Gout: Clinical sciences

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Introduction0:00–0:58

Gout is an acute inflammatory arthritis that occurs when monosodium urate crystals deposit in joints, soft tissue, and bones.
This is typically associated with hyperuricemia due to either underexcretion or overproduction of uric acid. Risk factors include male sex, obesity, drinking too much alcohol, consuming certain foods like red meat and seafood, as well as dehydration, taking diuretics like thiazides, and increased cell turnover like in hemolysis or tumor lysis syndrome.
The diagnosis of gout is made clinically and relies on the presence of classic symptoms, known risk factors, and lab findings.
However, in some cases when the diagnosis is not clear, joint aspiration may be needed. Alright, if a patient presents with signs and symptoms suggestive of gout, you should first perform a focused history and physical examination.

Focused H&P and labs0:58–3:40

As well order labs like a serum urate, CBC, ESR, and CRP. Your patient may report rapid onset of redness, pain, and swelling in a joint, most commonly involving the big toe, but can involve other joints, such as the knee.
This is especially common after drinking alcohol, or consuming purine-rich foods like red meat or seafood. Other risk factors include high fructose intake, diuretic use, obesity, history of diabetes, hypertension, and chronic kidney disease.
Physical exam usually reveals redness, tenderness, and swelling in the involved joints, most often in the first metatarsophalangeal joint.
You may also see subcutaneous nodules, or tophi, on the joints and pads of the digits. As far as labs go, the serum urate will often be elevated, greater than 6.8 milligrams per deciliter, but keep in mind that urate levels can be difficult to interpret during a gout flare.
CBC typically reveals an elevated leukocyte count and inflammatory markers, such as ESR and CRP. If you see this constellation of signs, symptoms, and lab findings, you can diagnose acute gout.
Now lets look at patient with a different but similar focused history and physical results.If your patient reports joint redness, pain, or swelling; but has no obvious risk factors for gout; physical exam reveals redness, tenderness, or swelling, but no tophi present; and if the serum urate, and inflammatory markers are normal Then you should suspect arthritis.
In this case, additional tests are needed to diagnose the type of arthritis. Specifically, perform a joint aspiration of the synovial fluid.
If the synovial fluid contains no negatively birefringent needle-shaped crystals, consider an alternative diagnosis, like pseudogout, septic arthritis, or Lyme arthropathy.
However, if the microscopic synovial fluid shows negatively birefringent needle-shaped crystals with possible yellow cloudy fluid that contains white blood cells, you can diagnose acute gout.
Here’s a high yield fact! Pseudogout is characterized by calcium pyrophosphate crystals, which are rhomboid shaped and positively birefringent crystals, and can help differentiate gout from pseudogout.

Management3:40–4:50

Alright, now that you’ve diagnosed acute gout, let’s turn our attention to management. Within the first 24 hours of symptoms, begin pharmacological management and start your patient on anti-inflammatory medications for at least 7 to 10 days.
Commonly used medications include NSAIDs, like indomethacin or naproxen, but colchicine can also be prescribed. If your patient has impaired renal function or cannot tolerate NSAIDS or colchicine, give an oral or intra-articular glucocorticoid instead.
Keep in mind that you should avoid glucocorticoids if you suspect a concurrent infection or if your patient has brittle diabetes.
You should also review your patient’s medication list, and if they are taking a diuretic, discontinue it or adjust the dose.
Next, counsel your patient on non-pharmacologic treatment options, like resting the affected joint and applying topical ice packs.
Finally, be sure to encourage lifestyle modifications, such as optimizing treatment of comorbid conditions like diabetes and hypertension, maintaining a healthy BMI, as well as minimizing alcohol use and consumption of purine-rich foods.

Assess response4:50–7:55

Ok, now that you’ve treated your patient’s gout flare, let’s switch gears to long term management. Be sure to assess your patient’s response two to four weeks after the acute episode.
Order an X-ray of the affected joint to assess for damage. If your patient has had less than two known gout flares per year, with no visible tophi on physical exam, as well as no joint damage seen on X-Ray, continue lifestyle modifications to prevent future episodes.
On the other hand, if your patient has had two or more gout flares per year with one or more tophi seen on physical exam, as well as x-ray findings indicating joint damage, such as punched out extra-articular erosions or soft tissue gouty tophi, start long-term medical therapy.
Typically, long-term medical therapy involves the introduction of urate-lowering therapy, or ULT for short. However, paradoxically, ULT can initially trigger gout flares.
This is because as soon as ULT is initiated the urate crystals, will start dissolving and get smaller, some may get into another joint before being completely eliminated, causing a flare up.
To prevent this, begin gout-flare prophylaxis. Your patient should take low-dose anti-inflammatories first for 2 to 4 weeks.
Low-dose colchicine is commonly used as first-line prophylaxis, but NSAIDs or glucocorticoids can be used as well. Then, begin urate-lowering therapy with ULTs such as xanthine oxidase inhibitors, like allopurinol or febuxostat.Here’s a clinical pearl to keep in mind!
High serum urate levels not only lead to gout, but can often lead to urate kidney stones. In this case, treat urate nephrolithiasis with the same ULTs, but again, don’t forget prophylactic medications for gout flares.
Ok, so after your patient has been started on ULT, assess the response to treatment in one month. You can do this by checking a serum urate level.
If the serum urate level is under 6 milligrams per deciliter, continue the gout flare prophylaxis for 6 more months, and then stop the anti-inflammatory medication if gout does not recur.
Continue the ULT medication at the current dose, encourage your patient to continue lifestyle modifications and follow your patient’s long-term response to ULT by checking an annual serum urate level.On the flip side, if the serum urate is 6 milligrams per deciliter or more after one month of ULT, you should continue gout flare prophylaxis, while making medication adjustments.
This includes increasing the dose of, or switching to a different xanthine oxidase inhibitor, or adding a uricosuric agent.
Encourage lifestyle modifications, and recheck the serum urate level until you’ve reached a target of less than 6 milligrams per deciliter.
Once your patient’s urate has remained below target for six months, you can discontinue gout flare prophylaxis and continue to follow the serum urate level annually.

Review7:55–10:03

Alright, as a quick recap...If you suspect gout, look for risk factors like alcohol, purine-rich foods, or diuretic use, as well as red, painful, and swollen joints.
You will also see elevated urate levels and inflammatory markers. On the other hand, if the presentation is unclear, perform joint aspiration and synovial fluid analysis.
If there’s negatively birefringent needle-shaped crystals, diagnose gout. Then start NSAIDs or colchicine.
Alternative options include oral and intra-articular glucocorticoids. Additionally, counsel your patient on non-pharmacologic treatment options, like resting, applying ice, and lifestyle modifications.
Reassess in 2 to 4 weeks and order an X-ray. If your patient has less than 2 known episodes of gout per year, no tophi on exam, and no joint damage on X-Ray, continue lifestyle modifications to prevent future episodes.
On the other hand, if your patient has two or more episodes of gout per year, one or more tophi on exam, and joint damage on X-Ray, start prophylactic anti-inflammatory medications for gout flares before you initiate urate-lowering therapy with xanthine oxidase inhibitors.
After starting ULT, reassess in one month by checking a serum urate level. If less than 6 milligrams per deciliter, continue gout flare prophylaxis for 6 more months, and if there’s no recurrence, stop the anti-inflammatory.
Continue the current dose of ULT, lifestyle modifications, and recheck a urate level annually. On the flip side, if after one month of ULT, the serum urate is 6 milligrams per deciliter or greater, continue gout flare prophylaxis, adjust the ULT dose, or switch to a different ULT.
Again, continue lifestyle modifications, and recheck the urate until it’s less than 6 milligrams per deciliter. Once the serum urate level remains below target for six months, discontinue gout flare prophylaxis and continue to follow the