Routine blood tests are the most common laboratory tests that people have when they visit the hospital or have a physical examination. Recently, I had an impressive patient who came to my office with slightly increased white blood cells but significantly increased platelets, slight weakness, and no other symptoms, having already had a routine blood test done in another department. I gave her a careful physical examination and found that the enlarged spleen could be palpated under the left rib cage. Further blood smear examination revealed naïve cells and bone marrow examination determined that it was chronic myeloid leukemia in its chronic stage.
Blood disorders that can cause thrombocytosis include: primary thrombocytosis, true erythrocytosis, primary myelofibrosis, chronic myeloid leukemia, myelodysplastic syndrome 5q-, etc. Patients with thrombocytosis need to be seen by a hematologist for careful identification.