Test Code LAB1070 Bone Alkaline Phosphatase, Serum
Additional Codes
BAP
Useful 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
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)
Method Description
The instrument used is a Beckman Coulter Unicel DXI 800. The Access Ostase assay is a one-step immunoenzymatic assay used to measure bone alkaline phosphatase (BAP) in human serum. The assay utilizes a mouse monoclonal antibody specific to BAP and paramagnetic particles coated with goat antimouse antibodies. BAP in the patient's specimen binds to the anti-BAP mouse antibody, which in turn is captured by the solid phase antimouse antibody. After washing to remove any unbound material, a chemiluminescent substrate is added to the reaction vessel. The BAP present acts on the substrate to produce light, which is measured with a luminometer. The amount of light produced is directly proportional to the amount of BAP in the specimen. The amount of analyte in the specimen is determined from a stored, multipoint calibration curve.(Package insert: Access Ostase. Beckman-Coulter; 2019)
Report Available
2 to 3 daysSpecimen Retention Time
14 daysReject Due To
Gross hemolysis | Reject |
Gross lipemia | OK |
Method Name
Immunoenzymatic Assay