My dad has been coughing for the past two months, and we've done all sorts of tests including one for TB, but everything came back negative. His CT scan showed he has a parenchymal cyst in the right lower lobe. I'm really worried and not sure what to do next. I've already suggested he uses a Rotacap twice a day, but is there something else we should be considering? What steps should we take moving forward?

Pulmonologist opinion is advised to the patient.