Protect collection and quantify chloride

Pilocarpine iontophoresis stimulates sweat, followed by quantitative collection from an approved forearm or leg site. Avoid inflamed, damaged, infected, or lotion-treated skin, and control current so it does not cross the trunk or heart. Operational guidance is about five minutes of stimulation and no more than 30 minutes of collection. Exact device steps, analyzer, reagent lot, software, and interferences remain a local current-IFU matter.

For a coiled-tubing collector, approximately 15 microliters is the minimum acceptable specimen; gauze or filter paper uses approximately 75 mg. A below-minimum collection is quantity not sufficient, or QNS. It must not be analyzed or pooled with another collection to manufacture adequacy. Duplicate collections may be simultaneous bilateral or separately repeated according to the validated collection protocol; each site is judged separately and never pooled.

Quantitative chloride may be measured by coulometric titration under a validated method. The laboratory verifies accuracy, precision, reportable range, and applicable reference intervals, uses at least two QC levels across the clinically relevant range, and performs calibration verification under its CLIA program. Release a chloride result only after specimen adequacy, required QC, calibration status, and local method criteria are all acceptable.