[The mechanism of bone loss in rheumatoid arthritis. Description based on a case report].
Various factors influencing bone turnover and bone loss in rheumatoid arthritis (RA) are illustrated using the example of a postmenopausal woman with a highly active RA. In particular, the relationships between disease activity, vitamin D metabolism, parathyroid hormone (PTH) levels and calcium metabolism are described. High disease activity is associated with low levels of 25-hydroxycholecalciferol, and especially of 1.25-dihydroxycholecalciferol. Despite vitamin D deficiency, PTH levels were decreased and histomorphometric investigation of the iliac crest biopsy showed severe osteoporosis but no signs of osteomalacia. Suppression of the inflammatory disease activity of RA led to a normalisation of the serum levels of 1.25-dihydroxycholecalciferol and PTH. This was associated with a reduction in the initially increased levels of bone specific alkaline phosphatase to normal values. This case report shows a close relationship between disease activity and bone turnover in RA and indicates that early investigation and therapy of disturbances of bone metabolism in RA are necessary.
Oelzner
P
P
Selbständiger Funktionsbereich Rheumatologie & Osteologie, Klinik für Innere Medizin III, Universitätsklinikum Jena, Erlanger Allee 101, 07740 Jena. peter.oelzner@med.uni-jena.de
Buttgereit
F
F
Demary
W
W
Franck
H
H
Kern
P
P
Hein
G
G
D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis*; D002118:Calcium / Q000097:blood*; D005260:Female; D006801:Humans; D008875:Middle Aged; D010024:Osteoporosis / Q000097:blood / Q000175:diagnosis*; D010281:Parathyroid Hormone / Q000097:blood*; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood / Q000175:diagnosis*
D010281:Parathyroid Hormone; D014807:Vitamin D; D002118:Calcium