Bone Alkaline Phosphatase (Sendout)
General Information
- Lab Name
- Bone Alkaline Phosphatase
- Lab Code
- RBAPG
- Epic Name
- Bone Alkaline Phosphatase (Sendout)
- External Test Id
- BAP
- Description
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.
Note: 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 on the basis of bone density.
- References
- Mayo Clinic Laboratories Bone Alkaline Phosphatase Clinical & Interpretive Information
- Synonyms
- BAP, Bone Specific Alkaline Phosphatase, BSAP, Skeletal Alkaline Phosphatase
- Components
-
Code Name RBALKP Bone Alkaline Phosphatase
Interpretation
- Method
Immunoenzymatic Assay
- Reference Range
- See individual components
- Ref. Range Notes
Interpretation:
Bone alkaline phosphatase (BAP) concentration is high in Paget disease and osteomalacia.¹
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.¹ BAP also decreases following antiresorptive therapy in Paget disease.¹
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
- Interferences and Limitations
Cautions:
Assay results should only be used in conjunction with information available from the clinical evaluation of the patient and other diagnostic procedures.
Human antimouse or other heterophile antibodies may be present in patient specimens. Although the assay has been specifically formulated to minimize their effects on the assay, results from patients known to have these antibodies should be carefully evaluated.
Liver-derived alkaline phosphatase (ALP) has some cross-reactivity in this assay: 100 U/L of liver ALP activity gives a result of 2.5 mcg/L to 5.8 mcg/L. Accordingly, serum specimens with significant elevations of liver ALP activity may yield elevated results.
- References
- Mayo Clinic Laboratories Bone Alkaline Phosphatase Clinical & Interpretive Information
Ordering & Collection
- Specimen Type
- Blood
- Collection
-
3 mL blood in GOLD SST or RED TOP tube
- Handling Instructions
Outside Laboratories: Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.
Stability: Refrigerated (preferred): 14 days; Frozen: 90 days; Ambient: 7 days.
Reject Due To: Gross hemolysis. Gross lipemia is acceptable.
- Quantity
-
Requested: 0.6 mL serum
Minimum: 0.5 mL serum
Processing
- Receiving Instructions
Centrifuge sample and transfer serum to a separate plastic vial. Refrigerate serum.
Sendouts:
- Order Mayo Test: BAP.
- Interfaced: Yes.
Stability: Refrigerated (preferred): 14 days; Frozen: 90 days; Ambient: 7 days.
Reject Due To: Gross hemolysis. Gross lipemia is acceptable.
- Misc Sendout
Performance
- Lab Department
- Sendouts Mayo Lab (RF)(MARF)
- Frequency
- Performed: Monday - Saturday. Report Available: 2-3 days.
- Available STAT?
- No
- Performing Location(s)
-
Sendout Mayo Clinic Laboratories (Superior Drive)
800-533-17103050 Superior Drive NW
Rochester, MN 55901
Billing & Coding
- CPT Codes
- 84080
- LOINC
- 17838-4
- Interfaced Order Code
- UOW5139