sunburn
Introduction
Introduction to sunburn Solar Dermatitis, also known as sunburn, is a phototoxic reaction that occurs in the skin of the human body after excessive exposure to ultraviolet light in the sun. The disease is caused by intense UVB exposure in sunlight, and about half of the UVB is scattered through the atmosphere, so the disease can occur in foggy days. The pathogenesis of sunburn may be due to the energy transfer of light-sensitive substances or the binding of DNA to light energy. It may also be caused by cell membrane peroxidation, the degree of reaction, often with light. There are differences in intensity, duration and range of exposure, environmental factors, depth of skin color, and physical fitness. The research on this disease mainly lies in the discovery of chemical mediators of erythema inflammation. Prostaglandins, histamine, serotonin and kinins have been confirmed. The disease is more common in spring and summer. Children and women are prone to morbidity. basic knowledge Sickness ratio: 0.5% Susceptible people: no special people Mode of infection: non-infectious Complications:
Cause
Cause of sunburn
Physical factors (30%):
White skin is more sensitive to sunlight. People with white skin and dry skin are generally more sensitive to sunlight than oily skin and dark skin. In addition, certain diseases can be induced or changed after sun exposure, most notably lupus erythematosus. 30% of patients with lupus erythematosus are sensitive to sunlight. These patients should try to avoid sun exposure. They should use sunscreen, umbrella or wide-brimmed hat, wear light-colored long-sleeved tops and trousers. Avoid photosensitive drugs.
Ultraviolet radiation (35%):
Most of the sunlight is composed of visible light, and the spectral range is about 390-770 nm. In addition to its ability to stimulate the retina of the eye, it also has some biological activities. Above 770 nm is infrared light, which is an invisible hot line, which can make the skin redden. In the ultraviolet rays below 390 nm, the disease is caused by 290-320 nm medium-wave ultraviolet rays. The cause of this disease is 290-320 nm medium-wave ultraviolet rays. The degree of skin reaction varies depending on the irradiation time, range, environmental factors and skin color. Increasing the body's sensitivity to ultraviolet light, the incidence of this disease is also related to the individual's susceptibility, more common in the early spring and early summer, the plateau residents, snow exploration or water surface evildoers more.
Prevention
Sunburn prevention
Regularly participate in outdoor exercise to make the skin produce melanin to enhance the skin's sensitivity to sunlight. Try to avoid sun exposure. When going out, do protection such as umbrellas, straw hats, gloves, etc., and use other light-proofing agents. : such as reflective sunscreen, 15% zinc oxide ointment; 5% titanium dioxide emulsion; 5% p-aminobenzoic acid emulsion or elixir; 10% salo (salo) ointment, etc., can be rubbed on the exposed skin 15 minutes before exposure on. Strengthen skin nutrition, usually eat more fresh fruits and vegetables, eat some fat to ensure the skin's elasticity, and enhance the anti-wrinkle vitality of the skin. Vitamin C and vitamin B12 can prevent and reduce the body's sensitivity to ultraviolet light, and can promote the disappearance of melanin and restore the elasticity of the skin. Therefore, foods rich in multivitamins should be eaten in summer. Avoid eating photosensitizing foods to avoid recurrence of old diseases.
Complication
Sunburn complications Complications
The most common late complications are secondary infections, plaque pigmentation and scorpion-like rash. The skin is more susceptible to sunlight damage within one to several weeks after scaling.
Symptom
Symptoms of sunburn Common symptoms Sunburn erythematous rash blister or bullae damage erythema (border clear fatigue skin itching heart palpitations
When the skin is exposed to intense sunlight for several hours to ten hours, a rash occurs on the exposed parts such as the face, neck, back of the hand, etc. According to the severity of the skin reaction, it is divided into one-time sunburn and second-degree sunburn.
At one time, the sunburn showed diffuse erythema after partial sun exposure, and the boundary was clear, with a peak of 24 to 36 hours.
The second degree of sunburn is characterized by local skin redness and swelling, followed by blisters and even bullae, blister wall tension, blister fluid is pale yellow, and the symptoms are burning or itching. The blister is erosive after rupture, and soon it is dry and crusted, leaving behind Pigmentation or hypopigmentation.
The second day after sun exposure, the condition reaches a peak, which may be accompanied by fever, headache, palpitations, fatigue, nausea, vomiting and other systemic symptoms, which can be recovered after one week.
Examine
Sunburn examination
Skin examination can be seen in the exposed skin with obvious erythema on the border. In severe cases, edema may occur, reaching a peak at 12-24 hours, accompanied by local burning or stinging, and some may have local itching.
Diagnosis
Sunburn diagnosis
diagnosis
According to the history of sun exposure, the exposed parts of the skin are red and swollen or blisters, and the incidence is related to the season, and it is consciously burning and tingling.
The epidermis has individual necrotic keratinocytes to large confluent necrosis, vasodilatation of the superficial dermis, and infiltration of a small amount of lymphocytes around the blood vessels.
Differential diagnosis
The disease needs to be differentiated from contact dermatitis and niacin deficiency. Contact dermatitis: has a history of exposure to irritants, has nothing to do with sun exposure, can occur in any season, rash occurs at the contact site, consciously itchy, niacin deficiency: In addition to sun exposure, there are also rashes on non-exposed areas, often accompanied by symptoms of the nervous system and digestive system.
