Reflex sympathetic dystrophy: Is the immune system involved?

Objective: Evaluation of immune system function in patients with reflex sym pathetic dystrophy (RSD). Design: Survey on blood samples obtained from RSD patients and from a rando mly selected control group. The lymphocyte populations (T, B, NK cells), an d the activated T cells (CD25, and HLA-Dr-positive CD4 and CD8 cells) were analyzed by flow cytometry with dual-color direct immunofluorescence after whole-blood lysis. Clinical chemistry parameters were analyzed in additiona l serum samples. Setting: Tertiary care center (outpatient rehabilitation clinic). Subjects: Thirteen patients (nine women) with RSD and a control group of 21 healthy individuals. Main Outcome Measures: The results of the flow cytometry analysis of RSD pa tients were related to those of the control subjects. Means were analyzed, and confidence intervals for differences of the means were calculated. The means of the clinical chemical analysis were related to local reference val ues. Results: The flow cytometry analysis did not differ between RSD patients an d healthy controls. Although in some patients an individual parameter of cl inical chemical analysis differed from its reference value, all of the mean values were within reference limits. Stratification on medications with im munomodulatory effects and on probability of a definite diagnosis of RSD ha d no influence on the results. Conclusion: No association between immunologic indices and RSD was found. T his finding is relevant, because recent theories stress that it is not the sympathetic nervous sytem but a local inflammatory reaction that is fundame ntal in the pathogenesis of RSD. The results of this study do not support t his theory. (C) 1998 by the American Congress of Rehabilitation Medicine an d the American Academy of Physical Medicine and Rehabilitation.