DEAR DR. DONOHUE: My daughter is 32 years old and lives in Europe. Her company sent her there. For quite some time she complained of feeling rundown and had a mysterious itch. She saw many doctors. Finally, one has given her the diagnosis of primary biliary cirrhosis. My husband and I know nothing about this illness, and we would appreciate learning some facts. – K.O.

ANSWER: On hearing the word “cirrhosis,” people have a knee-jerk reflex to conclude that alcohol caused it. Alcohol is only one cause of liver cirrhosis, and primary biliary cirrhosis is an example of a nonalcohol cause.

In cirrhosis, normal liver tissue is replaced with bands of scar tissue. If the scarring is extensive, then the liver can no longer perform all of its assigned functions. The liver makes proteins, blood-clotting factors and bile. Bile is essential for fat digestion. It disposes of some of the waste products generated in the course of a day’s metabolism. It recycles materials that come from the degradation of body cells, such as the hemoglobin part of red blood cells. It has a reserve of stored sugar that it releases into the blood when blood sugar dips.

Primary biliary cirrhosis is an autoimmune disease. Something, as yet unknown, jump-starts the immune system’s production of antibodies that seek out and destroy the tiny liver channels – bile ducts – that drain bile from the liver. Without bile ducts, bile oozes throughout the liver and destroys liver cells. Scar tissue replaces the liver cells.

Your daughter has the two signature symptoms of primary biliary cirrhosis – fatigue and itching.

Ursodeoxycholic acid, a medicine sometimes used for dissolving gallstones, is used in this disorder. Primary biliary cirrhosis patients are some of the best candidates for liver transplantation. I don’t mean to imply that your daughter is destined for a transplant, but it is a solution – if ever it is needed.

DEAR DR. DONOHUE: What is mycoplasma pneumonia? How is it treated? A friend asked me to write you for information. – D.W.

ANSWER: We’re used to thinking that germs are either bacteria or viruses. There are others. Mycoplasmas are an example. In the tree of living organisms, they are a branch between viruses and bacteria. They can cause many kinds of infections. Some are sexually transmitted.

The mycoplasma family you ask about can cause pneumonia, and that is where the disease got the second half of its name. In truth, it causes mild upper respiratory tract infections, similar to colds, more often than it causes pneumonia. Most mild infections resolve themselves without treatment.

The pneumonia coming from mycoplasma is similar to other pneumonias. Cough, fever and headache are the principal symptoms. After the infection is over and done, it can take another month or so for people to feel like themselves again.

Erythromycin, an antibiotic, is often the drug of choice for the pneumonia caused by this organism.

Tell your friend he or she can write to me. I have nothing against him or her.

DEAR DR. DONOHUE: I love sugar and anything sweet. I put so much in my coffee that it amazes bystanders. I have been told that alcoholics love sugar. Does this mean I will become an alcoholic? – D.J.

ANSWER: I once wrote that there was no relationship between sugar craving and alcoholism. I was swamped with letters stating the opposite.

Many of the letter writers were experts in the field of alcohol research and treatment. Some letters were from alcoholics who testified that they most definitely have an attraction to sugar.

Sugar increases the level of serotonin, a brain chemical. Serotonin keeps people from slipping into depression. A significant number of alcoholics use alcohol as a self-treatment for depression. This might be one basis for an alcoholic’s attraction to sugar. Furthermore, some research indicates that the gene reputed to be a cause of alcoholism might also be the gene that draws people to sweets. None of this means you are destined to become an alcoholic.

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.