Synonyms.—Pseudo-membranous Bronchitis; Croupous Bronchitis; Plastic Bronchitis.
Definition.—An acute or chronic inflammation of the bronchial tubes and characterized by the formation of a false membrane or fibrinous casts.
Etiology.—Certain conditions predispose to this affection, although the specific cause' is not known. It occurs far more frequently in male subjects than in the female, and between the age of twenty and forty, although it may occur at any period of life, and follows the breaking up of winter, or the early spring months.
It is associated with tuberculosis and certain skin diseases, such as pemphigus, impetigo; and herpes. Heredity may play some part in its causation. The inhalation of steam and noxious gases is sometimes followed by plastic bronchitis; while erysipelas, scarlet fever, and other infectious diseases have preceded it.
Pathology.—The exudate or pseudo-membrane is usually found in the large tubes, although not infrequently involving the smaller branches. The exudate is found upon the mucous membrane, and forms casts of the tubes. These casts may be hollow or solid, being filled with leukocytes, blood corpuscles, epithelial cells, and sometimes the Charcot-Leydon crystals.
The composition of the casts is not very well understood, although generally believed to be fibrinous. The casts are expectorated in the form of jelly-like mucus, and when placed in water may be unrolled, revealing- the casts of the bronchi.
Symptoms.—The acute form, which is quite rare, may result fatally in a short time, owing to the dyspnea, due to occlusion of the bronchi. It begins with a chill or rigor, followed by high febrile reaction. The pulse is sharp and frequent, the respiration hurried, with a sense of constriction in the chest. Dyspnea early comes on, attended by paroxysms of coughing. At first the cough is dry, with but little expectoration, though often of a bloody character. Soon secretion becomes more profuse, and a paroxysm of coughing is followed by expectoration of some of the casts, not infrequently a profuse hemorrhage following.
With the subsidence of the fever, the secretion becomes more free, the dyspnea disappears, and the patient is convalescent. On the other hand, the obstruction may be so great as to lead to fatal asphyxiation.
Chronic Form.—The chronic form is usually milder in character and recurs at regular intervals. The earlier symptoms are those of ordinary bronchitis; but as the disease progresses, dyspnea becomes more marked and the cough paroxysmal in character. Expectoration is more profuse than in the acute form, the jelly mass expectorated revealing complete molds of the tubes. The casts may be found mixed with pus and blood.
The general symptoms are the same as those of chronic bronchitis. The physical signs do not differ materially from those of ordinary bronchitis. At first the dry, sibilant rhonchus is heard, changing to the mucous, as secretion becomes established.
Diagnosis.—The diagnosis is made from ordinary bronchitis by the greater dyspnea, the paroxysmal character of the cough, and finding the casts when the sputum is placed in water. From diphtheria, by the laryngeal complication and grave systemic symptoms of the latter.
Prognosis.—The acute form is a grave disease, and the prognosis should be guarded. The chronic form generally results favorably, although attacks may recur for years. Where there is a history of tuberculosis the outlook is not so favorable.
Treatment.—The treatment in the acute form will be similar to that of pseudo-membranous croup, the object being to soften and dislodge the membrane. Inhalations of medicated steam, produced by adding eucalyptus, lobelia, hops, and remedies of like character, to boiling water, will be found beneficial. Inhalation of lime-water is also to be advised.
Internally, lobelia or the old antispasmodic tincture will be found useful. With the loosening of the membrane, sanguinaria will be found helpful as a stimulating expectorant. The chronic form will be treated on the same lines as chronic bronchitis. The general health must be improved, and the local treatment will correspond with that for the chronic form.