Dear Mr Nakul Das,
Your son is suffering from recurrent skin infections and respiratory infections. He is probably got many symptoms of atopy
or allergic tendencies but also could suffer from immunodeficiency
i.e problems with defective immunity. These are often genetic disorders. So your son Immunoglobulin levels IgG
, IgA and IgM, lymphocyte
subsets and PHA stimulation test need to be tested for. It would be great if you could also see a dietician to do skin prick testing for any food allergens.