[Acute and chronic anal ulcers].

Classic types of anal ulcers are acute and chronic anal fissure. Characteristic symptoms of chronic fissures are severe pain during defecation accompanied by the triad of ulceration, hypertrophic anal papilla and external skin tag. If the symptoms deviate other causes of ulceration must be considered. Primarily, malignancies should be excluded. The special setting in the anal fold, especially with concurrent immunosuppression, could lead to nonspecific manifestations of different proctological, dermatological and infectious diseases, which can only be clarified by further diagnostic workup and histopathology. Only the correct diagnosis will lead to causal and effective therapy. Successfully treated inflammatory dermatoses and precancerous lesions require regular follow-up because a recurrent or persistent course of the disease may result in malignant transformation.