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Gouty Arthritis
Aka: Gouty Arthritis, Gout, Podagra
EpidemiologyMen and post-menopausal women more commonly affected Prevalence : 2% of men over age 30 and women over age 50 yearsIncreasing Prevalence in United States related to Obesity and aging population Incidence of gout attacksUric Acid 7 to 8.9 mg/dl: 0.5% annual Incidence Uric Acid >9 mg/dl: 4.5% annual Incidence
PathophysiologySee Uric Acid See Hyperuricemia Gout occurs when Uric Acid levels exceed solubility limits Monosodium urate crystals deposit in joints, Kidney , and soft tissues Isolated and asymptomatic Hyperuricemia is common and requires no treatment
Risk FactorsMost commonObesity Alcohol useHigh purine diet (meats, seafood) Diuretic therapy including Thiazide Diuretic s Other risksDiabetes Mellitus Hyperlipidemia Hypertension Atherosclerosis Renal insufficiency Myeloproliferative disease
Causes: Triggers for acute gout attacksSee Hyperuricemia See Risk Factors above Recent increase in Alcohol or purine intake Medication use (Allopurinol stopped or started, Diuretic or Chemotherapy started) Acute infection Intravenous Contrast dye exposure
PresentationsMonoarthritis (most common)Acute bursitis Tenosynovitis Acute polyarticular gout
SymptomsAssociated SymptomsChills Fever as high as 104 F (40 C) Severity: Very severe painUnable to bear weight Too painful to put on socks Intollerant to light touch from blankets Region:First Metatarsophalangeal joint of great toe (most common)Known as Podagra Affected in 50% of first gout attacks Mid-tarsal joints Ankle jointsKnee Joint s Characteristics: Joint painExcruciating, crushing type pain Timing: Joint painAcute onset of lower extremity joint pain Wakens patient from sleep
SignsAcuteJoint InflammationErythema, tenderness and swelling at affected joint Pain extends well beyond jointEntire foot involved in some cases Asymmetric joint involvementMay only involve one side with the first attack Skin over joint is tense and shiny ChronicGouty Tophi (develop after >=10 years)Chronic arthritisChronic deposition occurs with recurrent attacks
LabsComplete Blood Count Leukocytosis (may be as high as 40,000 wbc/mm3)Serum Uric Acid increased (Hyperuricemia )Synovial Fluid Exam (critical if Septic Arthritis is considered)Polarizing MicroscopyNegatively birefringent Needle shaped Uric Acid crystals Gram Stain and CultureRule out Septic Arthritis Urine Uric Acid (24 hour collection)
Imaging: Affected joint(s)Xray of affected joint shows asymmetric swelling
Diagnosis: Requires one of the followingMonosodium urate crystals in Synovial Fluid orTest Sensitivity : 84%Test Specificity : 100% Gouty Tophi with urate crystals identified on Nodule aspirate orTest Sensitivity : 30%Test Specificity : 99%Minimum of 6 criteria present from the following listPlain radiograph demonstrates subcortical cysts without Erosion s Plain radiograph demonstrates asymmetric swelling within a jointTest Sensitivity : 42%Test Specificity : 90% First metatarsophalangeal joint tender or swollenTest Sensitivity : 96%Test Specificity : 97% Hyperuricemia Test Sensitivity : 92%Test Specificity : 91%Unilateral first metatarsophalangeal joint arthritis Unilateral tarsal joint arthritis Inflammation peaked within one day Monoarthritis episodeMore than one acute arthritis attack Effected joints with overlying redness Gouty Tophi suspected (but not yet confirmed by aspirate)Synovial Fluid culture negative for organisms during an Acute Monoarthritis attack
Differential DiagnosisSeptic Arthritis (critical to distinguish)!Pseudogout Other conditionsCellulitis Reactive Arthritis Rheumatoid Arthritis Osteoarthritis Neuropathic arthritis (Charcot Joint )
Management: Acute attackNSAID s (any are effective if adequately dosed)Avoid in elderly, renal or liver disease, Heart Failure , or Peptic Ulcer Disease Indomethacin (historically has been preferred NSAID in gout)Start: 50mg orally three times daily for 2-3 days Then: 25mg orally three times daily for 4-10 days Naproxen 500 mg orally twice daily for 4-10 daysSulindac 200 mg orally twice daily for 4-10 days Colchicine Less viable option (too expensive) now that generic preparations were removed from the markethttp://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm227796.htm Use as an alternative agent due to GI toxicity Avoid in severe liver or Kidney disease Requires adjusted dosing in renal disease Consider 0.6 orally daily to twice daily taken as adjunct to NSAID (see above)Most beneficial if started within first 24 hours of attack Corticosteroid sRule-out Septic Arthritis first! Use with caution in Diabetes Mellitus Effective alternative to NSAID s (less risk of peptic ulcer) Systemic agentsIV: Methylprednisolone 40 mg (consider if NPO in hospital) IM: Depo-Medrol 80 to 120 mg single dose IM OralPrednisone 40 mg orally daily for 5 days then Prednisone 20 mg orally daily for 5 days then Prednisone 10 mg orally daily for 5 days Intra-articular Corticosteroid Large single joints and refractory cases to other treatment Avoid exacerbating or unhelpful measuresSee Prevention below Aspirin in small doses aggravates disorderAcetaminophen not helpfulPhenylbutazone risks outweigh any benefitsBone Marrow suppressionAplastic Anemia
Prevention: MedicationsContraindicationsDo not use in acute attack IndicationsRecurrent Gout (>3 gout attacks per year) Tophaceous gout Nephrolithiasis Choice of agent based on 24h Uric Acid secretionOver-producer (Used for under-excreters also)Allopurinol 100-300 mg/dayAdjusted dosing in renal insufficiency See Allopurinol for initiation protocol (start with antiinflammatory agent to prevent triggering gout attack) Febuxostat (pending FDA approval in 2007) Under-ExcreterProbenacid and Sulfapyrazine are now rarely usedAllopurinol used now for both types of gout Probenecid 250 mg PO bid (MAX: 1500mg bid)Sulfapyrazine 50 mg PO bid (MAX: 100mg bid) Concurrently start with prophylaxis, low dose x3-6mo:Colchicine 0.6 mg PO daily to bid for 3-6 months (preferred) orIndomethacin 25 mg PO twice daily for 3-6 months (avoid due to adverse effects)
Prevention: GeneralAdjunctive Uricosuric medicationsLosartan (Cozaar )Fenofibrate (Tricor ) Adjunctive agents to considerDairy products may be protectiveChoi (2004) N Engl J Med 350:1093-1103 Eating cherries lowers serum Uric Acid Jacob (2003) J Nutr 133(6): 1826-9 Coffee lowers gout attack riskHowever significant decrease only at >3 cups/day Choi (2007) Arthritis Rheumatism 56(6): 2049-55 Vitamin C : 500 mg/day lowers Uric Acid 0.5 mg/dlHuang (2005) Arthritis Rheumatism 52(6):1843-7 Avoid provocative factors (See Hyperuricemia )Avoid purine-rich foods (See Purine Content in Food s) Avoid Alcohol ic beverages (especially beer) Avoid Thiazide Diuretic s
Associated Conditions: Other Uric Acid ConditionsUric Acid Nephrolithiasis Asymptomatic Hyperuricemia
CourseGout attack episodes last 5-7 days with or without treatment
ReferencesKlippel (1997) Primer Rheumatic Diseases, p. 230-4 Buckley (1996) Am Fam Physician 54(4): 1232-8 Eggebeen (2007) Am Fam Physician 76:801-12 Harris (1999) Am Fam Physician 59(4): 925-34 McDonald (1998) Postgrad Med 104(6): 117-27 Pittman (1999) Am Fam Physician 59(7):1799-1806 Terkeltaub (2003) N Engl J Med 1647-55