To the Editor.—
I found the report of Drs. Demento and Grover in the Archives (107:883, 1973) very interesting. Isolated reports in which features of pemhigus and dermatitis herpetiformis have overlapped have appeared from time to time. The confusion engendered by these reports gave rise to the myth that dermatitis herpetiformis could sometimes transform into pemphigus. Rook and Whimster1 stated that until a case could be produced that at one stage showed the unequivocal histologic changes of dermatitis herpetiformis and at a later stage those of pemphigus, it could not be held that dermatitis herpetiformis transformed to pemphigus. The real cause for this confusion was inadequate information, a point emphasized by Piérard2 in discussing such a case, which he considered had been pemphigus from the onset. One of the sources of inadequate information is the bad habit of recording the histological findings as `typical of' or `consistent with'
Alexander JO. Pemphigus vs Acantholytic Herpetiform Dermatitis. Arch Dermatol. 1975;111(6):794-795. doi:10.1001/archderm.1975.01630180122025