There are traditionally four components that make up hypersplenism:
- Large spleen (obviously!)
- Cytopenia(s) (at least one of: anaemia, thrombocytopenia, leukopenia)
- Normal bone marrow (which should therefore be hyperplastic in compensation for the cytopenia(s))
- Correction of the cytopenias following splenectomy
Obviously, you don't just whip out the spleen to see if things improve; you use the other criteria as well as a fair dollop of clinical acumen before embarking on any butchery. Patients tend not to like unnecessary operations.