Brief Answer:
It can be bronchial astham

Detailed Answer:
Hello

Thanks for asking on this platform

Repeated episodes of wheeze with breathlessness which gets relieved by nebulisation can be due to bronchial asthma.
I have few queries
Does he has any breathing problem during night times also?
Is he on any inhalational medication?
Is there any family history of asthma or chronic lung disease?
Whether blood test for eosinophil count or serum IgE level (suggestive of allergy)done or not?

Based on the severity bronchial asthma can be controlled by inhalational medication.
Fibrosis changes can be there due to any old segmental collapse which is common in asthma.
I would also like to get a pulmonary function test done if not done previously to get a better idea about the disease.
I request you to attach the report and looking forward for your reply so that I better able to help you out.

Please let me know if you have any more query.
Regards

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