DEAR DRS. DONOHUE AND ROACH: My granddaughter has had diabetes and a fatty liver since she was young. She is 16, overweight and refuses to exercise. She has black rings around her throat. I’ve been told it’s from the diabetes not being properly controlled. Also, I’ve noticed a dark tinge to the skin around her shoulders under the arms. — A.C.G.

ANSWER: It sounds like your granddaughter has acanthosis nigricans, a skin condition strongly associated with diabetes — specifically with type II diabetes, the kind where the problem is resistance to insulin, not a total lack of insulin, as it is in type I diabetes. Type II used to be called “adult onset” or “non-insulin requiring.” However, more frequently, adolescents and even children are being diagnosed with type II diabetes, and some people with type II require insulin. Acanthosis nigricans happens most commonly in the nape of the neck, the underarms and the groin, but in more severe cases, it can include areas around the eyes or around joints. There are other causes, but insulin resistance is by far the most common.

It is important to know that this darkening of the skin (often associated with a thicker, velvet-like texture of the skin) has nothing to do with hygiene, and does not even necessarily relate to diabetes control. It relates to the degree of insulin resistance (the amount of insulin needed to reduce blood sugar is much greater in a person with type II diabetes than in a person without it), and is more common in darker-skinned people.

Being overweight almost always increases insulin resistance, so losing weight usually improves the dark pigmentation. More importantly, weight loss can reduce the fatty liver, reduce the amount of medication needed and make exercise easier. But weight loss can be very, very hard to accomplish, and particularly so for adolescents. I cannot overemphasize the social stigma some adolescent girls feel when they are overweight, and combined with a serious condition like diabetes, it can have a devastating effect on these young women.

A family that is accepting, supportive and encouraging can make all the difference. Helping her choose a better diet and get some exercise — even if it’s inside the house, if she is uncomfortable getting out — likewise can begin to turn around this problem. Working with her doctor and honestly discussing her body-shape issue is important, as many diabetes medicines make losing weight harder — and a few, such as metformin (Glucophage and others) and exenatide (Byetta and others) make weight loss easier.

Finally, for those who are excessively overweight, bariatric surgery has a high cure rate for diabetes. I don’t recommend it often, but we are increasingly considering it in younger diabetics.

DEAR DRS. DONOHUE AND ROACH: I can’t get rid of ringworm. Please help me — I can’t find a doctor to help. — C.S.

ANSWER: Ringworm is a fungal infection of the skin. It has nothing to do with worms. Most of the time, treatment with an over-the-counter antifungal cream, such as miconazole (Desenex and others) or terbinafine (Lamisil and others), twice daily for two or three weeks (until a week or so after the rash fades), usually is effective. If it doesn’t work, it’s time to see a dermatologist.

TO READERS: The booklet on colon cancer provides useful information on the causes and cures of this common malady. Readers can obtain a copy by writing: Dr. Donohue — No. 505, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

Drs. Donohue and Roach regret that they are unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may write the doctors or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers also may order health newsletters from www.rbmamall.com.

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