Child With Influenza Induced Rhabdomylolysis. Low WBC And Platelet Count. Due To The Flu?

My 5yr old son was admitted to hospital for influenza induced rhabdomyolysis as his discharged diagnosis. He had increased CK level that caused difficulty walking and standing on discharge he returned to 1100. The doctors were also concerned with his low white blood cell and platelet counts that were WBC 3.8 on admission then 3.7 then on discharge were 4.2. His platelets on admission were 133 and discharge they were 127. They stressed the importance of follow up for these labs. Could the flu have caused both of them to drop or may there be another underlying issue? His labs prior to the flu have been normal all the way back to 2011. He doesn t bruise easily, no weight loss He seemed to keep a cold pretty much all winter that is the only problem I could think of.