HLA and enteric antineuronal antibodies in patients with achalasia

The aetiopathogenesis of primary achalasia is largely unknown, although an immunogenetic predisposition is suspected. To establish whether a correlation exists among possible aetiological factors, including class II human leucocyte antigen (HLA) alleles and autoantibodies to enteric neurones, and clinical features of patients with achalasia, a total of 60 patients and 200 healthy subjects were typed by high-resolution HLA-DQ and HLA-DR alleles. Circulating antineuronal antibodies were investigated by using indirect immunofluorescence on enteric neurones of rat ileum and colon and immunoblotting assay in a subset of achalasic patients and in all controls. The DQB1*0502 and DQB1*0601 alleles were significantly increased in patients with achalasia compared with controls (P < 0.03, P < 0.001, respectively). Moreover a negative correlation with the DQB1*0201 allele was found (P = 0.016). As a whole, 14 of 60 (23.3%) achalasia patients were carriers of HLA risk alleles, and 10 of 41 (24.4%) presented antineuronal antibodies. No significant correlation among HLA risk alleles, antineuronal antibodies and clinical features was found. In achalasia, no correlation exists among HLA alleles, antineuronal antibodies and clinical features. However, given the association between achalasia and HLA-DQ1, further research is needed to clarify the role of HLA antigens and antineuronal antibodies in this disease.