Bronchitis is acute inflamation of the tracheobronchial tree, generally self -limited and with eventual complete healing and return to function. Though commonly mild, bronchitis may be serious in debilitated patients and in those with chronic lung or heart disease. Pneumonia is a critical complication.
Acute bronclitis can be caused by infection or by exposure to irritants. Infectious bronchitis occur most often during the winter and is most often caused by viruses. Even after a viral infection has resolved the irritation it causes can continue to cause symptoms for weeks. Infectious bronchitis may also be caused by bacteria, and it often follows an upper respiratory viral infection.
Myceplasma pneumoniae and chamyclia pneumonie often cause bacterial bronchitis in young adults. Among middle-aged and older people, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarhalis are the most common organisms causing bacterial bronchitis.
Viral bronchitis may be caused by a number of common viruses, including the influenza virus. A person often has a combination of bacterial and viral bronchitis. Smokers and people who have chronic lung disease may have repeated attacks of acute bronchitis because mucous is less able to drain from their airways.
Malnutrition increases the risk of upper respiratory tract infections and subsequent acute bronchitis, especially in children and older people. Chronic sinus infection bronchiactasis, allergies also increase the risk of repeated episodes of bronchitis. Irritative bronchitis may be caused by exposure to various mineral and vegetable dusts.
Exposure to fumes from strong acids, ammonia, some organic solvents, chlorine, hydrogen sulphide, sulfur dioxide and bromine can also cause irritative bronchitis.
Pathology and pathophysiology
Hyperemia of the mucous membranes is the earliest change, followed by desquamation, oedema, lencocytic infiltration of the submucosa, and production of the sticky or mucopurulent exudate.
The protective functions of bronchial cilia, phagocytes, and lymphatics are distubbed, and bacteria may invade the normally sterile bronchi with consequent accumulation of cellular debris and mucopurulent exudate. Cough, though distressing, is essential to eliminate bronchial secretions. Airways obstruction may result from oedema of the bronchial walls, retained secretious, and in some cases, spasm of bronchial muscles.
Signs and symptoms
Acute infectious bronchitis is often preceded by symptoms of a upper respiratory infection : coryza, malaise, chillness, slight fever, back and muscle pain, and sore throat. On set of cough usually signals onset of bronchitis. The cough is initially dry and non productive, but small amounts of viscid sputum are raised after a few hours or days; it later becomes more abundant and mucoid or mucopurulent.
Frankly purulent sputum suggests superimposed bacterial infection. In severe uncomplicated case, fever to 38.3 or 38.90c (100 or 1020F) ma be present for upto 3 to 5 days, following which acute symptoms subside. Persistent fever suggests complicating pneumonia. Dyspnoea may be noted secondary to the airways obstruction. Pulmonary signs are few in uncomplicated acute bronchitis. Scattered high-or low -pitched rhonchi may be heard, as well as occasional crackling or moist rules at the bases.
Wheezing, specially after cough, is commonly noted. Persistent localised signs suggest development of bronchopneumonia. Serious complications are usually seen only in patients with underlying chronic respiratory disorder. In such patients acute bronchitis may lead to severe blood gas abnormalities.
Doctors may usually make a clinical diagnosis based on symptoms and lack of evidence of pneumonia. Wheezing may be heard during physical examination. On examination of sputum clear or white sputum may suggest viral and yellow or greenish sputum would suggest bacterial infection. On blood examination there will be neutrophil leucositosis. Sutum for Gm. staining and culture may be positive. X-ray chest to be done to exclude other diseases.
Patient should take complete bed rest. Analgescies and steam inhalation be prescribed for some symptomatic relief. To suppress cough at night suppressant cough mixture may be prescribed. Antibiotics of choice such as Amoxicillin and on cephalosponim may be prescribed. For airways obstruction broncho dialators may be prescribed. Inhalors may be used. In emergency or inhalation may be given.
DR. MASWOODUR RAHMAN PRINCE
Similar of Bronchitis