A ct scan showed Pneumonia, could it be something else?

I have a friend, who has been complaining of a feeling of a lump in his throat for 3 years now. He describes it as the feeling you get when you get a pill stuck in your throat but the feeling is really low under the adams apple. He has gone to the doc twice already and had an ultrasound and blood work done. Nothing was found except a couple nodules around his thyroid, which the doctor swears are too little for him to feel. Then they decided to do a ct scan, they still didn't find anything in his throat but said he had pneumonia high in his left lung. Could Pneumonia look like something else on a ct scan? He has been diganosed with pneumonia 3 seperate times since this has been going on.