Section 1: Rheumatoid Arthritis, Seronegative Spondyloarthropathies and Osteoarthritis Flashcards
Rheumatoid arthritis presents most often in women > 50. Patients have joint pain and morning stiffness that is symmetrical and in multiple joints of the hands lasting for more than 1 hour in the morning with the symptomatic episode going on for at least 6 weeks. There is often a prodrome of malaise and weight loss, but this is not enough to make a clear diagnosis.
List the symptoms and signs of RA (4 or more of it will define the disease)
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4135-4154). . Kindle Edition.
- Morning stiffness lasting more than 1 hour
- Wrist and finger involvement (MCP, PIP)
- Swelling of at least 3 joints
- Symmetric involvement
- Rheumatoid nodules (not necessary to diagnose RA)
- X-ray abnormalities showing erosions (not necessary to diagnose RA)
- Positive rheumatoid factor or anti-CCP
- C-reactive protein (CRP) or ESR
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4135-4154). . Kindle Edition.
List the other findings in RA:
Cardiac
Lung
Blood
Cardiac
- Pericarditis
- Valvular disease
Lung
- Pleural effusion with a very low glucose level
- Lung nodules
Blood
- Anemia with normal MCV
Nerve
- Mononeuritis multiplex
Skin
- Nodules
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4155-4157). . Kindle Edition.
How is the diagnosis of RA made?
Rheumatoid arthritis is diagnosed with a constellation of physical findings, joint problems, and lab tests. There is no single diagnostic criteria to confirm the diagnosis. There is no single therapy to control and treat the disease
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4158-4177). . Kindle Edition.
A 34-year-old woman presents with pains in both hands for the last few months and stiffness that improves as the day goes on. Multiple joints are swollen on exam. X-rays of the hands show some erosion. What is the single most accurate test?
a. Rheumatoid factor
b. Anti-cyclic citrullinated peptide (anti-CCP)
c. Sedimentation rate
d. ANA
e. Joint fluid aspirate
B. Rheumatoid factor (RF) is present in only 75– 85 percent of patients with rheumatoid arthritis (RA). It can also be present in a number of other diseases; hence, the RF is rather nonspecific. Anti-cyclic citrulinated peptide (anti-CCP) is the single most accurate test for RA. It is > 95 percent specific for RA, and it appears earlier in the course of the disease than the RF. There is nothing specific on joint aspiration to determine a diagnosis of RA.
List the joint findings in RA
- Metacarpophalangeal (MCP) swelling and pain
- Boutonniere deformity: Flexion of the proximal interphalangeal (PIP) with hyperextension of the distal interphalangeal (DIP)
- Swan neck deformity: Extension of the PIP with flexion of the DIP
- Baker’s cyst (outpocketing of synovium at the back of the knee)
- C1/ C2 cervical spine subluxation
- Knee: Although the knee is commonly involved, multiple small joints are involved more commonly over time.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4177-4179). . Kindle Edition.
List the features of Felty syndrome
- Rheumatoid arthritis
- Splenomegaly
- Neutropenia
What is the characteristic anemia in RA?
Normocytic normochromic anemia
List the new alternate diagnostic criteria for RA include
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4185-4198). . Kindle Edition.
- Synovitis (a single joint is enough to diagnose RA)
- RF or anti-CCP
- ESR or CRP
- Prolonged duration (beyond 6 weeks)
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4185-4198). . Kindle Edition.
Tests for swollen joint in CCS
- X-rays
- RF
- Anti-CCP
- CBC
- ESR
- C-reactive protein
- If the case describes a swollen joint with an effusion, aspiration of the joint should also be done to establish the initial diagnosis.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4185-4198). . Kindle Edition.
List the joint spared in RA
The sacroiliac joint is spared in rheumatoid arthritis.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4185-4198). . Kindle Edition.
Which of the following will have the lowest glucose level on pleural effusion?
a. CHF
b. Pulmonary embolus
c. Pneumonia
d. Cancer
e. Rheumatoid arthritis
f. Tuberculosis
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4199-4216). . Kindle Edition.
E. Rheumatoid arthritis has the lowest glucose level of all the causes of pleural effusion described here. Treatment NSAIDs combined with a disease-modifying antirheumatic drug (DMARD) is the standard of care in patients with RA. There is no therapeutic difference among NSAIDs, and you may use ibuprofen for any of the rheumatological diseases described. There is no point in waiting to use a DMARD in a patient with severe RA or anyone with joint erosions. NSAIDs will not delay the progression of the disease. Eliminating an abnormal x-ray as a criterion for diagnosis allows earlier treatment with DMARDs. DMARDs The best initial DMARD is methotrexate. Add others if it is not effective.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4199-4216). . Kindle Edition.
Rx of Rheumatoid Arthritis
- NSAIDs combined with a disease-modifying antirheumatic drug (DMARD) is the standard of care in patients with RA
-
Methotrexate: This is the best-tolerated and most widely used DMARD
- Adverse effects are bone marrow suppression and pneumonitis
- Biological agents (infliximab, adalimumab, etanercept)
- Hydroxychloroquine: Use with mild disease
- Sulfasalazine: This is the same drug that was used in the past for ulcerative colitis. It can suppress the bone marrow.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 4209-4210). Kaplan Publishing. Kindle Edition.
Rheumatoid arthritis
- What test should be done before initiating Rx with TNF inhibitors
- Why does infliximab have to be given with methotrexate?
- Associated with reactivation of latent TB
- Methotrexate prevents anti-infliximab antibody formation
List alternatives to DMARDs
- Rituximab: Anti-CD-20 antibody
- Anakinra: IL-1 receptor antagonist
- Tocilizumab: IL-6 receptor antagonist. Added to methotrexate if it is ineffective
- Leflunomide: Pyrimidine antagonist that is similar in effect to methotrexate, with less toxicity
- Abatacept: Inhibits T-cell activation
- Gold salts: Rarely used because of toxicity, such as nephrotic syndrome
Use the mnemonic “RAT LAG”
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 4226-4231). Kaplan Publishing. Kindle Edition.
What is the place of steroids in the Rx of RA?
Steroids are a bridge to DMARD therapy. They are the answer for an acutely ill patient with severe inflammation.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 4234-4235). Kaplan Publishing. Kindle Edition.