My child is 9 years old and his recent blood work showed his alkaline phosphatase was 325 ,and his platelets were397. what could be the cause, what should i do and should i be as worried as i am? thanks for any help that you can give?

All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Talk to the doctor who ordered the tests. Having said that, alkaline phosphatase level is well within normal limits for a 9-year old, children have higher levels due to bone growth. Platelet count is not a concern, though and may be due low iron.