Background In rheumatoid arthritis (RA) circulating immune complexes lead to systemic vasculitis of autoimmune origin (A-SV) which may involve various organs. RA as well as autoimmune diseases may be complicated by septic infections (SI) and accompanied with systemic vasculitis of infectious origin (S-SV). In case of systemic vasculitis the identification of its origin is of crucial importance because of the basic differences in therapy.
Objectives The aim of this study was to compare the prevalence, average incidence and severity of A-SV and S-SV in various organs of RA patients.
Methods At the National Institute of Rheumatology 12138 patients died between 1969 and 2000; among them 234 with RA and all of them were autopsied. Lethal septic infection (SI) was observed in 31 (13.25%) of 234 patients. SI was accompanied in 5 patients with S-SV. The clinically identified pathogenic agents and the strong, significant and positive correlation between S-SV and SI (association coefficient: 1, c2=26.1881, p<0.00007) supported the infectious origin of SV.
The prevalence, average incidence and severity of S-SV in twelve organs of these 5 RA patients was determined histologically and compared with 33 RA patients with A-SV of our previous study .
Results The prevalence in % and the average incidence and severity of A-SV (n=33) and S-SV (n=5) in various organs of 38 RA patients are summarized in the table.
Conclusions The involvement (prevalence in %) of various organs, the average incidence and severity of A-SV and S-SV are basically determined by the systemic circulation and blood supply of various organs, by circulating immune complexes and other agents, furthermore by their possible elimination. The source of infection may have a modifying effect regarding the organ manifestation of S-SV.
A-SV was most dominant in the heart, skeletal muscles, lung, pancreas, and kidneys, the main targets of circulating immune complexes in RA. In septic RA patients the S-SV dominated in the heart, skeletal muscles, kidneys, and gastrointestinal tract, which may be due to the complex effect of circulation and source of septic infection (e.g. high prevalence of urogenital and gastrointestinal infections in our autopsy population).
Bély M, Apáthy Άgnes. Clinical pathology of rheumatoid arthritis: Cause of death, lethal complications and associated diseases in rheumatoid arthritis. 1–440 pp. Akadémiai Kiadό, Budapest 2012 http://www.akkrt.hu/p>
Disclosure of Interest None declared