Advanced Diagnostic Laboratories

Sweat Test

Test Code

SWEAT

Description

Serum chloride is the major extracellular anion and counter-balances the major cation, sodium, maintaining electrical neutrality of the body fluids. Two thirds of the total anion concentration in extracellular fluids is chloride and it is significantly involved in maintaining proper hydration and osmotic pressure. Movement of chloride ions across the red blood cell membrane is essential for the transport of biocarbonate ions in response to changing concentrations of carbon dioxide. Chloride measurements are used in the diagnosis and treatment of electrolyte and metabolic disorders such as cystic fibrosis and diabetic acidosis.

Collect

Sweat Chloride Sample

Onsite [NJH]: Transport to lab within 1 hour.

Preferred Volume: 30 mcL

Minimum Volume: 15 mcL

Storage Transport Temp

Room Temperature

Stability

72 hours at 2-25°C when stored in 0.2 mL micro centrifuge tube; 30 days frozen at -20°C

Performed

Batch tested once per day Monday and Friday

Methodology

Coulometric titration

Turnaround Time

Sweat Chloride testing performed Monday and Friday; testing complete by 7pm.

Department

Core Lab

Study Offerings

RUO

Reference Interval

Age	Normal Range	Intermediate Range	Indicative of CF Range
Infants (0-6 months)	Cl- ≤ 29 mmol/L	Cl- 30-59 mmol/L	Cl- ≥ 60 mmol/L
Beyond Infancy (6 months-18years)	Cl- ≤ 39 mmol/L	Cl- 40-59 mmol/L	Cl- ≥ 60 mmol/L
Adults (>18 years)*	Cl- ≤ 39 mmol/L	Cl- 40-59 mmol/L	Cl- ≥ 60 mmol/L