Splenectomy

... strain loses ground. If the antimicrobial pressure was constant (for example, a life-long antimicrobial treatment of a person who has undergone splenectomy), the mutant strain would be the dominant strain for the rest of the host organism's life - unless, of course, some new and even more beneficial ...

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... the immune cells within it function somewhat similarly to lymph nodes. Although a human can survive without the spleen, persons who have undergone splenectomy are more prone to certain infections, including dangerous septic infections by capsulated bacteria such as Streptococcus pneumoniae , Meningococcus ...

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