Melkersson-Rosenthal syndrome--a challenge for dermatologists to participate in the field of oral medicine.

Melkersson-Rosenthal syndrome (MRS) is a neuro-muco-cutaneous disorder involving remittently both the oro-facial innervation and muco-cutaneous tissues in a pathosis of complex origin characterized by recurrent edema, facial or other palsies, and nerval dysfunctions frequently associated with plicated tongue. Biopsies taken from the edematous tissues often reveal a temporary pattern of moderate epitheloid granulomatous inflammation scattered scarcely within remarkable tissue edema. However, this histological pattern is not a prerequisite for the diagnosis of MRS. The disease usually runs an intermittent and unpredictable course over years or decades and may have, if the edemas involve the tongue or the central nervous system, an ambiguous outcome. Greatly disfiguring oro-facial swellings often result from secondary persistence of the primarily recurrent edemas. A classification on grounds of different 'major' and 'minor signs' of MRS is proposed in the present paper. In recent years, novel therapeutic approaches involving either oral clofazimine or laser beam acupuncture (according to the principles of traditional Chinese medicine) have proven to be successful in some cases of MRS. Dermatology could play a larger role in oral medicine by taking diseases such as MRS into account in studies among specialties dealing with oro-facial pathoses.