Lois Robinson, age 14, of San Antonio, Texas, for her question:

WHAT CAUSES RHEUMATIC FEVER?

Rheumatic fever is a serious disease that often hits children and young adults. Doctors believe that it is caused by a special group of streptococci.

A beta hemolytic streptococci is the name given to the bacteria. These are the same organisms that cause streptococcal sore throat.

No one knows exactly how the streptococci attack the body to cause rheumatic fever.

The disease most often starts with a vague, mild pain in the muscle. Because they are so mild and often occur in children, people have often called them "growing pains." Soon, however, the pains become intense and the person's joints swell.

Sometimes the disease will subside in a few weeks. Sometimes it may continue for months or even years.

Rheumatic fever is one of the greatest causes of heart disease in young persons, although fortunately many may recover fully without heart damage.

Usually at some stage of the disease doctors find that the patient's heart has been affected. In some persons, the involvement may be so minor that it can only be found by using an electrocardiogram. In others, it seriously affects the muscles and valves of the heart.

Often rheumatic fever damages the heart valves so they cannot completely close. Then when the heart pumps blood out into the great body vessels, some of it flows back. Doctors call the sound of this back flowing blood a murmur.

But sometimes the heart valves heal. However, large scars may form that partially shut off the flow of blood between heart chambers. Doctors call this condition stenosis.

Surgery is often used to correct either stenosis or murmur.

Complete bedrest is absolutely neccessary for any person with rheumatic fever, and the rest must continue until all signs of fever and inflammation are gone.

Sometimes in the treatment of rheumatic fever doctors use drugs of the salicylate group, such as aspirin. This is given to help ease the pain. Doctors also sometimes prescribe Cortisone as part of the treatment.

When a patient is finally allowed out of bed, his activities are very gradually increased. It is important that heavy activities are not resumed too quickly.

Because of modern methods of medical treatment, few children develop so much heart damage that normal activity must be curtailed.

Because of proper treatment, most children who have had rheumatic fever are able to attend regular school and enter into all but perhaps the most strenuous activities.

Doctors have found that changes in character of the mucus in body tissue is responsible for many rheumatic diseases. This can include rheumatism, the painful condition that involves the muscles, joints or connective tissues such as tendons and ligaments.