Baby with Atopic Dermatitis

Patient: My son is 9 months old and since 3 months of age he is suffering from atopic dermatitis. This occurs on the cheeks, arms, behind the neck. we have been desperately looking for the cause but to no avail. The dermatitis causes redness on the cheeks and despite using emolient cream such as Avene Trixeria , Avene Cold Cream, Emovate and Cortisone creams it does not go away. we use only cotton clothes and have stopped using detergent to wash clothes.Blood test reveals that the baby is not allergic to cow milk protein, fish, pollens etc. Baby was only consuming breast milk and formula milk. we have stop the breast milk and but no resultPlease help us determine what is the cause. We noticed that the eczema flared up 1 week after the BCG Vaccine. Could that be the cause? or any allergy ?Baby is in good health and growing wellThanksVishal

Symptoms: Red Cheeks, Flakes when not moisturize, Itch