Chronical carrier for Pseudomonas aeruginosa

Question

Hello,
My 11-year-old daughter is affected by CF. After a culture of a sputum control, 2 different strains of Pseudomonas aeruginosa (P.a.) were found (P.a. has been found in an irregular way since she is 18 months old).
The doctor informed me that he didn't want her to have an intravenous antibiotic cure IV and that he would give her a per os medication only if she has clinical signs (fever, cough) and to pursue the inhalation with colistin twice a day. She evokes problems of resistance to antibiotics knowingly that her last intravenous antibiotic cure goes back up to 2 years and that her last ciprofloxacine treatment goes back up to 1 year.
I do not question the competence of her doctor but I'm afraid of the risk of irreversible lung damages?
Thank you for the explanations that you can bring me because I am very worried and we want to go on holiday in 10 days to Italy: moment for which she waits for a long time.

Answer

Hello,
The situation which you describe makes me think about the situation that your daughter presents an "occasional" or "intermittent" colonization with Pseudomonas aeruginosa. An intermittend colonization is defined by less than 50% positive airway cultures for Pseudomonas aeruginosa in the last year (at least 6 samples should have been taken over the year). A chronic colonization is defined by at least 50% or more P.a. positive airway cultures within the last year. Both situations acute/intermittent and chronic have to be distinguished.
If we have a new finding of P.a., an early antibiotic eradication therapy is recommended in the latest guidelines. There is no consensus about the best strategy, however, most data suggest, that either 28 days of inhalation of Tobramycin or a combination therapy with Ciprofloxacin orally and inhalative Colistin are suitable. Therefore, an i.v. antibiotic therapy is not necessary, but can be considered in special cases, e.g. if the patient is not well.
In case we have a chronic colonization with P.a., permanent inhalation with an antibiotic is recommended (Tobramycin, Colistin or Aztreonam for example in different ways, like 4 weeks on/off or continuously). I.V. antibiotic courses are done in some countries/centers regularly, in others only if the patients show symptoms of pulmonary exacerbations.
From this you can see, that the finding of P.a. requires antibiotic treatment, however, there are some options in which way those antibiotics can be given; in most cases the inhalative way is the way of choice and an i.v. treatment becomes necessary only if the inhalative eradication fails or if the patient shows clinical symptoms.
To which group of Pseudomonas aeruginosa colonized patients your daughter belongs and which treatment is the right one for her, can only be decided by the physician in charge, who knows all results and the patient well.

Best regards
Pr Philippe Reix and Dr. Daniela d'Alquen

09.07.2014