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Findings are nonspecific and may be attributed to other conditions. Most commonly, crackles, rhonchi, wheezing, and inspiratory squeaks may be heard upon auscultation. General findings may include digital clubbing, cyanosis, plethora, wasting, and weight loss. Nasal polyps and signs of chronic sinusitis may also be present. In advanced disease, the physical stigmata of cor pulmonale may be observed.
· Crackles and rhonchi are often observed in association with active infections and acute exacerbations.
· Scattered wheezing may be heard in approximately one third of patients. Wheezing may be due to airflow obstruction from secretions, destruction of the bronchial tree leading to airway collapsibility, or concomitant conditions.
· Digital clubbing is an inconsistent finding in approximately 2-3% of patients. It is more frequent in patients with moderate-to-severe bronchiectasis.
· Cyanosis and plethora are rare findings secondary to polycythemia from chronic hypoxia.
· Wasting and weight loss are suggestive of advanced disease but are not diagnostic of bronchiectasis.
· In severe cases, findings are consistent with cor pulmonale. Right-sided heart failure may be observed, including peripheral edema, hepatomegaly, and hypoxia. This can ultimately lead to progressive respiratory failure.
Examination
Chest radiography is usually the first imaging examination, but the findings are often nonspecific and the images may appear normal. High-resolution computed tomography (HRCT) scanning has become the imaging modality of choice for demonstrating or ruling out bronchiectasis and its extent. HRCT scanning also helps clinicians evaluate the status of the surrounding lung tissue and exclude other lesions such as neoplasms/
Bronchography was the classic modality used and, until the advent of HRCT scanning, was the only imaging method to demonstrate bronchiectasis. Bronchography is performed by instilling an iodine-based contrast material via a catheter or bronchoscope, but it is rarely, if ever, performed today, as HRCT scanning has replaced it as the diagnostic modality of choice. HRCT scanning is noninvasive and has a sensitivity of 96% and a specificity of 93%.
Laboratory testing may be helpful:
Bronchoscopy is not helpful in diagnosing bronchiectasis, but it may be used to identify underlying abnormalities, such as tumors and foreign bodies.
Medical Care
The goals of therapy are to improve symptoms, to reduce complications, to control exacerbations, and to reduce morbidity and mortality. Early recognition is essential in bronchiectasis and associated conditions. Additionally, management of underlying conditions, which may include the use of intravenous immunoglobulin or intravenous AAT therapy, is essential to the overall treatment.
Antibiotics and chest physiotherapy are the mainstay modalities. Other modalities (beyond those for specific associated conditions) may include bronchodilators, corticosteroid therapy, dietary supplementation, and oxygen or surgical therapies. Admitting patients with severe exacerbations of bronchiectasis to the hospital and treating them with intravenous antibiotics, bronchodilators, aggressive physiotherapy, and supplemental nutrition is not uncommon.
Available treatment guidelines include:
· General therapy
o Patients should stop smoking.
o Patients should avoid second-hand smoke.
o Patients should have adequate nutritional intake with supplementation, if necessary.
o Immunizations for influenza and pneumococcal pneumonia are recommended.
o Immunizations for measles, rubeola, and pertussis should be confirmed.
o Oxygen therapy is reserved for patients who are hypoxemic with severe disease and end-stage complications, such as cor pulmonale.
o Patients with CF should be cared for at specialized CF treatment centers that address all aspects of the disease, including nutritional and psychologic aspects.
· Antibiotics
o Oral, parenteral, and aerosolized antibiotics are used, depending on the clinical situation.
o In acute exacerbation, broad-spectrum antibacterial agents are generally preferred. However, if time and the clinical situation allows, then sampling respiratory secretions during an acute exacerbation may allow treatment with antibiotics based on specific species identification.
o Acceptable choices for the outpatient who is mild to moderately ill include amoxicillin, tetracycline, trimethoprim-sulfamethoxazole, a newer macrolide (eg, azithromycin or clarithromycin ), a second-generation cephalosporin, or one of the fluoroquinolones. In general, the duration is 7-10 days.
o For patients with moderate-to-severe symptoms, parenteral antibiotics, such as an aminoglycoside (gentamicin, tobramycin) and an antipseudomonal synthetic penicillin, a third-generation cephalosporin, or a fluoroquinolone, may be indicated. Patients with bronchiectasis from CF are often infected with mucoid Pseudomonas species, and, as such, tobramycin is often the drug of choice for acute exacerbation.
o Infection with MAC provides special treatment challenges. For the treatment of MAC in the setting of bronchiectasis, the American Thoracic Society recommends a 3- to 4-drug treatment regimen with clarithromycin, rifampin, ethambutol, and possibly streptomycin that is continued until the patient's culture results are negative for 1 year. The typical duration of therapy may be 18-24 months.
o Additionally, some patients with chronic bronchial infections may need regular antibiotic treatment to control the infectious process. Some clinicians prefer to prescribe antibiotics on a regular basis or for a set number of weeks each month. The oral antibiotics of choice are the same as those mentioned previously. Potential regimens include daily antibiotics for 7-14 days of each month, alternating antibiotics for 7-10 days with antibiotic-free periods of 7-10 days, or a long-term daily dose of antibiotics. For patients with severe CF and bronchiectasis, intermittent courses of intravenous antibiotics are sometimes used.
o In the past several years, the nebulized route of antibiotic administration has received more attention because it is capable of delivering relatively high concentrations of drugs locally with relatively few systemic adverse effects. This is particularly beneficial in treating patients with chronic infection from P aeruginosa. Currently, inhaled tobramycin is the most widely used nebulized treatment for patients with bronchiectasis from either CF or non-CF causes of bronchiectasis. Gentamicin and colistin have also been used.
· Bronchial hygiene
o Postural drainage with percussion and vibration is used to loosen and mobilize secretions. Other devices available to assist with mucus clearance include flutter devices, intrapulmonic percussive ventilation devices, and incentive spirometry. However, consistent benefits from these techniques are lacking and vary with patient motivation and knowledge.
o Nebulization with sodium chloride solutions appears to be beneficial, particularly in patients with CF-related bronchiectasis. Mucolytics, such as acetylcysteine, are also often tried but a universal benefit does not seem to exist. However, maintaining adequate general hydration, which may improve the viscidity of secretions, is important.
· Bronchodilators
o Bronchodilators, including beta-agonists and anti-cholinergics, may help some patients with bronchiectasis, presumably reversing bronchospasm associated with airway hyperreactivity and improving mucociliary clearance.
· Anti-inflammatory medication
o The rationale is to modify the inflammatory response caused by the microorganisms associated with bronchiectasis and subsequently reduce the amount of tissue damage. Inhaled corticosteroids, oral corticosteroids, leukotriene inhibitors, and nonsteroidal anti-inflammatory agents have all been examined. Although evidence tends to support some benefit from the use of these agents, findings are not universally definitive.
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