Transcript Bronchiectasis

Bronchiectasis
By:
Dr. Wael Thanoon
C.A.B.M.
College of medicine ,Mosul University.
Bronchiectasis means abnormal dilatation of the bronchi.
Chronic suppurative airway infection with sputum production,
progressive scarring and lung damage are present, whatever
the cause.
Aetiology and pathogenesis :
and pathogenesis
Bronchiectasis may result from a congenitalAetiology
defect
affecting
airway ion transport or ciliary function, such as cystic fibrosis
or be acquired secondary to damage to the airways by a
destructive infection, inhaled toxin or foreign body. The result
is chronic inflammation and infection in airways.
Causes of bronchiectasis:
A) Congenital:
Cystic fibrosis
 Ciliary dysfunction syndromes
 Primary ciliary dyskinesia (immotile cilia syndrome)
 Kartagener's syndrome (sinusitis and transposition of the viscera)
 Primary hypogammaglobulinaemia
B) Acquired: children:
 Pneumonia (complicating whooping cough or measles)
 Primary TB
 Inhaled foreign body
C) Acquired: adults
Suppurative pneumonia
 Pulmonary TB: is the most common cause worldwide.
 Allergic bronchopulmonary aspergillosis complicating asthma
 Bronchial tumours



Clinical features:
Physical signs in the chest may be unilateral or bilateral. If
the bronchiectatic airways do not contain secretions and there
is no associated lobar collapse, there are no abnormal physical
signs. When there are large amounts of sputum in the
bronchiectatic spaces, numerous coarse crackles may be heard
over the affected areas. Collapse with retained secretions
blocking a proximal bronchus may lead to locally diminished
breath sounds, while advanced disease may lead to scarring
and overlying bronchial breathing.
Symptoms of bronchiectasis :
1)Cough:Chronic productive cough due to accumulation of pus in dilated bronchi; usually worse in
mornings and often brought on by changes of posture. Sputum often copious and persistently purulent in
advanced disease. Halitosis is a common accompanying feature .
2)Pneumonia and pleurisy: Due to inflammatory changes in lung and pleura surrounding
dilated bronchi when spread of infection occurs: fever, malaise and increased cough and sputum volume, which
may be associated with pleurisy. Recurrent pleurisy in the same site often occurs in bronchiectasis .
3)Haemoptysis: Can be slight or massive and is often recurrent. Usually associated with purulent
sputum or an increase in sputum purulence. Can, however, be the only symptom in so-called 'dry
bronchiectasis‘.
4)Poor
general health:When disease is extensive and sputum persistently purulent, there may be
associated weight loss, anorexia, lassitude, low-grade fever, and failure to thrive in children. In these patients,
digital clubbing is common .
Investigations:
1)Bacteriological and mycological examination of sputum :
In addition to common respiratory pathogens, sputum culture may reveal Pseudomonas
aeruginosa, fungi such as Aspergillus and various mycobacteria. Frequent cultures are necessary to
ensure appropriate treatment of resistant organisms.
2)Radiological examination
Bronchiectasis, unless very gross, is not usually apparent on a chest X-ray. In advanced disease,
thickened airway walls, cystic bronchiectatic spaces, and associated areas of pneumonic
consolidation or collapse may be visible. CT is much more sensitive, and shows thickened dilated
airways.
3)Assessment of ciliary function:
A screening test can be performed in patients suspected of having a ciliary dysfunction syndrome
by measuring the time taken for a small pellet of saccharin placed in the anterior chamber of the
nose to reach the pharynx, when the patient can taste it. This time should not exceed 20 minutes
but is greatly prolonged in patients with ciliary dysfunction. Ciliary beat frequency may also be
assessed using biopsies taken from the nose. Structural abnormalities of cilia can be detected by
electron microscopy
Management :
In patients with airflow obstruction, inhaled bronchodilators and corticosteroids should be used to
enhance airway patency.
1)Physiotherapy:
Patients should be instructed on how to perform regular daily physiotherapy to assist the drainage of
excess bronchial secretions. Efficiently executed, this is of great value both in reducing the amount of
cough and sputum and in preventing recurrent episodes of bronchopulmonary infection. Patients
should adopt a position in which the lobe to be drained is uppermost. Deep breathing followed by
forced expiratory man[oelig ]uvres (the 'active cycle of breathing' technique) is of help in moving
secretions in the dilated bronchi towards the trachea, from which they can be cleared by vigorous
coughing. 'Percussion' of the chest wall with cupped hands may help to dislodge sputum, but does not
suit all patients. Devices which increase airway pressure, either by a constant amount (positive
expiratory pressure mask) or in an oscillatory manner (flutter valve), aid sputum clearance in some
patients, and a variety of techniques should be tried to find one that suits the individual. The
optimum duration and frequency of physiotherapy depend on the amount of sputum, but 5-10 minutes
once or twice daily is a minimum for most patients.
2)Antibiotic therapy:
For most patients with bronchiectasis, the appropriate antibiotics are the
same as those used in COPD; however, in general, larger doses and longer
courses are required, while resolution of symptoms is often incomplete.
When secondary infection occurs with staphylococci and Gram-negative
bacilli, in particular Pseudomonas species, antibiotic therapy becomes more
challenging and should be guided by the microbiological sensitivities. For
Pseudomonas, oral ciprofloxacin (250-750 mg 12-hourly) or ceftazidime by
intravenous injection or infusion (1-2 g 8-hourly) may be required.
Haemoptysis in bronchiectasis often responds to treating the underlying
infection, although in severe cases percutaneous embolisation of the
bronchial circulation by an interventional radiologist may be necessary.
3)Surgical treatment:
Excision of bronchiectatic areas is only indicated in a small proportion of cases. These are usually
young patients in whom the bronchiectasis is unilateral and confined to a single lobe or segment on CT.
Unfortunately, many of the patients in whom medical treatment proves unsuccessful are also unsuitable
for surgery because of either extensive bronchiectasis or coexisting chronic lung disease. In progressive
forms of bronchiectasis, resection of destroyed areas of lung which are acting as a reservoir of infection
should only be considered as a last resort.
Prognosis:
The disease is progressive when associated with ciliary dysfunction and cystic fibrosis, and eventually
causes respiratory failure. In other patients the prognosis can be relatively good if physiotherapy is
performed regularly and antibiotics are used aggressively.
Prevention :
As bronchiectasis commonly starts in childhood following measles, whooping cough or a primary
tuberculous infection, it is essential that these conditions receive adequate prophylaxis and treatment.
The early recognition and treatment of bronchial obstruction is also important
Cystic fibrosis :
Cystic fibrosis (CF) is the most common fatal genetic disease
in Caucasians, with autosomal recessive inheritance, a carrier
rate of 1 in 25 and an incidence of about 1 in 2500 live births
.CF is the result of mutations affecting a gene on the long arm
of chromosome 7 which codes for a chloride channel known as
cystic fibrosis transmembrane conductance regulator (CFTR),
that influences salt and water movement across epithelial cell
membranes. The genetic defect causes increased sodium and
chloride content in sweat and increased resorption of sodium
and water from respiratory epithelium. Relative dehydration of
the airway epithelium is thought to predispose to chronic
bacterial infection and ciliary dysfunction, leading to
bronchiectasis. The gene defect also causes disorders in the gut
epithelium, pancreas, liver and reproductive tract .
Clinical features
The lungs are macroscopically normal at birth, but bronchiolar
inflammation and infections usually lead to bronchiectasis in childhood. At
this stage, the lungs are most commonly infected with Staphylococcus
aureus; however, many patients become colonised with Pseudomonas
aeruginosa by the time they reach adulthood. Recurrent exacerbations of
bronchiectasis, initially in the upper lobes but subsequently throughout both
lungs, cause progressive lung damage resulting ultimately in death from
respiratory failure. Other clinical manifestations are shown in Box 19.38.
Most men with CF are infertile due to failure of development of the vas
deferens, but microsurgical sperm aspiration and in vitro fertilisation are
now possible. Genotype is a poor predictor of disease severity in individuals;
even siblings with matching genotypes may have quite different phenotypes.
This suggests that other 'modifier genes', as yet unidentified, influence
clinical outcome.
Complications of cystic fibrosis:
Respiratory :
Infective exacerbations of bronchiectasis,Spontaneous
pneumothorax,Haemoptysis,Nasal polyps,Respiratory failure,Cor
pulmonale,Lobar collapse due to secretions .
Gastrointestinal: Malabsorption and steatorrhoea,Distal intestinal
obstruction syndrome ,Biliary cirrhosis and portal hypertension,Gallstones
Others :Diabetes (25% of adults),Delayed puberty,Male infertility,Stress
incontinence due to repeated forced cough ,Psychosocial
problems,Osteoporosis,Arthropathy,Cutaneous vasculitis.
Management:
Treatment of CF lung disease :
The management of CF lung disease is that of severe bronchiectasis. All patients with CF who
produce sputum should perform regular chest physiotherapy, and should do so more frequently
during exacerbations. While infections with Staph. aureus can often be managed with oral
antibiotics, intravenous treatment (often self-administered at home through a subcutaneous
vascular port) is usually needed for Pseudomonas species. Regular nebulised antibiotic therapy
(colomycin or tobramycin) is used between exacerbations in an attempt to suppress chronic
Pseudomonas infection.
Treatments that may reduce chest exacerbations and/or improve lung function in CF
1) Nebulised recombinant human DNase 2.5 mg daily used in patient Age ≥ 5, FVC > 40% predicted
2) Nebulised tobramycin 300 mg 12-hourly, given in alternate months used in Patients colonised
with pseudomonas aeruginosa
3)Regular oral azithromycin 500 mg three times/week used in Patients colonised with Pseudomonas
aeruginosa .
Unfortunately, the bronchi of many CF patients eventually become colonised
with pathogens which are resistant to most antibiotics. Resistant strains of P.
aeruginosa, Stenotrophomonas maltophilia and Burkholderia cepacia are the
main culprits, and may require prolonged treatment with unusual
combinations of antibiotics. Aspergillus and 'atypical mycobacteria' are also
frequently found in the sputum of CF patients, but in most cases these behave
as benign 'colonisers' of the bronchiectatic airways and do not require specific
therapy. Some patients have coexistent asthma, which is treated with inhaled
bronchodilators and corticosteroids; allergic bronchopulmonary aspergillosis
also occurs occasionally in CF.
For advanced CF lung disease, home oxygen and NIV may be necessary to treat
respiratory failure. Ultimately, lung transplantation can produce dramatic
improvements but is limited by donor organ availability.
Treatment of non-respiratory manifestations of CF:
There is a clear link between good nutrition and prognosis in CF. Malabsorption
is treated with oral pancreatic enzyme supplements and vitamins. The increased
calorie requirements of CF patients are met by supplemental feeding, including
nasogastric or gastrostomy tube feeding if required. Diabetes eventually appears
in over 25% of patients and often requires insulin therapy. Osteoporosis secondary
to malabsorption and chronic ill health should be sought and treated.
Somatic gene therapy :
The discovery of the CF gene and the fact that the lethal defect is located in the
respiratory epithelium (which is accessible by inhaled therapy) presents an
exciting opportunity for gene therapy. Manufactured normal CF gene can be
'packaged' within a viral or liposome vector and delivered to the respiratory
epithelium to correct the genetic defect. Initial trials in the nasal and bronchial
epithelium have shown some effect, and further trials of nebulised bronchial
delivery are planned. Improved gene transfer efficiency is needed before this
will become a practical clinical treatment.