DEAR DR. DONOHUE: For half a dozen years, I’ve dealt with psoriasis, and most of the time it is under control. This past year my fingers became stiff and swollen.

I thought it was ordinary arthritis, as I am 55. My doctor says it is psoriatic arthritis. I never knew psoriasis could cause arthritis. The doctor told me it could be quite disabling. I take aspirin for it. Is there anything stronger? — H.H.

ANSWER: Anywhere from 3 percent to 30 percent of people with skin psoriasis come down with a form of arthritis caused by psoriasis. The immune system is responsible for both the skin and joint diseases. The severity of skin psoriasis doesn’t always parallel the development and progress of psoriatic arthritis. Pain and stiffness, as with other forms of arthritis, are present in psoriatic arthritis. The fingers and toes are frequent targets, and they can swell to the point where they have the appearance of sausages. The spine is frequently involved. Almost any joint can be affected. One feature of psoriatic arthritis, not usually seen in any other form of arthritis, is pits in the fingernails.

Disabling arthritis isn’t common in psoriasis. Only about 20 percent are severely incapacitated by it. Some patients experience a remission of all signs for as long as two years, but joint pain and swelling eventually return for most. The stock of medicines for this arthritis is large. Nonsteroidal anti-inflammatory medicines (aspirin, ibuprofen, indomethacin and the many others) are the usual first choices. If they don’t control the illness, the next tier of treatments is called disease modifying antirheumatoid drugs. Methotrexate is an example. It is also useful in controlling skin psoriasis The next tier of drugs is ones that work directly to neutralize body-generated chemicals that inflame and swell joints. Two examples are etanercept (Enbrel) and infliximab (Remicade).

DEAR DR. DONOHUE: All of a sudden, my left hip became painful. The doctor says it’s hip bursitis. Really? I have heard of shoulder and knee bursitis, but I never heard of hip bursitis. Is there really such a thing? — B.W.

ANSWER: Yes, there is such a thing. The body has more than 150 bursas. A bursa is a flat disk placed between tendon and bone so that friction doesn’t develop when the tendon moves across the bone. It’s a ball bearing, but a flat ball bearing. Bursitis — inflammation of a bursa — can occur in any of those 150 disks. Most often, overuse is the cause of bursitis.

Have you started an exercise program? If so, back off a bit. Housemaid’s knee is an example of bursitis. It comes from pressure on the knee bursa. Scrubbing floors or laying carpet irritates the bursa. Rest, moist heat and anti-inflammatory medicines are the standard treatments. If fluid in the bursa is voluminous, doctors can drain it with a needle and syringe. A cortisone injection often brings rapid relief.

DEAR DR. DONOHUE: I am 19 and was just dealt a setback. I have type 1 diabetes, and my doctor calls it brittle diabetes. What makes diabetes brittle? — A.S.

ANSWER: “Brittle” indicates that blood sugar is difficult to control. It swings from highs to lows without an explanation. Now with home monitors for checking blood sugar and with insulin pumps, even brittle diabetes can be managed more readily than it could in the past. The diabetes booklet explains this common condition in depth. To order a copy, write: Dr. Donohue — No. 402, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from www.rbmamall.com.

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