autosensitivity dermatitis
Introduction
Introduction to self-sensitive dermatitis Self-sensitive dermatitis is an acute skin inflammation caused by an allergic reaction to certain substances produced by the patient's internal or skin lesions. Before the onset of the disease, there are often primary lesions such as contact dermatitis, hoarding dermatitis, coin-shaped eczema, and severe athlete's foot in some parts of the patient's skin. It has also been reported to occur after radiation therapy. Due to improper treatment or deterioration of the primary disease due to physical or chemical stimulation, bacterial infection, etc., combined with improper treatment, the wound surface is unclean, so that tissue decomposition products, bacterial products, etc. form a special autoantigen, which is absorbed and systemic allergy occurs. Causes a rash around the body and the body. Self-sensitive dermatitis usually occurs several days to several weeks after the initial skin lesions are aggravated. Skin lesions have a tendency to be symmetrically distributed. Except for new skin lesions near the primary lesion, the symmetry distribution is diffuse or scattered in papules, herpes, and blisters. It is clustered and can be fused and the boundary is unclear. It can be seen that "the same shape phenomenon", such as a rash arranged in a line along the scratching site. A small number of patients can develop eczema erythroderma. The rash is most common in the limbs and can also be seen on the face, less involved in the trunk. basic knowledge Sickness ratio: 0.05% Susceptible people: no specific population Mode of infection: non-infectious Complications: pruritus
Cause
Cause of self-sensitive dermatitis
Infection (35%):
Such as the blood-borne dissemination of allergens such as bacteria and its exotoxins and fungi, similar to the blood-borne dissemination of microbial products, resulting in a variety of skin non-infective manifestations in the distant parts of the infection, such as "tuberculosis", " Bacterial rash, "sputum rash".
Skin inflammation (40%):
The inflammatory process of the skin, whether it is allergic, irritating or infectious, can reduce the stimulation threshold of the skin at the distant site, activate the memory T cells in the circulation, and promote the production of proinflammatory mediator IL-1, IL-6 by keratinocytes. TNF- and the like mediate the inflammatory reaction, thereby causing the occurrence of eczema reaction.
Response to epidermal antigens (20%):
The skin reacts differently to the surface and can cause the disease.
Prevention
Self-sensitive dermatitis prevention
(1) As far as possible to find the cause of the patient's onset or induced aggravation, and actively treat the primary lesion.
(2) Avoid local external bad stimuli as much as possible, such as hot water washing, intense scratching and irritating topical drugs, etc., to avoid hot foods such as seafood, peppers, and wine.
(3) Keep the skin clean and prevent skin infections.
(4) Avoid wearing chemical fiber and woolen clothing directly in contact with the skin.
Complication
Self-sensitive dermatitis complications Complications pruritus
There may be papules, blisters, and pruritus.
Symptom
Self-sensitive dermatitis symptoms Common symptoms Itching skin maculopapular papules erosive blister skin itching scratches skin itching
Self-sensitive dermatitis usually occurs several days to several weeks after the initial skin lesions are aggravated. Skin lesions have a tendency to be symmetrically distributed. Except for new skin lesions near the primary lesion, the symmetry distribution is diffuse or scattered in papules, herpes, and blisters. It is clustered and can be fused and the boundary is unclear. It can be seen that "the same shape phenomenon", such as a rash arranged in a line along the scratching site. A small number of patients can develop eczema erythroderma. The rash is most common in the limbs and can also be seen on the face, less involved in the trunk. Consciously itching is intense.
Examine
Self-sensitive dermatitis examination
Before the onset of the disease, there are often primary lesions such as eczema on the skin. Due to improper treatment or secondary infection, local damage suddenly aggravates, and generalized facial or distant rash and herpes, blister, and other features should be considered. Self-sensitive dermatitis, ulcers, sinus, chronic suppurative otitis media and other medical history should consider infectious eczema-like dermatitis. Can be diagnosed by allergic time.
Diagnosis
Diagnosis and differentiation of self-sensitive dermatitis
Different from other types of dermatitis, such as sun dermatitis, atopic dermatitis, exfoliative dermatitis.
Solar dermatitis is caused by phototoxic or photoallergic reactions after exposure to sunlight. Solar dermatitis, also known as sun rash, medical research believes that the sudden increase of ultraviolet rays in the sun will damage the epidermal cells of the skin, causing degeneration and decomposition of proteins, telangiectasia and congestion, leading to dermatitis.
Allergic dermatitis is a skin disease caused by allergens. It mainly refers to skin diseases such as redness, itching, wheal, peeling, etc. caused by exposure to certain allergens. Specific allergens can be divided into four categories: contact allergens, inhaled allergens, ingested allergens, and injected into allergens.
Exfoliative dermatitis is a rare and serious skin disease. Also known as erythroderma. It is characterized by diffuse erythema, swelling and scaling of the whole body or large areas of the skin.
