Role of sweat ion ratios in diagnosing cystic fibrosis

Sweat chloride (Cl − ) concentration is the gold standard for diagnosing cystic fibrosis (CF). This is, however, challenging among patients with borderline values. Previous studies have reported that the sweat Cl − /Na + ratio may be useful for diagnosing CF; however, little is known about Cl − /K + and (Cl − + Na + )/K + ratios. This study aimed to retrospectively define the most appropriate outcome of the sweat test. Samples of sweat were...