Immunoassay of pyridinoline crosslink excretion in normal adults and in Paget's disease.
A new immunoassay (ELISA) based on an antiserum that preferentially recognizes the free form of the pyridinoline (Pyr) crosslink was used to assess the urinary excretion of Pyr in a large normal sample of the population comprising 236 men and 193 women 30-90 years of age. Urinary Pyr increased significantly with age in both sexes. In women Pyr was higher than in men (57 +/- 21 versus 46 +/- 17 nmol/mmol creatinine, p < 0.001), and the menopause was reflected by a mean 37% increase, from an average 43 to 59 nmol/mm creatinine (p < 0.001). In 52 patients with active Paget's disease of bone, Pyr excretion was markedly increased (206 +/- 160 nmol/mmol creatinine, p < 0.001 versus controls) and decreased by 71% after 3 days of IV treatment with the bisphosphonate pamidronate. Free Pyr measured by the ELISA and the total urinary excretion measured by HPLC were highly correlated both in normals (n = 74, r = 0.83, p < 0.001) and in Pagetic patients (n = 20, r = 0.93, p < 0.001). The mean intra- and interassay coefficients of variation of the ELISA were below 9 and 15%, respectively. It is concluded that this new convenient immunoassay of Pyr should be valuable for the clinical investigation of patients with osteoporosis and other metabolic bone diseases.
Delmas
P D
PD
INSERM Unit 234, Hôpital Edouard Herriot, Lyon, France.
Gineyts
E
E
Bertholin
A
A
Garnero
P
P
Marchand
F
F
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000652:urine*; D002851:Chromatography, High Pressure Liquid; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008593:Menopause; D008875:Middle Aged; D010001:Osteitis Deformans / Q000652:urine*
D000596:Amino Acids; C015484:pyridinoline