What's the difference between gout and rheumatoid or other arthritis?

Big differences: Regular arthritis, osteoarthritis, is a mechanical problem involving the wearing away of the cartilage in a joint. It is not a systemic problem. Rheumatoid is an autoimmune disease which is systemic. It tends to affect many joints. Gout involves the formation of a crystal in the joint which causes inflammation. Since each disease has a unique cause, each disease has unique treatments.

Arthritis: Gout is caused by an overproduction of uric acid which is a breakdown product of certain proteins. If the level of uric acid in the blood is too high, gout crystals which under a microscope look like needles will deposit in certain joints like the big toe, elbow or knee and cause severe inflammation and pain. Rheumatoid arthritis/autoimmune condition/the body makes antibodies to the joint lining.