Long-term antibiotics therapy, what dosage? With which antibiotics? Alternating antibiotics?

Question

Hello,

at the recommendation of the CF clinic, we have now decided to start long-term antibiotics therapy with our daughter (15 months) at least over the winter. What antibiotics should we choose? Does one have to switch antibiotics in between due to the risk of resistances? What dosage does one choose by default? Due to staphylococcus aureus in the pap smear, we started with cephazolin and switched to cephadroxil after 4 weeks, and the staph is no longer detectable. She weighs about 11kg and is getting 250mg twice a day [translator’s comment: not sure that this is the correct translation/whether is indeed twice a day]. Do you consider this sensible?

Thank you for your effort.

Answer

Hello,

strategies to avoid lung damage caused by problem germs in small children with CF differ greatly and are sometimes discussed controversially.

Essentially, though, it has to be said that the consistent use of antibiotics is a major reason for the significant improvement of the course of disease in CF during the past decades. The benefit of antibiotics for children with CF is usually greater than the risk of potential side effects. We therefore like to summarize our approach as follows: the goal is not to avoid antibiotics but to avoid damages to and scars on the lungs. If your child does not have Pseudomonas, an antibiotics therapy of 2-4 weeks is widely recommended, e.g. with drugs that are effective against staphylococcus, in case of a respiratory infection, increased cough, and/or mucus. We appreciate it if a deep throat pap smear is done or sputum taken; at least when the antibiotics are not successful.

If your child does have a chronic Pseudomonas, most CF centers in Germany recommend inhaling antibiotics twice a day with tobramycin or colistin as a long-term therapy along with regular i.v. antibiotics cycles or oral treatments with ciprofloxacin – with concurrent colistin inhalations.

Your 15-month-old daughter does not seem to have a chronic Pseudomonas aeruginosa, though. I therefore assume that your question is aiming at a long-term antibiotics treatment against staphylococcus. Some toddlers with CF contract respiratory infections so frequently during the winter months that a long-term antibiotics treatment can make sense. Some centers used to do this with CF children and adults right from the start, irrespective of either their clinical condition or a colonization with germs. Statistically, patients who were treated this way showed fewer symptoms of the respiratory tracts, and the frequency of hospital admissions was lower. Differences in lung function could not be proven, however. In addition, studies by Ratjen et al. (Pediatric Pulmonology 2001; 31:13-16), for instance, showed that patients with such a long-term prophylaxis have a higher risk of Pseudomonas colonization of the lungs statistically.

In conclusion, a low threshold for using antibiotics makes sense. With CF, they should be administered over extended intervals of 2-4 weeks. In general, a long-term antibiotics prophylaxis cannot be recommended; in individual cases – e.g. over a limited time, with repeated evidence of problem germs and/or elevated inflammation values – this could be considered, however. If antibiotics are given over a longer period of time, switching between different ones occasionally can make sense in order to avoid resistances. In Germany, popular antibiotics include cefradoxil, cefaclor, cefuroxime, amoxicillin with clavulanic acid, or cotrimoxazole (as a second choice). Recommendations about dosage can be taken from the current CF manual by Ballmann and Smaczny (UNI-Med 2008).

Dr. Jochen Mainz

23.11.2009