Nonvenereal perianal conditions.

A variety of conditions can affect the perianal tissues. Evaluation must include a thorough history, which should emphasize hygienic habits, use of topical and oral medications, and a review of systems with particular attention to gastrointestinal symptoms. Examination of other areas of the skin may provide clues to the correct diagnosis. Examination of scrapings for yeast, more rarely dermatophytes, and Tzanck preparations from the base of blisters or erosive lesions are useful office diagnostic techniques. In some conditions biopsy of the involved area can be diagnostic (e.g., Paget's disease); in others it may indicate the need for additional studies. Direct immunofluorescent evaluation and special stains may also be indicated. Culture is important to define deep fungal and mycobacterial infections as well as more common bacterial infections. Proctoscopy and roentgenographic studies may be an important part of evaluation, especially in patients who present with perianal suppuration, masses, or anal fissures. Serologic tests for syphilis cannot be overlooked when lesions are ulcerative, moist, or papillomatous. It must be remembered that the symptoms related to perianal eruptions are nonspecific. It is only with a high index of suspicion and careful evaluation that the correct diagnosis can be established.