[Miescher's cheilitis and lymphocytic clonal expansion: 2 cases].

INTRODUCTION: Melkersson Rosenthal's syndrome is a rare disease that classically combines: orofacial edema, peripheral facial paralysis and a plicated tongue. Miescher's cheilitis represents the monosymptomatic form of the disease. Its etiopathogenesis is unknown. We report 2 cases of Miescher's cheilitis during which the discovery of a monoclonal lymphocyte expansion raised the question of an eventual link between these two diseases.

CASE REPORTS: CASE No 1. A 30 Year-old man, without medical past history, had been followed up for 3 Years for Miescher's cheilitis. The supplementary examinations permitted elimination of an infectious cause, Crohn's disease, sarcoidosis or a contact allergy. A serum monoclonal IgG kappa was discovered fortuitously. An X-ray of the skeleton and the myelogram were normal. There was no detectable monoclonal rearrangement of the genes of the blood or bone marrow T or B-cell lymphocyte receptor. In the absence of progression towards a malignant blood disease three Years later, we concluded in a benign monoclonal gammapathy. CASE No 2. A 36 Year-old Algerian man, without past medical history, had been followed-up for 8 Years for a granulomatous macrocheilitis. The search for Crohn's disease, sarcoidosis or a contact allergy was negative and the diagnosis of an incomplete Melkersson Rosenthal syndrome was retained. The blood count revealed persisting hyperlymphocytosis in the blood. The etiological search for a hyperlymphocytosis showed a monoclonal rearrangement of the T-cell lymphocyte receptor genes in the blood lymphocytes. The myelogram was normal.

COMMENTS: Melkersson Rosenthal's syndrome is a rare granulomatous disease of the mucosa of the mouth. The etiopathogenesis of this affection is unknown and controversial, several case reports suggest that it could be a disease of immunological origin. A clonal T-cell lymphocyte population was revealed in the labial lesions of a 12 Year-old patient presenting with Melkersson Rosenthal's syndrome during a control visit, without the role of this lymphocyte population having been determined. We report two other cases associating blood lymphocyte proliferation and Melkersson Rosenthal' syndrome. This association is not necessarily fortuitous because of the rarity of the syndrome on the one hand and the uncommon nature of the detection of lymphocyte clones in young patients on the other. The presence of a clonal population can be interpreted in two manners: it can demonstrate chronic antigen stimulation, which with a super-antigenic effect leads to the expansion of a lymphocyte population making it detectable. The other hypothesis would be an increased secretion of cytokines by the lymphocyte clone provoking a granulomatous organization, as during granulomatous lymphomas.