Suggest Treatment For High WBC And Swollen Inguinal Nodes

My daughter has a high wbc, low mpv. Symptoms include 3 weeks swollen inguinal nodes, and neck nodes,given flagyl at the time. std negative, yeast negative. Past days itchiness which has now gone away, rash, which also has gone away. She is a track athlete who trains constantly. All rbc normal, urinalysis normal, cxr normal, mono screen negative. Headaches at times, bouts of vomiting, muscle aches, and lethargy. Wondering ?