Emphysema Clinical Presentation
- Author: Kamran Boka, MD, MS; Chief Editor: Zab Mosenifar, MD, FACP, FCCP more...
Most patients seek medical attention late in the course of their disease, usually ignoring smoldering symptoms that start gradually and progress over the course of years. Patients will adapt and modify their lifestyles in order to minimize dyspnea and ignore cough and mucus production. With questioning, a multiyear history can be elicited.
Generally, patients present in their fifth decade of life with a productive cough or acute chest illness. This cough, commonly referred to as a "smoker's cough," typically is worse in the morning with finite production of clear-to-white sputum. The cause of this is usually undiagnosed concomitant chronic bronchitis.
Dyspnea, emphysema's most significant symptom, does not generally occur until the sixth decade of life. By the time the forced expiratory volume in 1 second (FEV1) has fallen to 50% of predicted, the patient is breathless upon minimal exertion.
Wheezing may occur in some patients, particularly during exertion and exacerbations. Listen to typical wheezing with the link below.
Auscultation of patient during exacerbation of COPD/emphysema. Courtesy of James Heilman, MD, published by Wikipedia.
AAT-deficient patients present earlier than other COPD patients, usually in their fourth or fifth decade of life, with severe AAT deficiency mainly affecting the lungs and the liver. Liver dysfunction dominates the clinical picture in the first decade of life. Patients who are homozygous (Pi ZZ) develop emphysema with the following distinctive features: early presentation (< 45 y), predilection of emphysematous changes in the lung bases, and the panacinar morphological pattern.
Emphysema’s physiologic hallmark physical examination finding is the limitation of expiratory flow with relative preservation of inspiratory flow. It takes longer to exhale than it does to inhale. Measurement of the forced expiratory time maneuver is a simple bedside test; a forced expiratory time more than 6 seconds indicates severe expiratory airflow obstruction. The forced expiratory volume in one second (FEV1) and the forced vital capacity (FVC) are important in determining flows. The ratio of the two (FEV1/FVC) results as a percentage during the spirometry portion of pulmonary function testing and is the objective diagnostic means of labeling a patient with COPD.
Although the sensitivity of the physical evaluation in mild-to-moderate disease is relatively poor, the physical signs are quite sensitive and specific in severe disease. Patients with severe disease may experience tachypnea and dyspnea with mild exertion.
The respiratory rate increases in proportion to disease severity with the use of accessory respiratory muscles and paradoxical contraction of lower intercostal spaces becoming evident during exacerbations.
In end-stage emphysema, cyanosis, elevated jugular venous pressure, atrophy of limb musculature, and peripheral edema due to the development of pulmonary hypertension, right-to-left shunting, and/or right heart failure can easily be observed.
Thoracic examination reveals a 2:1 increase in anterior to posterior diameter (“barrel chest”), diffuse or focal wheezing, diffusely diminished breath sounds, hyperresonance upon percussion, prolonged expiration, and/or hyperinflation on chest radiographs.
Smoking is by far the single most clearly established environmental risk factor for emphysema/chronic bronchitis. One in five persons who smokes develops COPD, and 80-90% of COPD patients have a smoking history.
AAT deficiency syndromes
This syndrome leads to protease-antiprotease imbalance and unopposed action of neutrophil elastases.
Intravenous drug user
Emphysema occurs in approximately 2% of persons who use intravenous drugs. This is attributed to pulmonary vascular damage resulting from the insoluble filler (eg, cornstarch, cotton fibers, cellulose, talc) contained in methadone or methylphenidate.
The bullous cysts found in association with intravenous use of cocaine or heroin occur predominantly in the upper lobes. In contrast, methadone and methylphenidate injections are associated with basilar and panacinar emphysema.
Immune deficiency syndromes
Human immunodeficiency virus (HIV) infection was found to be an independent risk factor for emphysema, even after controlling for confounding variables such as smoking, intravenous drug use, race, and age.
Apical and cortical bullous lung damage occurs in patients who have autoimmune deficiency syndrome and Pneumocystis carinii infection. Reversible pneumatoceles are observed in 10-20% of patients with this infection.
Hypocomplementemic vasculitis urticaria syndrome (HVUS) may be associated with obstructive lung disease.
Other sequellae include angioedema, nondeforming arthritis, sinusitis, conjunctivitis, and pericarditis.
Cutis laxa, a disorder of elastin that is characterized most prominently by the appearance of premature aging. The disease is usually congenital, with various forms of inheritance (ie, dominant, recessive). Precocious emphysema has been described in association with cutis laxa as early as the neonatal period or infancy. The pathogenesis of this disorder includes a defect in the synthesis of elastin or tropoelastin.
Marfan syndrome is an autosomal dominant inherited disease of type I collagen characterized by abnormal length of the extremities, subluxation of the lenses, and cardiovascular abnormality. Pulmonary abnormalities, including emphysema, have been described in approximately 10% of patients.
Ehlers-Danlos syndrome refers to a group of inherited connective-tissue disorders with manifestations that include hyperextensibility of the skin and joints, easy bruisability, and pseudotumors.
Salla disease is an autosomal recessive storage disorder described in Scandinavia; the disease is characterized by intralysosomal accumulation of sialic acid in various tissues. The most important clinical manifestations are severe mental retardation, ataxia, and nystagmus.
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