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Mycoplasmas and 'diphtheroids' in rheumatoid arthritis

S M Stewart, W H McBride

    Rheumatology
    |January 1, 1975
    PubMed

    Insights

    Conventional mycoplasmas were not found in rheumatoid arthritis patients, suggesting they do not cause the disease. However, diphtheroid organisms were frequently detected in rheumatoid joints, indicating a potential role in rheumatoid arthritis pathogenesis.

    Area of Science:

    • Rheumatology
    • Microbiology
    • Immunology

    Background:

    • Rheumatoid arthritis (RA) is a chronic inflammatory disease with an unknown etiology.
    • The role of microbial agents, specifically mycoplasmas and diphtheroids, in RA pathogenesis remains debated.

    Purpose of the Study:

    • To investigate the presence and potential role of mycoplasmas and diphtheroid organisms in patients with rheumatoid arthritis.
    • To determine if these microorganisms are associated with the synovial inflammation characteristic of RA.

    Main Methods:

    • Culturing synovial membranes and fluids from RA patients and controls for microbial isolation.
    • Utilizing various culture media and techniques to detect mycoplasmas and diphtheroids.
    • Measuring serum agglutination titers against specific microbial antigens (C. acnes and an isolated diphtheroid) in RA patients.

    Main Results:

    • Conventional mycoplasmas were not isolated from any RA patient specimens.
    • Diphtheroid organisms were isolated from 27-30% of RA synovial specimens, but not from non-RA controls.
    • Elevated agglutination titers to C. acnes and the isolated diphtheroid were significantly more common in RA patients' sera.

    Conclusions:

    • Mycoplasmas are unlikely to be involved in the etiology of rheumatoid arthritis.
    • Diphtheroid organisms are present in the joints of RA patients.
    • The presence of diphtheroids and the immune response to them suggest a potential, yet unestablished, role in rheumatoid arthritis.

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