Overview, Causes, & Risk Factors
Pseudogout is a form of arthritis, or joint inflammation, that is caused by deposits of calcium pyrophosphate crystals in the joints. The crystals cause joint pain and other symptoms. Pseudogout is similar to gout, another form of arthritis in which joint pain is caused by deposits of uric acid crystals.
What is going on in the body?
The joint inflammation of pseudogout is caused by calcium pyrophosphate crystals deposited in the joints. Pseudogout may resemble gout in many ways. The main difference between gout and pseudogout is that the joint crystals are different. In pseudogout, calcium pyrophosphate crystals collect in the joints. In gout, the crystals are uric acid crystals. The crystals in the joint cause similar inflammation and symptoms in both conditions.
What are the causes and risks of the disease?
Pseudogout is caused by the deposit of calcium pyrophosphate crystals in the joints. Why the deposits occur is usually not known. There is some evidence that an enzyme deficiency causes pseudogout, but that cause has not been proven. Occasionally, the cause is hereditary.
Pseudogout is most common in elderly individuals and is more common in males than in females. The risk of pseudogout is increased in individuals who have joint problems from other conditions, such as rheumatoid arthritis. People with hormonal disorders involving the thyroid or parathyroid glands are also more likely to develop pseudogout.
Symptoms & Signs
What are the signs and symptoms of the disease?
Pseudogout commonly affects the knees, and the attacks may last for days or weeks. Pseudogout may also cause joint inflammation in the wrists, ankles, and other joints.
Symptoms of pseudogout include joint pain, joint redness, joint swelling, and chronic arthritis.
Diagnosis & Tests
How is the disease diagnosed?
The diagnosis of gout starts with a medical history and physical examination. Then the healthcare provider may do a joint aspiration, inserting a needle into the joint space to remove some of the joint fluid. The fluid is examined in the laboratory for the presence of calcium pyrophosphate crystals. Joint X-rays might be used to look for crystals in the joint.
Prevention & Expectations
What can be done to prevent the disease?
There is no known prevention for pseudogout. Effective treatment of disorders of the thyroid or parathyroid glands may delay the onset of pseudogout in some individuals.
What are the long-term effects of the disease?
An individual with pseudogout can suffer from worsening arthritis and permanent disability. However, with good treatment, outcomes are usually excellent.
What are the risks to others?
Pseudogout is not contagious and poses no risk to others.
Treatment & Monitoring
What are the treatments for the disease?
Pseudogout is treated with medications to stop inflammation and reduce pain. Colchicine and nonsteroidal anti-inflammatory drugs, or NSAIDs such as ibuprofen or naproxen, are commonly used. Corticosteroids may be given as pills or injected into the affected joint. Sometimes fluid is removed from the joint to help control joint pain and swelling.
What are the side effects of the treatments?
Any time fluid is removed from or injected into a joint, there is a risk of introducing bacteria that can cause infection. Pain and bleeding can also result. Colchicine, nonsteroidal anti-inflammatory drugs, or NSAIDs, and corticosteroids may cause nausea, vomiting, diarrhea, abdominal distress, and allergic reactions.
What happens after treatment for the disease?
Treatment of pseudogout is lifelong, because the disease flares up periodically. Most people can return to regular activity after the acute attacks subside.
How is the disease monitored?
A person with pseudogout should contact a healthcare provider if there is an increase in joint pain or swelling. This may indicate an acute attack that can be treated with medications. Any other new or worsening symptoms also should be reported to the healthcare provider.