一、概述血便是指来自消化道的血液经肛门排出,不论排出血量多少,只要大便中混有纯血、血水或血中带粘液和/或脓液,色鲜红、暗红或柏油样均属血便。血液来源还可来自口、鼻、咽及呼吸道,或来自外界。例如因食入动物的血、肝类、铁类药物等亦可出现黑便,这些情况统称为假性血便。 First, an overview Bloody stool refers to the blood from the digestive tract excretion of the anus, regardless of the amount of bleeding, as long as the stool mixed with pure blood, bloody or blood with mucus and / or pus, red, dark red or tarry-like Is a bloody stool. Blood can also come from the mouth, nose, pharynx and respiratory tract, or from the outside world. For example, due to ingestion of animal blood, liver, iron drugs can also occur black, these cases collectively referred to as pseudo bloody stool.