Melkersson-Rosenthal syndrome is a rare form of hereditary angioedema characterised by a triad of symptoms of which incomplete (oligo- or monosymptomatic) forms have been described, frequently associated with dysreactive diseases or neoplasia. The authors describe the case of a 48-year-old man with an incomplete form which was successfully treated with steroids and, after a careful and detailed revision of the literature on the subject, they make a number of etiopathogenetic, histopathological, clinical and therapeutic comments.