咳嗽－－臨床鑑別診斷

Cough-Clinical Differential Diagnosis

咳嗽為常見的臨床主訴，呼吸系統及非呼吸系統的疾病均可引發咳嗽，其鑑別診斷需靠詳實的病史詢問、理學檢查及診斷工具。急性咳嗽通常是由呼吸系統的發炎性病變引致。慢性咳嗽而胸部X光片正常者，需考慮鼻涕倒流症候群、支氣管性哮喘及胃食道逆流；Angiotensin converting enzyme inhibitor （ACEI）引發的咳嗽在高血壓族群亦非罕見。慢性咳嗽而X光片不正常者，常見的是慢性炎症，例如結核（tuberculosis）、支氣管擴張（bronchiectasis）、慢性阻塞性肺病（chronic obstructive pulmonary disease）及腫瘤（neoplasm）。其他一些少見的疾病則有慢性心衰竭（congestive heart failure）、縱膈腔疾病（mediastinal disease）、肋膜疾病（pleural disease）及肺間質性病變（interstitial lung disease）。

Cough, stimulated mostly by vagal reflex, is a defense mechanism of the lung. It can he generated hr different causes including a variely of non-airway related diseaces. Detail history and characteristics of cough (such as onset, duration, productive or non-productive, timing and associated symptoms) are useful in diagnosis. Acute cough is usually a result of acute infectious diseases of airway. Chronic cough in those who have normal chest X-ray films are usually caused hr cough variant asthma, post-nasal drip syndrome (PNDS) and gastroesophageal reflux disease (GERD). While cough induced by angiotensin converting enzyme inhibitors (ACEI) should always be considered in patients receiving these drugs. Meanwhile, chronic cough with abnormal X-ray films may include lung tumors and chronic inflammations such as tuberculosis, bronchiectasis, and chronic obstructive pulmonary disease (COPD), etc.