Discordance between red cell and saliva Lewis phenotypes in patients with hydatid cysts

Patients with hydatid cysts and controls of the same Tunisian area were typed for ABO, Lewis and secretor phenotypes. A high incidence of red cell Le(a-b-) phenotype (34-37%) was found among hydatid cyst patients as compared to normal controls (13-16%). However, a large proportion of the patients with Le(a-b-) red cell phenotype had discordant red cell and saliva Lewis phenotypes since they secreted Lea and/or Leb antigens in saliva. In addition, 1 patient with Le(a+b-) red cell phenotype secreted Leb antigen in saliva. The remaining patients and all the controls had concordant red cell and saliva Lewis phenotypes. The discordant results between the phenotypes obtained in serum and saliva of hydatid cyst patients are probably the consequence of a decrease in the concentration of the circulating Lewis glycosphingolipids, secondary to the disease.