Can being obese cause an enlarged spleen? i was severely overweight, have fatty liver, but lft's are normal. so the liver seems to be functioning fine, wondering what could cause the spleen issue?

Yes: Non alcoholic fatty liver can cause portal hypertension which is a cause of spleen enlargement. Portal hypertension means that there is increased pressure and abnormal blood flow in portal vein system. Portal vein brings blood to the liver.

Many explanations: one most possible cause is portal hypertension, others could hypersplenism due to overdestructions of RBC