[Pruritus and prurigo]

Prurigo occurs in the acute form of the disease (strophulus), in the subacute frorm (prurigo simplex subacuta), and the chronic form (prurigo nodularis Hyde). Transition stages between the subacute and the chronic form of the disease are common. Strophulus is characterized by few papulovesicles, which are disseminated on the trunk. Likewise, the lesions of prurigo simplex subacuta may be disseminated, or they may be acneiform, or are localised on the extremities only. Typically, prurigo nodularis Hyde occurs on the lower extremities. Strophulus is caused by the bites of insects or by gastrointestinal disorders. The causes of prurigo simplex subacuta include metabolic and endocrine disorders as well as skin diseases. The occurrence of the latter is demonstrated by the combination of atopic dermatitis and prurigo (prurigo diathetique Besnier). The metabolic and endocrine disorders include diabetes mellitus, hyperlipidemia, diseases of the liver, the stomach and the bowels, finally increased androgene levels in women. The same pathological conditions are found in prurigo nodularis Hyde. The extreme chronicity of the prurigo is most probably caused by the inefficiency of the therapy of internal diseases.