Discoid lupus erythematosus

Introduction to discoid lupus erythematosus Discoid lupus erythematosus (DLE) is a chronic recurrent disease that primarily invades the skin and is characterized by well-defined red patches (erythema), hair follicle embolism, scales, telangiectasia, and skin atrophy. The cause is unclear. More common in women, the highest incidence rate around 30 years old. The disease can be divided into two types: 1 limited skin damage is limited to the skin above the neck; 2 disseminated skin lesions affect the skin of a wide range of parts of the body. Some authors believe that the disseminated type is easily converted to systemic lupus erythematosus. basic knowledge The proportion of illness: 0.001% Susceptible people: no specific population Mode of infection: non-infectious Complications: squamous cell carcinoma

Cause of discoid lupus erythematosus

Genetic factors (25%):

The prevalence of this disease varies among races. Different strains of mice (NEB/NEWF, MRL1/1pr) spontaneously develop SLE symptoms after several months of birth. Family surveys show that first- and second-degree relatives of SLE patients About 10% to 20% may have the same kind of disease, some have hyperglobulinemia, a variety of autoantibodies and T inhibit cell dysfunction.

Drug factors (20%):

It has been reported that in 1193 cases of SLE, the incidence of drug-related patients accounted for 3% to 12%. The difference between drug-induced wolverine-like syndrome and idiopathic lupus erythematosus is: 1 clinical Qinghai, involving the kidney, skin and nervous system Less; 2 the age of onset is larger; 3 the course of disease is shorter and lighter; 4 the complement of blood does not decrease; 5 serum single-stranded DNA antibody is positive.

Infection factor (15%):

Some people think that the pathogenesis of SLE is related to the infection of certain viruses (especially lentivirus). From the patients with glomerular endothelial cytoplasm, vascular endothelial cells, and lesions, substances similar to inclusion bodies can be found, and the serum of patients is increased. Especially for measles virus, parainfluenza virus type III, EB virus, rubella virus and viscovirus.

Physical factors (10%):

Ultraviolet light can induce skin lesions or aggravate the original lesions. In a few cases, systemic lesions can be induced or aggravated. About 1/3 of SLE patients are allergic to sunlight.

Pathogenesis

The cause of this disease is unknown. Recent studies have confirmed that this disease is characterized by various immune response abnormalities. As for the factors that cause immune disorders, it may be multifaceted.

(1) Genetic background

The prevalence of this disease is consistent with a single-oval twin incidence of 24% to 57%, while double-oval twins are 3% to 9%. HLA typing shows that SLE patients are associated with HLA-B8, -DR2, -DR3, Some patients can be associated with complement C2, C4 deficiency, and even TNFa polymorphism; the lack of homozygous C2 gene, and the high frequency of -DQ are closely related to DSLE; T cell receptor (TCR) is easy to SLE Sensibility is also related. The low level of TNFa may be the genetic basis of lupus nephritis. All of the above suggests that SL has a genetic predisposition. According to Huashan Hospital's investigation of 100 SLE family members, it is multi-gene inherited, and environmental factors are also lifting. effect.

(two) drugs

It has been reported that in 1193 cases of SLE, the incidence of drug-related patients accounted for 3% to 12%, drug-induced disease can be divided into two categories, the first category is drugs that induce SLE symptoms such as penicillin, sulfonamides, Baotaisong, gold preparations, etc. These drugs enter the body, first cause allergic reactions, and then stimulate the quality of lupus or potential SLE patients with idiopathic SLE, or exacerbate the condition of SLE already suffering, usually stopping the drug can not prevent the disease from developing, the second is to cause lupus Drugs of the syndrome, such as hydrazine hydrochloride (hydralazine), procainamide, chlorpromazine, phenytoin sodium, isoniazid, etc., these drugs are used for a longer period of time and larger doses Afterwards, patients may have clinical signs and laboratory changes in SLE, and their pathogenesis is not clear: for example, chlorpromazine is thought to be slowly combined with double-stranded NDA, and UVA irradiation is rapidly combined with denatured DNA, and clinically exposed to the skin. After daylight, the double-stranded DNA can be denatured and easily combined with chlorpromazine to produce an antigenic substance; and if hydralazine binds to soluble nucleoprotein, it can enhance the immunogenicity of its own tissue components in the body. Syndrome in Symptoms can subside autogenous drug or a small number of residual symptoms subside, HLA typing DR4 shown positive rate was significantly higher, are known as drug-induced SLE genetic quality.

(three) infection

There are dsRNA, ds-DNA and RNA-DNA antibodies in the serum of the patient. The former can only be found in tissues with viral infection. Under the electron microscope, these inclusion bodies are in a small tube network structure with a diameter of 20-25 m. Cluster distribution, but can also be seen in dermatomyositis, scleroderma, acute sclerosing encephalitis. It has not been successful to isolate the virus from tissues with inclusion body-like substances, so these substances and viral joints have yet to be confirmed. It has been suggested that the pathogenesis of SLE is closely related to C-type RNA virus. The authors have an increase of 72.3% in serum Syphilin in 47 cases of SLE, which is -type, containing acid stability and acid instability. Interferon concentration and disease activity Parallel, alpha-type interferon is known to be produced by stimulation of viruses, polynucleotides or bacterial lipopolysaccharides, which indirectly suggests the possibility of viral infection. It is also believed that the onset of LE is associated with tuberculosis or streptococcal infection.

(4) Physical factors

Epstein UV-irradiated skin type LE patients, about half of the cases of clinical and histological typical skin lesions, two months after the skin fluorescent band test positive, such as pre-administration of A can prevent skin lesions, normal human skin double-stranded DNA is not It is immunogenic, and after dimerization by ultraviolet irradiation, the thymine dimer of DNA depolymerization is converted into a strong immunogenic molecule. LE patients have confirmed defects in repairing dimerized DNA, and some people think that ultraviolet rays are also known. First, the skin cells are damaged, anti-nuclear factors can enter the cells, and the nucleus acts to produce skin damage. Cold, strong electro-optic irradiation can also induce or aggravate the disease. Some localized discoid lupus erythematosus can evolve into Systematic, from chronic to acute.

(5) Endocrine factors

In view of the fact that women with this disease are significantly more than men, and more often in the growth period, it is believed that estrogen is related to the occurrence of this disease. By castration, the condition of female NZB mice is relieved, and the male rats are intensified to support the role of estrogen. Significant reduction in the disease during gonad-free activity, ie under 15 years of age and after 50 years of age, in addition to oral contraceptives can induce lupus-like syndrome, there are authors of 20 male SLE determination of sex hormone levels found in 50% of patients with serum estradiol The level increased (5% in the control group), the testosterone decreased in 65% of patients (10% in the control group), and the estradiol/testosterone ratio was higher than that in the healthy control group. All of the above images support the theory of estrogen, and the condition of SLE during pregnancy. The change is also related to the increase of sex hormone levels. Since the progesterone level is rapidly increased, the progesterone/estradiol ratio is correspondingly increased, so that the condition is relatively stable and the progesterone level is lowered after birth. Therefore, the virus may be aggravated again, and the serum of SLE patients is recently found. A higher prolactin value, leading to secondary changes in sex hormones, is for further study.

(6) Immune abnormalities

A person with LE genetic quality, under the above-mentioned various incentives, makes the body's immune stability disorder disorder. When the genetic factors are strong, weak external stimuli can cause disease. On the contrary, when the genetic factors are weak, the disease Strong external stimuli are required, and the immune stability disorder of the body leads to the regulation of the immune system, and the inhibition of T cell loss, not only in quantity but also in function, makes it impossible to regulate B lymphocytes with potential to produce autoantibodies. A large number of autoantibodies are formed to cause disease. Some people have found excessive B cell hyperactivity in lupus mice, but no defects in regulating T cells have been observed. B lymphocyte strains producing autoantibodies have been proposed to escape the control and regulation of T cells. That is, when the T lymphocyte regulation function is normal, it can also produce autoantibodies, which is the so-called B cell escape theory of SLE. Some people think that because the function of helper T cells is too strong, it causes a large number of autoantibodies due to immunoregulatory disorders. It has been suggested that there may be hyperactivity of monocytes or macrophages, usually producing a certain factor that stimulates helper T. Cells, or directly stimulate B cells, causing autoimmunity, the person who proposed "forbidden plant theory" thinks that the body's immune stability disorder, leading to the imbalance of T, B cell ratio or B helper / induced cell and T inhibition / cytotoxic cell imbalance, As a result, the cells of the banned plant were out of control, and excessive proliferation caused autoimmune diseases.

Recent studies have found that SLE patients have abnormal cytokine secretion, IL-1 is synthesized by mononuclear macrophages, which can proliferate B cells of SLE, mediate B cells spontaneously produce IgG, form immune complexes, cause tissue damage, MRL/1pr mouse kidney macrophages contain more IL-1 mRNA, which can produce a large amount of IL-1 in vitro. IL-1 can induce the production of IL-6, IL-8, TNF and other inflammatory factors, which is related to the occurrence of lupus nephritis. IL-1 activity is related to light sensitivity. About 50% of patients have elevated serum IL-2 levels. Almost all SLE patients have high levels of IL-2R in serum, and the active period is higher than the remission period. IL-2 is mainly composed of CD+4T. Cell production; growth factor for T cells, in addition to elevated serum IL-6 levels in SLE patients, more obvious in active phase, in the SLE patients with central nervous system SEL active period, IL-10 levels increased, IgG production increased, more Evidence suggests that IL-10 plays an important role in the abnormal activation of B cells. These cytokine network dynamic imbalances cause abnormal immune responses and also participate in local pathogenic effects.

The mechanism of self-antigen formation can be due to

1 After the action of drugs, viruses or bacteria, ultraviolet rays, etc., the components are modified to obtain antigenicity.

2 The release of hidden antigens, such as thyroglobulin, crystals, sperm, etc., is isolated from the bloodstream and lymphatic system. After the trauma or infection, the barrier is destroyed. These tissue components enter the bloodstream and come into contact with the immune cells. Antigenic substance.

3 cross-allergy results.

pathology

Due to the different types of skin lesions taken by biopsy specimens, the pathological changes are also different. The following pathological changes can be used as a basis for diagnosis:

1 hyperkeratosis accompanied by horny plugs.

2 acanthosis atrophy.

3 The basal layer is liquefied.

4 There is a patchy infiltration of lymphocytes around the skin appendage.

5 upper edema of the dermis, vasodilation and mild red blood cell extravasation.

The change of dermis precedes the epidermis, and the focal liquefaction and degeneration of the basal layer is the main basis for the histological diagnosis of this disease.

Pathological mechanism of Chinese medicine

Chinese medicine believes that the scope of the disease can be related to traditional Chinese medicine, such as chronic diseases, internal injuries and skin diseases, and its pathogenesis can be summarized into internal and external factors.

(1) Internal Cause: Insufficient endowment of kidney: loss of kidney essence, or internal injury of seven emotions, fatigue and imbalance of yin and yang, loss of blood and blood, and poor blood supply, qi stagnation and blood stasis, which is the internal basis for the formation of this disease.

(2) External causes: feeling the external evils: the external invasion of heat and poison is the external condition that causes the disease to occur.

According to the theory that "kid is the congenital", "women take the liver as congenital" and the five internal organs breed each other, liver and kidney deficiency often lead to viscera, qi, yin and yang deficiency. After feeling the foreign sinister poison, on the one hand, it can damage the skin. On the other hand, it can erode the erythema and muscle and joint lesions; on the other hand, it can attack the internal organs and internal organs, affecting the function of the organs, and the micro-transportation of the water valley is abnormal, mainly manifested by the loss of Yin liquid at the beginning of the disease, and the internal heat of the Yin deficiency gradually develops to the lesion. Heyang, yin and yang deficiency, can eventually endanger life due to yang deficiency and even yin and yang. The acute phase of this disease is mostly caused by evil heat and skin stagnation. In the chronic phase or remission period, it is mostly evil. Virtual, the skin is mainly visceral stasis.

Discoid lupus erythematosus prevention

Remove all causes, including a variety of possible internal medicines, chronic infections, etc., to avoid irritating topical drugs and all external stimuli. Avoid exposure to sunlight and ultraviolet light.

Discoid lupus erythematosus Complications squamous cell carcinoma

A common complication of this disease is cutaneous squamous cell carcinoma.

Symptoms of discoid lupus erythematosus common symptoms discoid erythematous papules pruritus nodules scaly esophageal peristalsis poor expansion... edema lipitis

Most of the patients are women, aged 20 to 40 years old, and the skin lesions occur on the face, especially the cheeks and bridge of the nose. They are butterfly-shaped, followed by the lips, ears, scalp, back of the hands and fingers. The characteristic of the lesion is persistent discoid erythema with clear edges, slightly bulging, deep pigmentation, size from soybean to nail, round disc shape or irregularity, surface telangiectasia, and adhesive scales. If the scales are peeled off, the dilated hair follicle holes can be seen. The scaly bottom has many thorny horny ridges, which are tied in the hair follicle mouth. During the development of the disease, the lesions gradually expand and increase, and can be fused into the nose bridge as the center. The butterfly-shaped erythema of the bird, the auricle of the outer ear, the sputum and even the scalp can be affected. When the lesion occurs in the auricle, the soft tissue can be affected, with a wilting shape. When the scalp is involved, the scalp shrinks and the hair falls off. It is dark red and light red. Or with white patches, the back of the hand, the fingers and the back of the foot can be affected at the same time. Individual cases, face, hands and fingers can be all involved, bright red, covered with thin sputum, and the tip of the finger can grow the claw-like horny Hyperplasia, foot lesions are mainly found on both sides of the sole and heel, covered with large patches of reddish scales. In a few cases, the skin lesions involve the lips and oral mucosa, showing grayish white keratosis, which can form erosion and shallow ulcers. Shrinking, can have varying degrees of itching and burning.

There are three variants of this disease: simple erythematous lesions are red spots or papules, local mild desquamation and slight edema; hypertrophic lesions are composed of inflamed and hyperkeratotic skin of the ridge, which is generally located on the face. And the upper extremity stretched, easily misdiagnosed as hypertrophic psoriasis or hypertrophic lichen planus; deep skin lesions are a rare skin lesion, manifested as deep nodules in the skin, often accompanied by discoid lesions, subcutaneous fat Lipiditis can occur, leaving deep local depressions in the lesion area.

Examination of discoid lupus erythematosus

First, check the performance of oral and maxillofacial should pay attention to:

1. Check the red part of the lips for erythema, scales, atrophy, erosion, fading or pigmentation, and whether the lesions extend to the skin.

2. There is no erythema in the mucosa of the mouth, erosive, atrophy, and there are white short lines arranged in a radial arrangement.

3. Check the cheeks for butterfly-like erythema, scales, horny plugs, hypopigmentation or atrophy.

Second, the experimental examination of this disease is less positive, about 1/3 of cases may have mild anemia, leukopenia, thrombocytopenia, and increased erythrocyte sedimentation rate.

IgG is elevated or positive for antinuclear antibodies, and LE cases are positive in some cases, with liver dysfunction.

Diagnosis and diagnosis of discoid lupus erythematosus

The diagnosis is based on the presence of bright red or reddish plaques on the face of women aged 20 to 40 years. The edges are clear and more or less butterfly-shaped. They are covered with adhesive scales and enlarged pores. The diagnosis is generally not difficult. Pathological examination helps to confirm the diagnosis.

Differential diagnosis

1. Chronic pleomorphic sun rash: patchy pleomorphic sun rash is similar to this disease. In the early stage, it is difficult to distinguish between clinical and pathological, but with a certain dose of ultraviolet radiation, it can induce multiple patchy The normal skin of a patient with sun rash has a sun rash, and the normal skin of a lupus patient cannot induce skin lesions, thereby identifying the two.

In addition, the skin lesions of chronic polymorphic sun rash are exposed to sunlight, and the skin lesions have no sticky scales and atrophy.

2. Seborrheic dermatitis and psoriasis Seborrheic dermatitis or early psoriasis: may be butterfly-shaped, distributed on the face of the bridge of the nose, can be confused with discoid lupus erythematosus, but the histological changes of lesion biopsy Significantly different, in addition, seborrheic dermatitis generally responds well to topical treatment, and the disease does not respond well to topical treatment.

3. Basal cell epithelial tumor: superficial basal cell epithelioma can be similar to the isolated lesion of the disease, but the edge of the lesion is progressively dilated, the capillaries around the lesion are dilated, the center is covered with scales, and atrophy can occur. Although the lesion is similar to the static lesion of the disease, the pathological changes of the two are completely different.

4. Skin lymphocytic infiltration: mainly involving the face, clinically easy to be confused with early chronic discoid lupus erythematosus, the lesion is disc-shaped, slightly uplifted, reddish, beginning to appear as small patches, gradually expanding to the periphery, center No scales, no hyperkeratosis of hair follicles, self-resolving without scar formation, histopathological changes of lesions mainly in the dermis, mild swelling of the epidermis, intact epidermal-skin junction, and dense lymphoid lymph nodes Infiltrating cells, infiltrating cells are small lymphocytes, often located around blood vessels and appendages, because skin lymphocyte infiltration is effective against malaria drugs and glucocorticoids, so some authors believe that it is a special type of this disease.

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