Can asthma[ if not treated properly] also sometimes cause bronchiectasis. i ve this condition but am unclear as to why?

Possibly: More often, bronchiectasis is the end product of bad infections or inflammation which destroy the structure of the large tubes in the breathing system. Potential causes include tuberculosis, cystic fibrosis, immunodeficiencies, or alpha-1 antitrypsin deficiency. You should speak to your provider for more information on the proper testing.

Yes: Especially if you have repeated infections. There is a less common cause of asthma called allergic bronchopulmonary aspergillosis that can result in bronchiectasis as well.