Bone metabolism is characterized by two opposing activities coupled in time and space in the so-called ‘bone remodelling units’. Through a continuous remodelling cycle old bone is resorbed by osteoclasts while osteoblasts deposit new bone. Bone loss is due to an imbalance between bone resorption and formation. Biochemical markers provide a dynamic view of the remodelling process, which can improve fracture risk prediction. Furthermore, they can be used to monitor the short-term effects of therapy, treatment efficacy and patient compliance. Markers of bone remodelling can be dosed in plasma and/or urine, as indicators of osteoblast function or osteoclast function. The significance of any bone turnover marker (BTM) depends on two fundamental characteristics: specificity and variability. The biological variability may determine some limitations in the interpretation of the data. Even though some uncertainties on how to interpret a given result are not resolved as yet, it is impossible to ignore the utility of BTM. As they are easy to obtain and inexpensive compared with other not always mandatory examinations, it seems justified to use BTM in our clinical practice.
HIV-related bone disease is characterized by a high turnover state, with an exaggerated osteoclastic bone resorption and delayed osteoblastic bone formation. Few data exist on the relevance of BTM in HIV-infected patient management. Following the considerations drawn for the general population we suggest that, at least in osteoporotic HIV-patients, BTM be used both to increase the ability of fracture prediction and to monitor the response to anti-resorptive therapy.
Keywords: Osteoporosis; HIV; Bone turnover markers.
Articolo presente in – HAART and correlated pathologies n. 2 –