الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
BACK GROUND:
Rheumatoid arthritis is a chronic systemic inflammatory disease that affects principally the joints and sometimes many other organs and tissues throughout the body as well. Its pathogenesis involves autoimmune mechanisms, with unknown etiology. The joint disease dominates the clinical picture, extra-articular affection as serositis, subcutaneous nodules, keratoconjunctivitis sicca and rheumatoid vasculitis may be prominent, dominant, or life-threatening. Production of rheumatoid factors which are autoantibodies is a major immunologic abnormality in rheumatoid arthritis.
Seventy percent of patients with rheumatoid arthritis are RF positive by latex agglutination test but this percentage increases to 90% when ELISA assay is used.
OBJECTIVES:
The aim of this work was to study the relation between the serum level of rheumatoid factor IgA and IgM versus the disease activity and disability index in patients with rheumatoid arthritis.
METHODS:
The present study included 30 patients with rheumatoid arthritis. All patients were subjected to: thorough history taking, thorough clinical examination including joint examination, assessment of disease activity by disease activity score 28 with 4 variables (DAS 28), assessment of functional status by health assessment questionnaire disability index (HAQ-DI), radiological assessment for detection of erosions and laboratory investigations which include ESR, CRP and RF IgA and RF IgM by using ELISA assay.
RESULTS:
In this study, 66.7% (n=20) of the patients were seropositive by latex agglutination test. This percentage increased to 90% (n=27) and 96.7% (n=29) seropositive for RF IgA and RF IgM measured by ELISA assay, respectively.
In the present study, RF IgA and RF IgM were positively correlated with 28 tender joint count, 28 swollen joint count, patient’s global assessment of disease activity, DAS 28, pain severity assessment and HAQ-DI. Further more; DAS 28 was positively correlated with HAQ-DI. On comparing patients with mild disease activity to those with moderate disease activity (according to DAS 28) and patients with mild disease activity to those with severe disease activity, there was a significant difference in RF IgA or RF IgM titres. On comparing patients with mild functional disability to those with moderate functional disability (according to HAQ-DI), there was a significant difference in RF IgA or RF IgM titres. However, on comparing patients with mild functional disability to those with severe functional disability (according to HAQ-DI), there was a significant difference in RF IgA titres.
In the present study, RF IgA and RF IgM titres were positively correlated with ESR. RF IgA and RF IgM were associated with joint erosions and extra-articular manifestations especially rheumatoid nodules and keratoconjunctivitis sicca.
CONCLUSIONS:
From this study, we concluded the following:
1. Ninety percent of patients with RA were RF IgA positive with the use of ELISA assay.
2. Ninety seven percent of patients with RA were RF IgM positive with the use of ELISA assay.
3. Patients who were seropositive for both RF IgA and RF IgM had higher disease activity and functional disability than patients who were seropositive for only RF IgA or seropositive for only RF IgM only.
4. RF IgA and RF IgM were useful markers for disease activity and for the prognosis of RA. Increased serum level of RF IgA and RF IgM were associated with more severe joint involvement and with extra-articular manifestations, thus those patients need a more aggressive therapeutic strategy.