White blood cells 12 x 10/L is not normal, the normal white blood cell value is between (4-10) x 10/L. Therefore, the phenomenon of white blood cells 12 x 10/L indicates that there is a certain amount of inflammation in the body, which may be an infection of the upper respiratory tract, such as the phenomenon of a sore throat. Some people may have a urinary tract infection, with frequent and urgent urination, which may be a sign of urethritis, cystitis or pyelonephritis. Some people may have biliary tract infections, such as cholecystitis or cholangitis, which can lead to elevated white blood cells. Elevated white blood cells are commonly caused by bacterial infections, such as Staphylococcus aureus, Streptococcus, and Escherichia coli, all of which can lead to elevated white blood cells. Elevated white blood cells must pay attention to rest, can be combined with clinical symptoms for observation, and should be rechecked blood routine.