DEAR DR. DONOHUE: Spherocytosis runs in my family. I had my spleen removed at age 6, as did my daughter, now a teenager. Twenty-five years ago, the doctor told me not to use birth-control pills because they would put too much stress on my liver. Is there any medication or substance my daughter should avoid due to her lack of a spleen? How about the Gardasil vaccine? – L.Z.

ANSWER: Spherocytosis is an inherited anemia. Normal red blood cells have a slight indentation in their center. The red blood cells in spherocytosis have no central depression, so they fall to pieces well before they should. Because the spleen is active in removing abnormal red blood cells, taking out the spleen in a person with spherocytosis is often a treatment for the disorder.

The spleen is an integral part of the immune system. It gobbles up germs that have found their way into the circulation. It also makes antibodies to destroy invading germs. People without a spleen are more susceptible to infections. Three bacteria give spleenless people great trouble: pneumococcus (a cause of pneumonia), haemophilus (another cause of pneumonia) and meningococcus (a cause of meningitis).

People missing a spleen should be vaccinated against these germs before the spleen is removed. If that’s impossible, then vaccination should take place after the operation. In fact, all vaccines are recommended for those without a spleen.

Young girls can and should receive the Gardasil vaccine, the vaccine to prevent cancer of the cervix.

I am not aware of any bad effect of birth-control medicine for women without a spleen or any medicine that’s contraindicated for splenectomized people.

Many people, other than those with spherocytosis, have no spleen. Sometimes it’s removed from people who have injured it in an auto accident or from an athlete whose spleen was damaged in contact sports. Not having a spleen puts a person at risk for overwhelming infections, but the risk is not so great that these people cannot live a very active life.

DEAR DR. DONOHUE: I have a 43-year-old daughter who lives more than a thousand miles away from me. She told me her eye doctor diagnosed her with retinitis pigmentosa. She was quite vague about it. What is it? Where did she get it? Is it curable? – P.P.

ANSWER: It’s hard not to be vague about retinitis pigmentosa, because it consists of such a disparate group of conditions. The retina is the backmost part of the eye, where incoming light is transferred into images that are sent to the brain so people can see.

In this condition, clumps of black pigment (the “pigmentosa” part) are scattered in the retina and interfere with sight. This gives rise to visual problems. The first sign of trouble is loss of night vision. Vision off to the side also suffers early on. Blindness is possible, but complete loss of vision doesn’t happen to all.

Vitamin A helps some, and experimental gene therapy is under investigation.

It’s a genetic problem. If the troublesome gene isn’t inherited, the condition is due to a spontaneous gene mutation that takes place during embryonic or fetal life.

You and your daughter can obtain valuable information from the Foundation Fighting Blindness. Its toll-free number is 800-683-5555, and its Web site is www.blindness.org.

DEAR DR. DONOHUE: I woke with swelling and pain in my right knee. The diagnosis is bursitis. I do housekeeping for a living and am on my knees a lot. Will I no longer be able to do this type of work? – T.S.

ANSWER: The body has hundreds of bursa, little discs that allow tendons to pass over bones without generating friction. There’s a bursa near the kneecap. Inflammation of it goes by the common name housemaid’s knee.

Rest and anti-inflammatory drugs like Aleve often can eliminate the pain and swelling. Sometimes a doctor must drain the bursa with a needle and syringe, and then inject cortisone to prevent the fluid from coming back.

You can do your work again. You have to protect your knees with knee pads.

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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