Q: I hear and read a lot about gout, but I have been diagnosed with pseudogout. What is pseudogout, and how it is treated?

A: Pseudogout often resembles gout and, like gout, is caused by the formation of crystals in the joints, thus the name. But instead of being composed of uric acid, as true gout crystals are, the crystals in pseudogout are composed of a salt called calcium pyrophosophate dihydrate (CPPD). The condition is also called CPPD disease. 

Pseudogout is the most frequent cause of acute arthritis in one joint among older people. Although any joint may be involved, the knee is most commonly affected. A typical attack begins rapidly with severe pain, redness and swelling of the affected joint or joints. The attacks often resolve within a few weeks whether treated or not.

To limit pain and swelling, your doctor may prescribe nonsteroidal anti-inflammatory drugs (NSAIDs) or remove fluid from the infected joint and inject it with a glucocorticoid compound.

Unfortunately, recurrent attacks of pseudogout are not uncommon. Chronic attacks are likely to affect several joints at once, most commonly the wrists, fingers and knees. Like gout, pseudogout primarily involves the body's metabolism (for instance, a problem with iron or calcium metabolism) rather than the immune system. However, there is no specific therapy for the underlying metabolic disorder.

Bernard Rubin, DO, Rheumatologist