Thank you for your question.
I am Dr Saha, I shall try my best to help you.
The count can be low in infection.
As he had mild cough as the time of test, it is likely to be the cause.
It does not sound like leukemia.
However, as the symptoms got worse, he will need an examination by doctor again.
I think his hemoglobin level was not too low, so the doctor did not prescribe iron.
You can give him iron rich foods.
You can read this link on such foods.
I hope this information helps.
If there’s anything else I can do, please let me know.
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