Epidemiology of Helicobacter pylori in chronic haemodialysis patients using the new RIBA (TM) H-pylori SIA

Background. There are few data concerning the epidemiology of H. pylori in patients on chronic haemodialysis (HD) treatment. These surveys concerned s mall populations and were made with ELISA technique. However, ELISA-based a ssays do not differentiate between strains of H. pylori that are associated with ulcers. Recent literature reports that: formation of ulcers correlate s strongly with the expression of cytotoxin-associated protein (CagA) and v acuolating cytotoxin (VacA) of H. pylori. Methods. A novel serological test (RIBA(TM) H. pylori strip immunoblot assa y (SIA)) has been recently introduced, it uses the H. pylori lysate (Lys) a long with two additional purified recombinant antigens derived from CagA an d VacA of H. pylori. Aim. To study the epidemiology of H. pylori using RIBA (TM) H. pylori SIA among chronic HD patients and blood donors as a control group. In addition, the activity of H. pylori was analysed by immunoblot te chnique in a group of patients with documented ulcers and normal renal func tion. Results. The prevalence of antibody towards H. pylori among HD patients, bl ood donors, and patients with documented ulcers was 56% (127/228), 53% (84/ 158), and 100% (21/21) respectively; the difference was significant (P = 0. 0001). The frequency of anti-H. pylori-positive individuals was significant ly higher in patients with documented ulcers than HD patients and blood don ors, 21/21 (100%) vs 211/386 (55%), P = 0.0001. The frequency of antibody t o H. pylori in the HD population was significantly associated with race (P = 0.005); no relationship between anti-H. pylori antibody and numerous demo graphic, biochemical, and clinical features of patients was seen. The frequ ency of antibodies against virulent strains of H. pylori in HD patients and blood donors with H. pylori was 60% (76/127) and 61% (51/84) respectively; it was 86% (18/21) among individuals with documented ulcers. No significan t difference among these three groups occurred. Conclusions. The frequency of antibody towards H. pylori by RIBA(TM) H. pyl ori SIA was high both in HD patients and blood donors; patients with docume nted ulcers and normal renal function had significantly higher frequency of anti-H. pylori antibody. The anti-H. pylori antibody rate among HD patient s was strongly associated with race. The prevalence of antibody against vir ulent strains of H. pylori did not change among HD patients and control gro ups. Studies in large cohorts of HD patients with documented peptic nicer d isease are in progress.