[Evaluation of kidney function in patients before and after orthotopic liver transplantation]

Subjects before and after orthotopic transplantation of the liver develop frequently renal disorders. Evaluation of the renal function based on the serum creatinine concentration or its clearance is difficult in these cases because the concurrent hyperbilirubinaemia usually interferes with the method used for creatinine assessment (based on Jaffé's positive chromogen) and gives incorrect lower values. In the submitted work the authors investigated the development of the serum creatinine concentration and serum bilirubin concentration in 50 subjects before and one year after transplantation of the liver. The findings suggest that although under conditions of hyperbilirubinaemia creatinine cannot be evaluated by the usual methods, it is possible to obtain clinically useful information by investigating the trend of the relationship of creatinine and bilirubin. A decline of bilirubin is associated with a rise of creatinine which need not imply a decline of renal function, as long as creatinine does not exceed the upper range of normal values. Conversely the rise of bilirubin associated with a drop of creatinine need not imply improved renal function. In the investigated group one year after transplantation of the liver an impaired renal function (creatinine > 105 mumol/l) at a normal bilirubin level (< 21 mumol/l) in 17 (49%) subjects was found. In 7 (64%) subjects with hyperbilirubinaemia the creatinine value was within a normal range--this finding however does not rule out reduced renal function. Evaluation of renal function with concurrent hyperbilirubinaemia calls for more accurate methods. With regard to the mentioned findings however investigation of the trend creatinine/bilirubin makes it possible to evaluate the dynamics of changes of renal function.