'Crackle' sound in lung has ex-smoker concerned

Dear Dr. Roach: I had pneumonia at the end of 2016, and in a follow-up with my primary-care doctor, he said I had some crackling in the right lower lobe of my lung. I had a chest X-ray in April, and nothing abnormal was found. I just had my six-month checkup, and the crackles still are there. Should he have ordered another chest X-ray? Do I need to be concerned that he's overlooking something? I am 69 years old and quit smoking 1985. — J.S. Answer: "Crackles" is a technical term for a lung sound that is heard with the stethoscope. It can represent fluid in the lungs, partial collapse of the lung, infection or one of a few other causes. Sometimes, after a bout of pneumonia, there could be some scarring, which might explain the crackles. However, in any person with a history of smoking, the risk for infection and tumor is much higher than in the general population. The risk of lung cancer starts going down after you quit, but it never goes down all the way to that of a person who never smoked, although it gets close after 15 years or so. Pneumonia can be caused by obstruction from a small lung tumor, one that might not show up on a chest X-ray. So if the abnormality on your exam persists, I think a follow-up chest X-ray or even a CT scan would be prudent. This is my opinion: There's no absolute right answer here, but I would sleep better at night with more reassurance. Email questions to ToYourGoodHealth@med.cornell.edu.