A case-control study of HLA alleles in Brazilian patients with Melkersson-Rosenthal syndrome.

Melkersson-Rosenthal syndrome (MRS) is a neuromucocutaneous disease that manifests by the triad of recurrent orofacial edema (frequently as cheilitis granulomatosa), relapsing facial paralysis and plicated tongue. The cause of MRS remains unknown, but genetic predisposal and a relationship with inflammatory bowel disease are suspected. The objective of this research was to compare the frequency of class I and II HLA alleles in patients with a confirmed diagnosis of MRS with those of a healthy control group. We conduct a case-control study and typed of HLA A, B, C, DR, and DQ using molecular techniques. The study included 36 patients with MRS and 297 patients in the control group. There was an increase in the expression of HLA A*02 (p = 0.0269; OR: 1,79 [1,045-2,973]), HLA DRB1*11 (p < 0,0001; OR: 4,009 [2,214-7,277]), HLA DRB1*13 (not statistically significant) and HLA DQB1*03 (p = 0,0177; OR: 1,829 [1,122-2,978]) and low levels of HLA A*01 (p = 0.0046; OR: 0,097 [0,009-0,538]), HLA DRB1*04 (p = 0.0274; OR: 0,228 [0,053-0,844]), HLA DRB1*07 (p = 0,0091; OR: 0,183 [0,043-0,670]) and HLA DQB1*02 (p = 0.0051; OR: 0,312 [0,143-0,721]) in MRS patients compared with the control group. Crohn disease (CD) patients had disparate genetic profiles versus those with MRS. This single-institution study had a small cohort, because this disease is rare. Conclusions: There is a genetic predisposition toward MRS, involving associated and protective genes.