The Electrical Conductivity of Electrolytes Found in the Sweat of Patients with Fibrocystic Disease of the Pancreas

Simultaneous chemical and electrical conductivity studies have been done on the blood serum and sweat of five children with proven fibrocystic disease of the pancreas. The electrical conductivity tests were made by means of a modified Wheatstone bridge previously described (Bloxsom, 1959). These electrical conductivities in equivalent mEq./l. of sodium chloride, together with the chemical analyses of the serum and sweat, are compared with the normal (Table 1). Comment The electrolytes in sweat are sodium, chloride, potassium and lactic acid, with sodium chloride being the major constituent (Best and Taylor, 1950). The electrical conductivities of the electrolytes present in sweat vary considerably, and in this study ranged from 15 to 60 mEq./l. solutions of sodium chloride in the normal children. In the patients with fibrocystic disease of the pancreas the electrical conductivities ranged from 80 to 150 mEq./l. solutions of sodium chloride. The electrical conductivities of normal and abnormal sweat parallel closely the electrolyte content. Lundgren, Ramanathan, Sen Gupta and Chakravarti (1955) report that, in 25 samples ofsweat obtained from 12 normal subjects, the chloride con-