Resting energy expenditure before and after treatment for Pseudomonas aeruginosa infection in patients with cystic fibrosis.

To investigate whether metabolic rates change after antipseudomonal treatment, resting energy expenditure (REE) was measured in 29 patients with cystic fibrosis (CF) aged 5-27 y before and after a 2-wk course of intravenous antibiotics for the treatment of chronic Pseudomonas aeruginosa infection. Before therapy, mean (+/- SD) REE was increased to 119.0 +/- 11.4% of the predicted normal value (REE%). Seventeen of the 29 patients were classified as having increased baseline REE% (> 115% of predicted, group I), whereas 12 patients had resting energy expenditures within the normal range (group N). After antipseudomonal therapy, mean REE% decreased significantly by 6.2% of predicted. This decline was negatively correlated with the baseline REE% (r = 0.70, P < 0.001). It was most pronounced (-11.3%) in group I whereas patients of group N showed no major changes. These results suggest that antipseudomonal therapy can reduce increased energy requirements of moderately ill CF patients with chronic Pseudomonas aeruginosa infection.