Crystal-Induced Arthritis Flashcards
(34 cards)
What are the characteristic features of crystal-induced arthritis?
- acutely painful
- monoarticular (one joint)
- remits spontaneously (intermittent)
*** What crystal is associated with gout?
- monosodium urate monohydrate
*** What crystal is associated with pseudogout?
- calcium pyrophosphate dihydrate
What is gout?
- metabolic disease characterized by hyperuricemia, which manifests by acute arthritis (tophi) or renal stones.
Is gout a men’s or lady’s disease?
- mens
What is at the center of purine metabolism?
- inosinic acid
What medication blocks xanthine oxidase?
- allopurinol= prevents production of uric acid.
Why has prevalence of gout doubled in the last 15 years?
- longevity (increase in DM and CHF)
- use of ASA and thiazide diuretics
- HTN
- increase in caloric intake
How do we classify gout?
- primary (idiopathic) or specific enzyme abnormalities: G6Phosphatase, HGPRTase, or PRPP synthetase
- secondary (nucleic acid turnover
What is Lesch-Nyhan syndrome?
- total deficiency of HGPRTase
What clinical disorders lead to purine overproduction?
- myeloproliferative diseases
- lymphoproliferative diseases
- polycythemia vera
- malignancies
- hemolysis
- psoriasis
- obesity
What is a normal uric acid level?
- 6
What drugs can decrease clearance of uric acid?
- thiazide diuretics
- ethanol
- salicylates
- ethambutal
- pyrazinamide
- levadopa
- laxatives
Why does gout like the big toe?
- coldest joint in the body (uric acid accumulates at lower temperatures)
What is a tophus?
- collection of urate in the soft tissue.
How can you differentiate a gout tophus from an RA nodule?
- stick a needle in it, and look for crystal of uric acid.
What are the clinical manifestations of gout?
- acute intermittent arthritis (podagra= pain in big toe)
- chronic gouty arthritis (tophaceous)
- renal presentation (uric acid lithiasis; radiolucent).
- gouthy nephropathy, HTN/proteinuria).
- asymptomatic hyperuricemia
Are uric acid crystals strongly negatively birefringent?
- YES
* remember GYB (gout goes yellow to blue).
What radiologic finding is pathognomonic for gout?
- overhanging edge sign
How do you diagnose gout?
- arthrocentesis (synovial fluid crystals)
- uric acid calculi
- tophaceous deposits
Which drug would you use to make a presumptive diagnosis of gout?
- COLCHICINE!!!
Why don’t we use colchicine to treat gout anymore?
- bc 80% of pts will get diarrhea and dysentery
- How do we treat acute arthritis due to gout?
- NSAIDs (don’t use aspirin, bc it will raise uric acid).
- short course of steroids
How do we treat chronic gout?
- uricosuric drugs
- allopurinol
