What Causes Chronic Dry Cough, Tight Chest And Weakness While Treating Bronchitis?

My husband has been under treatment for three weeks for bronchitis. He has a chronic dry cough, tight chest and weakness. He has had a round of antibiotics, steroid injection, prescription cough syrup and albuteral nebulizer treatments every six hours. He has been home resting, or trying to rest, it is hard with his constant coughing. He is 58, usually in good health, non smoker and in a non smoking home. He did find out a few weeks ago he has stage three kidney disease - Unknown cause. He is a Gulf War Veteran. Today he is getting worse, meaning his chest is tight and it is hard to talk. No fever, last day of antibiotic. At a lost as to what to do since he has seen a doctor three twice in three weeks....normal labs,