Thanks for the query
with high WBC count
suggests infection. Normal platelet count
ranges from 150000-450000/cmm. Deviation from this range does not always signal any clinical problem. There are few condition in which platelet count can be raised, one of which is infection itself. As platelet as an acute phase reactant may raise in infection, it has to be correlated with other parameters and clinical features. In general count above 750000 needs workup to find out the cause or to rule out some diseases. In your case WBC count become normal (also child is afebrile after treatment) and platelet count is high.So I would suggest you to follow the platelet count after 1 week and if it is rising then consult your doc as further investigations may be needed then.
I hope this answers your query well
Wish you and your family good health