Pruritus Ani

Introduction
Signs and Symptoms
Etiology and Treatment

Introduction
Pruritus Ani is so common today that it is known as the "Space-age" disease. Occasionally, pinworms, lice, fungus, and hemorrhoids may be responsible. Rarely, food allergies, and allergies to drugs such as antibiotics may be the cause. Pruritus ani is also associated with certain systemic disorders such as jaundice, diabetes, lymphoma, and uremia. Pruritus ani is a self-perpetuating disease: scratching causes further irritation, which becomes a new source of itching. The cause of pruritus ani may be difficult to determine, thus making pruritus ani a potentially difficult conditions to treat.

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Signs and Symptoms
Itching, particularly at night. Skin changes occur which are due in part to scratching hyperemia, excoriations, abrasions, thickening, and lichenification.

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Etiology and Treatment
Treatment varies widely, depending on the actual cause of the pruritic condition. In almost every case, anal hygiene is reassessed, and careful attention is given cleanliness and soft gentle wiping after bowel movements. Balneol® is a product specially formulated with emollients to cleanse and soothe the perianal and external vaginal areas after wiping.
Topical hydrocortisone medication applied daily is frequently prescribed, and in most cases the problem gradually dissipates within a few short weeks.

One of the main problems with treatment is that the disease is self-perpetuating and made worse by scratching and rubbing. Intense itching causes the patient to scratch the area. Scratching and rubbing off superficial layers of skin makes the itching worse – and causes the patient to scratch more. As the perianal skin begins to break down, the protective layers of skin begin to ooze interstitial fluid. The area then becomes moist, and susceptible to a fungal infection. Open sores made by scratching, then become susceptible to infection by bacteria.

Using a protective moisture barrier cream or ointment, may help prevent skin irritation from direct contact with stool. In the event that there is a fungal component to the skin irritation, antifungal medications should be added to the treatment regimen. In the event that there is a bacterial component to the skin irritation, antibacterial medications should be prescribed as well. Vytone® is an antifungal, antibacterial, and corticosteroid combination that may be useful because it can treat symptoms of itching as well as many causes of perianal skin irritation.

Warm, moist environments are ideal for allowing the growth of fungi and bacteria. In the event that the perianal area is irritated by a constant feeling of wetness, bow dry the area after a shower, and place some cotton batting in between the buttocks for dryness. Zeasorb Powder® is a superaborbent powder that may also be of use. This product does not contain cornstarch, which is food for bacteria and fungi, and needs to be avoided. In the event of hyperhidrosis in the perianal area, a prescription antiperspirant containing aluminum hexahydrate or aluminum chloride may be helpful.

Dietary indiscretion, the use of antibiotics, or an infection, may alter the pH (measure of the acidity or alkalinity of a solution) of the intestinal tract. A simple stool acidity test can be helpful to diagnose the problem, but lacks specificity and should not be relied upon. An increase in pH (alkalinity) allows the intestinal tract’s normal protective mechanism to depart, and permits the proliferation of minority fungi and bacteria. To correct this, the diet can be altered to avoid high alkaline foods and fermentable type of foods such as citrus juices, beer, wine, and carbonated beverages. Friendly bacteria in the form of Lactobacillus Acidophilus is reintroduced into the intestinal tract, taken orally 4 times a day for 7-10 days. And the patient is instructed to bathe the area with a mild astringent like Domeboro’s® solution, or a dilute vinegar solution, before bedtime for 7-10 days.

Last but not least, the patient needs to be examined for food allergies and sensitivities. Blood eosiniphile and RAST (radioallergosorbent test) testing may be useful to help identify a wide variety of food allergies, and their levels of sensitivity. Lactose intolerance (the inability to digest significant amounts of lactose, the predominant sugar of milk and cheese) can be a common cause of pruritus ani. Antihistamines may help neutralize the effect of some allergens. Foods not well tolerated should be avoided.

Because the cause of pruritus ani may be difficult to determine, these treatments be tried either empirically or systematically, until satisfactory results are achieved.

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