Q: I am a 50-year-old man recently diagnosed with rheumatoid arthritis (RA). But I have had joint symptoms for some time, beginning two years ago with a bout of excruciating pain and swelling in my left toe and progressing to episodes of pain and swelling in my feet, knees and wrists. While these incidents may have been early signs of rheumatoid arthritis, gout is also a concern of mine. Do you think I have arthritis or gout?

A: It sounds to me like you have gouty arthritis, or gout, an inflammatory disease that occurs when excess uric acid (a bodily waste product) circulating in the bloodstream is deposited as sodium urate crystals in certain joints. 

The excess uric acid may be caused by genetic factors or kidney disease. The condition may be aggravated by certain drugs such as diuretics and low doses of aspirin or by consuming too much alcohol or foods rich in purines, which are broken down into uric acid.

If your physician didn't know about your previous problems, it's not surprising he diagnosed your condition as rheumatoid arthritis; gout was probably not even on the radar. In its later stages gout can look a lot like RA, causing pain and inflammation in multiple joints. 

In some cases, untreated gout can be associated with a positive rheumatoid factor, an antibody often detected in the blood of people with rheumatoid arthritis. Even buildups of sodium urate can form lumps under the skin that resemble the nodules fairly common in RA.

But that's where the similarity ends. The causes and treatments are entirely different. Unlike gouty arthritis, RA occurs when the body’s immune system – which normally protects us from infection – mistakenly attacks the thin membrane that lines the joints. RA may begin acutely in many joints or start gradually in several joints causing damage and pain. Initially, the involved joints are the knuckles, middle joints of the fingers, wrists, and joints that attach the toes to the feet.

Gout, on the other hand, often starts as your problem did – with excruciating pain and swelling in the big toe – and often follows a trauma such as an illness or injury. Subsequent attacks may occur off and on in other joints – primarily those of the foot and knee – before becoming chronic. In its chronic stage, gout can affect many joints, including those of the hands. But this can take a few years to happen.