Red blood cell decreases are most likely due to anemia, and white blood cell increases may be due to inflammation.
Red blood cells are reduced because of various types of anemia, such as megaloblastic anemia or iron deficiency anemia, and aplastic anemia, and leukocytosis is most likely due to infection, especially bacterial infection, especially after surgery or tissue injury and in cases of malignancy and acute blood loss. If there are low red blood cells and high white blood cells at the same time, it is likely that the cause is after massive blood loss and leukemia, so it is necessary to go for a bone marrow test.
Red blood cell reduction leukocytosis often occurs in older patients with infections because of the underlying anemia, plus the stimulation of net bacterial infections this time of year.