One of the reasons why patients with leukemia are more commonly hospitalized is thrombocytopenia. This means low platelets in the blood, and it is a common condition in any stage of leukemia. Many patients do not have any other symptoms and would only start bleeding all of a sudden.
In these cases, doctors need to rule out hemophilia, an inherited bleeding disorder that is more common than leukemia. They will also need to rule out infectious diseases that cause bleeding, especially if the patient has recently traveled to tropical countries. But in some cases, sudden and unexplained bleeding is caused by leukemia.