Can pemphigus vulgaris be induced by nutritional factors?

We present an unusual case of oral pemphigus vulgaris (PV) in a 42-year-old woman, in whom the lesions regressed spontaneously upon each of four hospitalizations and relapsed at home. The inducing factor was found to be leek, which was the main constituent of her three meals a day. The diagnosis of PV was confirmed by IIF, immunoblot of epidermal extract and baculovirus recombinant PVA protein. A leek-free diet produced regression of oral lesions and a fall in pemphigus antibody titers to almost undetectable levels, whereas the leek challenge induced relapse and an increase of antibody titers. It is to be presumed that the leek-induced pemphigus in our case is comparable to pemphigus induced by penicillamine and captopril or other thiol drugs in genetically predisposed individuals. It is possible that drug-induced pemphigus, which does not regress after withdrawal of the offending compound, might be maintained by the nutritional factors, if their concentration exceeds the individual threshold of tolerance.