Causes of Bronchiectasis
Causes of Bronchiectasis vary, but all lead to inflammation and damage of the airway walls. The most common causes of bronchiectasis include severe lung infections, immune system problems, allergic reactions, congenital conditions, and obstruction of the airways. In many cases, especially in developing countries, tuberculosis is a major contributor.
One of the primary causes is past infection. Lung infections such as pneumonia, whooping cough, or tuberculosis can cause enough inflammation to damage the bronchial walls permanently. This damage leads to scarring and the development of abnormally widened airways where mucus collects.
Congenital conditions like cystic fibrosis are a well-known cause. In cystic fibrosis, thick, sticky mucus builds up in the lungs from birth, leading to chronic infection and bronchiectasis. While rare in South Africa, it is a major factor in high-income countries.
Immunodeficiency conditions — where the body has trouble fighting infections — also increase the risk. People with HIV, primary immunodeficiencies, or those on immune-suppressing treatments (such as chemotherapy or corticosteroids) may develop frequent lung infections that lead to bronchiectasis.
Allergic bronchopulmonary aspergillosis (ABPA) is another cause. This condition results from an allergic reaction to a common fungus called Aspergillus, and it causes airway inflammation and mucus plugging, eventually leading to airway dilation.
Causes of Bronchiectasis
Obstruction of the airways can also trigger bronchiectasis. Inhaled foreign bodies, tumours, or lymph node pressure can block airflow and create a breeding ground for infection. Over time, these infections can cause lasting damage.
In some cases, the exact cause remains unknown — this is referred to as idiopathic bronchiectasis.
Understanding the causes of bronchiectasis is essential for effective management. When the root cause is identified early, targeted treatment can reduce progression and prevent recurrent infections that worsen lung damage.
[Next: Symptoms of Bronchiectasis →]
