The spleen, similar in structure to a large lymph node, acts as a blood filter. Current knowledge of its purpose includes the destruction of old red blood cells and platelets, and the detection and fight against certain bacteria. It's also known to create new blood cells. The spleen is enlarged in a variety of conditions such as malaria, mononucleosis and most commonly in "cancers" of the lymphatics, such as lymphomas or the leukemia.
It is removed under the following circumstances:
- When it becomes very large such that it becomes destructive to platelets/red cells
- For diagnosing certain lymphomas
- When platelets are destroyed in the spleen as a result of an auto-immune process (see also idiopathic thrombocytopenic purpura)
- When the spleen bleeds following physical trauma
- Following spontaneous rupture
- For long-term treatment of congenital erythropoietic porphyria (CEP) if severe hemolytic anemia develops
The classical cause of traumatic damage to the spleen is a blow to the abdomen during a sporting event. In cases where the spleen is enlarged due to illness (mononucleosis), the smallest things such as leaning over a counter or straining at stool can cause it to rupture.
Vaccination for pneumococcus, H. influenza and meningococcus should be given pre-operatively if possible. In general, spleens are removed by laparoscopy (minimal access surgery) when the spleen is not too large and when the procedure is elective. It is performed by open surgery for trauma or large spleens. Both methods are major surgeries, and are performed under general anesthesia. The spleen is located and disconnected from its arteries. The ligaments holding the spleen in place are dissected and the spleen is removed. When indicated a drain is left in place and the incision(s) is closed. If necessary, tissue samples are sent to a laboratory for analysis.
Because splenectomy causes an increased risk of overwhelming sepsis due to encapsulated organisms (such as S. pneumoniae and Haemophilus influenzae) the patient should be immunized, if possible, prior to removal of the spleen; see asplenia. An increase in blood leukocytes can occur following a splenectomy. Failure to do so later puts the patient at risk of overwhelming post-splenectomy infection (OPSI), a potentially rapidly fatal septicaemia. These bacteria often cause a sore throat under normal circumstances but after splenectomy, when infecting bacteria cannot be adequately opsonized, the infection becomes more severe.
Following splenectomy, the platelet count may rise to high levels in blood leading to an increased risk of clot formation and death.
- Frye R. (2006-03-02). "Porphyria, Cutaneous". eMedicine. Text " accessdate 2006-03-28" ignored (help)
- "Guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen. Working Party of the British Committee for Standards in Haematology Clinical Haematology Task Force". BMJ. 312 (7028): 430–4. 1996. PMID 8601117 Full text.
- J M Davies; et al. (2001-06-02). "The Prevention And Treatment Of Infection In Patients With An Absent Or Dysfunctional Spleen - British Committee for Standards in Haematology Guideline up-date". BMJ. Full text.