Factors limiting the usefulness of histopathologic examination of skin biopsies in the diagnosis of large animal dermatoses.

Skin biopsy for histologic, immunofluorescent, parasitologic, and bacteriologic examination is a common procedure, but for maximum effectiveness the clinician must realize the importance of precautions to select the correct stage of lesion of different diseases; avoiding creating artifacts during removal and fixation; and give full details of history, clinical diagnosis, and differential diagnoses on the laboratory request sheet. Pathology reports describing the subtleties of histologic changes are difficult to write, particularly if the lesions are not specific. Overly long histologic reports without a definitive diagnosis may frustrate a clinician who is unfamiliar with the significance of histologic lesions. For these reasons, clinician and pathologist must develop a rapport and empathy for the other's difficulties and adequately communicate to allow each to make a maximum contribution toward the final diagnosis. Histopathologic examination of skin lesions may not produce a specific diagnosis but is frequently useful in the elimination of other suspected diagnoses.