Helicobacter pylori infection in connective tissue disorders is associated with high levels of antibodies to mycobacterial hsp65 but not to human hsp60

Background. To investigate whether the Helicobacter pylori status influences levels of antibodies against mycobacterial heat shock protein (hsp) 65 and human hsp60 in systemic autoimmune diseases and to study the concentration of anti‐H. pylori antibodies in autoimmune patients and healthy controls. Materials and Methods. Antibodies against human heat‐shock protein hsp60, mycobacterial heat‐shock protein hsp65 were analyzed by ELISA. Anti‐Helicobacter antibodies were determined by enzyme immunoassay. Results. There was a markedly higher prevalence of H. pylori infection in undifferentiated connective tissue disease (82%) (n = 33) and systemic sclerosis (78%) (n = 55) but not in systemic lupus erythematosus (n = 49), polymyositis/dermatomyositis (n = 14), rheumatoid arthritis (n = 21) or primary Raynaud's syndrome (n = 26) compared with controls (59%) (n = 349). In autoimmune diseases H. pylori infection was associated with elevated levels of antihsp65 (p = .008) but not of antihsp60. Anti‐hsp65 levels were significantly higher in H. pylori‐infected (n = 129) than in uninfected patients (n = 69) (p = .0007). Conclusions. These findings indicate that in autoimmune diseases the infection with the H. pylori bacterium is associated with increased concentration of antimycobacterial hsp65.