What are the principles for the prevention and treatment of perianal eczema

As the name suggests, perianal eczema occurs in the skin around the anus, and in rare cases it may also affect the genitals. Symptoms of the disease include unbearable itching. The cause of the disease is also relatively complicated, usually caused by the interaction of multiple factors, such as external stimuli, friction between pants and the affected area, temperature, and even animal hair can sometimes trigger this eczema. Specifically, it manifests as dense, millet-sized papules, papulovesicles, or small blisters that are red in color. Small ulcers will appear after scratching. The following is an introduction to treatment:

1. General prevention and control principles

(1) To find the cause of the disease as much as possible, it is necessary to have an in-depth understanding of the patient's work environment, living habits, diet, hobbies, thoughts and emotions, and conduct a comprehensive examination of the whole body to check for chronic lesions and internal organ diseases in order to eliminate possible pathogenic factors.

(2) Avoid various external stimuli, such as hot water washing, violent scratching, excessive washing, and other substances that the patient is sensitive to, such as fur products.

(3) Avoid foods that are allergenic and irritating, such as fish, shrimp, strong tea, coffee, alcohol, etc.

(4) Explain the key points of protection to the patient in detail, guide the use of medication, and encourage the patient to cooperate with medical staff to give full play to the patient's subjective initiative.

2. Internal therapy

Western medicine can use antihistamines to relieve itching. In case of acute or subacute generalized eczema, 5% calcium bromide, 10% calcium gluconate or 10% sodium thiosulfate solution can be injected intravenously once a day, with 10 times as a course of treatment. For patients with widespread infection, effective antibiotics should be used in combination. In addition, B vitamins, vitamin C and drugs that regulate nerve function are also helpful.

Oral or injected glucocorticoids are generally not recommended. Although hormones have a quick effect on reducing inflammation, itching and reducing exudation, they quickly relapse after discontinuation, and long-term use can easily cause many adverse reactions.

3. Topical therapy

The principles are the same as for the treatment of contact dermatitis. Choose appropriate dosage form and medicine according to the condition of skin lesions. For small-scale subacute eczema, the application of glucocorticoid cream and tar preparations for external use is more effective.

Clinical manifestations

It is limited to the skin around the anus and may affect the perineum in a few cases. The itching is unbearable. It is often moist, the skin is infiltrated and thickened, and cracking may occur. In the acute phase, the rash is composed of numerous densely packed millet-sized papules, papulovesicles or small blisters with a flushed base. Due to scratching, the skin lesions may show obvious punctate exudation and small erosions. The center of the lesion is often heavier and gradually spreads to the surrounding area. There are also scattered papules and papulovesicles on the periphery, so the boundaries are unclear. When combined with infection, the inflammation may be more obvious and form pustules, pus oozing out or yellow-green or dirty brown scabs. It may also be combined with folliculitis, furuncle, local lymphadenitis, etc.

Subacute eczema occurs when the inflammation of acute eczema is alleviated, or if the acute phase is not promptly and appropriately treated and is delayed for a long time. The skin lesions are mainly small papules, scales and crusts, with only a few papulovesicles or small blisters and erosions. There may also be mild infiltration, and the patient still feels severe itching.

Chronic perianal eczema may develop due to repeated attacks of acute or subacute eczema, or it may present as chronic inflammation from the beginning. The skin of the affected area is infiltrated and thickened, turning dark red and pigmented, with a rough surface and covered with a small amount of bran-like scales, or scabs due to scratching. Some cases have varying degrees of lichenification, which is localized and has clear edges. There may also be scattered papules and papulovesicles on the periphery. During acute attacks, there may be obvious exudate. The subjective symptoms also include obvious itching, which often occurs in paroxysms. Because the skin loses its normal elasticity and is more active, it may crack and cause pain in the affected area. The course of the disease is uncertain, prone to relapse, and difficult to heal.