Shwachman-Kulczycki score and resting energy expenditure in cystic fibrosis.

BACKGROUND: Disease severity assessed by clinical scores in cystic fibrosis (CF) has been a topic of investigation for many years, although a correlation of clinical scores with resting energy expenditure (REE) has not been described yet. We aimed to assess disease severity as evaluated by the Shwachman-Kulczycki (SK) score and to correlate these findings with REE and forced expiratory volume in 1 s (FEV1). METHODS: Twenty-eight patients performed respiratory function testing (FEV1), and assessment of REE with open circuit indirect calorimetry. The SK score was evaluated according to general activity, physical examination, nutrition and conventional chest X-ray findings. RESULTS: Mean SK score was 75.3 +/- 15.7. Mean REE was 109.1% of predicted vs. 96.5% predicted in 16 healthy subjects (P = 0.002). There was a significant correlation between the SK score and REE (P = 0.001), the SK score and FEV1 (P < 0.001) and REE and FEV1 (P = 0.034). CONCLUSIONS: The correlations between the SK score, REE and FEV1 demonstrate a close connection between disease severity, caloric requirement and lung damage. They confirm the clinical value of the SK score, which is easy to assess in a clinical setting.