The Causes of Lupus

The cause(s) of lupus is currently unknown, but there are environmental and genetic factors involved. Some environmental factors which may trigger the disease include infections, antibiotics (especially those in the sulfa and penicillin groups), ultraviolet light, extreme stress, certain drugs, and hormones.

Scientists believe there is a genetic predisposition to the disease, as lupus is known to occur within families. However, there is no known gene or genes which are thought to cause the illness. There are recent discoveries of a gene on chromosome 1 which is associated with lupus in certain families. Previously, genes on chromosome 6 called "immune response genes" were also associated with the disease. Only 10 percent of lupus patients will have a close relative (parent or sibling) who already has or may develop lupus. Statistics show that only about five percent of the children born to individuals with lupus will develop the illness.

Lupus is often called a "woman's disease" despite the fact that many men are affected. Lupus can occur at any age, and in either sex, although it occurs 10-15 times more frequently among adult females than among adult males after puberty or after the emergence into sexual maturity. The symptoms of the disease are the same in men and women. People of African, American Indian, and Asian origin are thought to develop the disease more frequently than Caucasian women. The reasons for this ethnic selection are not clear.

Hormonal factors may explain why lupus occurs more frequently in females than in males. The increase of disease symptoms before menstrual periods and/or during pregnancy support the belief that hormones, particularly estrogen, may somewhat regulate the way the disease progresses. However, the exact reason for the greater prevalence of lupus in women, and the cyclic increase in symptoms, is unknown.