physical skin disease
Introduction
Introduction to physical skin diseases Physical skin disease refers to an adverse reaction caused by various physical factors (mechanical friction, temperature, humidity, light, electromagnetic radiation, pressure, etc.) acting on the skin. It mainly includes three cases: 1. The stimulation intensity exceeds a certain degree (sunburn). 2. Enhanced skin sensitivity (exogenous photosensitive dermatitis). 3. Reduced skin tolerance (threshold) - (chronic photosensitivity). basic knowledge The proportion of illness: 0.002% Susceptible people: no special people Mode of infection: non-infectious Complications: skin cancer
Cause
Cause of physical skin disease
Self-organic factors (30%):
Pathogenic microbial infections and toxins produced by the body, metabolic disorders of the body, imbalance of immune function, endocrine disorders, metabolic disorders of free radical toxins, and even indirect or direct relationship with pathological changes of the mind and nervous system.
Mechanical external cause (25%):
Such as sputum, rubbing erythema, trauma, etc., the skin of the body has changed.
Physical external factors (25%):
Such as frostbite, burns, sunburn, radiation dermatitis and so on.
Chemical external factors: (15%):
Most contact dermatitis is caused by exposure to chemicals such as dyes and chemical raw materials.
Other factors (5%):
Age, gender, occupation, season, environment, lifestyle and other factors also have a certain relationship with the occurrence of skin diseases.
Prevention
Physical skin disease prevention
Avoid the environment too wet, the temperature is too high, the clothing should be wide, reduce sweating and facilitate the evaporation of sweat, change clothes frequently;
Prevention of sunburn should first avoid exposure to strong sunlight, and should be gradually increased to gradually increase the amount of exposure. Treatment is generally symptomatic, and topical protective agents such as various emollients, calamine lotion, corticosteroid creams, etc. can be used.
To prevent the occurrence of allergic skin diseases, you should try to eat a high-protein, high-calorie diet. People with a history of allergies should try to avoid places where flowers and trees are flourishing. Wear long-sleeved pants, shoes and socks when going out for an outing. Desensitizing drugs. In case of itchy skin, body heat, cough, shortness of breath, you should leave this place quickly. If the symptoms are mild, you can take oral desensitizing drugs. If you have asthma symptoms, you should go to the hospital for treatment.
Complication
Physical dermatological complications Complications skin cancer
May cause skin cancer, may also cause skin atrophy or skin pigmentation.
Symptom
Physical dermatological symptoms Common symptoms Frostbite corns palmar keratosis excessive palm toe skin yellow keratin
Skin damage caused by physical factors such as mechanical friction is called physical skin disease.
Eyelet
It is a conical keratinous hyperplasia caused by local long-term compression or friction.
Clinical manifestations: The skin lesions are light yellow conical horny plugs, the tip of which is deep into the skin, and the base is exposed on the surface like a corn. When walking or standing, the pain is caused by the pressure on the distal end of the dermis. Occurs in the soles of the feet and toes, more common in young adults, slower course, not easy to heal.
2.
Commonly known as hadron. It is a keratinized patch caused by local long-term compression or friction.
Clinical manifestations: The lesions are round or irregularly shaped keratinized plaques, yellow, smooth surface, unclear borders, hard to touch, and obvious tenderness. It occurs in areas such as the soles of the feet and the palms that are easily pressed and worn.
Histopathology: Excessive keratinization of the epidermis can exceed several times the normal stratum corneum and the dermis is normal.
Hemorrhoids
More common in long-term bed rest and paralyzed patients, due to local tissue vascular nerve compression, affecting blood supply, nutritional disorders, leading to full-thickness skin necrosis.
Clinical manifestations: early skin flushing or paleness, blisters and rubs later, and finally formed deep ulcers. It is easy to secondary infection and even cause sepsis. It happens in the protruding parts of the contact bed, such as the appendix, hip and shoulder.
Frostbite
Clinical manifestations: Inflammatory changes in the skin caused by cold are called frostbite, which occurs every winter. Occurs in the extremities, especially in the fingers, toes and auricles. The local skin is dark red, purple red lumps or induration, and severe ulceration or even black necrosis.
Examine
Physical skin disease examination
Physical examination
Focus on the distribution of lesions, the type, size, size, shape, surface and substrate of the lesions, color, blister content and its color, arrangement characteristics and boundaries are clear.
The auxiliary physical inspections are:
(1) slide film examination method: the slide is pressed hard on the damage for 10 to 20 seconds, the color of inflammatory erythema and hemangioma can disappear.
(2) Skin scratches: Use a blunt instrument to scratch the skin, such as a wheal at the crossing, called skin scratching positive.
(3) Sensory examination: including temperature, touch and pain.
(4) Filtered by ultraviolet light: If the jaundice is dark green, the white sputum is bright green.
(5) Acanthosis cell release phenomenon examination method (Niss's sign): The blister spreads to the surrounding area, and the normal skin is pushed and the normal appearance of the blister is rubbed off and is positive.
2. Laboratory examination
(1) Skin histopathological examination: Some skin diseases have their own pathological changes, which can be diagnosed and differentially diagnosed accordingly.
(2) Skin test:
1 spot towel test. Used to check for contact allergens.
2 scratch test or piton test. Used to determine if a substance has an allergic reaction (type I).
3 leprosy test. It is used to judge the immune status of leprosy patients.
4 sputum test. Helps diagnose the bacillary rash.
(3) Microbiological examination: Examination of dermatophytes, leprosy, and plague helps to diagnose the corresponding skin diseases.
Diagnosis
Diagnosis and identification of physical skin diseases
diagnosis
Diagnosis can be based on medical history, clinical symptoms, and laboratory tests.
Differential diagnosis
Differential diagnosis of solar dermatitis: systemic lupus erythematosus, in addition to skin lesions, more associated with other multi-system, multi-organ damage, anti-nuclear antibodies and erythematosus cells positive, underlying membrane immunoglobulin and complement deposition can be identified .
The differential diagnosis of scorpion should be differentiated from contact dermatitis: the latter has nothing to do with climate and has a history of exposure to chemicals. The damage is limited, asymmetrical, and the local redness is swollen.
Frostbite: Seen in winter and clinical features, diagnosis is not difficult, but should be differentiated from erythema multiforme. The latter damage is pleomorphic and slapping can be violated.
