Rheumatoid Factor
Also written as RF.
Laboratory studies show that her rheumatoid factor and cyclic citrulinnated peptide serologic titers are markedly elevated, but her antinuclear antibody test is negative.
What our notes say
- Laboratory studies show that her rheumatoid factor and cyclic citrulinnated peptide serologic titers are markedly elevated, but her antinuclear antibody test is negative. (Immunopathology complete mcqs — Past Paper Questions & Answers)
- Rheumatoid nodules and rheumatoid factor are usually absent (General Pathology MCQs: Fixatives, FNA, Endocrine & ARDS)
- Cause-finding: HIV test, immunoglobulins, sweat chloride/CFTR (cystic fibrosis), ciliary function and nasal nitric oxide, Aspergillus IgE and precipitins, rheumatoid factor, alpha-1 antitrypsin. (Bronchiectasis)
- High serum titre of autoantibodies (rheumatoid factor, anti-CCP) (Internal Medicine Rheumatology CAT: 30 MCQs and 5 short answer questions)
- Rheumatoid factor (RF) — IgM and IgA autoantibodies that bind IgG Fc regions; present in 80% of individuals; may be deposited in joints as immune complexes; not specific (can occur without RA) (Mastering Joint Pathology: Arthritis, OA & Joint Anatomy)
- Hepatitis C → chronic antigenaemia → IgM rheumatoid factor production → IgG-IgM cryoglobulin complexes (FSGS & HIV Nephropathy: Causes, Symptoms, Diagnosis & Prognosis)
Study material on Rheumatoid Factor
- Immunopathology complete mcqs
- Internal Medicine Rheumatology CAT: 30 MCQs and 5 short answer questions
- Paediatrics Senior Clerkship end of 2nd semester exam: 4 October 2021, 50 MCQs
- Immunopathology
- Mastering Joint Pathology: Arthritis, OA & Joint Anatomy
Practice questions on Rheumatoid Factor
A 60-year-old woman has 20 years of crippling hand and foot arthritis with ulnar deviation and swan-neck deformities. Rheumatoid factor and anti-CCP are markedly elevated. Rectal biopsy shows Congo red-positive amorphous deposits. Most likely precursor protein?
- Amyloid precursor protein
- Beta-2-microglobulin
- Serum amyloid-associated protein
- Transthyretin
Answer: C. Rheumatoid arthritis → chronic inflammation → elevated SAA (serum amyloid-associated protein) → secondary (reactive, AA) amyloidosis depositing in multiple organs including the rectum. ---