By: Dr. Wael Thanoon C.A.B.M.S. College of medicine ,Mosul University. Bronchiectasis By: Dr. Wael Thanoon C.A.B.M.S. College of medicine ,Mosul University.

Aetiology and pathogenesis : 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 : Bronchiectasis may result from a congenital 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. Aetiology and pathogenesis

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.

Prognosis: Prevention : 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.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.