Arthritis, Rheumatoid (RA)

Arthritis, Rheumatoid (RA) is a topic covered in the 5-Minute Clinical Consult.

To view the entire topic, please or .

5-Minute Clinical Consult (5MCC) app and website powered by Unbound Medicine helps you diagnose and manage 900+ medical conditions. Exclusive bonus features include Diagnosaurus DDx, 200 pediatrics topics, and medical news feeds. Explore these free sample topics:

-- The first section of this topic is shown below --

Basics

Description

  • Chronic systemic autoimmune inflammatory disease with symmetric polyarthritis and synovitis
  • Progressive chronic inflammation leads to large and small joint destruction, deformity, decline in functional status, and premature morbidity/mortality.
  • System(s) affected: musculoskeletal, skin, hematologic, lymphatic, immunologic, muscular, renal, cardiovascular, neurologic, pulmonary

Geriatric Considerations
Decreased medication tolerance; increased incidence of hydroxychloroquine-associated maculopathy and sulfasalazine-induced nausea/vomiting, NSAID-induced gastric ulcers, and corticosteroid-induced diabetes and osteoporosis

Pregnancy Considerations
  • Use effective contraception in patients taking disease-modifying antirheumatic drugs (DMARDs).
  • Methotrexate, leflunomide, cyclophosphamide, and cyclosporine are teratogenic. Sulfasalazine and hydroxychloroquine are safe to use during pregnancy and breastfeeding.
  • 50–80% of patients improve during pregnancy because of immunologic tolerance. Most relapse in 6 months after delivery. First episode may occur in pregnancy or postpartum.

Epidemiology

Incidence
  • 25 to 30/100,000 for males
  • 50 to 60/100,000 for females
  • Peak age at onset is 35 to 50 years.

Prevalence
1% of the U.S. population

Etiology and Pathophysiology

  • An insult (e.g., infection, smoking, trauma) precipitates an autoimmune reaction activating antibody-complement complexes, resulting in endothelial activation, synovial hypertrophy, and joint inflammation/damage.
  • Pathogenesis is mediated by abnormal B- and T-cell interactions and cytokine overproduction (TNF, interleukin-6 [IL-6]).
  • Multifactorial disease with genetic, host (hormonal, immunologic), and environmental (socioeconomic, smoking) factors

Genetics
  • Rheumatoid arthritis (RA) is 50% attributable to genetic causes. HLA-DR4 is a shared epitope in >50% of cases.
  • Monozygotic twin concordance is 15–20%, suggesting nongenetic factors also contribute.
  • Individuals with HLA-DR4 and DRB1, and mutations in STAT4, CD40+ have increased relative risk.

Risk Factors

  • First-degree relatives have 2- to 3-fold increased risk.
  • Smokers have elevated relative risk. Smoking is associated with an increased risk of developing anticitrullinated protein antibody (ACPA)-positive antibodies.
  • Pregnancy and breastfeeding lowers risk up to 50%.
  • Women affected 3:1; difference diminishes with age.

Commonly Associated Conditions

Accelerated atherosclerosis, pericarditis, amyloidosis, Felty syndrome (RA, splenomegaly, neutropenia), interstitial lung disease, pulmonary nodules, rheumatoid nodules, vasculitis, lymphomas, carpal tunnel syndrome

-- To view the remaining sections of this topic, please or --

Basics

Description

  • Chronic systemic autoimmune inflammatory disease with symmetric polyarthritis and synovitis
  • Progressive chronic inflammation leads to large and small joint destruction, deformity, decline in functional status, and premature morbidity/mortality.
  • System(s) affected: musculoskeletal, skin, hematologic, lymphatic, immunologic, muscular, renal, cardiovascular, neurologic, pulmonary

Geriatric Considerations
Decreased medication tolerance; increased incidence of hydroxychloroquine-associated maculopathy and sulfasalazine-induced nausea/vomiting, NSAID-induced gastric ulcers, and corticosteroid-induced diabetes and osteoporosis

Pregnancy Considerations
  • Use effective contraception in patients taking disease-modifying antirheumatic drugs (DMARDs).
  • Methotrexate, leflunomide, cyclophosphamide, and cyclosporine are teratogenic. Sulfasalazine and hydroxychloroquine are safe to use during pregnancy and breastfeeding.
  • 50–80% of patients improve during pregnancy because of immunologic tolerance. Most relapse in 6 months after delivery. First episode may occur in pregnancy or postpartum.

Epidemiology

Incidence
  • 25 to 30/100,000 for males
  • 50 to 60/100,000 for females
  • Peak age at onset is 35 to 50 years.

Prevalence
1% of the U.S. population

Etiology and Pathophysiology

  • An insult (e.g., infection, smoking, trauma) precipitates an autoimmune reaction activating antibody-complement complexes, resulting in endothelial activation, synovial hypertrophy, and joint inflammation/damage.
  • Pathogenesis is mediated by abnormal B- and T-cell interactions and cytokine overproduction (TNF, interleukin-6 [IL-6]).
  • Multifactorial disease with genetic, host (hormonal, immunologic), and environmental (socioeconomic, smoking) factors

Genetics
  • Rheumatoid arthritis (RA) is 50% attributable to genetic causes. HLA-DR4 is a shared epitope in >50% of cases.
  • Monozygotic twin concordance is 15–20%, suggesting nongenetic factors also contribute.
  • Individuals with HLA-DR4 and DRB1, and mutations in STAT4, CD40+ have increased relative risk.

Risk Factors

  • First-degree relatives have 2- to 3-fold increased risk.
  • Smokers have elevated relative risk. Smoking is associated with an increased risk of developing anticitrullinated protein antibody (ACPA)-positive antibodies.
  • Pregnancy and breastfeeding lowers risk up to 50%.
  • Women affected 3:1; difference diminishes with age.

Commonly Associated Conditions

Accelerated atherosclerosis, pericarditis, amyloidosis, Felty syndrome (RA, splenomegaly, neutropenia), interstitial lung disease, pulmonary nodules, rheumatoid nodules, vasculitis, lymphomas, carpal tunnel syndrome

There's more to see -- the rest of this entry is available only to subscribers.