The histopathological spectrum of Melkersson-Rosenthal syndrome: Analysis of 47 cases.

BACKGROUND: Melkersson-Rosenthal syndrome (MRS) is a rare disease characterized by the triad of recurrent orofacial edema, relapsing facial paralysis and plicated tongue. Histopathological features of MRS have not been extensively analyzed. METHODS: This study investigated the histopathological aspects of oral lesions from 47 MRS patients. RESULTS: The most common biopsy site was the upper lip, followed by the lower lip, gingiva and palate. The most important findings were ill-defined and well-formed granulomas. Lymphoplasmacytic inflammatory infiltrate was seen in early and late stages of MRS. Edema, fibrosis, vasodilatation and congestion were the most common finding in the lamina propria. Gingival and palate exams also demonstrated granulomatous infiltrates. Regarding the evolution time of the disease, we demonstrated that, in initial phases, there is a lymphoplasmacytic inflammatory infiltrates, followed by a granulomatous infiltrate and, subsequently, fibrosis. CONCLUSION: Histopathological examination of oral lesions is helpful for the diagnosis of MRS; the absence of granulomatous inflammation does not exclude the diagnosis of syndrome. Clinical and histopathological analysis of the rare gingival and palate lesions is important, since all histopathological findings of the disease were detected in these sites.