Histopathology of serial graft biopsies from liver transplant recipients.

Serial graft biopsies (n = 78) from 12 liver transplant recipients (followed clinically up to 47 months) were studied with the use of histology, histochemistry, immunostaining, and electron microscopy. Planned-protocol needle biopsy specimens were taken from the graft before removal from the donor, 1 hour after transplantation, on the eighth day, and at yearly intervals. Nonprotocol biopsies were taken when deterioration of the clinical condition made a decision on changes in the regimen necessary. The protocol biopsies provided a baseline for graft condition and diagnostic histopathologic features. In these biopsies signs of hyperacute rejection, chronic rejection, or the recipient's previous liver disease were not observed. Mild acute rejection was regularly present on the eighth day, possibly due to a lag phase in the effect of immunosuppression. The syndromes in the nonprotocol biopsies included "pure" parenchymal cholestasis, reversible acute rejection resembling chronic active hepatitis, viral infection, and acute bacterial cholangitis. Each of these syndromes correlated with a separate histopathologic entity. Therefore, these entities proved to be of diagnostic value. It is concluded that a graft biopsy may substantially add to the pathogenetic interpretation, differential diagnosis, and management of major graft syndromes in orthotopic liver transplant recipients.