Test Details
Methodology
ADH: radioimmunoassay (RIA); osmolality: freezing point depression
Result Turnaround Time
4 - 10 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Test Includes
ADH; osmolality
Use
This test is used to aid in the diagnosis of urine concentration disorders, especially diabetes insipidus, syndrome of inappropriate ADH (SIADH), psychogenic water intoxication and syndromes of ectopic ADH production.
Limitations
This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.
Custom Additional Information
ADH, produced in the supraoptic and paraventricular locations of the hypothalamus, acts on the collecting tubules of the kidney to cause increase in permeability to water and urea. ADH release is triggered by a number of both osmotic and nonosmotic stimuli. Measurement of ADH is useful in separating central diabetes insipidus, which is marked by polydipsia and polyuria and is caused by inadequate ADH production from nephrogenic diabetes insipidus caused by the inability of renal tubules to respond to ADH. In SIADH, release of ADH is disproportionate to a low serum osmolality. SIADH results due to a number of conditions such as pulmonary disease, head trauma, and cancer.
Specimen Requirements
Specimen
Serum, refrigerated and plasma, frozen
Volume
1 mL serum and 2 mL plasma
Minimum Volume
0.5 mL serum and 1 mL plasma (Note: This volume does not allow for repeat testing.)
Container
Gel-barrier tube and lavender-top (EDTA) tube
Collection Instructions
Draw serum and plasma samples and separate from cells using a refrigerated centrifuge. Transfer separated samples into clearly labeled “plasma” and “serum” plastic transport tubes. Freeze plasma immediately and refrigerate serum. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Stability Requirements
| Temperature | Period |
|---|---|
| Room temperature | ADH: unstable Osmolality: 14 days |
| Refrigerated | ADH: unstable Osmolality: 14 days |
| Frozen | ADH: 4 weeks Osmolality: 14 days |
| Freeze/thaw cycles | ADH: Not applicable Osmolality: Stable x3 |
Reference Range
• ADH: 0.0−4.7 pg/mL
• Osmolality:
− Neonates: May be as low as 266 mOsmol/kg
− 0 to 60 years: 275−295 mOsmol/kg
− >60 years: 280−301 mOsmol/kg
Storage Instructions
Freeze plasma immediately. Refrigerate serum.
Patient Preparation
No isotopes administered 24 hours prior to venipuncture
Causes for Rejection
Recently administered isotopes; plasma specimen not received frozen
References
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 046557 | Antidiuretic Hormone Profile | 3126-0 | 010449 | ADH | pg/mL | 3126-0 |
| 046557 | Antidiuretic Hormone Profile | 3126-0 | 002071 | Osmolality | mOsmol/kg | 2692-2 |
| Order Code | 046557 | |||||
| Order Code Name | Antidiuretic Hormone Profile | |||||
| Order Loinc | 3126-0 | |||||
| Result Code | 010449 | |||||
| Result Code Name | ADH | |||||
| UofM | pg/mL | |||||
| Result LOINC | 3126-0 | |||||
| Order Code | 046557 | |||||
| Order Code Name | Antidiuretic Hormone Profile | |||||
| Order Loinc | 3126-0 | |||||
| Result Code | 002071 | |||||
| Result Code Name | Osmolality | |||||
| UofM | mOsmol/kg | |||||
| Result LOINC | 2692-2 |