splenomegaly

introduction

craniocaudal measurement of 11-13 cm is frequently used as the upper limit of normal splenic size on imaging studies
2-5% of the population have a palpable spleen
patients with splenomegaly should be advised to avoid all contact sports as there is a risk of fatal splenic rupture
splenic rupture risk is higher in older patients as the splenic capsule thins with age

criteria include:
- anemia, leukopenia, thrombocytopenia, or combinations thereof, plus,
  - cellular bone marrow
  - splenomegaly
  - improvement after splenectomy
chronic, severe hypersplenism may occur in:
- hairy cell leukaemia
- Felty syndrome
- agnogenic myeloid metaplasia
- thalassemia major
- Gaucher disease
- haemodialysis splenomegaly
- splenic vein thrombosis

inflammatory response to infection or auto-immune conditions:
hypertrophy due to increased work of RBC destruction:
- hereditary spherocytosis
- thallasaemia major
- malaria
- hemoglobin SC disease
- NB. sickle cell disease results in a small, infarcted spleen rather than splenomegaly
venous congestion:
- congestive cardiac failure
- splenic vein thrombosis
- portal hypertension
- Banti disease
myeloproliferative:
- eg. chronic myeloid metaplasia
infiltrative:
- sarcoidosis
- amyloidosis
- Gaucher's disease
- some neoplasia / cancer / tumours
neoplastic:
- chronic lymphocytic leukemia
- lymphoma
- metastases
miscellaneous:
- traumatic haematoma
- cysts
- haemangioma
- splenic abscesses
- polycythaemia rubra vera