Transepithelial potential difference

Transepithelial potential difference (TEPD) is the voltage across an epithelium, and is the sum of the membrane potentials for the outer and inner cell membranes. Transepithelial potential difference (TEPD) is the voltage across an epithelium, and is the sum of the membrane potentials for the outer and inner cell membranes. The diagnosis of Cystic Fibrosis (CF) is usually based on high sweat chloride concentrations, characteristic clinical findings (including sinopulmonary infections), and/or family history. However, a small portion of patients with Cystic Fibrosis especially those with 'mild' mutations of the Cystic Fibrosis Transmembrane Regulator ion channel (CFTR), have near-normal sweat tests.