Gout: an animated, cited guide
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Not medical advice. Gout Companion is an educational synthesis of published literature. It does not replace a clinician.
What is in it
- What gout is Who gets it, the numbers, and the four stages from high urate to tophi.
- Where urate comes from Purines, xanthine oxidase, and how the kidney and gut handle urate.
- Crystals vs serum urate Why crystals form above about 6.8 mg/dL and dissolve below the target.
- A flare, hour by hour From a shed crystal to the NLRP3 inflammasome, interleukin-1β and neutrophils, then resolution.
- Colchicine inside the cell From the pill to the neutrophil to the microtubule.
- Treating a flare Colchicine, NSAIDs, glucocorticoids, IL-1 blockers and ice.
- Colchicine dosing and safety Published doses, kidney function and drug interactions.
- How urate-lowering drugs work Allopurinol, febuxostat, uricosurics and pegloticase.
- Treat to target Titrating to below 6 mg/dL, and why flares rise in the first months.
- Safety of urate-lowering drugs HLA-B*58:01, the CARES and FAST trials, interactions.
- Diagnosis and the ACR/EULAR score Crystals under polarised light, imaging, and the 2015 classification calculator.
- The differential Calcium pyrophosphate crystal arthritis, septic arthritis, cellulitis and others.
- Gout, kidneys and heart Chronic kidney disease, stones, blood pressure and cardiovascular risk.
- Living with gout Diet, alcohol, weight, other medicines and a flare plan.
- Nursing care Assessment, giving the medicines, teaching and documentation.
- Toward a cure Dissolving crystals for good, and the research pipeline.
- History and people From podagra to polarised light and allopurinol.
- Flashcards, quiz and glossary Revision for students.
- Sources Every reference behind the app.
Common questions
What is gout?
Gout is an inflammatory arthritis caused by crystals of monosodium urate that form in and around joints when urate in the blood stays above its solubility limit for long enough. It shows as sudden, very painful flares, most often in the big toe, and the crystals stay between flares unless urate is lowered.
What causes a gout flare?
Immune cells in the joint engulf urate crystals, which switches on the NLRP3 inflammasome and releases interleukin-1 beta. That signal calls in large numbers of neutrophils, which bring the heat, redness, swelling and pain. A flare usually peaks within a day and settles within one to two weeks.
What uric acid level should someone with gout aim for?
Guidelines that use treat-to-target set a serum urate below 6 mg/dL (360 µmol/L) for people on urate-lowering therapy, and EULAR suggests below 5 mg/dL (300 µmol/L) for severe gout with tophi, until the crystals have dissolved.
Why can allopurinol cause flares when you start it?
Lowering urate dissolves and loosens crystal deposits, which can set off flares in the first months. Guidelines advise starting at a low dose, raising it gradually, and taking flare prophylaxis such as low-dose colchicine for three to six months.
How is gout diagnosed?
The reference test is seeing needle-shaped, negatively birefringent urate crystals in joint fluid under polarised light. Without that, the 2015 ACR/EULAR classification criteria score the clinical pattern, serum urate and imaging such as ultrasound or dual-energy CT; 8 or more points classifies as gout.
Is gout linked to kidney and heart disease?
Yes. Gout is common in chronic kidney disease, raises the risk of kidney stones, and travels with high blood pressure and cardiovascular disease; cardiovascular events rise in the weeks after a flare. Whether lowering urate protects the kidney or heart is not established.
Can diet alone control gout?
Diet changes serum urate only modestly. Limiting alcohol, especially beer, sugary drinks and large amounts of meat and seafood helps, but most people with recurrent flares or tophi need urate-lowering medicine to reach the target.
Can gout be cured?
In a sense, yes: keeping serum urate below target for long enough dissolves the crystals, and flares then stop. This usually needs long-term urate-lowering therapy, because urate rises again and crystals re-form if treatment stops.