Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Chloride is an electrolyte. Most of the chloride in the diet is attached to sodium in the form of sodium chloride. It is the major extracellular anion and it is important in maintaining normal acid-base balance and, along with sodium, in keeping normal levels of water in the body. Chloride generally increases or decreases in direct relationship to sodium, but may change without any change in sodium when there are problems with acid-base balance. Chloride is taken into the body through food. Most of the chloride is absorbed by the GI tract, and the excess excreted in urine. Measurement of urinary chloride may be useful in the differential diagnosis of metabolic alkalosis
Specimen container paediatric:
Plain universal container (white top)
Specimen container adult:
Plain universal container (white top) for random sample, palin 24 hour urine collection bottle for 24 hour urine collection
Minimum volume paediatric:
1 mL urine
Minimum volume adult:
1 mL urine
Sample stability:
7 days at 15-25°C,
7 days at 2-8°C,
1 year at -20°C
Transport requirements:
Ambient
Interpretation:
Urine chloride concentration can be used to distinguish surreptitious diuretic abuse and vomiting from Bartter’s syndrome. In all these cases there is hypokalaemia, metabolic alkalosis, hyperreninaemia and hyperaldosteronism with urinary sodium and potassium are also elevated. However, with chronic diuretic abuse or protracted vomiting, urinary chloride concentraion is usually below 20mmol/L and in Bartter’s syndrome the urinary chloride is always elevated. It must be noted however that with recent diuretic intake the urinary chloride may exceed 20mmol/L.
Reference ranges:
2 months to 2 years: 2 – 10 mmol/24h
>2 years to 16 years: 15 – 40 mmol/24h
>16 years: 110 – 250 mmol/24h