Antibiotic therapy and fat digestion and absorption in cystic fibrosis

Antibiotic therapy in the cystic fibrosis (CF) mouse model has been shown to result in reduced bacterial load of the intestine and significant body mass gain. The effect was suggested to be linked to the improvement of intestinal digestion and absorption. Therefore, we aimed to assess the influence of routinely applied antibiotic therapy in CF patients on fat assimilation. Twenty-four CF patients aged 6 to 30 years entered the study. Inclusion criteria comprised confirmed exocrine pancreatic insufficiency and bronchopulmonary exacerbation demanding antibiotic therapy. Exclusion criteria comprised: antibiotic therapy six weeks prior to the test, liver cirrhosis, diabetes mellitus, oxygen dependency, the use of systemic corticosteroids. In all enrolled CF subjects, (13)C-labelled mixed triglyceride breath test ((13)C MTG-BT) was performed to assess lipid digestion and absorption, before and after antibiotic therapy. Sixteen subjects were treated intravenously with ceftazidime and amikacin, eight patients orally with ciprofloxacin. Cumulative percentage dose recovery (CPDR) was considered to reflect digestion and absorption of lipids. The values are expressed as means (medians). The values of CPDR before and after antibiotic therapy did not differ in the whole studied group [4.6(3.3) % vs. 5.7(5.3) %, p = 0.100] as well as in the subgroup receiving them intravenously [4.6(3.2) % vs. 5.7(5.3) %, p = 0.327] or in that with oral drug administration [4.6(3.4) % vs. 5.7(5.4) %, p = 0.167]. In conclusion, antibiotic therapy applied routinely in the course of pulmonary exacerbation in CF patients does not seem to result in an improvement of fat digestion and absorption.