Gout Flashcards
What is gout
A type of arthritis caused by monosodium urate (MSU) crystals
Why is there not a build up of uric acid in other mammals
Other mammals have an enzyme called uricase that metabolizes uric acid to allantoin that is readily eliminated (humans have no uricase)
What factors increase the risk of gout
Age, Increased Scr, Increased BUN, Male gender, high blood pressure, high body weight, alcohol intake, serum uric acid greater than 7 mg/dL, family history
What are the two ways that normal uric acid is eliminated
GI excretion after enzymatic degradation by colonic bacteria (1/3) , Urine excretion (2/3)
What are the two main causes of UNDEREXCRETION of uric acid
CKD and Diabetes
What are 3 purine sources that are used to make nucleic acid or uric acid leading to OVERPRODUCTION
Conversion of tissue nucleic acid to purine nucleotides, De novo synthesis, dietary purine
T/F: High dietary purine intake alone will increase serum uric acid
False: Vast majority of overproduction is increased breakdown of tissue nucleic acids due to increased cell turnover
What medications are associated with getting gout
Salicylates, diuretics, cytotoxic drugs
What causes the pain from GOUT
inflammatory attack due to uric acid deposition mediated by leukocytes
T/F: The most common clinical presentation is in the big toe BUT can be present in other joints such as the feet, knees, hands, or elbows
True
What joint in the big toe is most often affected by gout
Metatarso-phalangeal joint (MTP)
What would be found if aspiration form the synovial fluid was possible for the patient
Urate crystals inside synovial fluid leukocytes, large numbers of polymorphonuclear leukocytes
What are the 11 criteria (need 6) that needs to be met to be diagnosed with gout
More than 1 acute attack of arthritis Exquisite pain involving joint Joint inflammation maximal with one day Oligoarthritis Erythema over involved joints Tophi Podagra (unilateral) Hyperuricemia MSU crystals in joint fluid during attack Joint fluid negative for organisms Asymmetric selling in a join and/or subcortical cysts
What non pharmacological treatment can aid initially for a Gout attack
Ice and joint rest
What is the MOA desired for drugs treating gout acutely, what are the meds, when should they be initiated
Reducing the inflammation/ NSAIDs, corticosteroids, cholchicine/ 24 hours
`T/F: Though indomethacin is the most favored NSAID there is NO evidence that any given NSAID is superior to the others
True
`What cautions/contrainidicatons for using NSAIDs to treat a patient
CHF, CKD, history of GI bleed, asthma, anticoagulation
What is the most potent anti-inflammatory drugs used for resistant cases but could also be used first line
Corticosteriods
What are the corticosteriods that can be given for gout
Prednisone (0.5 mg/kg/day for 2-5 dyas then taper for 7-10 days to prevent rebound attack), Methylprednisolone pack, Triamcinolone acetonide 20-40 mg (intra-articular administration)
What are the adverse effects of corticosteroids
fluid retention and HTN, mood swings, hyperglycemia, infection, GI
What are cautions/contraindications of using corticosteroids
Infection (latent or active), HTN, cirrhosis, CHF
What is the drug that was FDA approved for gout in 2015, what is the FDA approved dose
Colchicine: 1.2 mg (two 0.6 mg tablets) once, then 0.6 mg one hour later
What are tips for colchicine administration
Wait 12 hours to resume prophylactic dose, DON’T take another course within 3 days, CrCl less than 30 do not give another coure for 14 days
What CYP3A4 inhibitors should be monitored when co-administered with colchicine
protease inhibitors, Macrolides (clarithromycin and erythromycin), antifungals (irtraconazole, ketoconazole, flucanozole), non-DHP CCBs (dilitazem and verapmil), grapefruit juice
What p-gp inhibitors should be cautioned when using cochicine
Cyclosporine and Ranolazine
Adverse effects of colchicine
nausea/vomiting, diarrhea. bone marrow toxicity, neurologic loss of reflexes, myopathy, renal dysfunction
What are nonpharmacologic treatment options for long term long term management of gout
Weight loss, exercise, smoking cessation, comorbid conditinos that promote hyperuricemia, increase fluid intake and decrease salt intake
When should maintenance medication be considered for gout
Greater than 2 attacks a year, presence of tophi,CKD stage 2 or worse, urolithiasis (stone formation in the urinary system)
What are the first line medications, HINT: xanthine oxidase inhibitors
Allopurinol and Febuxostat
What are the uricosuric agents (increases uric acid excretion)
Probenecid (first line), Lesinurad, losartan and fenofibrate (off-label)
What is the goal serum uric acid
less than 6 mg/dL (less than 5 mg/dL if trophi)
T/F: Allopurinol is preferred over probenecid if the patient has a CrCl is greater than 50 ml/min and can be used in overproduction and underexcretion
True
What is the dose of allopurinol for osteoarthritis, what if the patient has CKD, drug interactions
100 mg by mouth every day, titrate up by 100 mg per day every 2-5 weeks up to 600-800 mg/day/ start with 50 mg by mouth per day then titrate up by 50 mg per day for a max of 300 mg/day/ azathioprine
What Adverese effect should be monitored if a patient is taking allopurinol
Rash/hypersensitivity
What is the common dose of Febuxostat, what are the risk of using the medication
40 mg daily that can increased to 80 mg per day after two weeks if uric acid is high not/ Not recommended in CrCl less than 30 ml/min, higher risk of CV deaths
What is the dose of probenecid, when should it be used
250 mg BID for 1-2 weeks then 500 mg BID for 2 weeks (increases by 500 mg is advised until max dose of 2 grams is reached)
T/F: Probenecid should not be taken if CrCl is less than 50 ml/min and if someone has had renal stones since
True
What is the MOA of lesinurad, dose, what is BBW
inhibits renal tubular reabsorption of uric acid (URAT transporter), 200 mg/day given at the same time as a XOI (monotherapy could have lower renal function), Avoid in patients with CrCl less than 45ml/min
What recombinant uricase reserved for severe case and is given IV
Pegloticase, 8 mg every every 2 weeks over 2 hours
What medications should be given as prophylaxis when initiating XOI
`Colchine: 0.6 mg BID (every other day if CrCl less than 30)
Naproxen 250 mg BID (others may be used)
Prednisone: Less than 10 mg/day
T/F: Lesinurad can be taken alone
False: Lesinurad must be taken with a XOI
What is the amount of water that should be taken when taking medications
At least 2 hours
