- Reactive thrombocytosis
- Most common cause of elevated platelet count in all age groups.
- It is generally caused by high levels of inflammatory cytokines (eg, IL-6), which prompt the liver to release thrombopoietin.
- Secondary to certain conditions, e.g.:
- Malignancy (e.g., CML)
- Splenectomy
- Chronic inflammation
- Autoimmune diseases: e.g., rheumatoid arthritis, celiac disease, connective tissue disorders
- Chronic infections: e.g., tuberculosis, syphilis