i noticed now you didn't check hbcag antigen, if it is positive he has a particular form of hbv which is called hbcab negative hbv, i don't know much aboutit because it is quite rare but it is cronic hbv so find a very good liver specialist
also check hbvdna as said above, hbvdna is always present on active cronic hbv and sometimes even after you clear hbsag naturally by immune system
ok we'll work on it.hmm what can you say about the result?can you say that he had the virus?
very strange, check hbvdna with very sentitive assay just to check if he has occult hbv or a mutated strain, and monitor alt/ast every 3 month for a long period
a biopsy can detect anything but i don't think it is the case, i'd do it only if alt/ast elevated and liver damage present
he might also make hbv vaccine to get hbsab reactive