Gout and Pseudogout in the Knee: Sudden Hot, Swollen Knee

What are gout and pseudogout?

Gout happens when uric acid builds up in the blood and forms needle-shaped crystals inside a joint. The body's immune system reacts to the crystals with intense inflammation. The big toe is the classic site, but the knee is one of the most commonly affected large joints.

Pseudogout, now often called calcium pyrophosphate deposition (CPPD) disease, is caused by a different crystal. It tends to affect older adults and the knee is its most common target. The attacks look very similar to gout, which is why the name stuck.

Symptoms in patients' own words

• "I went to bed fine and woke up with my knee red, hot and swollen"
• "Even the bed sheet touching it hurts"
• "I can't bend it or put weight on it"
• "It comes in attacks and settles after a week or so"
• "I feel a bit feverish with it"

Attacks usually build over hours and settle over days to a couple of weeks, even without treatment. Between attacks the knee may feel normal, although repeated attacks can damage the cartilage over time.

Causes and triggers in Qatar

Gout is linked to high uric acid levels, which can run in families and is more common in men, in people carrying extra weight, and in those with high blood pressure, diabetes or kidney disease. Some water tablets (diuretics) raise uric acid.

In Qatar, a few triggers come up often. Dehydration from working or exercising in the summer heat concentrates uric acid. Large meals rich in red meat, organ meats and shellfish, and sugary drinks and juices, can bring on an attack. During Ramadan, long fasting hours with limited fluid followed by a heavy iftar are a recognised trigger, so drinking water steadily between iftar and suhoor helps. If you take gout medicines, plan their timing with your doctor before Ramadan begins.

Pseudogout is more common with age and after knee injury or surgery. It is sometimes linked to thyroid, calcium or iron problems, which simple blood tests can check.

Is it gout or infection?

This is the most important question with a hot, swollen knee. A joint infection (septic arthritis) can destroy cartilage within days and needs urgent treatment. Gout, pseudogout and infection can look identical, and occasionally crystals and infection are present together.

The reliable way to tell them apart is to draw fluid from the knee with a needle (aspiration). The fluid is examined under a special microscope for crystals and sent for tests to look for bacteria. Blood uric acid can be normal during a gout attack, so a normal blood test does not rule gout out, and a high one does not prove it.

Seek urgent care the same day if you have fever or shivers, feel unwell, cannot bear weight, have had a recent knee injection or operation, or have diabetes or a weakened immune system.

Diagnosis

Dr. Gelber examines the knee, asks about past attacks, diet, fluids and medicines, and usually aspirates the joint. Removing the fluid often eases the pain straight away. X-rays can show calcium deposits in the cartilage typical of pseudogout and any wear from repeated attacks. Ultrasound can show crystal deposits and fluid, and blood tests check inflammation, kidney function and uric acid once the attack settles.

Treatment

An acute attack is treated to calm the inflammation quickly. Options include anti-inflammatory medicines, colchicine or a short course of steroid tablets, depending on your kidneys, stomach and other conditions. Once infection is ruled out, a steroid injection into the knee is often very effective. Rest, ice and keeping the leg up help in the first days.

For gout that keeps coming back, long-term medicine to lower uric acid is usually recommended, managed by your family doctor or a rheumatologist. Staying well hydrated, limiting sugary drinks and large meat and seafood meals, and gradual weight loss reduce attacks. There is no medicine that removes pseudogout crystals, so treatment focuses on settling attacks.

Surgery is rarely needed. Arthroscopic washout may be used when infection cannot be excluded or the knee is badly affected, and joint damage from years of attacks is managed like osteoarthritis.

Recovery and when to see a specialist in Doha

With treatment, most attacks improve within days. Return to walking and work as the pain allows, and build back up to sport gradually. See a knee specialist if this is your first hot, swollen knee, if attacks are becoming more frequent, or if the knee does not settle between attacks. Dr. Gelber assesses swollen knees at Aman Hospital in Doha and works with your physician on long-term prevention.