এই টপিকে মেডিসিন, সার্জ়ারী সহ বিভিন্ন টপিকের পিডিএফ বই, জার্ণাল এর ডাউনলোড লিঙ্ক দেয়া হবে। পুরো টপিক ইংরেজি তে।
Bronchiectasis - Non Cystic Fibrosis - Guideline
AUTHOR :
Britsih Thoracic Society
How has the guideline been designed?
The guideline is divided into sections covering different aspects of the management of the condition. Guidance for children and adults is dove- tailed together throughout to avoid repetition while acknowledging differ- ences between these groups. Areas of particular or sole relevance to one or other of these groups are indicated. Sections 2 and 3 cover the back- ground, clinical assessment and investigation of patients (including appropriate radiological and laboratory investigations). The principles and broad approach to management are discussed in Section 4 including rec- ommendations for physiotherapy and non-antibiotic drug treatment. The use of antibiotics is covered in Section 5 and surgery and the manage- ment of advanced disease is covered in Section 6.
Definition
This guideline refers to the investigation and management of patients with symptoms of persistent or recurrent bronchial sepsis related to irre- versibly damaged and dilated bronchi, namely, clinical bronchiectasis. It does not cover the management of cystic fibrosis (CF) and, for the pur- poses of the guideline, ‘bronchiectasis’ is synonymous with the term ‘non- CF bronchiectasis’. Likewise, it does not focus on traction bronchiectasis secondary to other lung pathologies, particularly the interstitial lung diseases, which is commonly asymptomatic.
What are the pathology and underlying causes?
Bronchiectasis is a persistent or progressive condition characterised by dilated thick-walled bronchi. The symptoms vary from intermittent episodes of expectoration and infection localised to the region of the lung that is affected to persistent daily expectoration often of large volumes of purulent sputum. Bronchiectasis may be associated with other non-spe- cific respiratory symptoms including dyspnoea, chest pain and haemop- tysis, and may progress to respiratory failure and cor pulmonale.
The underlying pathological process is damage to the airways which results from an event or series of events where inflammation is central to the process. This is easy to understand as part of the ‘vicious circle’ hypothesis which has been applied to bronchiectasis and has been the major factor influencing current disease management.
The lung is continuously exposed to inhaled pathogens and (in many countries) environmental pollutants. The lung has a sophisticated primary and secondary defence system that maintains sterility of the normal lung. If this defence system is breached as in disorders of mucociliary clear- ance or specific antibody deficiencies, the lung becomes susceptible to infection, colonisation (the persistence of bacteria in the lower respira- tory tract) occurs and the subsequent inflammation that causes airway damage further impairing host defences. Thus, once established, the defective defences can lead to a self-perpetuating cycle of events that facilitate bacterial colonisation and airway sterility becomes unlikely.
Primary defects in the lung defences are uncommon in patients investigated as adults, suggesting they are either subtle or do not influence the primary event. However, immunodeficiency may be more common when bronchiectasis presents in childhood.232 Episodes causing clear lung dam- age such as previous pneumonias, gastric aspiration or viral illnesses in childhood would represent such initiating events, although recent evidence suggests these may be less common. The damage to the airway by such episodes would particularly impair the normal mucociliary function and hence clearance of inhaled pathogens initiating the inflammatory cycle.
However, despite many studies over the years using modern immuno- logical techniques, not only have few primary deficiencies of host defences been found but up to 40% of patients do not even have a clear defining event that appears to initiate the process.
What is the outlook for these patients?
Most of the information on long term outcome is from historical data and suggests that antibiotic therapy has had an effect. For instance, in the 1940s most patients diagnosed with bronchiectasis died before the age of 40 years but, by the 1960s, the average age of death had risen to 55 years. Nevertheless, this still indicates a significant reduction in life expectancy in patients with bronchiectasis. More recent data suggest a better prognosis,373 although it is recognised that the general health of patients with bronchiectasis can be poor251 and certain subsets (particu- larly those colonised with Pseudomonas aeruginosa ) are particularly affected, with continued ill health and progressive deterioration.
