Recrudescent herpes simplex infection mimicking primary herpetic gingivostomatitis.

We report six cases of recrudescent intraoral herpes simplex infection clinically indistinguishable from primary herpetic gingivostomatitis. All infections occurred in healthy children or young adults. Serological analysis demonstrated herpes simplex virus (HSV)-specific IgG at initial presentation, indicating that the infection was not a primary infection. Convalescent sera exhibited HSV-specific IgM and a rising HSV-specific IgG titre. These findings demonstrate that the initial clinical diagnosis of primary herpetic gingivostomatitis was erroneous and that what was actually being observed was widespread recrudescent intraoral herpes simplex infection.