PROFILE OF CAUCASIAN WOMEN WITH POSSIBLE GENETIC PREDISPOSITION TO REFLEX SYMPATHETIC DYSTROPHY - A PILOT-STUDY

Objectives: To test possible human lymphocyte antigen (HLA) associatio ns in subjects with reflex sympathetic dystrophy (RSD), and to determi ne correlation of HLA associations to treatment outcomes. Design: Iden tification of class I (HLA-A, B, C) and class II (HLA-DR and DQ) (MHC) antigens by well-defined reagents in patients with RSD. Setting and P atients: The HLA analysis was performed on 15 Caucasian women attendin g a university pain clinic and diagnosed with RSD on the basis of stri ct inclusion and exclusion criteria. Outcome Measures: Resistance to t reatment was defined on the basis of lack of response to conservative management, failure to experience long-term symptom relief after sympa thetic blocks, recurrence of pain after sympathectomy, need for pallia tive treatment, and degree of residual disability at the end of all tr eatments. Results: A twofold increase of A3, B7, and DR2(15) MHC antig ens was observed in the study population compared to control frequenci es. Eighty (five of six) of DR2(15)-positive patients proved to be res istant to treatment. Conclusions: The results of this pilot study are the first to suggest a possible genetic diathesis in RSD patients with poor treatment outcome. If this finding can be confirmed in larger st udies, strictly defined RSD could constitute the third neuroimmune dis order (besides multiple sclerosis and narcolepsy) associated with DR2( 15). Gene(s) conferring susceptibility to RSD may be present within or near the MHC region of the short arm of chromosome 6. Due to the smal l size of our study group it is imperative that larger studies be done in RSD patients employing strict diagnostic criteria to confirm or re fute our original observations.