Pseudogout (SOO-doe-gout) is a form of arthritis characterized by sudden, painful swelling in one or more of your joints. These episodes can last for days or weeks. The most commonly affected joint is the knee.
Also called calcium pyrophosphate deposition disease or CPPD, the common term "pseudogout" was coined for the condition's similarity to gout. Crystal deposits within a joint cause both conditions, although the type of crystal differs for each condition.
It isn't clear why crystals form in your joints and cause pseudogout, but the risk increases with age. Treatments can help relieve pain and reduce inflammation.
Pseudogout most commonly affects the knees. Less often, wrists and ankles are involved. In many cases, there are no symptoms. However, during a pseudogout attack, the affected joints are usually:
Make an appointment with your doctor if you have sudden, intense joint pain and swelling.
Pseudogout has been linked to the presence of calcium pyrophosphate dihydrate crystals within the affected joint. These crystals become more numerous as people age, appearing in nearly half the population older than age 85. But most people who have these crystal deposits never develop pseudogout. It's not clear why some people have symptoms and others don't.
Factors that can increase your risk of pseudogout include:
The crystal deposits associated with pseudogout can also cause joint damage, which can mimic the signs and symptoms of osteoarthritis or rheumatoid arthritis.
Pseudogout signs and symptoms can mimic those of gout and other types of arthritis, so lab and imaging tests are usually necessary to confirm a diagnosis.
Blood tests can check for problems with your thyroid and parathyroid glands, as well as for a variety of mineral imbalances that have been linked to pseudogout. Your doctor may withdraw a sample of the fluid from your affected joint with a needle to test for the presence of crystals.
X-rays of your affected joint often can reveal joint damage and crystal deposits in the joint's cartilage.
There's no cure for pseudogout, but a combination of treatments can help relieve pain and improve the joint's function.
If over-the-counter pain relievers aren't enough, your doctor may suggest:
To relieve pain and pressure in an affected joint, your doctor inserts a needle and removes some of the joint fluid, which helps remove some of the crystals from the joint. The doctor will then inject the joint with a numbing medication and a corticosteroid to decrease inflammation.
Home treatments may be useful during pseudogout flare-ups. Examples include:
You'll probably first see your family doctor. After an initial examination, your doctor may refer you to a specialist in the diagnosis and treatment of arthritis and other inflammatory joint conditions (rheumatologist).
Here's some information to help you get ready for your appointment.
Before your appointment, you may want to write a list of answers to the following questions:
A doctor who sees you for symptoms common to pseudogout may ask a number of questions, such as:
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