Bronchiectasis

Hu Suping

Pulmonary Department

1st clinical college, Wuhan University

Definition an acquired disorder of the major bronchi and bronchioles characterized by permanent abnormal dilation and destruction of bronchial walls

the most common symptoms are chronic cough with large amounts of purulent sputum and/or recurrent hemoptysis

it involves chronic respiratory tract infection and an up-regulation of the host inflammatory response

Enhanced cellular and mediator responses bronchial mucosal biopsies reveal infiltration by neutrophils and T lymphocytes; expectorated sputum has increased concentrations of elastase and the chemoattractants IL-8, TNFa, and prostanoids

Pathological changes Cylindrical or tubular bronchiectasis: dilated airways alone, sometimes seen as a residual effect of pneumonia

Varicose bronchiectasis: focal constrictive areas along the dilated airways that result from defects in the bronchial wall

Saccular or cystic bronchiectasis: progressive dilatation of the airways, which end in large cysts, saccules, or grape-like clusters (the most severe form )

The lumen of the bronchus is dilated and thThe lumen of the bronchus is dilated and there is prominent chronic inflammation in tere is prominent chronic inflammation in the bronchial wallhe bronchial wall

Bronchiectasis can present in either of two forms — a local or focal obstructive process of a lobe or segment of a lung or a diffuse process involving much of both lungs and often accompanied by other sinopulmonary diseases, such as sinusitis and asthma

Pathophysiology and Etiology

Three types of focal airway obstruction

(1) luminal blockage by a foreign body, broncholith, or slowly growing benign tumor

(2) extrinsic narrowing due to enlarged lymph nodes (middle lobe syndrome)

(3) twisting or displacement of the airways after a lobar resection or chronic infection

Pathophysiology and Etiology

Infections

Childhood respiratory tract infections (pertussis or whooping cough)

Chronic infections( chronic lung abscess, TB)

Primary Ciliary Dyskinesia

an autosomal recessive syndrome, estimated frequency at birth is 1 in 15,000 to 1 in 40,000

half have Kartagener’s syndrome (bronchiectasis, sinusitis, and situs inversus viscerum)

Pathophysiology and Etiology

Immunodeficiency

humoral immunodeficiency syndromes (deficiencies of IgG, IgM, and IgA) at risk for recurrent suppurative sinopulmonary infections and bronchiectasis

immune globulin replacement reduces the frequency of infectious episodes and prevents further destruction of the airways

Clinical findings

Symptoms:

daily cough productive of mucopurulent phlegm

intermittent hemoptysis

recurrent lung infections

shortness of breath

Physical findings:

crackles, cyanosis

Chest radiography

High-resolution computed tomographic scanning (HRCT)

the defining modality for diagnosis of bronchiectasis

Specific abnormalities found on HRCT include

(1) dilatation of an airway lumen > 1.5 times as wide as a nearby vessel

(2) lack of tapering of an airway toward the periphery

(3) varicose constrictions along airways

(4) ballooned cysts at the end of a bronchus

Normal Lung and the Lung of a Patient with Bronchiectasis. Bronchiectasis is primarily in the lower lobe, which is the most common distribution. The saccular dilatations and grapelike clusters with pools of mucus are signs of severe bronchiectasis.

Normal lung Bronchiectasis

Bronchoscopy

an important diagnostic tool to examine for obstruction ( foreign body, tumor, structural deformity, or extrinsic compression from lymph nodes) and to help localize the bleeding ， to identify pathogen

Pulmonary function tests

obstructive impairment ( low FEV1 and/or low FEV1/FVC)

airway hyperresponsiveness ( 40% with a positive reversibility test result, and 30% to 69% with a positive bronchial provocative test result)

Diagnostic evaluation

(1) to confirm the diagnosis of bronchiectasis

(2) to identify potentially treatable underlying causes

(3) to provide functional assessment

Imaging of the chest is always necessary to confirm the diagnosis

Differential diagnosis Chronic bronchitis

Lung abscess

Pulmonary tuberculosis

Congenital bronchocele

Diffuse panbronchiolitis

Therapy Control infections： administration of antibiotics

Treatment of underlying conditions

Promotion of bronchial hygiene

Control of bronchial hemorrhage

Surgical therapy

Acute Exacerbations

An exacerbation: including four of the nine symptoms

change in sputum production; increased dyspnea; increased cough; fever (>38.0°C); increased wheezing; malaise, fatigue, lethargy, or decreased exercise tolerance; changes in chest sounds ； reduced pulmonary function; radiographic changes

Early antibiotic therapy: fluoroquinolone as levofloxacin or ciprofloxacin for at least 7 to 10 days

Sputum culture and sensitivity testing: who fail to respond to the initial antibiotic or who have repeated symptomatic attacks in a short interval

Bronchopulmonary HygienePostural drainage, chest physiotherapy, thinning and loosening of secretions, the administration of a bronchodilator and of inhaled corticosteroids –part of maintenance therapy and treatment for acute exacerbations

Hemoptysis

life-threatening hemoptysis: > 600 ml/ day

bronchoscopy or CT of the chest is warranted to help determine which lobe or side is bleeding

interventional radiology: selective bronchial arteries embolization

surgery may be required to resect an area suspected of bleeding

Surgery Removal of an obstructing tumor or residue of a foreign body

Elimination of the segments or lobes the most damaged and suspected of contributing to acute exacerbations, overwhelming viscous secretions, mucous impaction, and plugs

Elimination of areas that are subject to uncontrolled hemorrhage

Removal of damaged lung suspected of harboring problematic organisms such as multidrug-resistant M. tuberculosis or M. avium

Double-lung transplantation is now considered for patients with cystic fibrosis and respiratory failure (one year survival rate 75% and 48% at five years)