Anal pruritus is a common local pruritus. The anus sometimes has slight itching, and if it is serious, it will become itchy over time. It is a common skin disease with local nerve dysfunction. Generally limited to around the anus, some can spread to the perineum, vulva or scrotum. It mostly happens at noon and in the old age of 20-40 years old, and there are fewer young people under 20 years old, which rarely happens to children. Men are more common than women, and people who are used to being quiet and not exercising often have this itching. The cause of secondary itching is obvious and easy to treat; Spontaneous or unexplained PA is difficult to cure and often recurs, accounting for about 50% of all patients.
Anal pruritus is more common in middle-aged people. Some are local symptoms of itching all over the body, but they are more common in the elderly. Itching confined to anus is mostly related to or secondary to anorectal diseases. Local inflammation and congestion make the skin circulation and temperature rise, and the buttocks are not easy to dissipate heat, which leads to increased perspiration, wet immersion and uncomfortable itching. First-time patients are often scalded by hot water or coated with corticosteroids for a long time. Although itching can be temporarily relieved, it can form a vicious circle of itching-bad stimulation-more itching for a long time, making local symptoms more severe. Eating spicy food can also cause anal pruritus, poor hygiene habits, not cleaning anus and perineum in time, and rubbing pants can aggravate itching. Poor dressing, wearing narrow underwear, or wearing underwear with uncomfortable texture, such as some chemical fiber fabrics or thick and rough, makes the sweat around the buttocks not easy to be distributed and rubbed, and can also induce anal pruritus. In anal pruritus, children are mostly pinworm patients, and female pinworm crawls out of anus to ovulate, which causes anal pruritus through mechanical stimulation.
According to the etiology, it can be divided into primary itching and secondary itching.
(1) Primary pruritus
Primary itching is not accompanied by primary skin damage, and itching is the main symptom.
(II) Secondary itching
Secondary itching occurs in primary diseases and various skin diseases, accompanied by obvious specific skin damage and primary lesions, and itching is often a symptom of primary lesions. Anal pruritus caused by anal fistula, anal eczema, condyloma, neurodermatitis, anorectal tumor, pinworm, etc. All fall into this category.
Anal pruritus was mild at first, and there was no obvious change in anal skin, mostly paroxysmal. Chronic patients have severe itching, which lasts a long time, especially at night. Excessive scratching or mechanical stimulation makes perianal skin grow thick and rough, anal folds deepen, scratches, blood scabs and exudates are found in some areas, and feces and dirt remain in the folds. What's more, it may be complicated with infection with pustules or purulent secretions, flushing and swelling. The lesion can spread to perineum, scrotum, vulva and even bilateral buttock skin. Clinical examination can find internal hemorrhoids, external hemorrhoids, mixed hemorrhoids, anal fistula, or diabetes, pinworm disease, Candida albicans infection and so on.
According to the typical history of anal pruritus, combined with clinical symptoms and signs, it is not difficult to diagnose this disease, but it is difficult to find out the cause. Generally, primary diseases of anus become secondary itching, otherwise it is primary itching. In addition, a general physical examination should be carried out, and necessary laboratory tests should be done, such as blood, urine and stool routine, liver and kidney function, urine sugar and blood sugar, glucose tolerance test, biopsy and smear.
1. Treat primary diseases or complications, such as hemorrhoids, anal fistula, pinworm disease, etc. Give corresponding antibiotics or antibacterial drugs to treat complicated infection.
2. Avoid inappropriate self-treatment. Many patients with anal pruritus are unwilling to go to the hospital and take improper self-treatment, such as scalding with hot water, topical high-concentration corticosteroids or anti-stimulation drugs, and some simple home physiotherapy instruments. These methods do more harm than good, and can only temporarily inhibit itching, which will lead to prolonged pathological changes. Patients should be advised to stop using them.
3. Pay attention to hygiene, and don't eat or eat less irritating food, such as spicy food, strong tea and strong coffee, strong liquor, etc. Clothes and trousers should be loose, and underwear should be cotton.
4. The drug treatment of localized anal pruritus should be based on local external use. All kinds of drugs used in systemic therapy, such as corticosteroids, anti-inflammatory mediators and sedatives, have no obvious antipruritic effect on anal pruritus, but they all have many side effects or adverse reactions, so they should be avoided when there is no clear indication.
5. For those with local itching and normal anal skin, wash the anus with 4% boric acid water and apply cold compress. If ice cubes are added, the water temperature will be kept at about 4 ~ 5℃. Patients can apply gauze or absorbent cotton to the anus in a squatting position to immediately relieve itching. Once a day, 5 minutes in the morning and 5 minutes each time. After cold compress, dry the part with a dry towel, apply ordinary talcum powder and keep it dry. This type of anal pruritus is not suitable for external ointment, which hinders heat dissipation, and it is easy to induce itching by increasing sweat. Should choose cool and dry lotion, such as white dew, calamine lotion, etc.
6. Most patients with lichen lesions with rough and thick anal skin are complicated with infection, and appropriate antibiotics or antibacterial agents can be used. After infection control, local blocking treatment can be implemented; After local cleaning, use alcohol or bromogeramine solution for local disinfection, use prednisolone injection or triamcinolone acetonide injection for injection, drop the liquid medicine on the skin lesions with an injection needle, so that the skin lesions are fully immersed in the liquid medicine to relieve itching of patients, dry the local liquid medicine, and then apply ordinary plaster or ointment containing antipruritic agent according to the size of the skin lesions, or use film-forming agent or gel containing drugs as film wrapping. This method is suitable for going to bed. After 6 ~ 8 hours, remove the hard paste or film-forming cyst, clean the local area, and apply dry lotion or antipruritic aerosol spray. This method has a good effect on relieving itching and promoting the regression of lichen lesions.
7. Injection therapy is to inject drugs under the skin or in the skin, destroy sensory nerves, relieve local feelings, eliminate symptoms and cure local injuries. About 50% of cases can be cured permanently. However, patients with severe itching are prone to relapse and need to be injected again. Injecting drugs can not only destroy sensory nerves, but also motor nerves. Sensory anal incontinence and sphincter dysfunction often occur, but they can recover after a period of time.
⑴ Subcutaneous injection of alcohol: Alcohol can dissolve nerve myelin sheath without damaging nerve axis, denature sensory nerve endings and make skin lose sensation until nerve regeneration. There are two methods of injection. ① Subcutaneous injection in different areas: divide the anus into 4 areas, and inject 1 area each time. After skin disinfection, inject 5 ~10ml 1% or 2% procaine solution subcutaneously with a long needle, leave the needle in place, and then inject 5 ~10ml 95% alcohol. The injected drugs should be evenly distributed, without outflow and tension. Nor can it be injected into the skin to avoid skin necrosis; It is not advisable to inject anal sphincter to prevent sphincter paralysis. Hot compress after injection, sedative to relieve pain, interval of 5 ~ 10d, then inject another area 1, and completely inject area 4. ② Multiple subcutaneous injections: After local anesthesia, inject 3 ~10 ml of 95% alcohol subcutaneously around anus with a distance of 0.5cm, and inject 2 ~ 3 drops into each area to avoid injecting into skin or sphincter.
⑵ Intradermal injection of methylene blue: inject 0.2% methylene blue solution into perianal skin to make the feeling of internal nerve endings disappear and itching subside. The injection is made of 0.2g methylene blue and 0.5g procaine dissolved in 100ml distilled water, and the anal skin is coated with mercuric chloride solution. Inject the solution into the perianal skin with a fine needle, inject 3 ~ 4 drops at each place, and inject all the itching parts. The total amount cannot exceed 20ml. After injection, the anus should be covered with sterile gauze, and morphine or codeine should be used to relieve pain.
8. Surgical treatment
Spontaneous itching can be treated surgically if it has not improved or recurred many times after the above treatment. There are two surgical methods: denervation of anal skin and excision of anal skin.
⑴ Subcutaneous incision: make a semicircular incision 5cm away from the anal margin on both sides of the anus, cut subcutaneous fat, separate the flap inward to expose the lower edge of the external sphincter, and separate the skin of the internal sphincter into the anal canal to the plane of the anal flap. Then the skin on both sides of the anus is separated from the deep tissue to make the wounds on both sides of the anus communicate. Finally, the skin at the outer edge of the incision was separated outward 1 ~ 2 cm. After hemostasis, suture the skin graft in place, sometimes drainage is needed, and the outer cover presses the dressing. Intestinal preparation should be made before operation, and defecation should be controlled 3 ~ 4 days after operation. The results of each family are different, and most of them have achieved good results, but there are also reports of recurrent cases and wound infection and dehiscence.
⑵ Resection and suture: make an incision around the starting point of anus, and make an arc incision outside the incision, including the diseased skin in the incision. The two ends of the incision are connected, and the half-moon skin between the two incisions is excised to suture the wound. Remove the opposite side in the same way. After removing the skin, itching can stop, but the wound sometimes becomes infected.
In addition, pinworm can also cause perianal itching, but if it doesn't work after eating pesticides, it shouldn't.
And perianal eczema. If it is topical hormone ointment, it will be good for 2 days. Once the drug is stopped, it will recur, and the hormone ointment has great side effects, which will lead to repeated illness!
Pay attention to perianal hygiene, try to keep it clean and dry, and avoid alcohol and spicy food!
It is recommended to go to a regular hospital for detailed examination and treatment.
I wish you a speedy recovery! !