Lupus (Systemic Lupus Erythematosus)

Lupus Overview

Systemic lupus erythematosus (lupus, SLE) is an autoimmune disease in which a person's immune system attacks various organs or cells of the body causing damage and dysfunction. Lupus is called a multisystem disease because it can affect many different tissues and organs in the body. Some patients with lupus have a very mild condition, which can be treated with simple medications, whereas others can have serious, life-threatening complications. Lupus is more common in women than men, and its peak incidence is after puberty-the reason for this is unknown.

While lupus is a chronic illness, it is characterized by periods when the disease activity is minimal or absent (remission) and when it is active (relapse or flare). The outlook for patients with SLE today is much better than years ago because of greater awareness and better tests leading to earlier diagnosis and treatment and more effective and safer medications.

Lupus Causes Genetic link

As with other autoimmune diseases, people with lupus share some type of common genetic link. An identical twin has a 3- to 10-fold greater risk of getting lupus than a nonidentical twin. Also, first-degree relatives (mother, father, brother, sister) of people with lupus have an 8- to 9-fold increased risk of having lupus than the general public.

Environmental factors

Although an identical twin is much more likely to have lupus if her identical sibling has lupus, the likelihood of developing the disease in the unaffected twin is not 100%. Despite the nearly identical genetic makeup of identical twins, the probability of the unaffected twin developing the disease if the other twin has it is around 30-50% or less. This implies that environmental factors may help determine whether or not the disease develops in a person. Outside of random occurrences of lupus, certain drugs, toxins, and diets have been linked in its development. Sun exposure (ultraviolet light) is a known environmental agent that can worsen rashes of lupus patients and sometimes trigger a flare of the entire disease.

Reversible drug-induced lupus

In the past, the drugs most frequently responsible for drug-induced lupus are procainamide (Procanbid), hydralazine (Apresoline), and isoniazid (Laniazid). However, newer medications have been associated with drug-induced lupus, such as the new biological agents used to treat rheumatoid arthritis, etanercept (Enbrel), infliximab (Remicade), adalimumab (Humira). Generally, lupus that is caused by a drug exposure goes away once the drug is stopped.

Association with pregnancy and menstruation

Many women with lupus note that symptoms may be worse after ovulation and better at the beginning of the menstrual period. Estrogen has been implicated in making the condition worse and this problem is currently being studied. For this reason, women with lupus who are on birth control medications are encouraged to take those that contain little or no estrogen.