Symptoms vary from person to person, and may come and go. Almost everyone with lupus has joint pain and swelling. Some develop arthritis. Frequently affected joints are the fingers, hands, wrists, and knees. Other common symptoms include:
is a known symptom of lupus, but its relationship to and influence on other aspects of the disease remain to be defined. Causes of photosensitivity may include:
It is typically believed that lupus is influenced by multiple genes. Lupus is usually influenced by gene polymorphisms, 30 of which have now been linked with the disorder. Some of these polymorphisms have been linked very tentatively however, as the role that they play or the degree to which they influence the disease is unknown. Other genes that are commonly thought to be associated with lupus are those in the human leukocyte antigen family. There have been several cases where a single gene influence appears to be present, but this is rare. When a single gene deficiency does cause lupus, it is usually attributed to the complement protein genes C1, C2, or C4. The influence of sex chromosomes and environmental factors are also noteworthy. Usually, these factors contribute to lupus by influencing the immune system. Several studies also indicate a potential association of lupus with mutations in DNA repair genes
Age difference
Lupus can develop in any age, but most commonly in ages 15 to 44, with varying results. Typically, the manifestation of the disease tends to be more acute in those affected who are of younger age. Women are more likely to get it than men. Patients with juvenile-onset lupus are more vulnerable to mucocutaneous manifestations of the disease than any other age group. However, patients with late-onset lupus have a much higher mortality rate. Nearly 50% of those with late-onset lupus die of their affliction. Women who are of childbearing age are also particularly at risk.
Differences in ethnicity
Substantial data have been found to indicate that certain ethnic populations could be more at risk for lupus erythematosus, and have a better or worse prognosis. Asian, African, and Native Americans are more likely to get lupus than Caucasians. Caucasians seem to generally have a more mild manifestation of the disease. Their survival rates after five years were typically around 94–96%, while patients of African and some Asian ethnicities had survival rates closer to 79–92%. The only documented ethnicity that had a higher survival rate than Caucasians were Koreans, who had survival rates nearer to 98%. Among Caucasians, the most common causes of death were complications involving the cardiovascular system, the respiratory system and malignancies. Atherosclerotic cardiovascular disease is more prevalent in African Americans with lupus than in Caucasians with lupus.
Diagnosis
For the diagnosis of lupus, four out of 11 signs must be present. Testing may include:
Antinuclear antibody
CBC with differential
Chest X-ray
Serum creatinine
Urinalysis
Classification
Lupus erythematosus may manifest as systemic disease or in a purely cutaneous form also known as incomplete lupus erythematosus. Lupus has four main types:
Treatment consists primarily of immunosuppressive drugs. A second-line drug is methotrexate in its low-dose schedule. In 2011, the U.S. Food and Drug Administration approved the first new drug for lupus in more than 50 years to be used in the US, belimumab. In addition to medical therapy, cognitive behavioural therapy has also been demonstrated to be effective in reducing stress, anxiety, and depression due to the psychological and social impacts that lupus may have. People with SLE treated with standard care experience a higher risk of opportunistic infections and death than the general population. This risk is higher in men and in African Americans.
Epidemiology
Worldwide
An estimated 5 million people worldwide have some form of lupus disease.
70% of lupus cases diagnosed are systemic lupus erythematosus.
20% of people with lupus will have a parent or sibling who already has lupus or may develop lupus.
about 5% of the children born to individuals with lupus will develop the illness.
United Kingdom
Females in the UK are seven times more likely to be diagnosed with SLE than males.
The estimated number of females in the UK with SLE is 21,700, and the number of males is 3000 — a total of 24,700, or 0.041% of the population.
SLE is more common amongst certain ethnic groups than others, especially those of African origin.
United States
Lupus occurs from infancy to old age, with peak occurrence between ages 15 and 40.
Lupus affects females in the US 6 to 10 times more often than males.
Prevalence data are limited. Estimates vary and range from 1.8 to 7.6 cases per 100,000 persons per year in parts of the continental United States.
In popular culture
In the early seasons of the television show House, members of the eponymous character's medical team often suggested lupus as a diagnosis for their patients, only to be rebuked. The rarity of legitimate lupus diagnoses in the show eventually became a running gag.