Reports From National Arthritis Meeting
Dr. Shiel Gives Perspectives Of
Interest On Gout & Pseudogout From
Gout has the unique distinction of being one of the most frequently recorded medical illnesses throughout history. It is often related to an inherited abnormality in the body's ability to process uric acid. Uric acid is a breakdown product of purines, which are part of many foods we eat. An abnormality in handling uric acid can cause attacks of painful arthritis (gout attack), kidney stones, and blockage of the kidney tubules with uric acid crystals, leading to kidney failure. On the other hand, some patients may only develop elevated blood uric acid levels (hyperuricemia) without having arthritis or kidney problems. The term "gout" is commonly used to refer to the painful arthritis attacks.
Gouty arthritis is usually an extremely painful attack with a rapid onset of joint inflammation. The joint inflammation is precipitated (brought on) by deposits of uric acid crystals in the joint fluid (synovial fluid) and joint lining (synovial lining). Intense joint inflammation occurs as white blood cells engulf the uric acid crystals and release chemicals of inflammation , thereby causing pain, heat, and redness of the joint tissues.
Pseudogout has many similarities to true gout, which also can cause arthritis. However, the crystal that incites the inflammation of gout is monosodium urate. These two crystals have distinct appearances when joint fluid containing them is viewed under a microscope, making it possible to identify the exact cause of the joint inflammation.
Below are perspectives on key reports presented at the recent national meeting of the American College of Rheumatology.
Dr. Shiel's Perspective: Well, alcohol is old business here. It causes gout by impeding (slowing down) the excretion of uric acid from the kidneys as well as by causing dehydration, which precipitates the crystals in the joints. Animal protein might be something to minimize for gout patients, while calcium-containing foods (such as milk products) may be helpful.
Gout & Pseudogout Combined
Dr. Shiel's Perspective: This means that the two crystal-induced forms of arthritis can coexist. Although this coexistence had been previously reported, this high rate is somewhat surprising. The study was reported from one of the world's experts in the field of crystal arthritis in Philadelphia along with a group from Mexico. The researchers also noted that the cartilage of patients who had both forms of crystals in their joint fluid was often visibly calcified, as seen on x-ray images.
Intravenous Colchicine Dangers
Dr. Shiel's Perspective: Colchicine is commonly used to treat both gout and pseudogout. Typically, it is given by mouth in these instances. However, occasionally there is no other method of administration in certain patients except to give it by vein (intravenously). This study strongly emphasizes that when it used in this manner, colchicine can be dangerous if the doses exceed the maximum recommended cumulative dose of treatment of 4 milligrams. Also, the doses must be reduced in patients with kidney or liver dysfunction and in the elderly.
Dr. Shiel's Perspective: This information will help doctors choose which drug to offer for the treatment of chronic gout. The options are allopurinol (which prevents the body from making uric acid) and drugs such as benemid (which flushes uric acid out of the body through the kidneys). If a patient has an acid urine, it may be best to choose allopurinol to avoid precipitating (causing) kidney stone formation.
Age, high body weight, and water pill usage (diuretics) were each reported to be risk factors for gout.
Dr. Shiel's Perspective: This is not really very new information, but encourages doctors and patients to emphasize weight control and to minimize the use of water pills to avoid gout attacks. (It is a policy that I have used for decades in my practice.)
Last Editorial Review: 12/30/2004