[Skin changes of the penis. Differentiation between local findings and systemic diseases!].

In the event of diseases affecting the penis, both patient and doctor may first have to overcome a certain "threshold of inhibition". Since, however, the clinical examination of the genitals is uncomplicated and informative, the general practitioner should be familiar with the major pathological conditions that may affect the male organ. Diseases of the penis can take the form of a local condition or be part of a generalized cutaneous disease. Examples of the latter that frequently involve the penis are psoriasis and lichen planus. Infections are caused by bacteria, fungi, viruses or parasites, and Candida, streptococci and anaerobes need particular mention. Other major differential diagnoses are cutaneous drug reactions, contact dermatitis and neoplastic lesions. But, excessive hygiene may also cause problems ("over-treatment balanitis").