 [ Symptoms ] can weak liver cause shingles or herpes [ Disease ] an enlarged liver or spleen in someone with mononucleosis would prohibit them from playing contact or collision type sports everyone is recovery from mono is different so there are really no set rules for when to return to sports she would need to be individually cleared by her medical provider who would certify that a her liver enzymes have returned to normal b her liver and spleen are no longer enlarged and subject to injury and c she has recovered to the point of being able to handle the rigors of practice and games again