Thank you for your query.
Though you have mentioned the reticulocyte
count you have not mentioned the hemoglobin
level, total and differential counts.
The high reticulocyte count signifies that your son's body is producing a good quantity of red blood cells in response to the anemia
. As he is not feeding well, iron and vitamin supplements will have to be given to him.
Parenchymal infiltrates in the lung suggest an infection and the total and differential count would assist the doctor to start with the appropriate antibiotic, if required.
Kindly follow the doctor's advice and there is no reason why your son will not be alright.
I hope I have answered your query to your satisfaction.
Wishing your son an early recovery.
Rajiv K Khandelwal