Diagnosis of Autoimmune Blistering Diseases: Dermatopathology and Other Laboratory Updates.

Autoimmune blistering diseases (AIBD), an immunologically diverse group associated with intraepithelial or subepithelial blistering, can present with protean clinical or histopathologic findings. Accurate diagnosis is important to predict clinical course, stratify risk for certain associated systemic conditions, and determine patient eligibility for various therapies. While helpful clues can be gleaned from microscopic evaluation of tissue, definitive diagnostic changes are not always present. Therefore, it is important for clinicians and dermatopathologists to recognize the various clinicopathologic manifestations of AIBD, as well as the value and limitations of legacy and novel ancillary testing modalities.