Brief Answer:
The cause for folded lung requires to be treated.

Detailed Answer:
Hi XXXX,
Thanks for writing in to us.

I have read through your query in detail.
I suppose you are talking about the X ray chest or CT scan chest findings of your son that shows the major fissure in left lung shifted upwards with the possibility of a folded lung. It is also called as round atelctasis.

There can be many causes for a folded lung which includes the following:
It can be seen association with:
(i) Asbestos lung exposure most commonly
(ii) Congestive heart failure
(iii) Pulmonary infarction
(iv) Parapneumonic effusion

In itself, folded lung is a benign condition which is the outcome of any of the conditions listed above. It is important to treat the cause for the folded lung if present. Depending on the causes, this may persist or improve. This is not a concern by itself.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

---