BMJ 2007;335:1089-1093 (24 November), doi:10.1136/bmj.39384.657118.80

Nick H T ten Hacken, specialist registrar in pulmonology, Peter J Wijkstra, specialist registrar in pulmonology, Huib A M Kerstjens, professor of pulmonology
Pulmonary Department, University Medical Centre Groningen, University of Groningen, Postbox 30001, 9700 RB Groningen, Netherlands
Correspondence to: N H T ten Hacken n.h.t.ten.hacken{at}int.umcg.nl
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Patients with bronchiectasis usually need lifelong medical support from their doctor, especially given the frequent episodes of infection. This article focuses on the treatment of bronchiectasis in adults and does not include a discussion of bronchiectasis caused by cystic fibrosis. The prevalence of bronchiectasis not linked to cystic fibrosis is unclear, but every general practitioner in the United Kingdom probably has a few patients.
Bronchiectasis refers to the permanent abnormal dilatation of the central and medium sized bronchi as a result of a vicious cycle of transmural infection and inflammation with mediator release.1 Symptoms include chronic productive cough, wheeze, and dyspnoea. Infective exacerbations are associated with worsening of symptoms and signs of pneumonia. Haemoptysis can occur, but amounts of blood are usually small, and serious haemoptysis requiring selective arteriography and embolisation or surgery is rare.
The most frequently used classification system distinguishes between cylindrical, varicose, and saccular or cystic bronchiectasis.w1 Although insightful, this classification has no clinical or therapeutic uses. A modern clinical definition includes the daily production of mucopurulent phlegm and chest imaging that demonstrates dilated and thickened airways.w2 The clinical suspicion of bronchiectasis can be confirmed by high resolution computed tomography. Characteristic findings include internal bronchial diameters greater than that of the adjacent pulmonary artery, lack of bronchial tapering, presence of bronchi within 1 cm of the costal pleura, presence of bronchi abutting the mediastinal pleura, and bronchial wall thickening.w3
A diagnosis of bronchiectasis should prompt an investigation of
possible causes and associated conditions (table 1
), some of which can be treated.2 Extrinsic
factors, particularly childhood respiratory infections, were an
important cause of permanent bronchial damage in the past. These
days, especially in Western countries with early immunisation and
widespread use of antibiotics, post-infectious damage is a less
prominent cause of the disease, and intrinsic defects are more common
causes. A study of 150 adults with bronchiectasis in the UK found
that 53% of cases were idiopathic; 29% were post-infectious; 8% were
caused by an immune defect, 7% by allergic bronchopulmonary
aspergillosis, 4% by aspiration, 3% by Young's syndrome, 3% by cystic
fibrosis, 3% by rheumatoid arthritis, 1.5% by ciliary dysfunction,
and <1% by miscellaneous causes.3
Bronchiectasis can be treated by pharmacological and non-pharmacological
means (tables 2
and 3
).w4 The box shows an arbitrary step-up scheme
that takes into account the level of evidence and safety risks.
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Antibiotics
Antibiotics are used to treat acute
exacerbations, to prevent exacerbations, or to reduce the bacterial
burden. In general, the outcome of treatment with antibiotics depends
on the severity of the disease. In mild to moderate bronchiectasis
the infection can be completely eradicated, whereas in severe disease
the bronchial tree remains chronically colonised. Antibiotics
with a high penetrance (macrolides, azalides, and quinolones)
are recommended in severe cases because high concentrations of
bacteria are located intraluminally in association with mucus, and
because thickening and scarring of the bronchial wall may reduce
local bioavailability. Pseudomonas aeruginosa is inherently
resistant to most antibiotics at concentrations that are achieved in
vivo. The organism is susceptible to (oral) quinolones,2
but after one or two courses resistance may develop. Patients who
are clinically unwell or do not respond to oral antibiotics
should be admitted to hospital and given intravenous
antibiotics.
Patients who relapse quickly might need prophylactic antibiotics. Three strategies have been described—a high oral dose for a prolonged period (at least four weeks), aerosolised antibiotics (for example, during alternate months), or regular pulsed courses of intravenous antibiotics (for example, two to three week courses with one or two months in between). Prolonged use of oral antibiotics for purulent bronchiectasis was investigated in a recent meta-analysis. It identified six trials that included 302 patients.5 The results of five studies were positive in terms of parameters pertaining to sputum, such as volume or purulence. However, no positive effects were seen on rates of exacerbation, lung function, or death. This contradicts the findings of a recent controlled study that investigated 500 mg of azithromycin given twice a week for six months in 30 patients.6 Pulmonary function tests did not change, but azithromycin significantly decreased the incidence of exacerbations compared with usual care (5 v 16). Inhalation of nebulised antibiotics might be a better route of administration because of its favourable benefit-risk ratio. Gentamicin 40 mg inhaled twice daily for three days improved sputum production, sputum neutrophil activity, airway obstruction, exercise capacity, and nocturnal desaturation compared with placebo.7 Tobramycin 300 mg inhaled twice daily for four weeks eradicated P auruginosa in 35% of patients and improved the medical condition of 62%.8 Ceftazidime 1 g and tobramycin 100 mg inhaled twice daily over 12 months decreased the number of hospital admissions and inpatient days.9
Flu vaccinations reduced the number of flu related exacerbations in chronic obstructive pulmonary disease,w5 so vaccination might have a beneficial effect in bronchiectasis. However, randomised controlled trials of vaccination in patients with bronchiectasis are lacking.
Mucolytics
Mucolytics target hypersecretion or the
physiochemical characteristics of sputum seen in bronchiectasis. They
aim to improve tracheobronchial clearance. In one study, oral
bromhexine (30 mg three times daily) was added to an antibiotic
during acute infective exacerbations. It improved expectoration, the
quantity and quality of sputum, and auscultatory
findings.10 In another study, nebulised recombinant human
DNase I (2.5 mg once or twice a day for two weeks) was given to
patients with stable bronchiectasis. The study found no improvements
in spirometry, quality of life, dyspnoea, safety, or ciliary
transportability of the sputum.11 In a large placebo
controlled study, 349 patients with idiopathic bronchiectasis
in a stable condition inhaled 2.5 mg recombinant human DNase I
for 24 weeks. Pulmonary exacerbations were more frequent and the
decline in FEV1 (forced expiratory volume in one second)
was greater in patients who received DNase than in controls.
These results contrast greatly with the positive effects of
this drug in cystic fibrosis.12
Inhaled mannitol may improve impaired mucociliary clearance by inducing an influx of fluid into the airways, and thereby changing the mucous rheology. One study found that mucociliary clearance was doubled in the central and intermediate lung regions of 11 patients with bronchiectasis directly after inhaling 300 mg mannitol.w6 A follow-up study showed that these effects lasted for at least 24 hours.w7 Inhalation of 400 mg mannitol once daily for 12 days improved the tenacity and hydration of sputum, as well as health status.w8 Mannitol is therefore a promising new drug, especially as it is easier and more hygienic to inhale a dry powder than to use a nebuliser. Large randomised controlled studies are needed, however, to establish its efficacy and tolerability during long term administration.13
Anti-inflammatory agents
Inhaled corticosteroids may
reduce inflammation and improve airway obstruction, as they do in
asthma. To date, three randomised controlled studies have
investigated this hypothesis.w9-w11 Inhaled fluticasone
decreased the density of leucocytes and concentrations of the
inflammatory mediators interleukin 1β, interleukin 8, and leukotriene
B4 in sputum.w11 However, a systematic review found no
significant improvements in lung function.14 Recently, a
large study was published in which 86 patients inhaled fluticasone
500 µg twice daily or placebo for 12 months.15 Twenty four
hour sputum volume improved significantly in patients treated with
fluticasone, but no change was seen in the frequency of
exacerbations, the purulence of sputum, or lung function. Systemic
corticosteroids may be better at penetrating the bronchial wall and
therefore be more effective, but data from randomised controlled
trials are available only for bronchiectasis associated with cystic
fibrosis.16
Leukotriene receptor antagonists are a new class of drugs that is effective in the treatment of asthma. These drugs may be of benefit in bronchiectasis because they inhibit neutrophil mediated inflammation. To date, no randomised controlled trials of these agents have been published, however.17
Non-steroidal anti-inflammatory drugs may also be of use because they inhibit neutrophil function and the release of neutrophil elastase. In a non-controlled open study, eight patients with stable bronchiectasis received 25 mg oral indometacin three times daily for four weeks.w12 Indometacin had a pronounced effect on two of the three neutrophil functions studied—neutrophil chemotaxis and fibronectin degradation were inhibited by more than 50%. However, lung inflammation, sputum volume, and sputum quality did not change. Interestingly, high dose ibuprofen taken consistently for four years significantly slowed the progression of lung disease in patients with cystic fibrosis.w13 Ibuprofen has not yet been investigated in non-cystic fibrosis bronchiectasis.
Macrolides suppress inflammation—independent of their
antimicrobial actions—in airway diseases like asthma, chronic
obstructive pulmonary disease, cystic fibrosis, and diffuse
panbronchiolitis. Indeed, macrolides improved clinical status and
lung function in a few small studies of bronchiectasis.w14-w18 In addition, a randomised placebo controlled trial in children
showed that three months of treatment with clarithromycin decreased
the total number of leucocytes, proportion of neutrophils, and
the concentration of interleukin 8 in bronchoalveolar lavage
fluid.w18 Because bacterial growth was not eliminated the
authors suggested that direct anti-inflammatory effects of
clarithromycin were responsible. This contradicts a randomised
placebo controlled study in adults, however, which showed that eight
weeks of low dose erythromycin did not reduce the number of
leucocytes or the concentrations of interleukin 1
,
interleukin 8, tumour necrosis factor
, or
leukotriene B4 in sputum.w15
Bronchodilators
The mechanisms of expiratory airflow
obstruction in non-cystic fibrosis bronchiectasis are not clear, but
may include excessive production of mucus, distortion of the
bronchial wall, and constriction of smooth muscle. Increased
bronchial hyper-reactivity and some reversibility of the airflow
obstruction with an inhaled bronchodilator are common. As
bronchiectasis may coexist with asthma or chronic obstructive
pulmonary disease, some studies have a high degree of uncertainty as
to whether airway obstruction is due to asthma, chronic obstructive
pulmonary disease, or bronchiectasis (or a combination).
Nevertheless, as many patients show signs of airway obstruction and
hyper-responsiveness, they often receive bronchodilators.
One small Malaysian study gives some information about the reversibility of airway obstruction in bronchiectasis. It included 24 patients with confirmed bronchiectasis but no signs of an acute exacerbation. The study compared 400 µg fenoterol, followed by 5 mg fenoterol 30 minutes later, with 40 µg ipratropium, followed by 500 µg ipratropium.w19 FEV1 increased more than 15% in response to one or both bronchodilators in 11 patients—five responded to both, three to fenoterol alone, and three to ipratropium alone. This small study suggests a significant response to bronchodilators in a subset of patients.
Cochrane reviews found no randomised controlled trials on short acting β2 adrenergic agonists,18 long acting β2 adrenergic agonists,19 anticholinergic therapy,20 or oral methylxanthines21 in patients with non-cystic fibrosis bronchiectasis. Good quality studies are therefore urgently needed in this field.
Bronchopulmonary hygiene physical
therapy
Bronchopulmonary hygiene physical therapy is a form of
chest physical therapy that aims to remove lung secretions in
patients with acute and chronic airway diseases. Many active and
passive techniques are available (table 2
),
and the technique chosen varies between institutes and physical
therapists.w20 w21 The evidence in support of these
techniques is variable and the literature is
conflicting.w20 Two systematic reviews found insufficient
evidence to support or refute this form of therapy.22
23
Exercise training
The role of pulmonary rehabilitation
and inspiratory muscle training has been investigated in only one
randomised controlled trial. It compared an eight week training
programme of pulmonary rehabilitation alone, pulmonary rehabilitation
plus inspiratory muscle training, and a control group.w22
The authors concluded that pulmonary rehabilitation does improve
exercise tolerance. Simultaneous inspiratory muscle training offered
no additional benefit.
Surgery
If the area of bronchiectasis is localised and
the patient's symptoms are debilitating or life threatening, surgical
resection has long been thought to be of benefit. This assumption
was based on several non-randomised controlled studies of
uncertain value. A Cochrane review updated in 2002 found no
randomised clinical trials—just case series or case-control
studies.24 The largest case-control study included
pneumonectomy in 190 cases, lobectomy in 202 cases, bilobectomy in 23
cases, and lobectomy combined with segmental resection in 72
cases.25 Overall mortality was 3.5%, and 71% of patients
had no symptoms during follow-up (four months to 10 years). The
authors therefore concluded that surgery was preferable to
conventional medical treatment.
The general consensus is that acute exacerbations should be treated promptly with short courses of systemic antibiotics. In stable bronchiectasis, a high level of evidence exists for the use of prolonged and aerosolised antibiotics, but this form of treatment is mostly reserved for patients with frequent exacerbations. Because of the low level of evidence we cannot recommend the use of mucolytics, anti-inflammatory agents, or bronchopulmonary hygiene therapy on a routine basis. Surgery may be considered if the area of bronchiectasis is localised and the patient's symptoms are debilitating or life threatening. Well powered studies to investigate the effects of well defined treatment regimens on important short and long term outcomes of bronchiectasis are urgently needed.
Contributors: NHTtH selected the literature and wrote all versions of the article. HAMK and PJW commented on the various drafts of the manuscript. All authors discussed the grading the levels of evidence and recommendations. NHTtH is guarantor.
Competing interests: None declared.
Provenance and peer review: Commissioned; externally peer reviewed.