Spleen
Discuss splenic anatomy?
It is the largest single mass of lymphoid tissue in the body. It is related to the 9-11th ribs on the left side. The spleen is completely surrounded by the peritoneum except at the hilum. It is supplied by the splenic artery. The splenic artery branches supply spleen as end arteries. Thus, obstruction of one of them lead to splenic infarction. Spleen is drained by the splenic vein. Splenic vein joins with the superior mesenteric vein posterior to the neck of the pancreas to form the portal vein.
Splenic lymphatics drain into pancreaticosplenic nodes and then to coeliac nodes.
Spleen has a connective tissue capsule, which extends inward to divide the organ into lobules. The parenchyma of the spleen is termed the pulp of the spleen. There is red pulp and white pulp. Red pulp consists of large thin-walled blood vessels, the splenic sinusoids, interposed between reticular connective tissue, the splenic cords. Within the red pulp, there are small rounded white areas, the white pulp, formed by lymphoid tissue.
The spleen filters blood and removes pathogens and old erythrocytes. Like other lymphatic tissue, it produces lymphocytes.
Discuss splenectomy?
A splenectomy causes no noticeable ill effects in most patients. However, this may uncommonly cause overwhelming post-splenectomy infection, usually caused by the encapsulated bacteria Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitides.
Most infections after splenectomy could be avoided by
- Appropriate and timely immunisation- vaccination (against pneumococci, meningococci and H. Influenza) should be performed at least two weeks before splenectomy, or as soon as possible after emergency splenectomy
- Antibiotic prophylaxis- lifelong prophylaxis with oral phenoxymethylpenicillin (or erythromycin for people who are allergic to penicillin) is advised although efficacy remain unclear
- Prompt treatment of infection.
