Pruritus ani: diagnosis and treatment.

Pruritus ani is a common condition with multiple causes. Primary causes are thought to be fecal soiling or food irritants. Secondary causes include malignancy, infections including sexually transmitted diseases, benign anorectal diseases, systemic diseases, and inflammatory conditions. A broad differential diagnosis must be considered. A reassessment of the diagnosis is required if symptoms or findings are not responsive to therapy. The pathophysiology of itching, an overview of primary and secondary causes, and various treatment options are reviewed.