Hepatitis B and chronic kidney disease: Bench to bedside

Table 3 Non-invasive methods used to assess liver fibrosis and their potential limitations in patients with chronic kidney disease

Method for liver disease severity	Interpretation about liver disease	Limitation(s) in patients with CKD
Pedal edema and/or ascites	It is a feature of decompensation and its presence indicate liver cirrhosis with significant portal hypertension	Pedal edema may be present due to fluid overload and hypoalbuminemia which is common in CKD patients
Low serum albumin level	Indicates poor synthetic function of the liver	Serum albumin may be low due to albuminuria or poor nutritional status
Liver biopsy	Gold standard for assessing liver fibrosis	High risk of bleeding in patients with CKD
APRI which require serum AST and Platelet counts	A widely-validated index whose value correlates well with significant liver fibrosis, and values > 2.0 strongly suggest the presence of cirrhosis	May underestimates liver fibrosis, because serum AST elevation is commonly attenuated in those with renal failure, particularly those on MHD
FIB-4 which is based on age, ALT, AST, and Platelet counts	A widely-validated index whose value correlates well with significant liver fibrosis, and values > 3.25 strongly suggest the presence of cirrhosis	May underestimates liver fibrosis, because serum elevation of ALT as well as AST is attenuated in those with renal failure, particularly those on MHD
Transient elastography	Measures liver stiffness, which correlates well with the stage of liver fibrosis, particularly in patients with HCV infection	Fluid overload adds to liver stiffness, leading to overestimation of the stage of liver fibrosis

APRI: Aspartate aminotransferase to platelet ratio index; AST: Aspartate aminotransferase; ALT: Alanine aminotransferase; FIB-4: Fibrosis-4 index; MHD: Maintenance hemodialysis; CKD: Chronic kidney disease.