Reexamining the Minimum Sweat Rate Requirement for Sweat Chloride Testing.

Negligible correlation of sweat rate and [Cl-] suggests the minimum sweat rate for macroduct collectors may be overly stringent. Reporting of [Cl-] in specimens with ≥10 µL (rate ≥0.3 µL/min) may reduce QNS rates without compromising diagnostic accuracy. Preliminary data suggests pooling of bilateral collections may be a feasible option to achieve the required volume for testing.