Biliary Atresia Is Associated With Hypertension

Well Preserved Renal Function in Children With Untreated Chronic Liver Disease

OBJECTIVES

On the basis of studies with hepatorenal syndrome, it is widely regarded that renal function is impacted in chronic liver disease (CLD). Therefore, we investigated renal function in children with CLD.

METHODS

In a retrospective study of 277 children with CLD, renal function was investigated as glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), measured as clearance of inulin and para-amino hippuric acid or clearance of iohexol. The data were analyzed with regard to different subgroups of liver disease and to the grade of damage.

RESULTS

Hyperfiltration (>+2 SD of controls) was found in the subgroups of progressive familial intrahepatic cholestasis (44%), glycogenosis (75%), and acute fulminant liver failure (60%). Patients with biliary atresia, most other patients with metabolic disease and intrahepatic cholestasis, and those with vascular anomalies and cryptogenic cirrhosis had normal renal function. Decreased renal function was found in patients with Alagille's syndrome (64% < -2 SD). Increased GFR and ERPF was found in patients with elevated transaminases, low prothrombin level, high bile acid concentration, and high aspartate-aminotransferase-to-platelet ratio.

CONCLUSIONS

Most children with CLD had surprisingly well preserved renal function and certain groups had even hyperfiltration. The finding that children with decompensated liver disease and ongoing liver failure had stable kidney function suggests that no prognostic markers of threatening hepatorenal syndrome were at hand. Moreover, estimation of GFR based on serum creatinine fails to reveal hyperfiltration.

Evaluation of renal functions in pediatric liver transplantation

AKI is an important complication after LT. As our LT series contains a quite high number of children with ALF unlike published studies, we aimed to determine pre-LT and long-term renal functions in children both with ALF and with CLD. Demographic and disease-related data of 134 transplanted children were evaluated retrospectively. Pre-LT and follow-up GFR and pediatric RIFLE scores were determined. Mean pre-LT GFR was not dependent on the disease presentation or severity of chronic disease. While there was an initial decline until first week of post-LT in CLD children, an increase was observed in ALF. Neither mean GFR nor the pRIFLE on follow-up was different with respect to the type of LT or disease presentation. Mean GFR at first and sixth months were lower in children on cyclosporine compared to tacrolimus (p = 0.001 and p = 0.002, respectively). In conclusion, GFR-time curve was different in children with or without ALF. Type of LT, and severity of the CLD were not risk factors for CKD in any time, but younger age at LT, CLD, and cyclosporine usage were at sixth months of follow-up.

The Kidney in Pediatric Liver Disease

There is an intricate relationship between the liver and the kidney, with renal physiology and function intimately involved in many primary disorders of pediatric liver disease. The hemodynamic changes of progressive cirrhosis affect and are directly affected by changes in renal blood flow and renal handling of sodium and free water excretion. Resulting complications of worsening ascites, hyponatremia, and acute kidney injury frequently complicate the care of children with advanced liver disease and contribute significant morbidity and mortality. While liver transplantation may restore hemodynamic stability, nearly 40% of pediatric liver transplant recipients develop chronic kidney disease post-transplant and approximately 25% are left with clinical hypertension. This review seeks to provide a basic understanding of this relationship to enable the provision of optimal care to children with liver disease.