NOTE: this is a USMLE Consult-"inspired" question, so look away if you plan on using USMLE Consult as a measure of your progress.
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A 50-year-old man has severe pain at the base of his left great toe, around the forward portion of the arch. The first metatarsophalangeal joint of his left foot is tender, markedly inflamed, and erythematous. Laboratory studies show a serum uric acid level of 10.4 mg/dL. A 24-hour urine specimen contains 550 mg of uric acid. Light microscopy of a synovial aspirate shows the presence of monosodium urate crystals. The most appropriate treatment for this patient’s arthritic pain is:
A. allopurinol
B. aspirin
C. colchicine
D. probenecid
E. sildenafil
Actually NSAIDS like indomethacin are considered First line in acute gout, and colchicine second line because of its side effects nausea, vomit, and diarrhea.
I would say Colchicine,
but I ve heard Goljan saying that its not used anymore, use allopurinol.... (His audio is 10 years old) But Jenkins in DIT 2008 said - Colchicine for sure (till patient craps himself)
Pharm flashcards from conrad fisher say Colchicine too (for acute gout ofcourse)
Can't give allopurinol in an acute gouty arthritis, will only precipitate the crystals, and increase inflammation.
New guide lines and UW say acute gout NSAID 1st line Colchicine 2nd line and steroids if the two mentioned above are contraindicated like renal failure.
thats not the correct reason of not giving allopurinol for acute gout
the actual reason is that allopurinol only stops further production of uric acid by inhibiting xanthine oxidase; has no effect on already precipitated crystals & will have a slow onset of action, so will be ineffective in acute gout
Colchicine is used in ACUTE gout because it binds to tubulin and decreases microtubular polymerization and also decreases LTB4 & leukocyte and granulocyte migration.
Allopurinol and Probenecid are used in Chronic gout because these are prodrugs that are converted by xanthine oxidase to alloxanthine which then inhibits the enzyme xanthine oxidase itself. They're known as "suicide substrates". By inhibiting XO they decrease purine metabolism which decreases uric acid. Probenecid inhibits the proximal tubular reabsorption of urate.
So as you can tell, that acutely allopurinol and probenecid have no use because their mechanism of action takes a while to work! That's why its good to use them in chronic gout or prophylaxis.
Colchicine however directly has action on LTB4 (neutrophil migration, inflammation) and Leukocyte and granulocyte migration .. therefore it helps reduce inflammation and reduces pain!
Colchicine is used in ACUTE gout because it binds to tubulin and decreases microtubular polymerization and also decreases LTB4 & leukocyte and granulocyte migration.
I thought Colchicine binds microtunules in neutrophils and prevents their migration (M phase of the cell cycle), and Bleomycin is the one to bind microtubules (G2)
The question would normally say that the patient comes in to the emergency with severe pain...Or else if it was chronic he would already be on a medication in the question stem. When gout arises there is pain, so its not like the patient will not go to the doctor! )
colchicine is the right anwer...also probenecid can not be used due to competing uric acids secretion
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