Cough and expectoration

 Cough is a familiar but complex reflex, and is one of the most common presenting complaints.  Definition: cough is a sudden explosive expiratory maneuver that tends to clear material from the airways.  cough is caused by stimulating the medullary cough center or associated higher centers.

Etiology  Diseases of respiratory tract : any stimulus on respiratory tract may cause cough. (pharynx, laryngeal, trachea, bronchus and alveolus)  Diseases of pleura: pleuritis, pleural carcinomatosis and pneumothorax (spontaneous, traumatic or induced )

 Central nervous system: encephalitis and meningitis( act on medullary cough center )  Cardiovascular system: left heart failure or lung infarction which cause secretion in alveolus and bronchus

Expectoration  Sputum production (expectoration): A major function of the cough reflex is to help clear secretions from the airways, particularly to help expel them through the larynx.  Examination of sputum is important for diagnosis:

 Its gross appearance (from clear white mucus to yellowish, green, or brown purulent material)  Presence of squamous cells suggests that the material came from above the larynx;  true sputum expelled from the airways is characterized by the presence of alveolar macrophages or histiocytes.

 Wright's stain will show the proportion of eosinophils, and eosinophilia suggests a probable allergic origin.  Neutrophils predominate more often in purulent sputum, indicating an inflammatory and usually an infectious process.  A Gram stain will confirm the presence of bacteria and begin their categorization

Clinic significance  Cough induced by postural change may suggest chronic lung abscess, cavitary TB, bronchiectasis, or pedunculated ( 有茎的 ) tumor,  cough associated with eating suggests a disturbance of the swallowing mechanism, or possibly a tracheoesophageal fistula.

 Cough that appears on exposure to cold air or exercise may suggest asthma.  A morning cough persisting until sputum is expectorated typifies chronic bronchitis.  Coughing associated with rhinitis or wheezing, or that is seasonal in incidence, may be an allergic response.

 the irritable, dry, barking cough associated with acute tracheitis;  the low-pitched, blowing, "bovine" cough without an explosive start, heard in a patient with a paralyzed recurrent laryngeal nerve  cough associated with fever suggests respiratory infection, pleuritis and TB

 cough associated with chest pain indicates pneumonia, pleuritis, lung cancer or infarction and spontaneous pneumothorax  Clubbing of the fingers (enlargement of the terminal digital phalanges with loss of the nail bed angle) indicates lung tumor, bronchiectasis or lung abscess

 Changes in character of sputum (from clear white mucus to yellowish, green, or brown purulent material) are important indicators of infection.  Blood streaking and frank hemoptysis are important for TB, bronchiectasis and carconoma  Gritty material in sputum, characteristic of broncholithiasis,

History-taking  how long cough has been present;  whether it began suddenly;  if it has changed recently;  what factors influence it (eg, cold air, talking, posture, eating or drinking, time of day);  whether it is associated with sputum production, chest or retrosternal or throat pain, dyspnea, hoarseness （嘶哑、刺耳）, dizziness, or other symptoms.

Hemoptysis

 Coughing up blood as a result of bleeding from the respiratory tract.  Blood-streaked sputum is a rather common complaint but is usually nonthreatening

 Inflammatory causes account for 80 to 90% of hemoptysis. Acute or chronic bronchitis is probably the most common cause, since bronchitis and bronchiectasis cause about 50% of all cases

 Tumors (especially carcinoma), perfused primarily by bronchial vessels, account for about 20% of cases.  Pulmonary infarction in association with thromboembolism and left heart failure (especially secondary to mitral stenosis) are less common causes of hemoptysis

 Other less common causes (eg, primary bronchial adenoma, arteriovenous malformations) are disproportionately important because of their tendency to cause severe bleeding

 Hemoptysis must be differentiated from hematemesis (etiology, concomitant symptoms, color, sputum, acidity or basicity, melanism) and from blood dripping into the tracheobronchial passages from the nose, mouth, or nasopharynx.

Etiology CONDITIONS ASSOCIATED WITH HEMOPTYSIS  Larynx and pharynx Lymphoma Carcinoma Tuberculous ulceration

 Trachea and large bronchi Benign or malignant primary tumor (carcinoma and adenoma) Telangiectasia （毛细血管扩张） Erosion by an aortic aneurysm Bronchogenic cyst Broncholithiasis （支气管结石） Erosion by a caseocalcific node Erosion by a tumor from nodes, esophagus, or other mediastinal structures Severe acute bronchitis Trauma

 Smaller bronchial structures Carcinoma Adenoma (carcinoid or cylindromatous) Acute bronchitis Bronchiectasis Bronchopulmonary sequestration Chronic bronchitis Trauma

 Pulmonary parenchyma Primary or metastatic tumor Infarct Abscess Active granulomatous disease (tuberculous, fungal, parasitic, luetic （梅毒的） ) Fungus ball (Aspergillus) in an old cavity Acute pneumonia Idiopathic hemosiderosis Goodpasture's syndrome or variants Trauma

 Cardiovascular Left ventricular failure Mitral stenosis Pulmonary embolism/infarct Primary pulmonary hypertension Pulmonary arteriovenous malformation Atrial myxoma （粘液瘤） Fibrous mediastinitis with pulmonary vein obstruction Aortic aneurysm with leakage into the pulmonary parenchyma

 Clotting defects Thrombocytopenia Vitamin K-Dependent factors: prothrombin (II), Stuart factor (X), factor VII, Christmas factor (IX) Diffuse intravascular coagulation Heparin therapy Fibrinolytic therapy: urokinase, streptokinase Miscellaneous congenital coagulation defects

Clinic manifestations  Age: hemoptysis of young people common indicates TB, bronchiectasis, mitral stenosis. bronchogenic carcinoma must be strongly suspected in smokers who have hemoptysis and who are  40 yr old (>20 cigarettes/day *20 years)

 Quantity of hemoptysis: small: <100ml/24h intermediate: ml/24h massive: >500ml/24h(chronic lung abscess, cavitary TB, bronchiectasis)

 Color and characteristic: cardinal red sputum: TB, lung abscess, bronchiectasis and clotting defects ferrugineous sputum: pneumonia, parasitic wine sputum: mitral stenosis, infarct frothy and blood-tinged sputum: left heart failure

Concomitant symptoms  Fever  Chest pain  Cough  Purulent sputum  Bleeding  Jaundice