Osteoarthritis/Rheumatoid/Gout Flashcards
Etiopathogenesis of Osteoarthritis
Most common joint disease and a leading cause of disability in the elderly
Sine qua non is hyaline cartilage loss
Risk Factors for OA
- Age (most important)
- Obesity
- repeated joint use
Manifestations of OA
Activity-related
starting as episodic and progressing continuously with accompanying brief morning stiffness (<30 min) that gradually resolves
Commonly affected Joints
- Cervical
- spine
- lumbosacral
- spine
- Hip
- Knee
- 1st MTP
- distal
- proximal IPs
- base of the thumb
Buckling of the knees may occur due to weakness of muscles crossing the joint
Diagnostics for OA
No blood tests is indicated
Synovial fluid analysis
Management of OA
NON-PHARMACOLOGIC
- Exercise with brief periods of rest
- Weight management (wt loss to 5kg = 50% pain reduction)
- Correction of possible misalignment
- Acupuncture
- Oral standardized
- ginger preparation
- Surgery
Pharmacologic Management for OA
- Non-opiod analgesics
- Opiod-like analgesics
- Traditional NSAIDs
- Oral COX-2 inhibitors
- Intraarticular injections
- Hexosaminases
- Capsaicin
NON-opiod analgesics
Paracetamol 500 mg up to QID
- Initial treatment
Modulates the endogenous cannabinoid system in the brain
Can prolong half life of warfarin
Opiod Analgesics
Tramadol 50-100 mg q4-q6
Binds to the u-opiod receptor
SE: Dizziness, sedation, nasuea/vomiting, Urinary retention, constipation, dry mouth
Traditional NSAIDs
Suppress inflammation by ihibiting both COX-1 and COX-2 activity
Naproxen 375-500 mg BID, taken with food
SE: GI ulceration and bleeding, edema, renal insufficiency
Diclofenac gel 1% gel, 4 g QID Should be rubbed onto joint
- Skin irritation common
- Avoid if with renal disease
Oral COX-2 inhibitors
Inhibits COX-2 activity only
- Celecoxib 100-200mg QD-BID
- Eterocoxib
SE: Increased risk for stroke and MI
Capsaicin
Bind to the vanilloid receptor sybtype 1 (TRPV1) thereby modulating pain sensations.
0.025%-0.075% cream 3-4x day
Can irritatemucous membrane
Etiopathogenesis of Gouty Arthritis
Metabolic disease that usually affects men (30s onwards) and postmenopausal women
- Increased body urate pool with hyperuricemia
- Urate overproduction
- Urate Underexcretion
Precipitants of Hyperuricemia (Gouty)
- Dietary excess
- Trauma,
- surgery
- Excessive ethanol ingestion
- Hypouricemic therapy
- Serious comorbid illnesses such as stroke and MI
Manifestations of Gouty Arthritis
- Acute arthritis usually initially affecting MTP of the first toe (PODAGRA) or ankle or knee, followed by episodes of acute mono-or oligoarthritis and finally chronic nonsymmetric synovitis with topaceous deposits
- Inflamed Heberden’s and Bouchard’s nodes
- Initial attacks mimic cellulitis, subside spontaneously over 3-10 days, and have varying asymptomatic periods until the next attack
Asymptomatic hyperuricemia
Hyperuricemia in the absence of gouty arthritis and uric acid nephrolithiasis
Hyperuricemia
- Men: >7 mg/dL
- Female: >6 mg/dL
Acute Gouty Arthritis
Urate crystal in the joint fluid, and/or
Presence of six of the 12 clinical laboratory, and Xray phenomenon
- Max. Inflammation developed within 1 day
- More than 1 attack of acute arthriitis
- Monoarticular arthritis
- Redness over joints 1st MTP joint pain or swelling
- Unilateral first MTP joint attack
- Unilateral tarsal joint attack
- Suspected Tophus
- Hyperuricemia
- Asymmetric swelling within a joint on X-ray
- Subcortical cysts without erosions on x-ray
- Negative organisms on culture of joint fluid during attack
Intercritical (interval) Gout
Asymptomatic periods between gouty attacks
Chronic Tophaceous gout
- occurs in untreated gouty arthritis
- Low grade inflammation of joints with sporadic flares
- Joint deformities occur due to deposition of urate crystals, forming visible tophi
24-h uric acid urine collection
- >800mg/24h (over producers)
- <600 mg/24 h (under excretors)
Treament goal for gout:
Uric acid <6mg/dL
Medical management of Acute Attacks
Recommended first-line options
- Colchicine
- NSAIDs
- Oral Costicosteroid
- Articular aspiration and injection of steroids
Colchicine
1 mg LD within 12 hours of flare onset followed 1 hour later by 0.5 mg; or TID unil flare subsides.
Inhibits microtubule polymerization and neutrophil activity/motility, giving its anti-inflammatory effect
Avoid in patients with severe renal impairment and those receiving CYP3A4 inhibitors
NSAIDs in acute flares of GA
- Celcoxib 400 mg BID
- Diclofenac 50 mg TID
- Etoricoxib 120 mg OD
- Indomethacin 25-50 mg TID
- Naproxen 500mg BID
Steroids
Prednisolone 30-35 mg/day (or its equivalent for 3-5 days)`
Anakinra
100 mcg/day SC for 3-5 days
IL-1 Blocker
Indications for Therapeutic Arthrocentesis
- Unable to take oral medications
- Have only 1-2 actively inflamed joints
- Ready access to a clinician with expertise in arthrocentesis
- Can be performed immediately prior to injecting intraarticular medications
Flare Prophylaxis for Gouty Arthritis
Recommended during the first 6 months of ULT or until serum uric acid is <6 mg/dL
Colchicine 0.5-1 mg/day
Urate lowering therapy
Indicated in all patients with
- recurrent flares (>2/year),
- tophi
- urate arthropathy,
- and/or nephrolithiasis
Should be started close to time of first diagnosis in
- patients <40 years old
- SUA >8 mg/dL with commorbidities
Target lifelong SUA: <6 mg/dL
Lower target: <5 mg/dL
Allopurinol
Inhibits xanthine oxidase blockng uric acid production
Initial low dose: 100 mg/day and increased at 100 mg increments every 2-4 weeks
Usual dose: 300 mg/day