[Subtypes of HBsAG in Morocco: general distribution in HBsAG carriers in Casablanca in terms of their clinical state. Relations with the markers of the HBe system]

Abstract

HBs Ag subtypes ad and ay were determined by counter-electrophoresis (CEP) among 301 persons from Casablanca found HBs Ag positive by CEP: 147 were asymptomatic HBs Ag carriers and 154 were patients with acute or chronic hepatitis. w and r determinants were investigated among 82 from them only. HBe antigen and antibody (AB) were investigated by gel double immunodiffusion among 294 persons. Into the whole population, the prevalence of ad and ay subtypes was respectively 20 and 80%. This distribution, intermediate between those reported in West Europe and West Africa, was in agreement with data previously reported by others in the Maghreb, but differing from these ones in the distribution of w and r determinants. ayr subtype was found dominant (39%) and adw rare (2.4%), the prevalences of adr and ayw being intermediate (25-30%). Among asymptomatic HBs carriers and patients only adr and ayr distribution differed: in the formers, adr was dominant and ayr rare and, in contrast, ayr was frequent and adr rare among patients. Elsewhere, some findings were in agreement with previously reported data by others, such as the frequent association of ad to chronic liver disease or long-term HBs Ag carriage, ay being rather associated to short-term carriage, the frequency of HBe Ab in ad subtype and the presence of ay among almost all HBs positive haemodialysed patients.