Myenteric antiplexus antibodies and class II HLA in achalasia.

Achalasia, a motor disorder of the esophagus, is accompanied by autoimmune phenomena that could be playing a role in the pathogenesis of the disease. Our objective was to establish the genotypic frequency of the HLA-DR and DQ alleles in patients with achalasia and to establish their relationship with the presence of myenteric antiplexus antibodies in our geographic area. A total of 92 patients diagnosed with achalasia and two control groups with 275 healthy subjects were studied for HLA typing and 40 for autoantibodies determination. The myenteric antiplexus antibodies were positive in 50 patients (54.3%) and in 3 healthy subjects (7.5%) (P < 0.001). The patients showed a significantly higher frequency of DQA1*0103 and DQB1*0603 than was found in the controls. The heterodimer DQA1*0103-DQB1*0603 was increased in the patients [odds ratio (OR) = 2.57]. In regard to the association between the HLA DQA1 and DQB1 alleles and the antiplexus antibodies, these antibodies were found in greater prevalence in those patients with the DQA1*0103 and DQB1*0603 alleles, and the differences were statistically significant (OR = 3.17 and OR = 5.82, respectively). All of the women and 66.7% of the men with achalasia and the DQB1*0603 allele or the DQA1*0103-DQB1*0603 heterodimer were positive for antibodies.