Breathing problems with severe cough.

My niece who is 11 years has been having breathing problems with severe cough with sputum production every now and then. She uses nebulizers, pills, and syrups get relief, but then again gets these symptoms. Her cough is severe at night. She is hypothyroid and is on levothyroxine 75 mcg, which is under better control. She gets lethargic easily with any kind of activity. She had been to many pediatricians at different hospitals in Dubai, but nobody is able to diagnose the actual problem. Some have told that she might have mild asthma, but nobody referred her to pulmonologist. Can it be bronchiolitis or asthma, acute respiratory distress, infectious process or does she needs lab evaluation such as CBC, blood gas, PFTs. Please suggest and your help is appreciated. Can she directly consult pulmonologist.