Case for diagnosis: vesicular pemphigoid?

A 47-year-old man was diagnosed as having dermatitis herpetiformis (DH) in 1957. His failure to respond to therapy and the advent of immunofluorescent techniques led to a subsequent tentative diagnosis of vesicular pemphigoid (VP). High-titered, antibasal zone antibodies were present. However, unlike previously reported cases, direct immunofluorescence microscopy initially showed a DH-like and, later, an atypical granular band instead of a tubular (linear) band but with bullous pemphigoid (BP)-like immunoglobulin composition. No IgA was present. The patient's serum antibasal zone antibodies reacted with his perilesional skin despite granular deposits present at the same site, suggesting concomitant BP- and DH-like immunologic phenomena. The non-IgA-containing atypical granular band might be an immunologic marker for a subset of VP or another distinct disease entity demonstrating an immunologic overlap between BP and DH.