Ankylosing spondylitis, psoriatic arthritis, and reactive arthritis show increased bone resorption, but differ with regard to bone formation.
OBJECTIVE
To test if markers of bone metabolism are altered in patients with seronegative spondyloarthropathies (SSpA).


METHODS
We studied biochemical markers of bone resorption and bone formation, osteoprotegerin (OPG), and bone mineral density (BMD) in patients with psoriatic arthritis (PsA), ankylosing spondylitis (AS), and reactive arthritis (ReA) and healthy volunteers.


RESULTS
The bone resorption markers urinary deoxypyridinoline and crosslinked telopeptide of collagen-I were significantly increased in patients with AS, PsA, and ReA; in PsA they correlated with the acute phase response (C-reactive protein and erythrocyte sedimentation rate). The bone formation markers were divergent: bone-specific alkaline phosphatase was increased in PsA, but not in AS or ReA. Osteocalcin levels were only elevated in AS. Serum levels of OPG were significantly increased in both AS and PsA. Dual energy x-ray absorptiometry (DEXA) measurements of lumbar spine and femoral neck revealed osteopenia in patients with AS, whereas the DEXA distribution was within normal range in PsA.


CONCLUSIONS
Our data indicate high and, particularly in AS, unbalanced bone turnover in SSpA, consistent with the decrease in BMD found in patients with AS.
Department of Internal Medicine III, University of Vienna, Austria. Johannes.Grisar@akh-wien.ac.at
Johannes
J
Grisar
Peter M
PM
Bernecker
Martin
M
Aringer
Kurt
K
Redlich
Markus
M
Sedlak
Wolfgang
W
Wolozcszuk
Susanne
S
Spitzauer
Stephan
S
Grampp
Franz
F
Kainberger
Wolfgang
W
Ebner
Josef S
JS
Smolen
Peter
P
Pietschmann
D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D000368:Aged; D000596:Amino Acids / Q000032:analysis; D015535:Arthritis, Psoriatic / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D016918:Arthritis, Reactive / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D015415:Biomarkers / Q000032:analysis; D015519:Bone Density / Q000502:physiology; D001862:Bone Resorption / Q000175:diagnosis* / Q000209:etiology; D015331:Cohort Studies; D005260:Female; D006023:Glycoproteins / Q000032:analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000032:analysis; D053244:Osteoprotegerin; D011336:Probability; D011379:Prognosis; D000091402:Prohibitins; D011446:Prospective Studies; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis; D018124:Receptors, Tumor Necrosis Factor; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013167:Spondylitis, Ankylosing / Q000097:blood / Q000150:complications / Q000175:diagnosis*; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D000596:Amino Acids; D015415:Biomarkers; D006023:Glycoproteins; D053244:Osteoprotegerin; C000717331:PHB2 protein, human; D000091402:Prohibitins; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C506030:TNFRSF11B protein, human; D014409:Tumor Necrosis Factor-alpha; D015675:Osteocalcin; C036020:deoxypyridinoline