Not So Normal Skin: A Review of the "Random" Skin Biopsy.

The diagnosis of dermatologic conditions typically hinges on the examination of visibly apparent skin abnormalities. On occasion, dermatologists can aid in diagnosing the "invisible" by performing biopsies of skin that seems clinically normal, with the hope that histologic clues only apparent in tissue samples-and not by the naked eye-may yield helpful diagnostic information. This narrative review discusses the utility of random, normal skin biopsy in the diagnosis of a variety of conditions for which this method has been described. Herein, we review the available literature on the use of normal skin biopsy for Alport syndrome, amyloidosis, atypical hemolytic uremic syndrome; cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy, intravascular lymphoma, lysosomal storage disorders, pseudoxanthoma elasticum, rabies, and small fiber neuropathies.