Common Respiratory Disorders

Common Respiratory Disorders

Chronic Cough

This is a very common problem – perhaps the commonest reason for people visiting their doctor. Any cough lasting longer than 3 weeks can be considered “chronic”. The possible causes are many, ranging from infections to airway problems. Medical consultation is necessary to illicit and treat the causes. Sometimes more than one cause of the cough may exist in a person.


It is NOT normal for a person to feel breathless or even to be aware of one’s breathing when one is at rest, i.e. not engaging in any strenuous activity. So if a person feels any difficulty breathing while at rest, it is an indication for a thorough check as this may be the earliest symptom of many serious disorders.


A common respiratory disorder that afflicts many children and adults – proper treatment not only prevents unnecessary disruption of lifestyle but also reduces the deterioration of lung function that may lead to permanent breathlessness as one grows older.

Exercise is the most common trigger of bronchospasm (narrowing of the airways) in asthmatics and recent studies have found that asthma is the single greatest risk factor for unexplained death occurring among army recruits.

Furthermore, excessive narrowing of the airways (aka exercise-induced bronchoconstriction) may also occur in more than 10% of people without asthma. Hence exercise-induced bronchoconstriction (EIB) presenting as breathlessness, chest tightness or wheezing during exercise is a relatively common problem in athletes or people engaging in strenuous exercises.

Inability to perform up to one’s expected level of exercise requires careful evaluation, including exercise testing.

Chronic Obstructive Pulmonary Disease

Chronic Obstructive Pulmonary Disease (COPD) is an umbrella term that encompasses 2 main disorders – emphysema and chronic bronchitis – diseases that are characterized by obstruction to air flow in and out of the lungs. Emphysema and chronic bronchitis frequently coexist. Thus physicians prefer the term COPD. COPD is a common cause of breathlessness and chronic cough among current or ex-smokers.

For more information on COPD, please visit the Chronic Obstructive Pulmonary Disease Association (Singapore) website ,


This is an infection of the lungs. The microorganisms that can potentially cause this infection are numerous and the condition has gained recent recognition from the SARS (a severe pneumonia caused by a newly identified virus) and the Avian Flu. Appropriate and early treatment of any pneumonia is key to total eradication and complete recovery.


An age-old lung condition that has never quite left us. Would you believe that one third of the world’s population is infected with Tuberculosis (TB)?

TB is still prevalent in Singapore and can affect young and old like. Like pneumonia, early detection is paramount to successful treatment. Complete eradication of TB is possible as we have effective medication against the TB bacilli.

Lung Cancer

The commonest and deadliest type of cancer in many countries, lung cancer is caused by smoking in about 87 percent of cases. However, it is also seen in non-smokers and there is a rising incidence of lung cancer among women. Early detection and treatment certainly helps in this form of cancer.


This is a condition in which air is collecting in the pleural cavity – the space within the chest, between the chest wall and the lung. Usually, this means that there is a leak in the lung that allows the air to escape from it and accumulate in the pleural cavity. The underlying lung may be reduced in size (lung collapse) as a result of the expanding pneumothorax. The treatment will depend on the size of the pneumothorax, the state of the underlying lung, as well as the number of times the condition has recurred.

Pleural Effusion

In this condition, instead of air, fluid has accumulated in the pleural cavity, causing gradual reduction of lung volume and breathlessness may result.

Commonly known as ‘fluid in the lungs’, this is actually abnormal fluid surrounding the lungs within the chest or thorax. Because there is limited space within the thorax, the pleural effusion compresses the lung and hence patients with this condition may present with breathlessness and/or cough.

“Abnormal” Chest X-ray

Many of the above common respiratory conditions may be detected by an abnormal Chest X-ray that is done as part of routine screening. A common abnormality that is detected on screening Chest X-ray is the presence of lung nodule/s that is/are not causing any symptoms. Such radiographic detection may require expert opinion for work-up of the nature of the lung nodule/s. Not all such lung nodules are sinister although the abnormal Chest X-ray may turn out to be the first sign of malignancy in some cases.

The value of routine Chest X-ray screening is debatable but there is recent evidence to suggest that Chest screening radiography detects a substantial number of lung cancers at an early potentially curable stage.

By Dr Ong Kian Chung