Productive cough is the most common presenting symptom [8]. Sputum color is not indicative of bacterial infection and may be clear, yellow, green, or blood-tinged. The cough and the amount of sputum increase as the disease progresses [8]. History from the patient should include information on exposure to toxic substances and smoking habits. Cough characteristics should also be evaluated including frequency, duration, severity, exercise and activity intolerance, and dyspnea [2] [3].

Symptoms of chronic bronchitis include the following [1]:

• Cough
• Sputum production
• Fever
• Nausea, anorexia
• General malaise and fatigue
• Chest pain
• Dyspnea and cyanosis (only seen with underlying chronic obstructive pulmonary disease)

Cyanosis and clubbing are not observed unless the patient has underlying chronic obstructive pulmonary disease or another condition that impairs pulmonary or cardiac function [1]. Fever is a relatively unusual and suggests either influenza or pneumonia [1]. Infections are thought to cause 80% of acute exacerbations [2]. The most common bacterial agents are Haemophilus influenza, Moraxella catarrhalis, and Streptococcus pneumonia [2].

The physical examination findings vary widely depending on the stage of the disease; from coarse rhonchi and wheezes that change in location and intensity after a deep cough to high-pitched continuous diffuse wheezes, inspiratory stridor, diminished air intake and the use of accessory muscles in severe cases [3]. These last findings indicate obstruction of a major bronchi and/or the trachea and require immediate intervention [3].

Acute exacerbations are indicated by increased cough and sputum purulence [9]. Complications include the following [1] [3]:

• Bacterial superinfection
• Pneumonia
• Reactive airway disease 
• Hemoptysis
• COPD
• Congestive heart failure
• Death

Physical examination findings in acute exacerbations of chronic bronchitis vary but may include the [1] [3]:

• Diffuse wheezes, retractions
• Decreased air intake and inspiratory stridor due to bronchial or tracheal obstruction
• Clubbing on the digits and peripheral cyanosis in patients with underlying chronic obstructive pulmonary disease
• Conjunctivitis
• Lymphadenopathy
• Rhinorrhea

Studies that may be helpful include the following [1] [10] [11]:

• Complete blood count (CBC) with differential, procalcitonin levels to distinguish bacterial infections from nonbacterial causes which may reduce antibiotic use [3] [7] 
• Sputum cytology
• Chest radiography
• Pulmonary function testing, spirometry
• PPD to test for tuberculosis
• Influenza A & B tests
• Sputum cultures for influenza virus, Mycoplasma, and Bordetella pertussis [1]
• Blood culture if bacterial superinfection is suspected
• Bronchoscopy to rule out foreign body aspiration, tuberculosis, tumors, and other chronic diseases
• Laryngoscopy

The incidence of infection in acute episodes correlated with changes in the chest radiograph and high levels of C reactive protein (CRP) [6]. An evaluation of procalcitonin (PCT) levels has reduced antibiotic use in patients with acute episodes without increasing the risk for serious adverse outcomes [8]. It has also not increased the rate of adverse outcomes, or antibiotic-associated adverse effects [6] [8]. Spirometry is the gold standard for determining the severity of chronic bronchitis and its progression to COPD [11].

Differential diagnoses [10]:

• Exercise-induced asthma
• Bacterial tracheitis
• Cystic fibrosis
• Influenza
• Hyperreactive airway disease
• Retained foreign body
• Occupational exposures

Treatment for chronic bronchitis is focused on alleviating symptoms and prevention of the progression to COPD, pulmonary hypertension and pulmonary heart disease [1] [5]. The primary interventions are smoking cessation, avoidance of environmental irritants, control of asthma and prevention of respiratory infections [1]. Bronchodilators, expectorants, and cough suppressants in combination are used to open obstructed airways and thin mucous secretions [5]. Further treatments are supportive and include oxygen therapy, proper nutrition, sufficient fluid intake and adequate rest [5].

The best means of controlling cough and mucus production in chronic bronchitis is the avoidance of environmental irritants, especially cigarette smoke [1] [3]. Beyond these measures, care is aimed at ensuring adequate oxygenation, maintaining hydration, and decreasing mucus viscosity [1]. Medications that may be used for the treatment of the symptoms include [5] [12] [13] [14] [15]:

• Central cough suppressants (codeine and dextromethorphan) for short-term symptomatic relief of cough
• Short-acting beta-agonists (ipratropium bromide and theophylline) to control bronchospasm, dyspnea, and chronic cough in stable patients
• Long-acting beta-agonist plus an inhaled corticosteroid for chronic cough
• A short course of systemic corticosteroids to control acute recurrent episodes
• Non-steroidal anti-inflammatory drugs (NSAIDs) for mild-to-moderate pain relief
• Antitussives/expectorants (guaifenesin)
• Mucolytics
• Albuterol to improve air-flow

Bronchitis should not be treated routinely with antibiotics [11]. It is difficult to determine who might benefit from antimicrobial therapy [1] [2] [4]. Clinically, the use of antibiotics has been shown to reduce the number of acute episodes, length of hospitalization, and mortality rates in high-risk patients with chronic bronchitis [2] [12]. Antibiotics reduce the risk of short-term mortality by 77%, decrease the risk of treatment failure by 53% and the risk of sputum purulence by 44% [9]. Antibiotics did not improve arterial blood gases and peak flow [9]. Antibiotic therapy may be recommended in elderly (>65 years) patients with COPD, recent history of hospitalization, diabetes mellitus or congestive heart failure [1] [2]. In stable patients long-term prophylactic therapy with antibiotics is not recommended [2] [12]. Research has found that a short course of antibiotics (5 days) is as effective as the traditional 10 day treatment in patients with mild to moderate exacerbations of chronic bronchitis and COPD [14].

In patients with chronic bronchitis or chronic obstructive pulmonary disease, treatment with mucolytics may reduce the number of acute exacerbations [7] [11]. Mucolytics should be considered in patients with moderate-to-severe COPD, especially in the winter months [4] [7]. Compared with placebo, there was an approximate 20% reduction in the number of exacerbations with oral mucolytics [7]. The number of patients who remained exacerbation-free was greater in the mucolytic group as well [7]. Patients >/= 50 years of age with a diagnosis of chronic bronchitis on maintenance respiratory drugs experienced one or more acute exacerbation per year [10]. Treatment with oral corticosteroids with or without antibiotics reduced this number significantly [10]. Mortality rates were considerably lower in as well [10]. Influenza and pneumococcal pneumonia vaccinations are recommended for all individuals with chronic respiratory disease. This may reduce the incidence of serious complications and death in individuals with chronic bronchitis [15].

Chronic obstructive pulmonary disease, pulmonary heart disease, congestive heart failure and eventual death may result from poorly controlled chronic bronchitis [3]. Reducing the number of exacerbations can reduce personal and healthcare costs associated with the disorder [7].

Chronic bronchitis is a chronic pulmonary disease that affects the upper respiratory airways. It is identified by the presence of a cough with sputum production occurring in at least 3 months in year for 2 or more consecutive years [1] [3].

Chronic obstructive pulmonary disease (COPD) is characterized by progressive airflow obstruction that is only partly reversible, inflammation of the airways, varying degrees of dyspnea [3] [5]. Dyspnea has been defined as a subjective experience associated with the work and effort of breathing [4]. The ability to perform activities of daily living and the time and effort to complete these activities are the base line for measuring the degree of dyspnea [4].

Chronic bronchitis is generally a slowly progressive disease with episodes of acute bronchitis [2]. These exacerbations become more frequent and more severe as the underlying disease advances leading to increased morbidity [2] [3]. The main cause is smoking tobacco, but other factors have been identified, such as allergens, and exposure to environmental pollutants [5]. Most patients have between 1 to 4 acute exacerbations per year [2].The most common risk factors for exacerbation are cigarette smoking, advanced age, and low baseline lung function [2].

It is well-known that chronic bronchitis and COPD usually develop in long-time smokers as they approach middle or old age [2]. These patients, in have decreasing lung function as well as other comorbidities of aging [2] [4]. Occupational exposures associated with the symptoms of chronic bronchitis include coal dust, oil mist, cement, silica, asbestos, welding fumes, organic dusts, engine exhausts, fire smoke, and secondhand cigarette smoke [2] [4].

The mucus-producing layer of the bronchial lining becomes thickened, narrowing the airways so that breathing becomes increasingly difficult [3]. Chronic bronchitis may develop as a series of acute bronchitis episodes or more gradually [2]. Individuals with a history of chronic bronchitis may develop acute episodes of the condition with worsening symptoms and respiratory distress [2]. COPD and emphysema may eventually develop leading eventually to pulmonary heart disease, heart failure and death [2].

Generally, chronic bronchitis is diagnosed by the exclusion of other conditions such as asthma, sinusitis, pharyngitis, tonsillitis, and pneumonia [1] [2]. Allergens and irritants can produce a similar clinical picture. Asthma can be mistakenly diagnosed as episodic bronchitis if the patient has no prior history of asthma [3]. The differentiation is based on the clinical history [3]. Patients with chronic bronchitis have a long history of productive cough and late onset wheezing, while asthma present with initial wheezing and late onset productive cough [2] [5].

Estimates suggest that cigarette smoking accounts for 85-90% of chronic bronchitis and chronic obstructive pulmonary disease cases [4] [5]. Increased respiratory problems have been associated with elevated air pollution. An estimated 50,000 to 120,000 premature deaths are associated with exposure to air pollutants [1]. Bronchitis typically occurs more frequently in the winter months [6]. Over 50% of patients have direct and/or indirect evidence of infection, most commonly bacterial [6].

Smoking is the primary cause of chronic bronchitis accounting for 85-90% of cases [2]. Smoking impairs ciliary movement, inhibits macrophage function, and leads to hypertrophy and hyperplasia of mucus-secreting glands [3]. Smoking also increases airway resistance by stimulating the vagal nerve causing smooth muscle constriction [2]. Hypertrophy of the mucus-producing glands of the mucous lining of the airways of the upper respiratory tract causes the symptoms of chronic bronchitis [1] [3]. Excessive mucous secretions develop, causing the characteristic cough [3]. This abnormality is due to chronic irritation and inflammation of these bronchi from smoking, asthma, or exposure to toxic fumes or particulates [1]. With the inflammation the cilia of the bronchi is destroyed and the bronchociliary function is reduced [3]. Immobilization of the cilia allows foreign substances and irritants to block the bronchial passages making them more susceptible to infection and increased tissue damage [3] [5]. 

The action of interleukin 8, colony-stimulating factors, and other chemotactic and pro-inflammatory cytokines released by damaged bronchial cells result in increased neutrophil production and the fibrotic changes in chronic bronchitis [2]. As the disease progresses the mucous membranes of the airways thicken limiting airflow and causing chronic hypoxia and hypoxemia [3]. Chronic obstructive pulmonary disease and emphysema may develop leading eventually to pulmonary heart disease, heart failure and death [2] [3].

Patients at risk for chronic bronchitis should be advised to:

• Avoid smoking and secondhand smoke.
• Live in a clean environment.
• Receive the influenza vaccine yearly between October and December.
• Receive the pneumonia vaccine every 5-10 years if aged 65 years or older or with chronic disease. 

Chronic bronchitis is a form of pulmonary disease caused by inflammation of the bronchial tubes (bronchi) [1] [2] [3]. These are the air passages of the pulmonary system extending from the trachea to the alveoli. Chronic bronchitis is initially episodic with repeated acute episodes usually triggered by upper respiratory infections, influenza, and exposure to chemical or environmental irritants [2].The symptoms include a persistent productive cough, decreased air-flow, and varying degrees of dyspnea [2] [4]. The severity of symptoms varies depending on the patients underlying respiratory function [5].

The major causes of chronic bronchitis are smoking and exposure to toxic substances or allergens [1] [4]. The first step in dealing with chronic bronchitis is for the patient to stop smoking and avoid respiratory irritants [3]. Treatment is aimed at controlling the cough, decreasing airway obstruction, and reducing mucus production and viscosity [2] [3]. Further therapy is supportive, supplemental oxygen, adequate hydration, and proper nutrition [5].

What is chronic bronchitis?

Chronic bronchitis is a pulmonary disease caused by inflammation of the upper respiratory tract; particularly of the bronchi the air passages the trachea to the lungs. Inflammation is the result of irritation from inhaled toxins such as cigarette smoke, chemical fumes, coal dust, asbestos, or allergens. Chronic bronchitis is characterized by recurrent episodes of acute bronchitis and gradually progressive respiratory disease. It is estimated that 85-90% of cases occur in long-time smokers.

What are the symptoms?

The primary symptoms of chronic bronchitis are a persistent loose cough and excessive mucus production, other symptoms include the following:

• Fever
• Nausea, anorexia
• General malaise and fatigue
• Chest pain
• Dyspnea, respiratory distress

What causes chronic bronchitis?

Chronic bronchitis is caused by repeated irritation of the upper respiratory system. This irritation causes inflammation, swelling, thickening, and narrowing of these airways. The mucus producing glands of the mucus membranes lining the bronchi produce excessive amounts of thick secretions. The inflammation also destroys the cilia, fine hair-like fibers that help to remove the secretions and debris from the respiratory tract. 

Who gets chronic bronchitis?

Chronic bronchitis occurs most frequently in individuals older than 50 years old who are long-time smokers. Other conditions such as chronic asthma, asbestos and toxic chemical exposure, cystic fibrosis, and exposure to coal dust can cause this disorder in individuals of any age.

How is it diagnosed?

Chronic bronchitis is diagnosed initially by clinical presentation; chronic cough with thick mucus production occurring over 3 months for 2 or more years. Definitive diagnosis is made using spirometry, pulmonary function tests and abnormalities seen on chest X-ray.

How is chronic bronchitis treated?

The most important first step is to quit smoking and avoid second-hand tobacco smoke and irritants. Two main types of medications are used to treat chronic bronchitis, bronchodilators and steroids.

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