Acute Bronchitis Dr. M. A. Sofi MD; FRCP (London); FRCPEdin; FRCSEdin

Acute bronchitis Acute bronchitis, also known as a chest cold, is short-term inflammation of the bronchi (large and medium-sized airways) of the lungs. The most common symptom is a cough. Other symptoms include coughing up mucus, wheezing, shortness of breath, fever, and chest discomfort. The infection may last from a few to ten days. The cough may persist for several weeks afterwards with the total duration of symptoms usually around three weeks. Some have symptoms for up to six weeks.

Bronchitis is characterized by inflammation of the bronchi, the air passages that extend from the trachea into the small airways and alveoli. It is one of the top conditions for which patients seek medical care. Should be distinguished from chronic bronchitis, a condition in patients with COPD distinguished by a cough for at least three months in each of two successive years Acute bronchitis Figure A shows the location of the lungs and bronchial tubes. Figure B is an enlarged view of a normal bronchial tube. Figure C is an enlarged view of a bronchial tube with bronchitis.

In more than 90% of cases the cause is a viral infections Cigarette smoking is indisputably the predominant cause of chronic bronchitis. Most common viruses are: Influenza A and B Parainfluenza Coronavirus (types 1-3) Rhinovirus Respiratory syncytial virus Small number of cases are due to bacteria such Mycoplasma species Chlamydia pneumoniae, Bordetella pertussis. Streptococcus pneumoniae In addition to viruses: Exposure to tobacco smoke Exposure to pollutants or solvents GERD can also cause acute bronchitis. Causes of Bronchitis

Cough (the most commonly observed symptom) Sputum production (clear, yellow, green, or even blood-tinged) Fever (relatively unusual; in conjunction with cough, suggestive of influenza or pneumonia) Nausea, vomiting, and diarrhea (rare) General malaise and chest pain (in severe cases) Dyspnea and cyanosis (only seen with underlying chronic obstructive pulmonary disease [COPD] or another condition that impairs lung function) Sore throat Runny or stuffy nose Headache Muscle aches Extreme fatigue Signs and symptoms

The physical examination findings in acute bronchitis may reveal: Pharyngeal erythema Localized lymphadenopathy Rhinorrhea Coarse rhonchi Wheezes that change in location and intensity after a deep and productive cough. Occasionally, diffuse diminution of air intake Occasionally inspiratory stridor (findings indicate obstruction of a major bronchi or the trachea) Requiring sequentially vigorous coughing, suctioning Possibly, intubation or even tracheostomy. Physical examination findings :

Self-limited inflammation of the bronchi due to upper airway infection, which is most often viral. For most patients with acute bronchitis, the diagnosis is based upon the history and physical examination, and further testing is not needed. Studies that may be helpful include the following: Complete blood count (CBC) with differential Procalcitonin levels (to distinguish bacterial from nonbacterial infections) Sputum cytology (if the cough is persistent) Blood culture (if bacterial super-infection is suspected) Chest radiography (if the patient is elderly or physical findings suggest pneumonia) DIAGNOSIS

Chest x-ray — To exclude pneumonia Abnormal vital signs (pulse >100/minute, Respiratory rate >24 breaths/minute, Temperature >38ºC) Rales or signs of consolidation on chest examination The role of procalcitonin (PCT) in distinguishing patients who would benefit from antibiotic therapy is emerging. PCT is a more specific marker of bacterial infection than white blood count or C- reactive protein Microbiology — Bacterial cultures of expectorated sputum in patients with a negative chest radiograph are not recommended. Influenza should be considered in patients who present with symptoms of acute bronchitis and fever during influenza season Investigations

Chronic bronchitis — Chronic bronchitis, by definition, is diagnosed in patients who have cough and sputum production on most days of the month for at least three months of the year during two consecutive years Pneumonia — Abnormal vital signs (fever, tachypnea, or tachycardia) and signs of consolidation or rales on physical examination suggest the possibility of pneumonia Gastroesophageal reflux — (GERD) is a common cause of intermittent or persistent cough. Cough may be present in the absence of complaints of symptoms of reflux, such as heartburn or sour taste in the mouth. DIFFERENTIAL DIAGNOSIS

Postnasal drip syndrome — The diagnosis of postnasal drip is suggested in patients who describe the sensation of postnasal drainage or the need to frequently clear their throat. Caused by the common cold, allergic rhinitis, vasomotor rhinitis, postinfectious rhinitis, rhinosinusitis, and/or environmental irritants. Asthma — Patients with acute bronchitis often have airway hyperreactivity with changes in pulmonary function testing. In contrast to patients with asthma, airway obstruction is transient in patients with acute bronchitis and usually resolves in five to six weeks. DIFFERENTIAL DIAGNOSIS

Most patients with acute bronchitis require only reassurance and symptomatic treatment. Symptomatic — Many patients with acute bronchitis may benefit from symptomatic treatment using a nonsteroidal anti- inflammatory drug, aspirin, acetaminophen, and/or ipratropium Limit the use of cough suppressants The major therapeutic issue in most cases of acute bronchitis is the decision to use or forgo antibacterial agents. Multiple studies indicate that patients with acute bronchitis do not experience significant benefit from antibiotic therapy TREATMENT

Acute bronchitis should not be treated with antibiotics unless comorbid conditions pose a risk of serious complications Antibiotic therapy is recommended in elderly (>65 years) patients with acute cough if they have had a hospitalization in the past year, have diabetes mellitus or congestive heart failure, or are receiving steroids Antibiotic therapy is recommended in patients with acute exacerbations of chronic bronchitis In stable patients with chronic bronchitis, long-term prophylactic therapy with antibiotics is not indicated. Influenza vaccination may reduce the incidence of upper respiratory tract infections and, subsequently, reduce the incidence of acute bacterial bronchitis. It may be less effective in preventing illness than in preventing serious complications and death. TREATMENT

Limit the use of cough suppressants since mucus should be coughed up to help unblock bronchi. Reduce intake of foods such as sugar, white flour, dairy and others that may be mucus- producing.