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Acute Bronchitis

By

Sanjay Sethi

, MD, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences

Reviewed/Revised May 2023
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Acute bronchitis is inflammation of the tracheobronchial tree, commonly following an upper respiratory infection in the absence of chronic lung disorders. The cause is almost always a viral infection. The pathogen is rarely identified. The most common symptom is cough, with or without fever, and possibly sputum production. Diagnosis is based on clinical findings. Treatment is supportive; antibiotics are usually unnecessary. Prognosis is excellent.

Acute bronchitis is frequently a component of an upper respiratory infection (URI) caused by rhinovirus Common Cold The common cold is an acute, usually afebrile, self-limited viral infection causing upper respiratory symptoms, such as rhinorrhea, cough, and sore throat. Diagnosis is clinical. Handwashing... read more , parainfluenza Parainfluenza Virus Infections Parainfluenza viruses include several closely related viruses that cause many respiratory illnesses varying from the common cold to an influenza-like syndrome or pneumonia; croup is the most... read more , influenza A or B virus Influenza Influenza is a viral respiratory infection causing fever, coryza, cough, headache, and malaise. Mortality is possible during seasonal epidemics, particularly among high-risk patients (eg, those... read more , respiratory syncytial virus Respiratory Syncytial Virus (RSV) and Human Metapneumovirus Infections Respiratory syncytial virus and human metapneumovirus infections cause seasonal lower respiratory tract disease, particularly in infants and young children. Disease may be asymptomatic, mild... read more , coronavirus Coronaviruses and Acute Respiratory Syndromes (MERS and SARS) Coronaviruses are enveloped RNA viruses that cause respiratory illnesses of varying severity from the common cold to fatal pneumonia. Numerous coronaviruses, first discovered in domestic poultry... read more , or human metapneumovirus Respiratory Syncytial Virus (RSV) and Human Metapneumovirus Infections Respiratory syncytial virus and human metapneumovirus infections cause seasonal lower respiratory tract disease, particularly in infants and young children. Disease may be asymptomatic, mild... read more . Bacteria, such as Mycoplasma pneumoniae Mycoplasmas Mycoplasmas are ubiquitous bacteria that differ from other prokaryotes in that they lack a cell wall. Mycoplasma pneumoniae is a common cause of pneumonia, particularly community-acquired... read more , Bordetella pertussis Pertussis Pertussis is a highly communicable disease occurring mostly in children and adolescents and caused by the gram-negative bacterium Bordetella pertussis. Symptoms are initially those of... read more , and Chlamydia pneumoniae Chlamydia pneumoniae Three species of Chlamydia cause human disease, including sexually transmitted infections and respiratory infections. Diagnosis depends on species; culture, nucleic acid amplification... read more , cause less than 5% of cases; these sometimes occur in outbreaks. Acute bronchitis is part of the spectrum of illness that occurs with SARS-CoV-2 infection, and testing for this virus is appropriate. Fever, myalgias, sore throat, gastrointestinal symptoms, and loss of smell and taste are more common with the SARS-CoV-2 virus than others.

Pearls & Pitfalls

  • Acute cough in patients with asthma, COPD, bronchiectasis, or cystic fibrosis should typically be considered an exacerbation of that disorder rather than simple acute bronchitis.

Symptoms and Signs of Acute Bronchitis

Symptoms are a nonproductive or mildly productive cough accompanied or preceded by URI symptoms. Typical symptom duration before presentation is about 5 days or more. Subjective dyspnea results from chest pain caused by musculoskeletal discomfort due to coughing or chest tightness related to bronchospasm, not from hypoxia.

On resolution, cough is the last symptom to subside and often takes 2 to 3 weeks or even longer to do so.

Diagnosis of Acute Bronchitis

  • Clinical evaluation

  • Sometimes chest x-ray to exclude other disorders

Diagnosis is based on clinical presentation. Microbiologic testing is usually unnecessary. However, patients with signs or symptoms of COVID-19 should be tested for SARS-CoV-2. Diagnostic testing for influenza and pertussis should also be considered if there is high clinical suspicion based on exposure and/or clinical features.

Patients who complain of dyspnea should have pulse oximetry to rule out hypoxemia.

Chest x-ray is done if findings suggest serious illness or pneumonia Community-Acquired Pneumonia Community-acquired pneumonia is defined as pneumonia that is acquired outside the hospital. The most commonly identified pathogens are Streptococcus pneumoniae, Haemophilus influenzae... read more Community-Acquired Pneumonia (eg, ill appearance, mental status change, high fever, tachypnea, hypoxemia, crackles, signs of consolidation or pleural effusion). Older patients are the occasional exception, because they may have pneumonia without fever and auscultatory findings, presenting instead with altered mental status and tachypnea.

Sputum Gram stain and culture usually have no role. Nasopharyngeal samples can be tested for influenza and pertussis Diagnosis Pertussis is a highly communicable disease occurring mostly in children and adolescents and caused by the gram-negative bacterium Bordetella pertussis. Symptoms are initially those of... read more if these disorders are clinically suspected (eg, for pertussis, persistent and paroxysmal cough after 10 to 14 days of illness, only sometimes with the characteristic whoop and/or retching, exposure to a confirmed case). Testing for Mycoplasma and Chlamydia infection does not affect treatment so is not recommended. Viral panel testing is not usually recommended because results do not affect treatment.

Cough resolves within 2 weeks in 75% of patients; in the other 25%, it may take up to 8 weeks to resolve. Patients with cough that worsens after initial improvement and those with cough that lingers for > 8 weeks should undergo further evaluation, including a chest x-ray. Evaluation for noninfectious causes of chronic cough, including asthma, postnasal drip, and gastroesophageal reflux disease Gastroesophageal Reflux Disease (GERD) Incompetence of the lower esophageal sphincter allows reflux of gastric contents into the esophagus, causing burning pain. Prolonged reflux may lead to esophagitis, stricture, and rarely metaplasia... read more Gastroesophageal Reflux Disease (GERD) , can usually be made on the basis of the clinical presentation. Differentiation of cough-variant asthma Asthma Asthma is a disease of diffuse airway inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. Symptoms and signs include dyspnea... read more may require pulmonary function testing.

Treatment of Acute Bronchitis

  • Symptom relief (eg, acetaminophen, hydration, possibly antitussives)

  • Inhaled beta-agonist for wheezing

Acute bronchitis in otherwise healthy patients is a major cause of antibiotic overuse. Nearly all patients require only symptomatic treatment, such as acetaminophen and hydration. Evidence supporting efficacy of routine use of other symptomatic treatments, such as antitussives, mucolytics, and bronchodilators, is weak. Antitussives Treatment should be considered only if the cough is distressing or interfering with sleep. Patients with wheezing may benefit from an inhaled beta2-agonist (eg, albuterol) for a few days. Broader use of beta2-agonists is not recommended because adverse effects such as tremor, nervousness, and shaking are common. There are no clear indications for mucolytics.

Though some studies have shown modest symptomatic benefits with antibiotic use in acute bronchitis, the low incidence of bacterial causation, self-limiting nature of acute bronchitis, and the risk of adverse effects and antibiotic resistance Antibiotic Resistance Antibacterial drugs are derived from bacteria or molds or are synthesized de novo. Technically, “antibiotic” refers only to antimicrobials derived from bacteria or molds but is often (including... read more Antibiotic Resistance argue against widespread antibiotic use. Patient education and delayed prescription (ie, to be only filled if no improvement after at least a couple of days) help limit unnecessary antibiotic use. Oral antibiotics are typically not used except in patients with pertussis Pertussis Pertussis is a highly communicable disease occurring mostly in children and adolescents and caused by the gram-negative bacterium Bordetella pertussis. Symptoms are initially those of... read more or during known outbreaks of bacterial infection (mycoplasma, chlamydia). A macrolide such as azithromycin 500 mg orally once, then 250 mg orally once a day for 4 days or clarithromycin 500 mg orally twice a day for 7 days is the preferred choice.

Pearls & Pitfalls

  • Treat most cases of acute bronchitis in healthy patients without using antibiotics.

Key Points

  • Acute bronchitis is viral in > 95% of cases, often part of an upper respiratory infection.

  • Diagnose acute bronchitis mainly by clinical evaluation; do chest x-ray and/or other tests only in patients who have manifestations of more serious illness.

  • Treat most patients only to relieve symptoms.

Drugs Mentioned In This Article

Drug Name Select Trade
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Accuneb, ProAir digihaler, Proair HFA, ProAir RespiClick, Proventil, Proventil HFA, Proventil Repetabs, Respirol , Ventolin, Ventolin HFA, Ventolin Syrup, Volmax, VoSpire ER
Azasite, Zithromax, Zithromax Powder, Zithromax Single-Dose , Zithromax Tri-Pak, Zithromax Z-Pak, Zmax, Zmax Pediatric
Biaxin, Biaxin XL
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NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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