Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003873 (rheumatoid arthritis)
 53,068 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rheumatoid factor (RF) may play a role in sustaining the inflammatory events and tissue damage in rheumatoid arthritis (RA). However, many serum RF have greater specificity for rabbit IgG than for human IgG, thus raising questions about RF pathogenicity in RA. Serum RF also has specificity for human IgG subclasses 1, 2 and 4, but not for IgG3. The synovium is central to the pathology of RA; thus, RF made there may have greater pathogenicity than serum RF. We examined the specificity of 19S IgM RF in an RF plaque forming cell assay (RF-PFC) using RA synovial cells (RSC). We found that: (1) RSC produced greater numbers of RF-PFC/10(6) cells than did RA peripheral blood mononuclear cells (PBM); (2) RSC RF-PFC had greater specificity for human than for rabbit IgG compared to autologous serum RF; (3) RSC RF had significantly greater specificity for human IgG3 relative to autologous serum RF. In contrast, RSC RF and autologous serum RF had the same relative specificities for polyclonal human IgG, IgG1, IgG2, and IgG4. Thus, the specificity of much of the RF synthesized by RSC differed from serum RF. The potential pathogenic significance of these observations is discussed.
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PMID:Comparative specificities of serum and synovial cell 19S IgM rheumatoid factors in rheumatoid arthritis. 390 Mar 91

A one day enzyme immunoassay for the detection of rheumatoid factors of the IgG, IgM, and IgA class is described. The assay utilizes rabbit IgG as solid-phase reactant and the biotin-avidin interaction for the coupling of enzyme to indicator antibody. Three different indicator antibodies discriminated effectively between rheumatoid arthritis patients and normal subjects. F(ab')2 fragments of goat antibodies were found best suited for the test. Rheumatoid factor activity was expressed in U/ml by comparing samples to an internal standard, which was related to the WHO international reference serum for rheumatoid arthritis. Rheumatoid factor activity (U/ml) in the IgM-specific assay showed a close correlation to the latex agglutination titer. Avidity indices estimated from the slopes of the dose response curves of test sera were significantly higher for rheumatoid arthritis patients than for a group of healthy persons, indicating a higher avidity of the rheumatoid factors in the patients' sera.
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PMID:Analysis of rheumatoid factors by a biotin-avidin based isotype-specific ELISA. 408 17

Sera from 53 Nigerian patients satisfying the American Rheumatism Association criteria for a diagnosis of definite or probable rheumatoid arthritis and sera from sick and healthy Nigerian controls were tested for rheumatoid factor, autoantibodies, and immunoglobulin levels. Rheumatoid factor and autoantibodies were found no more frequently in patients with rheumatoid arthritis than in controls. These findings confirm the clinical impression that Nigerian patients with polyarthritis satisfying the criteria for a diagnosis of rheumatoid arthritis differ from Caucasian patients with the disease in a number of important respects. They suggest that either these patients do not have rheumatoid arthritis but a distinct clinical syndrome or that in Nigeria the course of rheumatoid arthritis is modified by genetic or environmental factors.
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PMID:Low incidence of rheumatoid factor and autoantibodies in Nigerian patients with rheumatoid arthritis. 541 47

Twenty-seven patients with rheumatoid arthritis entered and 20 completed a one year double blind trial in which the effects of alclofenac 1 g 3 or 4 times daily were compared with gold injections 50 mg weekly intramuscularly to 1 g then 50 mg monthly. Previous anti-inflammatory medication was continued. Assessments were done every 3 months. On both drugs there was a delayed continued improvement over at least the first 6 months in mean pain scores, morning stiffness, grip strength, articular index and an overall grading system. The mean ESR fell markedly in patients on gold, but in those on alclofenac it showed no consistent change. Several measurements showed improvements statistically compared with initial values in both groups after 6 months. Rheumatoid factor, and hand and feet X-rays, were not influenced by either treatment. Side effects were rather similar on both drugs, and 4 patients in each group developed a rash.
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PMID:A double-blind one year clinical trial comparing alclofenac with gold in rheumatoid arthritis. 613 90

This solid-phase immunoassay for detection of rheumatoid factor involves a specially prepared indium surface that renders protein layers visible and therefore does not require tagged protein. Using appropriate discriminatory values, we found agreement with results of a standard latex-fixation test in controls and patients with rheumatoid arthritis. About half of the patients with rheumatoid arthritis that were seronegative by this latex fixation test had positive tests by the present assay. Rheumatoid factor of both the IgM and IgA class may be easily assessed.
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PMID:A new assay for rheumatoid factor. 637 53

Thirty-three patients with early arthritis, 28 of whom developed classical/definite rheumatoid arthritis (RA), were followed up for two to four years. Rheumatoid factor (RF) levels of the IgM, IgA, and IgG isotypes were measured in serum and synovial fluid by an ELISA technique developed in our laboratory. All seven patients who presented with raised IgA RF developed erosions of their hands and wrists. This was significantly different from the remaining 26. By contrast none of the five patients who presented with isolated elevation of IgM RF developed erosive disease. The patients with raised IgA RF needed significantly more treatment with 'specific' drugs than the remaining 26. It is suggested that the detection of IgA RF in early RA indicates poor prognosis, justifying a more aggressive treatment at an early stage.
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PMID:Prospective study of early rheumatoid arthritis. I. Prognostic value of IgA rheumatoid factor. 649 59

Juvenile rheumatoid arthritis (JRA) is best defined as the condition of chronic synovitis in children. Such chronic childhood arthritis probably includes several distinct disease processes. Recognizable subgroups are systemic-onset disease (20%), rheumatoid factor-negative polyarthritis (25%), rheumatoid factor-positive polyarthritis (5%), pauciarthritis associated with antinuclear antibodies and chronic iridocyclitis (30%-35%), and pauciarthritis associated with sacroiliitis and HLA-B27 (10%-15%). Rheumatoid factor-positive polyarthritis appears to be the childhood equivalent of classic adult rheumatoid arthritis; the pauciarthritis associated with HLA B27 appears to be closely related to the spondyloarthropic diseases. Although there are no diagnostic laboratory tests, various subgroups differ in immunogenetic findings as well as in clinical appearance and prognosis. A wide variety of conditions (infectious diseases, childhood malignancies, genetic and congenital conditions, and noninflammatory musculoskeletal lesions) can mimic JRA and must be considered in the differential diagnosis. The outlook for most children with JRA is good; fewer than 20% have progressive destructive disease (generally those with rheumatoid factor-positive or systemic-onset disease). Therapy rests on the conservative use of antirheumatic drugs, active physical therapy programs, maintenance of activities, and attention to the psychosocial development of the whole child. Orthopedic surgery can be helpful, particularly in the rehabilitation of children who have suffered severe joint destruction or deformity. Combined orthodontic and oral surgery therapy can restore function and appearance for young people with the micrognathia of temporomandibular joint involvement.
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PMID:Chronic arthritis in children. Juvenile rheumatoid arthritis. 660 49

Thirty-nine black African patients were seen with probable, definite or classical rheumatoid arthritis (RA); 32 of these were seen in a prospective study out of a total of 15 834 new patients 15 years and older at presentation seen in a 12-month period. The diagnosis was based on the American Rheumatism Association criteria for RA or the Rome criteria for inactive RA. The high incidence of severe disease as well as the occurrence of advanced disease in young patients is notable. 80% of the patients came from rural areas. Radiological lesions were found in 74% and serological abnormalities in 92%. Rheumatoid factor (RF) was found to be positive in 12% of an age and sex matched control group and in 19% of a group of patients suffering from tuberculosis.
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PMID:Rheumatoid arthritis in Lesotho. 669 15

Three patients with cutaneous vasculitis and one patient with digital gangrene had a negative or equivocal test for cryoglobulins but a positive result in a modified assay for cryoproteins ( hypocryoglobulins [ HGs ]) in which serum is rendered hypotonic by dilution with an equal volume of distilled water before incubation in the cold. Each cryoprecipitate contained a mixture of immunoglobulins, and in two instances, a monoclonal component was demonstrated. Rheumatoid factor activity was found in two precipitates. All four patients improved with plasmapheresis, and two subsequently responded to alkylating agents. Seven patients with conventional cryoglobulins had precipitation from diluted serum as well, but none had a substantial increase in precipitation in the HG assay. Only two of five patients with seropositive rheumatoid arthritis had abnormal levels of HG. Hypocryoglobulins are a new category of abnormally insoluble serum proteins, probably closely related to conventional cryoglobulins, which are readily detected in a simple precipitation assay.
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PMID:'Hypocryoglobulins'. Enhanced cryoprecipitation from hypotonic serum in patients with vasculitis. 673 99

Different immunoglobulin classes, complement factors, complement fixation and rheumatoid-factor activity in rheumatoid synovial membranes of 16 patients were studied. After pepsin digestion of tissue sections, greatly increased numbers of plasma cells were able to bind human gamma globulin. In addition we found after the pepsin digestion more IgG and less IgM in the tissues. The results gave evidence of intracellular blocking of rheumatoid factor activity, due to IgG-IgG rheumatoid factor complexes or self associated rheumatoid factors. Additional evidence of such plasma cell complexes was obtained by observing an in vitro fixation of the complement. With the same methods we studied 3 patients whose synovial membranes had been surgically removed not later than 6 months after the onset of evident symptoms and who developed rheumatoid arthritis within an observation period of 2 years. As a result we found a small production of predominantly M and G immunoglobulins. The rheumatoid factors were also found in a small degree. Rheumatoid factor activity can be revealed only in a little number of plasma cells by pepsin digestion of tissues. In the serum we can't find more rheumatoid factor activity after pepsin digestion in the latex test. The immunofluorescence for detection of rheumatoid factors in tissues is a practicable method and important for the differential diagnosis of joint diseases.
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PMID:[Immunohistochemical detection of tissue-bound rheumatoid factors (author's transl)]. 678 88


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