# Bronchiectasis

> Bronchiectasis for NEET-PG Pathology: permanent bronchial dilatation, cystic fibrosis and Kartagener causes, sputum layers and complications.

- Canonical URL: https://prepelephant.com/topics/neet-pg/pathology/bronchiectasis-pathology
- Exam / course: NEET-PG · Subject: Pathology
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-02
- Last updated: 2026-10-02
- How to cite: "Bronchiectasis", PrepElephant, https://prepelephant.com/topics/neet-pg/pathology/bronchiectasis-pathology

## Direct answer

Bronchiectasis is permanent dilatation of bronchi and bronchioles caused by necrotising or suppurative airway-wall inflammation, usually triggered by the combination of obstruction and infection. Dilated airways pool secretions that drain only with posture changes, producing the classic three-layered sputum, daily productive cough, halitosis, recurrent pneumonias, clubbing and localised crackles. Cystic fibrosis is the leading background in developed countries; post-infectious damage after measles, pertussis, adenovirus or tuberculosis, primary ciliary dyskinesia and immunodeficiency account for most of the rest.

## What you must remember

- **Definition:** abnormal, irreversible dilatation of airways with destruction of smooth muscle and elastic tissue from inflammation, extending towards the pleura on imaging.
- **Causes to recite:** cystic fibrosis (commonest in the West), post-infectious (measles, pertussis, adenovirus, tuberculosis, staphylococcal pneumonia), obstruction by tumour or foreign body, primary ciliary dyskinesia, hypogammaglobulinaemia, and allergic bronchopulmonary aspergillosis.
- **Kartagener syndrome:** the triad of situs inversus, sinusitis and bronchiectasis, from dynein arm defects of respiratory cilia; male infertility from immotile sperm completes the picture.
- **Morphology:** dilated airways forming sacculations (saccular worst, cylindrical mildest, varicose intermediate), wall fibrosis with lymphoid aggregates, and luminal suppuration.
- **Clinical:** large-volume, foul, three-layered sputum (mucus, saliva, pus), clubbing, localised coarse crackles that shift with position, and episodic haemoptysis, sometimes massive.
- **Imaging:** high-resolution computed tomography is diagnostic, showing signet-ring bronchi, tram-tracking and airway dilatation not tapering peripherally — "finger-in-glove" plugging when impacted.
- **Complications:** pneumonia, lung abscess, empyema, massive haemoptysis requiring embolisation, cor pulmonale, metastatic brain abscess and secondary amyloidosis in longstanding disease.

## Common confusion

Bronchiectasis is not simple chronic bronchitis: the airway is structurally destroyed and dilated rather than merely inflamed, with clubbing and copious purulent sputum favouring bronchiectasis. Dry or "bronchitis-free" bronchiectasis, presenting mainly with recurrent haemoptysis in upper-lobe tuberculosis, contrasts with the wet classic form. Remember that in Kartagener the root defect is ciliary immotility — situs inversus is randomised organogenesis — while in cystic fibrosis the root defect is a chloride channel, with bronchiectasis the end-result of thick, sticky mucus.

## Exam-focused takeaway

Vignettes describe an adult with childhood measles or tuberculosis now producing cupfuls of layered sputum with clubbing, or a child with dextrocardia, sinusitis and recurrent pneumonia (Kartagener). Questions ask for the diagnostic modality, the cause of three-layered sputum, the triad of Kartagener, or the distant complications — brain abscess and amyloidosis — that separate bronchiectasis from COPD. Answer with airway destruction plus suppuration.

## Frequently asked questions

### What defines bronchiectasis pathologically?

Permanent dilatation of bronchi and bronchioles with destruction of muscular and elastic wall elements following necrotising inflammation.

### What is Kartagener syndrome?

The triad of situs inversus, paranasal sinusitis and bronchiectasis caused by defective dynein arms of cilia, with associated male infertility.

### Why is sputum three-layered in bronchiectasis?

Settled sputum separates into a top frothy mucus layer, a middle clear saliva layer and a bottom dense purulent layer, reflecting pooled suppuration in dilated airways.

### Which investigation diagnoses bronchiectasis?

High-resolution computed tomography of the chest, showing non-tapering, signet-ring airways; plain radiographs are insensitive.

### Name the distant complications of bronchiectasis.

Metastatic (brain) abscess and secondary amyloidosis from chronic suppuration, besides pneumonia, massive haemoptysis and cor pulmonale.