The main items of routine blood tests are: 1. hemoglobin and red blood cells, if the hemoglobin is low, it is indicative of various causes of anemia or some leukemia, red blood cells have increased or decreased, the increase is generally due to severe diarrhea, vomiting, the decrease is also due to some anemia and other causes. 2. white blood cell count, white blood cells are divided into neutrophils, eosinophils, etc., the increase in white blood cells is generally indicative of some bacterial infections. 3. The increase in leukocytes is generally indicative of bacterial infections, etc. 3, platelets, generally high and low platelets, may indicate some leukemia, low is generally indicative of reduced platelets, anemia and other causes.