Acute bronchitis

Acute bronchitis is an acute disease of the bronchi, characterized by an inflammation of their mucous membrane, caused by the chemical and biological extension of irritation from the upper air passages, often following a rhinitis or a laryngotracheitis. The larger bronchi are first affected. Affection of the smaller bronchi may be secondary to affection of the larger tubes. Further spread of the infection may cause bronchopneumonia. The condition is also found in association with influenza, measles, scarlet fever, and some of the other acute febrile diseases.

Symptoms: These are retrosternal pain, hoarseness, cough, and often soreness; there may be a slight rise of temperature, though the temperature often remains normal.

Physical Signs: Inspection of the chest is negative; the trachea and pharynx may be infected. Nothing abnormal is elicited by palpation and percussion, but on auscultation the respiratory murmur may be harsh, and numerous large moist or dry rales are found along the large bronchi, which of.ten disappear after cough and expectoration.

Chronic bronchitis

This is a chronic inflammatory condition of the medium sized and small bronchi, associated with destructive changes in the bronchial wall and peribronchial space. As a rule, it is a secondary

disease. It is characterized by dyspnea, cough and various types of expectoration.

Most cases of chronic bronchitis occur in those past middle life. In the young it may be caused 'by some irritating condition within the upper air passages, the trachea or the bronchi, and also by the presence of enlarged tonsils, sinus infections, focal infections, enlarged pendulous uvula, adenoids, congenital malfor­mation of the trachea. A foreign body in the bronchi or lungs may at times be the cause of chronic bronchitis.

Symptoms: These are cough which occurs in paroxysms, copious expectoration, absence of fever, and a history of long-standing cough.

Physical signs: A person suffering from chronic bronchitis is usually emphysematous. Inspection, therefore, will reveal an em-physematous chest. Palpation will give evidence of diminished tactile fremitus throughout the- chest. Percussion will elicit a hyperresonant note, except when associated congestion of the bases is present, in which case, impaired resonance or relative dullness is obtained over these areas. On auscultation the examiner will hear low-pitched, prolonged inspiration, accompanied by low-pitched, prolonged wheezy expiration. The rales heard will be large and small, moist and dry. A profusion of all kinds of rales is usually audible in this class of cases, though the rales may disappear temporarily after the secretion has been coughed up.

Bronchial asthma General Considerations

Familial susceptibility, environmental exposure, and such modifying factors as psychogenic stimuli must all be considered in the etiologic evaluation of an allergic patient. Half of these patients give a definite history of family allergy (rhinitis, asthma, eczema, urticaria). Seventy-five per cent of children with 2 allergic parents will be allergic. A familial history gives no information, however, about the specific clinical expression of the allergy.

Most allergic disorders of the respiratory tract are caused by inhalant allergens, principally pollens (especially the ragweed family), animal danders, and housedusts.

Modifying factors (psychic stress infections, endocrine distur­bances) may precipitate symptoms by upsetting the "balance" between the patient and his allergenic environment. The antigen-antibody reaction then results, and leads to the rapid appearance of reversible tissue changes; increased capillary permeability, in­creased secretion of mucus, spasm of smooth muscle, and increased

numbers of eosinophils in the tissues, secretions and peripheral blood.

The onset of bronchial asthma is usually before 20 years of age.