Association between HLA-A, B, C and DR antigens and clinical manifestations of Schistosoma haematobium in the bladder.

This study is a search for the genetic susceptibility of Egyptians to Schistosoma haematobium infestation with its various bladder complications, including cancer. 80 bilharzial patients, 20 with simple bilharzial bladder cystitis, 30 with bilharzial bladder lesions, and 30 with bilharzial bladder cancer, as well as 35 normal Egyptian controls were studied. All patients were typed for HLA-A, B, C and DR antigens using the microlymphocytotoxicity test. HLA-A9 and its split Aw24 antigens were found to be negatively associated with the disease. As for the antigens with positive associations, HLA-B7 was significantly increased in the simple bilharzial cystitis group. In the bilharzial bladder cancer group, HLA-B16 and Cw2 antigens had positive associations. These findings might support the genetic control of the disease or the presence of an immune response and/or immune suppression genes which are in linkage disequilibrium with these HLA antigens and they control the susceptibility and pathological sequences of the disease.