Failure to show mycoplasmas and cytopathogenic virus in rheumatoid arthritis

Area of Science:

• Rheumatology
• Microbiology
• Infectious Diseases

Background:

• Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation.
• The potential role of microorganisms, such as mycoplasmas and bacterial L-forms, in the pathogenesis of RA remains an area of investigation.

Purpose of the Study:

• To investigate the presence of mycoplasmas, bacterial L-forms, and viruses in synovial fluid and tissue from patients with rheumatoid arthritis.
• To determine if these microorganisms play a direct role in the development or progression of rheumatoid arthritis.

Main Methods:

• Synovial needle biopsies, joint aspirates, and open-operation joint tissue from 41 rheumatoid arthritis patients were analyzed.
• Specimens were inoculated onto PPLO media, L-form medium, and cell cultures to isolate potential pathogens.
• A similar analysis was performed on samples from nine patients with Reiter's disease for comparison.

Main Results:

• No mycoplasmas, bacterial L-forms, or cytopathogenic viruses were detected in the rheumatoid arthritis patient samples.
• One isolate of Mycoplasma hominis type 1 was identified in a knee joint biopsy from a patient with Reiter's disease.
• Contamination by mycoplasmas and bacterial L-forms was noted in some cell cultures and media batches, respectively.

Conclusions:

• The findings suggest that known strains of mycoplasma and bacterial L-forms do not play a direct role in early or established cases of rheumatoid arthritis.
• Further research may be needed to explore other potential microbial agents or pathogenetic mechanisms in rheumatoid arthritis.
• The study highlights the importance of rigorous quality control to prevent microbial contamination in laboratory investigations.