It is a concern that he is still having bronchial problems and colds etc.  It does make you wonder if the Doctor is right in his line of thinking because as anyone knows, exess corticosteroids affect the immune system.  Perhaps your baby does have CAH but like Chrsi states--it may be very mild.  As long as they wean him off the steroids in this case and do not quit them all at once, then his own adrenals will respond and make whatever cortisol they can.  Tests following that should give you a better picture because if 17 OHP is elevated after reductions at certain stages, this will give them an idea of how severe his CAH is.  

I would make sure that you are familiar with protocol around Adrenal Crisis and symptoms though and also make sure that you learn how to give cortisol shot and have a kit to perform such in the event that anything out of the ordinary crop up though.  It certainly cannot do any harm to play it safe and be prepared.  Especially before travelling out of the country.

Best of luck anyway and safe travelling.  I presume that you are travelling to see family or friends for christmas?  Have a good one anyway if we don;t see you post again before then.

Regards

Anne-Marie