There are several conditions, which cannot be asthma, but some symptoms are same. Here is a difference :
CHRONIC BRONCHITIS
In an elderly patient, the main difficulty arises in distinguishing asthma from chronic bronchitis and emphysema; sometimes asthma and chronic bronchitis may coexist in a patient. A patient may begin with asthma because of an allergy to pollens, etc., and if improperly or inadequately treated he may develop chronic bronchitis and later on emphysema, as well. On the other hand, a patient may begin with chronic bronchitis, and after many years, develop so-called intrinsic asthma, without any apparent allergic background or known cause and end up as a case of emphysema. Many a time, it is difficult to establish which is the primary disease, and which the complicated one.
CARDIAC ASTHMA
An important disease which simulates bronchial asthma is cardiac asthma. In this condition the breathlessness is, primarily, due to heart disease. This condition also occurs in paroxysms of breathlessness, usually in sleep, but at times also due to exertion. An attack, usually rises to a prak, is accompanied by difficulty in breathing both during inspiration and expiration, and frequently by a terrifying sense of suffocation which causes the patient to sit up or stand erect and even to go to the window for air. The attacks last from a few minutes to a few hours, averaging about an hour, and leave the patient in an exhausted condition for hours or even days.
Cardiac asthma is precipitated by acute failure of the pumping action of the left ventricle of the heart. It is a common feature with hypertensive heart disease and coronary artery disease.
During an attack, the presence of cardiac asthma should be suspected if the patient is more than 40 years old; if he has a previous history of hypertension or heart disease; if he is sweating profusely; if he seeks for fresh air; and if he has a sudden fear of death.
HYSTERICAL ASTHMA
Some patients, in particulary young girls, claim the complaint of asthma but history and examination reveal that all they have is sighing respiration; there is no wheeze and no difficulty in either breathing in or breathing out. Such cases present no serious problem in differential diagnosis.
OTHER CONDITIONS
Diseases which at some stage may simulate bronchial asthma are malignant tumors of the chest, such as lymphosarcoma and Hodgkin’s disease. Pressure of enlarged glands in lung cancer may also give rise to wheezing and breathlessness. The same may happen with the dilatation and swelling (aneurysm) of the wall of the aorta in the chest. Aorta is the most important blood vessel which carries the pure blood from the heart for the rest of the body.