Introduction:

Diagnosing autoimmune blistering diseases is based on clinical presentation, direct immunofluorescence and detection of circulating autoantibodies. However, a histopathological examination of the affected tissues may also be helpful in such a diagnosis.

Objective:

To present a case illustrating that a histopathological examination facilitates the diagnosis of autoimmune blistering diseases, particularly for a patient with concomitant dermatological conditions.

Case report:

We present the case of a 91-year-old female patient with symptoms of generalized scaly, crusted erosions on an erythematosus base, who was diagnosed with psoriasis 10 years earlier. Based on a histopathological examination, there was a suspicion of pemphigus foliaceus, which was later confirmed by direct immunofluorescence and the multiparametric ELISA.

Conclusions:

A histopathological examination is not obligatory for a pemphigus diagnosis; however, in ambiguous cases, where a patient has other concomitant dermatoses, it may significantly improve the accuracy of the diagnosis. The limitations and advantages of histopathological examinations in pemphigus are discussed.