other conditions that act like mononucleosis? My daughter has been sick for a while know.  She experienced pain in her stomach and then started throwing up, she was not able to hold down even water.  Her white blood count was elevated and kytones in her urine.  @ days later she had a cat scan of her somach cause they thought could be appendix.  It wasn't but all liphnoids across the bottom of stomach were swollen.  Her white blood count went back to normal.  She still does not feel well.  She has a below normal temp is tired and feels drained has stopped throwing up though.  Her stomach is still tender to the touch and to move certain ways.  Her blood does say her body is under stress but not anything else.  They tested for mono but came back negative.  Doctor says he thinks its a virus and will not let her go to school for 2 or more weeks.  Any ideas what may be going on.  Very concerned.

Summarized question: Are there any other conditions that act like mononucleosis?