Anal itching (pruritus ani – PA) is an unpleasant sensation leading to scratching the skin around the anal oriface. The problem is often underestimated; it is embarrassing and can severely impair the patient’s quality of life. PA occurs in about 1-5% of the population, four times more often in men than women, most usually between the ages of 40-70 (1). It is a fairly common symptom occurring in the course of many systemic diseases, both dermatological and proctological. The etiology of itching in the anogenital distance is diverse; it can be associated with the most common proctological comorbidities – most often anal fissure or hemorrhoids. It also occurs in the course of various dermatoses such as allergic eczema, psoriasis inversa and lichen planus, also in infectious dermatoses, and it may be present as the so-called primary or idiopathic anal itching without any apparent reason (2). Other common causes include diaphoresis and inadequate crotch hygiene. The role of uncontrolled release of the mucus and fecal content and of excessive vaginal discharge in women is also stressed. It has been demonstrated that higher incidence of pruritus occurs in those patients who consume large amounts of coffee, chocolate, Coke, citrus fruits, milk and dairy products, and alcohol, particularly beer (3). It should also be emphasized that this ailment is often reported by those patients who overuse hygienic agents, cosmetics and topical drugs containing preservatives, local anesthetics and antibiotics (4).

The aim of this study was to evaluate the potential etiologic factors in adult patients with persistent anal pruritus.

The study included 55 patients of both sexes aged 20-79 who reported persistent anal itching present for at least four weeks and who were admitted to the Dermatology Outpatient Clinic and Specialist Proctological Office in 2011-2014.

After obtaining the patients’ consent for inclusion in the study, those subjects with pruritus ani who did not report a proctological disease were qualified into the study group. Enrolment was carried out on the basis of: dermatological examination, proctological examination (anoscopy, rectoscopy), laboratory tests, bacteriological and mycological smears collected from the anogenital distance, and epidermal tests.

Before treatment inclusion, each patient was subjected to laboratory tests: blood count with differential blood smear, bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood glucose, urinalysis, stool examination for parasites and EIA for lambliasis, and swabs from the anal area (bacteriological and mycological swabs).

Certified patch tests (Chemotechnique Diagnostics, were performed for Polish Baseline Series, external medications and cosmetics. Test reading was conducted during visits after 48, 72 and 98 hours. Two patients underwent a histopathological examination of skin specimen due to unclear clinical pictures.

The study group comprised of 21 women and 34 men. After a thorough diagnosis, a proctological disease was excluded in all the patients, with 47.2% (26 subjects) diagnosed with contact eczema on the skin around the anus (fig. 1, 2). The most frequently repeated allergens included nickel, fragrance mixes, neomycin and paraben mixes. Idiopathic anal itching affected 25.4% of the patients (14 subjects) – in those subjects the lesions were often shallow linear cracks on the skin without inflammatory reaction; epidermal test results were negative; laboratory tests did not reveal any deviation. Three patients diagnosed with idiopathic anal itching had abundant pubic hair in the anogenital distance.