If a spleen is damaged the extent you have to be on penicillin for the rest of your life, what has actually happened to it?

Loss of function: If your doctors are concerned enough to put you on life long antibiotics because of splenic dysfunction, then something relatively catastrophic happened to it. Was it splenic rupture (injury), infarction (blood clot), surgery or other cause the doc might have talked about? The spleen is very important for fighting infection -and is effectively a 'trap' for bacteria that might be circulating.