Types of lupus
There are many different types of lupus, including the following five forms:
1) Systemic lupus erythematosus (SLE)
When most people talk about lupus, they are referring to SLE.
"Systemic" means that the disease can affect numerous parts of the body. The symptoms of SLE can be mild or severe, and although more common in people aged between 15-45, it can additionally occur during childhood or later in life.10
2) Discoid lupus erythematosus (DLE)
DLE is a chronic skin disorder in which a red, raised rash appears on the face, scalp or elsewhere on the body.10
The raised areas may become thick and scaly and may cause scarring. The rash may last for days or years and may recur. Small percentages of people with DLE have or will develop SLE.
3) Subacute cutaneous lupus erythematosus
Subacute cutaneous lupus erythematosus refers to skin lesions that appear on parts of the body exposed to sun. The lesions do not cause scarring.10
4) Drug-induced lupus
There are a number of medications that can cause drug-induced lupus such as some antiseizure, high blood pressure, thyroid medications, antibiotics, antifungals and oral contraceptive pills. The symptoms usually completely disappear once the drug has stopped being taken.10
5) Neonatal lupus
Neonatal lupus is a rare disease that can occur in newborn babies of women with SLE, Sjögren's syndrome, or with no disease at all. Most babies of mothers with SLE are healthy.10
Scientists suspect that neonatal lupus is caused in part by autoantibodies in the mother's blood called anti-Ro (SSA) and anti-La (SSB).
At birth, babies with neonatal lupus have a skin rash, liver problems and low blood counts. These symptoms usually resolve by the time the child is 6 months old, but the most serious manifestation - congenital heart block - requires a pacemaker and has a mortality rate of around 20%.
It is important for women with SLE or other related autoimmune disorders to be under a doctor's care during pregnancy.
The risk of developing lupus is approximately 0.1% in the population, 0.2% in females. Prevalence estimates vary widely and range as high as 1.5 million in the US. A recent study estimated a prevalence in 2005 of 161,000 with definite lupus and 322,000 with definite or probable lupus.2
Risk factors for lupus
Risk factors for developing lupus include:6-8
- Gender - more than 90% of people with lupus are women. Before puberty, boys and girls are equally likely to develop the condition
- Age - symptoms and diagnosis of lupus often occur between the ages of 15-45. Around 15% of people who are later diagnosed with lupus, experienced symptoms before the age of 18
- Race - in the US, lupus is more common, more severe and develops earlier in African-Americans, Hispanics/Latinos, Asian-Americans, Native Americans, Native Hawaiians and Pacific Islanders than in the white population
- Family history - first-degree or second-degree relatives of a person with lupus have a 4-8% risk of developing lupus. One study suggests that sisters of lupus patients have as high as a 10% chance of developing lupus. In another 10-year prospective study, researchers observed a 7% incidence of lupus in first-degree relatives of lupus patients.
Lupus is not contagious, and it cannot be transmitted sexually.
It is uncommon for children under the age of 15 to have lupus. One exception is babies born to women with lupus. These children may have heart, liver or skin problems caused by lupus.11
Although pregnancy in women with lupus is considered high risk, most women with lupus carry their babies safely to the end of their pregnancy. Overall, women with lupus have a higher rate of miscarriage and premature births compared with the general population. In addition, women who have antiphospholipid antibodies are at a greater risk of miscarriage in the second trimester because of their increased risk of blood clotting in the placenta.10
Lupus patients with a history of kidney disease have a higher risk of preeclampsia (hypertension with a build-up of excess watery fluid in cells or tissues of the body). Pregnancy counseling and planning before pregnancy are important. Ideally, a woman should have no signs or symptoms of lupus and be taking no medications for several months before becoming pregnant.
Women diagnosed with lupus may find the results of a new study reassuring, which suggests that most pregnancies among women with the condition have good outcomes if their lupus is inactive. The study also identifies certain risk factors associated with poor outcomes in pregnancies among women with lupus.
On the next page we look at the signs and symptoms of lupus and how lupus is diagnosed and treated.