Bronchiectasis (Gr. βρόγχια, bronchial tubes, and ἒκτασις, extension), dilatation of the bronchi, a condition occurring in connexion with many diseases of the lungs. Bronchitis both acute and chronic, chronic pneumonia and phthisis, acute pneumonia and broncho-pneumonia, may all leave after them a bronchiectasis whose position is determined by the primary lesion. Other causes, acting mechanically, are tracheal and bronchial obstruction, as from the pressure of an aneurism, new growth, etc. It used to be considered a disease of middle age, but of late years Dr Walter Carr has shown that the condition is a fairly common one among debilitated children after measles, whooping cough, etc. The dilatation is commonly cylindrical, more rarely saccular, and it is the medium and smaller sized tubes that are generally affected, except where the cause is mechanical. The affection is usually of one lung only. Emphysema is a very common accompaniment. Though at first the symptoms somewhat resemble those of bronchitis, later they are quite distinctive. Cough is very markedly paroxysmal in character, and though severe is intermittent, the patient being entirely free for many hours at the time. The effect of posture is very marked.

If the patient lie on the affected side, he may be free from cough the whole night, but if he turn to the sound side, or if he rises and bends forward, he brings up large quantities of bronchial secretion. The expectoration is characterized by its abundance and manner of expulsion. Where the dilatation is of the saccular variety, it may come up in such quantities and with so much suddenness as to gush from the mouth. It is very commonly foetid, as it is retained and decomposed in situ. Dyspnoea and haemoptysis occasionally occur, but are by no means the rule. If pyrexia is present, it is a serious symptom, as it is a sign of septic absorption in the bronchi, and may be the forerunner of gangrene. If gangrene does set in, it will be accompanied by severe attacks of shivering and sweating. Where the disease has lasted long, clubbing of fingers and toes is very common. The diagnosis from putrid bronchitis is usually fairly easily made, but at times it may be a matter of extreme difficulty to distinguish between this condition and a tuberculous cavity in the lung. Nothing can be done directly to cure this disease, but the patient's condition can be greatly alleviated. Creosote vapour baths are eminently satisfactory.

A mechanical treatment much recommended by some of the German physicians is that of forced expiration.