Bronchiectasis

Bronchiectasis refers to an anatomical lesion characterized by dilatation of the bronchi.

In this condition, there is inflammatory destruction of the bronchial and peri-bronchial tissue, which allows for the accumulation of exudative material within the bronchi.

This accumulation leads to distension and, in some instances, near permanent dilatation of the bronchi.

Bronchiectasis can be classified into three anatomic cum pathological types:

1. Cylindrical: The dilatation affects the entire bronchial unit and the bronchial outlines are regular with a peripheral abrupt cut-off resembling a “pruned tree”.
   • Frequently associated with pneumonia and is the potentially reversible type.
2. Varicose bronchiectasis: The affected bronchial unit has an irregular outline with areas of dilatation and constrictions (like a varicose vein), with or without areas of saccular distension.
3. Cystic or saccular bronchiectasis: The presence of balloon-shaped distension or sacs containing fluid or mucus in the affected bronchial unit. This is the most severe variant.

Congenital or Inherited Defects

1. Maldevelopment of the bronchi:
   • Connective tissue developmental failure of congenital tracheobronchomegaly (Mounier-Khun syndrome)
   • Absence of annular part of the bronchial cartilage (Williams-Campbell syndrome)
   • Congenital tracheobronchomalacia
   • Marfan’s syndrome
2. Congenital lung cysts or sequestration
3. Primary ciliary dyskinesia (as may be seen in Kartagener’s syndrome)
4. Inherited/genetic defects with or without anatomic anomalies like racial susceptibility to ciliary dyskinesia (e.g. in Aborigines, Polynesians & Eskimos)
5. Cystic fibrosis
6. Alpha-1 antitrypsin deficiency
7. Yellow-nail syndrome (discoloured nail, lymphoedema, pleural effusion)
8. Immunodeficiency states (e.g. IgA deficiency and hypogammaglobulinaemia)

Acquired

Post-Infectious:

1. Pneumonia {especially due to necrotizing bacteria e.g. S. aureus, Klebsiella species and viruses (especially adenovirus)}
2. Bronchiolitis obliterans (of adenovirus aetiology), with or without unilateral hyper lucent lung syndrome (Swyer-James or McLeod syndrome)
3. Primary tuberculosis
4. Measles
5. Pertussis

Others/Miscellaneous

1. Foreign body aspiration
2. Right middle lobe syndrome (with or without bronchial asthma)
3. Dyscollagenoses or autoimmune states like rheumatoid arthritis, systemic lupus erythematosus (SLE), Sjögren syndrome and relapsing polychondritis
4. Inflammatory bowel disease

• Comprise difficulty in clearing secretions associated with sustained obstruction (of the major or peripheral bronchi), a consequent retention of bronchial secretions and recurrent infections.
• Bronchial wall weakness occurs from damage to the muscular and elastic tissue components, replaced by fibrous tissues, and loss of normal bronchial flexibility.
• Lastly, there is dilatation of the affected bronchial segment and a continuing or recurrent infection in the accumulated secretions.
• Consequently, the attendant chronic inflammation at the affected segment perpetuates the bronchiectatic process.

• In children, severe pneumonia, pertussis, or measles may precede an acute onset of symptoms in non-tuberculosis associated cases. For these preceding infectious causes, cough, dyspnea, wheezing, and fever are common.
• The earliest clinical indicator is a poor resolution or prolongation of the initial symptoms, supported by persistent radiographic signs and atelectasis features.
• A history of choking followed by acute breathlessness may suggest a previous foreign body aspiration.
• Recurrent sinus and/or middle ear infections along with recurrent pneumonia may indicate possible ciliary dyskinesia.
• On average, the disease onset age is 5 years, though those with antecedent adenovirus infections tend to be much younger (often <3 years).
• Chronic persistent or recurrent cough (>28 days), usually worse in the morning, and in older children, accompanied by a relatively copious amount of foul-smelling sputum.
• Less commonly, there might be haemoptysis resulting from bronchial mucosal erosion in the severe saccular type.
• Some affected children may seem well, but they might experience general symptoms like:
  • Poor weight gain (or weight loss)
  • Poor appetite
  • Dyspnea upon exertion, particularly in cases of severe, long-standing disease.

Physical Findings of Bronchiectasis

• The physical findings of bronchiectasis can range from minimal or no general and chest findings to signs suggestive of chronic malnutrition, manifestations of the underlying condition such as tuberculosis, and symptoms linked with acute episodes of bronchitis or pneumonia.
• Even in severe cases, there are no distinctive signs pathognomonic of bronchiectasis.
• In cases with symptoms, the child may exhibit underweight status.
• Digital clubbing may be present in approximately 10-50% of cases:
• The presence of clubbing does not necessarily correlate with the extent and severity of pulmonary lesions.
• Bronchiectasis-related clubbing can often be reversed with effective medical or surgical treatment.
• Foul-smelling breath (halitosis) is also a common feature.
• Fever, dyspnea, and rapid breathing (tachypnea) are prevalent during acute exacerbations of pulmonary infections.
• In the early stages of mild/moderate disease, pulmonary findings include:
• Persistent crepitations
• Diminished breath sounds
• ± Dull percussion notes (even after several weeks or months) that are localized to a specific chest area despite presumed adequate treatment for presumed pneumonia.
• Intermittent wheezing or rhonchi may be audible, indicating potential lower airway obstruction.
• A continuous pleural rub (suggesting recurrent pleurisy) may also be heard over the affected area.
• Tachycardia is common during acute exacerbations.
• Dextrocardia may serve as an important indicator of underlying ciliary dyskinesia.

The natural course is characterized by:

• Intermittent improvements and relapses
• Generally, there is a tendency for sustained asymptomatic periods as the child approaches adolescence.

The most common complications include:

• Atelectasis
• Haemoptysis
• Lung abscesses
• Cerebral abscesses
• Chest deformities
• Empyema
• Broncho pleural fistulae
• Pneumothorax
• Severe pneumonia
• Emphysema

In the case of long-standing cases, complications can include heart failure or fatal cor pulmonale, as well as amyloidosis.

Radio-Imaging Investigations

Chest X-ray (postero-anterior & lateral):

• May appear normal
• Show increased bronchovascular markings over the affected area(s)
• Basal atelectasis (manifesting as a dense triangular shadow adjacent to the right cardiac border)
• Fibrosis
• Multiple small fluid levels
• Rarely, rings with clear centers within an area of fibrosis
• Polygonal translucencies surrounded by dense linear shadows (honeycomb appearance)

Thin-section, high-resolution CT scans (the current gold standard):

• Enables accurate anatomic diagnosis
• Provides useful information about the affected site(s)
• Identifies the presence of mediastinal lesions
• With radio-labelled aerosol inhalation, CT can identify the morphology or pathological variant of the lesion

Bronchoscopy

Involves the use of a fibreoptic bronchoscope to:

• Visualize the trachea-bronchial airway, aiming to exclude the presence of a foreign body, stricture, or tumor
• May be necessary before a bronchogram
• May also serve as the sole method for obtaining uncontaminated bronchial secretions for microbiological studies

Microbiological

Cultures of sputum or, when available, materials obtained at bronchoscopy:

• Usually show a wide spectrum of potential pathogens and frequently a mixed flora, which might not be directly related to the disease
• Organisms include common aerobes such as Staphylococcus aureus and Streptococcus species (including S. pneumoniae), Haemophilus influenzae, as well as anaerobic agents like fusiform bacilli
• Others include acid and alcohol-fast bacilli (AAFB), Mycoplasma pneumoniae, and perhaps viral cultures along with complement fixation serology for adenoviruses
• A tuberculin skin (Mantoux) test is typically required when clinical and radiographic features suggest a tuberculous etiology

Pulmonary Function Tests (PFT)

• These parameters may exhibit an obstructive pattern in the early stages of the disease.
• Mixed obstructive and restrictive patterns are common, but severely impaired diffusion values (such as carbon monoxide transfer factor) typically arise only in advanced disease.
• PFT parameters are valuable for determining the necessity of surgical intervention and play a role in post-operative follow-up.

Other Investigations

• Immunological Parameters:

Serum immunoglobulin levels (IgG, IgE, and IgA) are necessary to rule out specific immunoglobulin deficiencies and hypogammaglobulinemia.

• Alpha-1-Antitrypsin Electrophoresis
• Electron Microscopy of Epithelial Cells (from Nasal or Bronchial Biopsy Specimens):

Airway mucosal biopsy and subsequent electron microscopy are valuable for detecting ciliary abnormalities. This is particularly relevant in cases of ciliary dyskinesia or the severe variant of Kartagener syndrome.

The goals of the initial medical measures include:

1. Control of ongoing respiratory infections (such as sinusitis, bronchitis, pneumonia, or pleurisy)
2. Relief of atelectasis
3. Amelioration of associated airway obstruction

There are two treatment modalities: medical and surgical.

Medical Therapy

The major elements of medical therapy in bronchiectasis include:

• Antimicrobial therapy
• Drainage of retained secretions & chest physiotherapy
• Amelioration of associated lung collapse
• General supportive therapy

Antimicrobial Therapy

• A 2-4 week course of antimicrobial therapy is often necessary to control acute flares of pulmonary infections and sinusitis.
• Parenteral route is preferred, at least for the initial 7-14 days.
• The choice of antimicrobial(s) depends on the nature and sensitivity of the pathogens identified from sputum or bronchoscopic washings. Empirical choice should cover common pathogens like Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae.
• Antituberculous medications, according to the current national antituberculous guidelines, are required in those with TB-associated lesions.

Drainage of Retained Secretions & Chest Physiotherapy

These are achieved through:

• Frequent postural drainage exercises (initially and during acute pulmonary exacerbations) and, when available, aided by bronchoscopic evaluation.
• The effectiveness of drainage exercises is enhanced with occasional use of bronchodilators, warm moist inhalations, and positive pressure breathing.
• Routine chest physiotherapy, using selected physical exercises, is beneficial in preventing frequent exacerbations and maintaining health.

Amelioration of Associated Lung Collapse

• Postural drainage usually alleviates segmental or lobar atelectasis in most patients, but
• Fibreoptic bronchoscopy is required for patients unresponsive to postural drainage maneuvers.
• Bronchoscopy is also necessary for removing a bronchial foreign body, or identifying other potentially correctable causes of impaired bronchial drainage such as strictures, or rarely in children, tumors.

General Supportive Therapy

• Nutritional support
• Rational use of antipyretics/analgesics (for symptom control of fever and pleuritic pain during acute flare-ups)
• Management of underlying specific immunodeficiency states like hypogammaglobulinemia, possibly with judicious use of chemoprophylaxis, is an equally beneficial supportive measure.

Surgical Therapy

The indications for initiating surgical treatment include:

• Extensive or recurrent haemoptysis
• Failure of antimicrobial therapy to control localized infection with consequent frequent flare-ups of bronchitis and pneumonia
• Development of hypertrophic pulmonary osteoarthropathy
• Failure to thrive
• Persistent or recurrent bronchial obstruction
• Presence of a foreign body that is irretrievable with bronchoscopic maneuvers
• Advanced localized disease of a saccular or varicose (fusiform) type

Regardless of the indications for surgery, the elective procedure is best delayed until the child is 8 – 10 years old and if possible 10 – 15 years.

The options of surgical intervention include:

• The resection of the affected segment or lobe
• Where facilities are available, lung transplantation
• Bronchial artery embolization may eliminate the need for lung resection in patients presenting with haemoptysis.

• Efficacious antimicrobial therapy for proper management of acute exacerbations of respiratory infections, along with control measures for predisposing infective causes in children, have improved the outlook for bronchiectasis patients.
• Better management options for childhood tuberculosis may contribute to improved prognosis in TB-related cases.
• In general, a better outlook for long-term disease-free periods or permanent cure is associated with the cylindrical or reversible morphological variant.
• The combination of asthma and bronchiectasis is reportedly linked to the poorest prognosis.
• For patients requiring surgical treatment, a good post-operative outlook is associated with:
• A young age
• Localized unilateral disease
• Lower lobe lesions
• Absence of rhinosinusitis
• Absence of obstructive lung disease, with corroborative PFT parameters
• The best prognosis is expected in cases with surgically removable and reversible underlying conditions like a recent aspirated foreign body or a congenital lung cyst.

• Control of common childhood infections associated with destructive inflammation of the bronchi.
• Ensure vaccination – Pertussis and measles vaccinations in the developed world significantly reduced the morbidity burden of complicating bronchiectasis.
• Anti-tuberculous control strategies such as early BCG vaccination and isoniazid chemoprophylaxis can decrease the incidence of TB-related mediastinal/bronchial node complications.
• Streamlining recommendations for the management of asthma.
• Use of anti-pneumococcal conjugate vaccines, especially in at-risk hyposplenic populations like sickle cell disease patients and immunocompromised children in general.
• Yearly mass influenza vaccination.
• Availability of facilities for prompt bronchoscopy to remove aspirated foreign bodies in designated health facilities.