This Friday at Friday school, in addition to the amazing journal fight club on the use of plasmapheresis for ANCA-associated vasculitis affecting the kidney (see Justin’s separate, awesome post), we ALSO learned about diagnosing and managing common musculoskeletal complaints (with Dr. Ken Vitale from sports medicine), crystal arthropathy (with gout guru and guideline author Dr. Robert Terkeltaub) and rheumatoid arthritis (with gifted clinician-educator Dr. Katherine Nguyen). YAY Rheumatology! The “smart guy” consult for multi-system disease!
Here are a few key take home points!
- In the world of sports medicine age >40 (and in some cases >35) is OLD, and impacts the epidemiology of common causes for knee pain
- Iliotibial band syndrome presents with diffuse, poorly localized lateral knee and distal thigh pain at the end of exercise involving knee flexion and extension . Running outdoors or downhill may worsen symptoms. On exam, there is often tenderness ~ 2-3 cm proximal to the lateral femoral condyle. Treat with abstinence from inciting activity, ice, followed by gradual return to activity, stretching, strengthening, and local massage.
- Consider radial tunnel syndrome in patients with burning or numbness on the outside forearm and elbow, just distal to the lateral epicondyle.
- Gold standard for diagnosis of acute gout is negatively birefringent, needle-like uric acid crystals within neutrophils in joint fluid.
- Colchicine, NSAIDs, and glucocorticoids (intra-articular or systemic) are all options for treatment of acute gout; consider patient comorbidities (diabetes, kidney disease) and drug interactions when choosing.
- The American College of Rheumatology recommends a “treat-to-target” approach, with a target serum urate <6.0 mg/dL . Allopurinol, started at a low dose (100mg/day for normal kidney function) and titrated up, is the 1st line therapy; check an HLAB58*01 first in those from high risk ethnic groups (Black & Asian) to avoid severe hypersensitivity skin reaction. Start anti-inflammatory prophylaxis to prevent flares.
Rheumatoid Arthritis (RA)
- The most useful lab tests in the diagnosis of rheumatoid arthritis (RA) are rheumatoid factor and anti–cyclic citrullinated peptide (CCP) antibodies; anti-CCP antibodies have a specificity of 95% for RA.
- Methotrexate is the anchor drug in rheumatoid arthritis; it is used as monotherapy and as a component of combination therapy.
- Tumor necrosis factor α inhibitors are the most frequently used biologics to treat rheumatoid arthritis; they have a rapid onset of action and synergy with methotrexate.