What is the cause of systemic lupus erythematosus

The emergence of systemic lupus erythematosus can cause great harm to the body because immune cells will directly attack normal cells in the body, causing serious damage to organ cells. There are several causes of systemic lupus erythematosus.

The cause of systemic lupus erythematosus is still unclear. Attribution can still be divided into internal and external factors. Internal factors are currently believed to be related to genetic factors, while external factors are related to infection, environment (such as ultraviolet rays), drugs, endocrine, psychological and other factors.

2.1 Genetic factors

The incidence rate in the family of patients with systemic lupus erythematosus can reach 13%, suggesting that it is related to genetics; on the other hand, studies have found that the incidence rate of identical twins is 40%, while the incidence rate of fraternal twins is only 3%; 6 gene loci (1q22-24, 1q41-42, 2q37, 4p15-16, 6p11-22 and 16q12-13) have been found from multiple SLE familial linkage analyses; there are racial and gender differences in the incidence of systemic lupus erythematosus, which also suggests that racial genes and gender genes may be one of the factors; studies at the molecular level have found that the detection rate of susceptibility genes HLA-DR2 and HLA-DR3 in patients with systemic lupus erythematosus is higher than that in normal people.

2.2 Infectious factors

In terms of external factors, inclusion bodies and inclusion-like substances can be found in the glomerular endothelial cells and skin lesions of patients with systemic lupus erythematosus; the titer of antiviral antibodies in the serum is increased; it is currently believed that the onset of systemic lupus erythematosus is related to persistent and slow infection with certain viruses.

2.3 Ultraviolet light

25% to 35% of SLE patients are allergic to sunlight. Studies have shown that ultraviolet radiation can convert skin DNA into thymine dimers, thereby increasing immunogenicity and causing keratinocytes to produce interleukin 1, thereby enhancing the immune response. It is an important environmental factor in stimulating systemic lupus erythematosus.

2.4 Food factors

In terms of food, foods containing psoralen, such as celery, figs, and celery, have the potential to enhance the photosensitivity of patients with systemic lupus erythematosus. Foods containing amine groups, such as mushrooms, certain food fuels (such as tartaric acid foods), smoked foods and tobacco, can induce systemic lupus erythematosus. Foods containing L-concanavalin A, such as alfalfa seeds, sprouts, and various legumes, are also associated with the onset of systemic lupus erythematosus.

2.5 Chemical factors

Some chemicals may also be triggers of SLE, such as hair dyes and lipsticks containing reactive aromatic amines and some organic compounds (such as trichloroethylene, asbestos, silica, etc.) can stimulate systemic lupus erythematosus.

2.6 Drug factors

Drug factors should not be ignored either. Drugs cause systemic lupus erythematosus or lead to disease activity in 3% to 12%. Some antibiotics (such as penicillin, streptomycin, cephalosporin, sulfonamides, etc.), anti-tuberculosis drugs (such as isoniazid), anti-hyperthyroidism drugs, antiarrhythmic drugs, antipsychotics (such as chlorpromazine, phenytoin sodium), phenylbutazone, gold preparations, hydralazine, procainamide and some biological agents (such as certain vaccines, transfer factor, interferon), etc. can cause drug-induced lupus or induce lupus relapse. Studies have found that the expression of HLA-DR4 in patients with drug-induced systemic lupus erythematosus is significantly increased. Some drugs are immunogenic and can stimulate the production of antibodies in the body. In addition, drug-induced systemic lupus erythematosus has a certain dose dependence in addition to the patient's susceptibility. Lupus induced by drugs often has mild clinical manifestations, with less involvement of the kidneys, skin, and nervous system. The onset age is older, the course of the disease is shorter and milder, the complement in the blood is not reduced, more than 90% of antihistamine antibodies are positive, and the blood single-chain DNA antibodies are positive.

2.7 Endocrine factors

Estrogen levels play an important role in the pathogenesis of SLE. The incidence of systemic lupus erythematosus in women of childbearing age is significantly higher than that in men, and the condition worsens in the first three months of pregnancy. The incidence in prepubertal and postmenopausal women is only slightly higher than that in men. Therefore, estrogen is believed to be related to the onset of systemic lupus erythematosus. It has been found that the abnormalities of sex hormones in patients with systemic lupus erythematosus are prominently manifested in that female patients produce stronger and more lasting estrogen effects and weaker androgen effects. Female hormones play an important role in immune regulation.