High total and direct bilirubin may be caused by congenital non-hemolytic jaundice with increased direct or indirect bilirubin, or by the presence of obstructive factors.
1. Congenital non-hemolytic jaundice with increased direct or indirect bilirubin: it may be due to congenital abnormality of bilirubin metabolism in hepatocytes, resulting in high total and direct bilirubin.
2. Existence of obstructive factors: direct bilirubin is synthesized by indirect bilirubin in the liver cells, and then synthesized into direct bilirubin and secreted into the bile ducts, and then enter the intestinal tract through bile outflow. When bile duct obstruction occurs, including stones or tumors, direct bilirubin cannot be excreted, and thus flows backward into the bloodstream, resulting in high total bilirubin and direct bilirubin.
Therefore, when both total bilirubin and direct bilirubin are high, liver and gallbladder ultrasound is needed to rule out organic lesions of the liver and gallbladder.