Bronchiectasis

Bronchiectasis
A condition characterized by chronic permanent dilation & destruction of bronchi due to destructive changes in the elastic and muscular layers of bronchial walls.


The common thread in the pathogenesis of bronchiectasis consists of difficulty clearing secretions & recurrent infections with a “vicious circle” of infection and inflammation resulting in airway injury and remodelling.

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1. Bronchiectasis By: Karunesh Kumar

2. Bronchiectasis A condition characterized by chronic permanent dilation & destruction of bronchi due to destructive changes in the elastic and muscular layers of bronchial walls. May be diffuse or localized resulting in impairment of the drainage of bronchial secretions .

3. Aetiology Congenital Cystic Fibrosis ( Most common cause ) Primary hypogammaglobinemia leading to recurrent infection Ciliary dysfunction syndrome Acquired (In children) Secondary to pneumonia which occurs often as complication of whooping cough and measles

4. Bronchiectasis can also be congenital, as in: Williams-Campbell syndrome , in which there is an absence of annular bronchial cartilage. Marnier-Kuhn syndrome (congenital tracheobronchomegaly ), in which there is a connective tissue disorder.

5. Other disease entities associated with bronchiectasis are: Right middle lobe syndrome (chronic extrinsic compression of right middle lobe bronchus by hilar lymph nodes) Yellow nail syndrome (pleural effusion, lymphedema, discoloured nails).

6. Pathogenesis The common thread in the pathogenesis of bronchiectasis consists of difficulty clearing secretions & recurrent infections with a “vicious circle” of infection and inflammation resulting in airway injury and remodelling .

7. 3 mechanisms: 1. Obstruction - can occur because of tumour, foreign body, impacted mucus due to poor muco-ciliary clearance, external compression, bronchial webs, and atresia . 2. Infections d/t Bordetella pertusis , measles, rubella , adenovirus, and mycobacterium tuberculosis induce chronic inflammation.

8. 3. Chronic inflammation contributes to the mechanism by which obstruction leads to bronchiectasis. Inflammatory mediators such as neutrophil elastase , interleukin-6, interleukin-8, and Tumor necrosis factor-α (TNF-α) have been found to be elevated in the airways of patients with bronchiectasis

9. Pathological forms of Bronchiectasis Cylindrical bronchiectasis- bronchial outlines are regular, but there’s diffuse dilatation of the bronchial unit. Bronchial lumen ends abruptly because of mucous plugging. Tramline appearance on CT scan. Varicose bronchiectasis- degree of dilatation is greater, local constrictions cause irregularity of outline resembling that of varicose veins. Beaded contour on CT scan.

10. Cont.. Saccular (Cystic) bronchiectasis- bronchial dilatation progresses and results in ballooning of bronchi that end in fluid or mucous filled sacs. Most severe form of Bronchiectasis . Prebronchiectasis - chronic or recurrent endobronchial infection with non specific HRCT changes – may be reversible.

11. Clinical Features Cough: Chronic productive cough usually worse in the morning & often brought on by change in posture. Cough occurs due to accumulation of pus in dilated bronchi. Sputum: copious & purulent Fever Hemoptysis Anorexia and poor weight gain may occur as time passes. Crackles localized to the affected area Wheezing as well as digital clubbing may also occur

12. Diagnosis Thin-section HRCT scanning- is the gold standard, because it has excellent sensitivity and specificity. CT - provides further information on disease location, presence of mediastinal lesions, and the extent of segmental involvement . Chest X-ray- increase in size and loss of definition of bronchovascular markings, crowding of bronchi, and loss of lung volume. Severe case: Honeycombing Sputum culture.

13. Treatment Aims at decreasing airway obstruction and controlling infection . Postural drainage and control Infection. 2 to 4 wk of parenteral antibiotics is often necessary to manage acute exacerbations adequately. Amoxicillin/ Clavulanic acid (22.5mg/kg/dose twice daily) has been successful at treating the exacerbations. Long-term prophylactic oral (macrolide) or nebulized antibiotics (e.g ., tobramycin , colistin , aztreonam ) may be beneficial. Airway hydration (inhaled hypertonic saline or mannitol ) also improves quality of life in adults with bronchiectasis. Any underlying disorder ( immunodeficiency, aspiration ) that may be contributing must be addressed.

14. Prognosis Children with bronchiectasis often suffer from recurrent pulmonary illnesses.

15. Reference Kliegman , R., Stanton, B., St. Geme , J., Schor , N. and Behrman, R. ( n.d. ). Nelson textbook of pediatrics . 20th ed. Short textbook of Medical Diagnosis and Management by Mohammad Inam Danish