Effect of combined Low-Dose Radon- and Hyperthermia Treatment (LDRnHT) of patients with ankylosing spondylitis on serum levels of cytokines and bone metabolism markers: a pilot study

Abstract
Ankylosing Spondylitis (AS) is a rheumatic disease and almost 50% of the affected patients suffer from osteoporosis. The ratio of Receptor Activator of Nuclear Factor κB Ligand (RANKL) and Osteoprotegerin (OPG) has become an important marker to assess the status of systemic bone metabolism and has been shown to be dysregulated in AS patients. Combined Low-Dose Radon- and Hyperthermia Therapy (LDRnHT) causes pain reduction in patients with AS and induces the cytokine transforming growth factor-β1 (TGF-β1). TGF-β1 acts as an anti-inflammatory cytokine and influences the OPG/RANK/RANKL system. We therefore performed a study on 33 AS patients to investigate the effect of LDRnHT on serum levels of bone metabolism markers and cytokines involved in chronic inflammatory disorders. It is shown that TGF-β1, TNF-α, IL-6, OPG and RANKL levels significantly increased after LDRnHT and that the ratio of OPG over RANKL is significantly elevated.