DEAR DR. DONOHUE: Recently my niece was diagnosed with E. coli. I want to know more about that disease. How do you contract it? Is it contagious? How is it treated? Does it affect certain parts of the body? Is it painful? Can it be cured? Is it fatal? — M.W.

ANSWER: E. coli isn’t an illness. It’s a germ, a bacterium. We share planet Earth with it. The E. coli germ has a number of different strains. Some live at peace with us in our colon. If they escape from the colon and invade other body sites, like the circulation, they cause problems. Other E. coli germs are found in soil, water and the digestive tracts of many animals.

Infections with E. coli often occur through drinking water contaminated with it or by eating foods covered with it. In a small number of instances, it is spread via person-to-person contact. Or, as I mentioned, it might escape its home in the colon and cause serious blood infections. E. coli is the No. 1 cause of urinary tract infections. It often ascends into the bladder through the urethra, the tube that empties the bladder to the outside world.

The treatment for an E. coli infection is antibiotics. It can be cured. It also can be fatal; a blood infection with E. coli, for example, can be deadly. So can an infection of the brain coverings, the meninges. Such an infection is meningitis. Infants are the greatest targets of E. coli meningitis.

Symptoms depend on where the E. coli infection is. Infections of the digestive tract lead to nausea, vomiting and diarrhea. Infections of the urinary tract cause painful and frequent urination. Infections of the brain coverings bring listlessness, irritability, coma and death if not treated. Pain is involved with most E. coli infections.

DEAR DR. DONOHUE: Recently I heard that too much zinc in your system causes nerve damage.

I have taken a multivitamin and a calcium-magnesium-zinc tablet daily for years. I am taking a total of 40 mg of zinc each day. Is that a safe amount? — S.P.

ANSWER: The upper daily limit established for zinc is 40 milligrams. The recommended daily intake for adult men is 11 mg and for adult women, 8 mg.

Zinc has many functions. It’s involved with more than 100 enzymes in daily cell chemistry. It affects growth. It encourages wound healing and cell repair. It’s involved with the synthesis of DNA, the stuff that is control central for body cells.

Too much zinc lowers copper levels and leads to an anemia. Amounts greater than 300 mg a day impair the immune system.

I have looked and looked but can’t find any information that excessive amounts damage nerves.

DEAR DR. DONOHUE: I had my spleen removed about 50 years ago. They really didn’t know that much about it then or how best to remove it. They had to get a special doctor to do the operation.

What I would like to know is if, without a spleen, you feel the cold more than other people do. — K.B.

ANSWER: The spleen is in the upper left side of the abdomen in close proximity to the stomach. It’s about 5 inches long and 3 inches wide. It weighs 5 ounces. The spleen serves as a storage site for blood. It cleans the blood, removing worn-out red blood cells and siphoning off germs. It’s an integral part of the immune system, producing antibodies to bombard viruses and bacteria. Without a spleen, a person is more susceptible to infections. For that reason, people without one must keep their immunization shots up to date. That’s particularly important for the pneumococcus vaccine, the pneumonia shot.

Not having a spleen doesn’t make a person feel cold.

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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