Bile is a digestive fluid that emulsifies fat, but does not contain digestive enzymes. Bile-free stools are stools that do not contain bile or bile pigments. α1 antitrypsin deficiency liver disease occurs in newborns with hereditary α1 antitrypsin deficiency within 1 month of birth, resulting in slow weight gain, lethargy, irritability, and bile-free stools. Differential diagnosis of bile-free stools 1. obstruction of bile excretion Once a tumor or stone occurs in the extrahepatic biliary system, the bile duct is blocked and bile cannot be excreted smoothly, and obstructive jaundice occurs. When the biliary system is obstructed, the excretion of bile is hindered and bilirubin returns to the bloodstream causing jaundice, called obstructive jaundice. The site of obstruction may be intrahepatic or extrahepatic, and there are complete and incomplete obstructions. Common causes include capillary bile duct hepatitis, gallstone disease, hepatocellular carcinoma, bile duct cancer, pancreatic cancer, biliary ascariasis, etc. 2.Fecal pus and blood Pus and blood are mixed in the stool. Dysentery bacillus infection. In the epidemic season, there is a history of dysentery contact or a history of unclean diet, and symptoms such as fever, mucopurulent stool, and urgency. 3, malodorous, blistering white stool Patients with fecal nematode disease can excrete malodorous, blistering white stool, and even severe steatorrhea. Strongyloises stercoralis is a parthenogenetic parasite with alternating generations, with its autochthonous generation taking place on the ground and its parasitic generation taking place in the human body. The life history is more complex and the pathogenesis is long.