RESUMO
Hepatorenal syndrome (HRS) was originally defined as a renal dysfunction caused by a decreased renal perfusion due to hemodynamic disturbances in the arterial circulation and an excessive activity of endogenous vasoactive systems in the course of cirrhosis. Considering the latest research, this syndrome may have a more complex pathomechanism. Equally often as in cirrhosis, HRS develops after orthotopic liver transplantation (OLTx) and worsens the prognosis significantly increasing mortality rates in this patient population. The prevalence of renal complications after OLTx and their negative prognostic impact on the survival of both the graft and the recipient prompted the authors of this work to analyze in detail 2 cases of HRS after OLTx to indicate the multiplicity of factors contributing to the pathophysiology of this syndrome. Attention was paid to risk factors for HRS found in the anamnesis before OLTx, especially a pre-existing renal dysfunction. In both cases early post-OLTx complications associated with the transplantation procedure were described: destabilization of the circulatory system, transfusions of blood products, prolonged stay at an intensive care unit, and necessity of introducing continuous renal replacement therapy. In the later period after the OLTx, infections (bacterial, fungal, viral) and drug nephrotoxicity, including the activity of immunosuppressants (tacrolimus), contributed primarily to the renal function impairment.