Bone alkaline phosphatase measured with a new immunoradiometric assay in patients with metabolic bone diseases.
We have investigated the clinical utility of a new quantitative two-site radioimmunometric assay specific for bone alkaline phosphatase (B-ALP) in 219 healthy control subjects and in 264 patients with various metabolic bone diseases. B-ALP was compared with total alkaline phosphatase (T-ALP) and with osteocalcin (BGP). B-ALP increased linearly with age in both sexes. In postmenopausal normal women B-ALP increased by 82% compared with premenopausal normal women, whereas the differences between pre- and postmenopausal women for T-ALP and BGP were 18% and 30% respectively. As assessed by Z-score, the highest values of B-ALP were found in patients with Paget's disease of bone, bone metastases or hyperparathyroidism and in patients on maintenance haemodialysis. In osteoporotic patients, B-ALP< but not T-ALP, showed a slight but significant (P < 0.05) difference compared with normal women. On the basis of bone turnover, osteoporotic patients were divided into two groups: high turnover and low turnover; B-ALP, like BGP, was significantly (P < 0.01) higher in patients with high turnover. In conclusion, B-ALP, measured by this new method, can be considered a sensitive marker of bone turnover and could be especially useful in identifying women at risk of developing osteoporosis.
Gonnelli
S
S
Institute of Internal Medicine and Medical Pathology, University of Siena, Italy.
Cepollaro
C
C
Montagnani
A
A
Monaci
G
G
Campagna
M S
MS
Franci
M B
MB
Gennari
C
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over / Q000502:physiology; D000375:Aging / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism*; D015415:Biomarkers / Q000032:analysis; D001847:Bone Diseases / Q000175:diagnosis* / Q000201:enzymology; D016723:Bone Remodeling / Q000502:physiology; D001842:Bone and Bones / Q000201:enzymology*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000032:analysis / Q000097:blood; D015663:Osteoporosis, Postmenopausal / Q000175:diagnosis / Q000201:enzymology; D017698:Postmenopause / Q000502:physiology; D011863:Radioimmunoassay / Q000379:methods*
D015415:Biomarkers; D015675:Osteocalcin; D000469:Alkaline Phosphatase