Test Code BAP Bone Alkaline Phosphatase, Serum
Reporting Name
Bone Alkaline Phosphatase, SUseful For
Diagnosis and assessment of severity of metabolic bone disease including Paget disease, osteomalacia, and other states of high bone turnover
Monitoring efficacy of antiresorptive therapies including postmenopausal osteoporosis treatment
The assay is not intended as a screening test for osteoporosis.
Measurements of bone turnover markers are not useful for the diagnosis of osteoporosis; diagnosis of osteoporosis should be made based on bone density.
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumSpecimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 0.6 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
Specimen Minimum Volume
0.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 90 days | ||
Ambient | 7 days |
Reference Values
Males
<2 years: 25-221 mcg/L
2-9 years: 27-148 mcg/L
10-13 years: 35-169 mcg/L
14-17 years: 13-111 mcg/L
Adults: ≤20 mcg/L
Females
<2 years: 28-187 mcg/L
2-9 years: 31-152 mcg/L
10-13 years: 19-177 mcg/L
14-17 years: 7-41 mcg/L
Adults
Premenopausal: ≤14 mcg/L
Postmenopausal: ≤22 mcg/L
Day(s) Performed
Monday through Saturday
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
84080
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
BAP | Bone Alkaline Phosphatase, S | 17838-4 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
BAP | Bone Alkaline Phosphatase, S | 17838-4 |
Interpretation
Bone alkaline phosphatase (BAP) concentration is high in Paget disease and osteomalacia.(3)
Antiresorptive therapies lower BAP from baseline measurements in Paget disease, osteomalacia, and osteoporosis. Several studies have shown that antiresorptive therapies for management of osteoporosis patients should result in at least a 25% decrease in BAP within 3 to 6 months of initiating therapy.(4,5) BAP also decreases following antiresorptive therapy in Paget disease.(6)
When used as a marker for monitoring purposes, it is important to determine the critical difference (or least significant change). The critical difference is defined as the difference between 2 determinations that may be considered to have clinical significance. The critical difference for this method was calculated to be 25% with a 95% confidence level.(1)
Clinical Reference
1. Kress BC: Bone alkaline phosphatase: methods of quantitation and clinical utility. J Clin Ligand Assay. 1998;21(2):139-148
2. Kuo TR, Chen CH: Bone biomarker for the clinical assessment of osteoporosis: recent developments and future perspectives. Biomark Res. 2017 May;5:18. doi: 10.1186/s40364-017-0097-4
3. Sharma U, Pal D, Prasad R: Alkaline phosphatase: an overview. Indian J Clin Biochem. 2014 Jul;29(3):269–278. doi: 10.1007/s12291-013-0408-y
4. Kress BC, Mizrahi IA, Armour KW, et al: Use of bone alkaline phosphatase to monitor alendronate therapy in individual postmenopausal osteoporotic women. Clin Chem. 1999 Jul;45(7):1009-1017
5. Garnero P, Darte C, Delmas PD: A model to monitor the efficacy of alendronate treatment in women with osteoporosis using a biochemical marker of bone turnover. Bone. 1999 Jun;24(6):603-609
6. Raisz L, Smith JA, Trahiotism M, et al: Short-term risedronate treatment in postmenopausal women: Effects on biochemical markers of bone turnover. Osteoporos Int. 2000;11:615-620
Report Available
2 to 3 daysMethod Name
Immunoenzymatic Assay