Diagnosing pemphigus foliaceus: A retrospective analysis of clinical, histological and immunological criteria

Background: Clinical, histological and immunological criteria distinguish pemphigus foliaceus (PF) from pemphigus vulgaris (PV), but whether and how often they are concordant in the same patient is unknown. Methods: Seven clinical records were selected from two hospital settings for having a diagnosis of PF and the initial serum and histopathological specimens still available. Controls were 8 PV records selected in the same way. Histopathological slides were re-evaluated. Stored sera were studied by indirect immunofluorescence (IIF), Western blot and ELISA. Results: Acantholysis was superficial in all PF patients and deep in all PV patients. Mucosal lesions were not exclusive of PV. IIF was positive in 43% of PF patients. Western blot revealed desmoglein 1 in 86% of PF patients and in 25% of PV. ELISA revealed anti-desmoglein-1 antibodies in up to 71% of PF and in 62% of PV patients, in 1 failing to detect anti-desmoglein-3 antibodies. Conclusions: Histopathology remains the most reliable criterion for diagnosing PF. Western blot and ELISA, especially in combination, may be only of confirmatory value.