Systemic Vasculitis in Various Organs of 33 Rheumatoid Arthritis and 11 Progressive Systemic Sclerosis Patients – A Comparative Postmortem Study

Miklos Bely

doi:10.15226/2374-6882/2/2/00120

Abstract

Objective: The aim of this study was (1) to compare the prevalence and severity of Systemic Vasculitis (SV) in various organs of Rheumatoid Arthritis (RA) and of progressive Systemic Sclerosis (SSc) patients, (2) To determine the complications and lethal outcome caused by vasculitis in RA and SSc. Patients and Methods: Twelve organs (heart, lung, liver, spleen, kidneys, pancreas, gastrointestinal tract, adrenal glands, skeletal muscle, peripheral nerve, skin and brain) of 33 RA and of 11 SSc with SV were studied microscopically. RA and SSc were confirmed clinically according to the criteria of the American College of Rheumatology. The basic disease, the complications, and the lethal outcome caused by vasculitis were determined and analyzed retrospectively, reviewing the clinical and pathological reports, tissue samples, and the histological slides. The existence (prevalence) of vasculitis in various organs was determined based on the presence of vasculitis in blood vessels of different calibers. The severity of vasculitis in various organs was evaluated by semi-quantitative, visual estimation on a 0 to 3 plus scale (based on the number of involved vessels/light microscopic field x40). Results and Conclusions: SV was observed in all of 33 RA and 11 SSc patients with variable prevalence and severity. The average value of prevalence and severity/organ in SSc was appreciably higher than that of RA. In RA patients, not all investigated organs were involved with SV and the existence of blood vessels with vasculitis in each organ was different. In SSc patients SV was present in each of the investigated organs, but with different severity. In RA the heart, skeletal muscle, pancreas, lung, kidneys and gastrointestinal tract were most markedly involved, while in SSc the kidneys, spleen, lung, pancreas, heart and gastrointestinal tract were. The high prevalence of SV and the consecutive fibrosis in these organs identify the main targets of autoimmune processes in RA and SSc prior to the more visible skin involvement. The most markedly involved organs denote a favorable site for histological diagnosis of SV, for example skeletal muscle with peripheral nerve (sural nerve) or gastrointestinal tract in RA and the gastrointestinal tract in SSc. The course of the disease, more precisely mortality due to SV,

Highlights

In autoimmune diseases the vascular system is the most important target of immunological processes, manifesting as vasculitis or characteristic structural changes of blood vessels.Systemic vasculitis of autoimmune origin (SV) may be regarded as one of the basic manifestations of rheumatoid arthritis (RA) as well [1]
The existence and severity of vasculitis in 12 organs of 33 RA patients with Systemic Vasculitis (SV) of autoimmune origin is summarized in table 1 and illustrated in figure 1a and Figure 1b
SV led to death in 19 (57.57%) of 33 RA patients: in one case due to coronary arteritis with a large antero septal Myocardial Infarct (MI); in 11 cases SV caused multifocal micro infarcts of the myocardium; in 3 cases vasculitis of the pulmonary and bronchial arterioles and small arteries led to vasculogenic rheumatoid pneumonia with disseminated lobular-sublobular pneumonia (RhPn)

Summary

Introduction

In autoimmune diseases the vascular system is the most important target of immunological processes, manifesting as vasculitis or characteristic structural changes of blood vessels. Systemic vasculitis of autoimmune origin (SV) may be regarded as one of the basic manifestations of rheumatoid arthritis (RA) as well [1]. The vasculitis and vascular changes are so dominant in progressive systemic sclerosis (SSc) that the disease could be regarded as primary vascular disease. According to Gardner “Evidence of circulatory impairment in systemic sclerosis is so frequent that is natural to ask whether this is fundamentally not a vascular disorder“[3]. This view is supported by others [4,5]

Methods

Results

Conclusion