) is transient and without consequence.
I suggest you talk with confidence to your CF doctor who is best placed to judge the clinical situation of your child.
Sincerely.
Gilles RAULT, MD, Roscoff CF Center
and
Geneviève HERY-ARNAUD, Microbiologist, Brest UH

Antibiotic treatment for Stenotrophomonas maltophilia in people with cystic fibrosis. Amin R, Waters V. Cochrane library ;2014 ;4.

03.12.2014