What blood tests are needed for skin diseases

What blood tests are required for skin diseases?

Skin diseases bring inconvenience to our lives. Skin diseases must be discovered and treated early, so that recovery is good and the skin disease can be avoided from being seriously affected by the treatment. Skin diseases require detailed examination in the dermatology department of a large hospital. Some skin diseases can be diagnosed by naked eye examination, such as vitiligo. Some skin diseases require blood tests to be diagnosed. Many people do not know which blood tests are included in skin disease blood tests. Which blood tests are included in skin disease blood tests? Let’s take a look at it next.

1. What are the blood tests for skin diseases?

The diagnosis of skin diseases, like other diseases, must be based on a comprehensive analysis of medical history, physical examination, and laboratory tests:

1. Ask about medical history

The dermatologist should focus on asking the patient whether he or she has any symptoms and how long and how severe they are, the common sites of skin lesions and the order, distribution, morphology, color, and whether the patient has other diseases or has taken medications before the onset of the disease, whether the patient has systemic symptoms, whether the disease is related to the season, climate, living and working environment, diet, etc., whether there are similar skin diseases in the family, and the diagnosis and treatment after the onset of the disease and the efficacy of the treatment.

2. Physical examination

(1) Focus on the distribution of skin lesions, the type, number, size, shape, surface and base of the lesions, color, the contents of the blisters and their color, arrangement characteristics, and whether the boundaries are clear.

(2) Auxiliary physical inspection

1) Slide pressure diagnosis method: Press the slide firmly on the lesion for 10 to 20 seconds, and the color of inflammatory erythema and hemangioma will disappear. It can be used to differentiate erythema and purpura, and to observe lupus nodules.

2) Dermatographism: If a wheal is produced at the scratched area by scratching the skin with a blunt instrument, it is called a positive dermatographism. Patients with urticaria often test positive, and atopic dermatitis and erythroderma have an anemic reaction with pale skin when the skin is mechanically stimulated.

3) Sensory examination, including temperature, touch and pain sensation.

4) Filtered ultraviolet light examination: The hair of patients with tinea versicolor will show dark green fluorescence, while that of patients with tinea alba will show bright green fluorescence. Other diseases, such as tinea versicolor, porphyria, etc. can emit different colors of fluorescence.

5) Acantholysis sign (Nikolsky sign): The test is positive if the blisters spread to the surrounding areas, the normal skin is pushed and the normal-looking skin between the blisters is wiped off.

3. Laboratory examination

(1) Pathological examination of skin tissue: Some skin diseases have their own unique pathological changes, which can be used to confirm and differentially diagnose.

(2) Skin test

① Patch test

Used to detect contact allergens.

② Scratch test or intradermal test

Used to check immediate allergic reactions and determine whether a substance has an allergic reaction (Type I).

③ Leprosy test

Used to determine the immune status of leprosy patients.

④ Trichoderma test

It helps in the diagnosis of ringworm rash.

(3) Microbiological examination

Examination of skin fungi, leprosy bacteria and scabies is helpful in diagnosing the corresponding skin diseases.

II. Treatment

Topical medications are the most commonly used treatment for skin diseases. If topical medications are not selected or used properly, they are often ineffective and may even make the condition worse.

When choosing topical medications for skin diseases, you should pay attention to the following aspects: The same drug has different dosage forms, such as solutions, pastes, powders, creams, lotions, ointments, tinctures and emulsions. Different dosage forms have different effects and indications, so different dosage forms of topical medications should be selected correctly according to the clinical symptoms and characteristics of skin lesions at different stages of the disease.

1. In the general acute phase, when there is local redness, swelling, blisters, and erosion, liquid compresses are often used, which can have anti-inflammatory and heat dissipation effects. If there is exudation, use liquid compresses first and then oils.

2. When the skin lesions are in the subacute stage, the redness and swelling are reduced, and the exudate is reduced. Pastes, powders and lotions can be used as appropriate to exert anti-inflammatory, antipruritic, astringent and protective effects.

3. In the chronic stage, when the skin lesions thicken and become lichenified, creams, ointments, plasters, etc. can be used.

4. Pay attention to the time and frequency of taking medication for skin diseases. Medications and lotions evaporate easily and reduce their efficacy, so they need to be used more frequently, generally once every three hours; tinctures and ointments have long-lasting effects and can be used once in the morning and evening each day. The wet compress method should also be appropriate. Before using the medicine, in addition to cleaning the affected area, the scab should be disinfected and softened with cooking oil before wiping it off. If blisters with a diameter greater than half a centimeter are seen at the skin lesions, the contents should be extracted with a sterile empty syringe, while retaining the blister wall. Before applying the medicine to hairy areas, you should shave the hair first and then apply the medicine.

5. The selection of drugs should also take into account age, gender, site of disease and patient's physical condition. For example, low-concentration drugs should be chosen for elderly and young patients; when pregnant women use topical medications, the effects on the fetus and infants should be taken into consideration; high-concentration or highly irritating drugs should not be used on the face, breasts, and vulva, and should be used with caution by children and women; high-concentration drugs can be used on the palms, soles of the feet, etc.; for those with sensitive skin, use low concentrations first and then high concentrations. For new drugs or drugs that are prone to allergies, use them on a small area first. If there is no reaction, gradually increase the concentration and expand the area of ​​application as needed.

3. Reminder

Physical therapy is also a commonly used treatment for skin diseases. Commonly used physical therapies include: electrotherapy, light therapy, microwave therapy, cryotherapy, laser, hydrotherapy, and radiotherapy.