Objective: To define the respiratory burst activity of neutrophils, the total anti-oxidative status of plasma, and the parameters of systemic inflammation in patients with ankylosing spondylitis (AS) before and after a combined radon-hyperthermia treatment in the thermal tunnels of Böckstein-Bad Gastein in Austria.
Methods: In 20 patients with AS the effects of a total of 15 hours of radon-hyperthermia-treatment spread over a period of three weeks were studied. The respiratory burst activity of neutrophils was measured fluorometrically using dichlorofluorescein diacetate, the total anti-oxidant status was measured using azinodiethyl-benzthiazoline-sulphonate, and inflammation parameters were determined by routine laboratory assays.
Results: Before treatment, the basal neutrophil respiratory burst in patients (n = 20) was 409 +/- 62 fluorescence arbitrary units (AU; mean +/- SEM) and 359 +/- 37 AU in controls (n = 9; p > 0.5); the stimulated respiratory burst (fMet-Leu-Phe, 10(-6) M) was 1,027 +/- 133 AU in patients and 1,152 +/- 218 AU in controls (p > 0.5). After treatment, the basal neutrophil respiratory burst in patients (n = 19) was 137 +/- 16 and in controls it was 174 +/- 35 AU (n = 8; p > 0.1); the stimulated respiratory burst was 670 +/- 66 and 1,305 +/- 82 AU, in patients and controls respectively (p < 0.001). No effects of treatment on the total anti-oxidant status of the plasma or on the parameters of inflammation were detected.
Conclusion: Combined radon-hyperthermia treatment reduces the respiratory burst activity of the blood circulating neutrophils in patients with AS. If respiratory burst activity from the neutrophils plays a role in the pathophysiology of ankylosing spondylitis, the observed reduction may be related to the beneficial effects of radon-hyperthermia treatment.