Clinical Knowledge Summaries CKS Chest infections - adults Primary care management of acute bronchitis and community-acquired pneumonia in adults. Infective exacerbations of chronic obstructive pulmonary disease (COPD) are not covered. Educational slides based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009): BTS guidelines for the management of community acquired pneumonia in adults.

Key learning points and objectives To be able to: Distinguish between acute bronchitis and community acquired pneumonia. Outline the management of acute bronchitis and describe when antibiotics should be prescribed. Outline the management of community acquired pneumonia (CAP) and describe which antibiotics should be prescribed. Describe when people with CAP should be admitted or referred for specialist investigation. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Definition Chest infections in primary care can be broadly split into: Acute bronchitis – acute inflammation of the bronchial tree associated with oedema and mucus production leading to cough and phlegm production that lasts for up to 3 weeks. Community acquired pneumonia (CAP) – acute infection of the lung parenchyma. Infective exacerbations of chronic obstructive pulmonary disease (COPD) – discussed in another slide set. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Usual pathogens Acute bronchitis: Community acquired pneumonia (CAP): Viral infections account for most cases, but A significant minority are bacterial e.g. Streptococcus pneumoniae and Haemophilus influenzae. Community acquired pneumonia (CAP): In around 45% of cases no pathogen is found. Streptococcus pneumoniae found in 36%. Haemophilus influenzae found in 10%. Staphylococcus aureus found in 0.8%. Viruses found in 13%. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Prevalence Acute respiratory infections account for 17% of all GP consultations. For acute bronchitis the annual incidence is 44 per 1000 adult population. For CAP: The annual incidence is 5–11 per 1000 adult population. Accounts for 5–12% of all lower respiratory tract infections managed by GPs. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Complications and prognosis Acute bronchitis is usually mild and self-limiting. Cough usually lasts 7–10 days but can last for up to 3 weeks. CAP – complications include: Pleural effusion, empyema, lung abscess, septicaemia and metastatic infection (e.g. meningitis). The mortality associated with pneumonia: Is less than 1% if well enough to be managed in the community. Ranges from 6–12% if hospital admission is required. More than 50% if patient needs intensive care. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Diagnosis Cough is the predominant symptom for acute bronchitis and community-acquired pneumonia (CAP). Difficult to distinguish CAP from acute bronchitis. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Differentiating features Factor Acute bronchitis Community acquired pneumonia History Cough May or may not have sputum, wheeze, or dyspnoea At least one other symptom of sputum, wheeze, dyspnoea, or pleuritic pain Examination Wheeze often present, but no other focal chest signs Focal chest signs present Includes dullness to percussion, course crepitations, vocal fremitus May have systemic features with or without a raised temperature Features include sweats, fevers, myalgia At least one systemic feature present with or without a temperature above 38°C Investigations (not usually considered necessary in general practice) Chest X–ray clear Chest X–ray diagnostic Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Diagnosis No combination of symptoms or signs are clearly diagnostic for CAP. Always use clinical judgement. Elderly people with CAP: Present more frequently with non-specific symptoms, and Are less likely to have a fever (compared with younger people). Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Investigations Chest X-ray Microbiological investigations May not be necessary for people with suspected CAP who are managed in community. Microbiological investigations Usually not necessary to diagnose CAP or acute bronchitis managed in community. Sputum samples for culture and/or sensitivity may be useful in people with: Recurrent episodes of acute bronchitis who may have become colonized with bacteria resistant to first-line antibiotics. Presenter notes Chest X-ray is required : 1) Initially for people with CAP who are managed in the community who are over 50 years of age who smoke. And 2) For people with CAP - at follow up - after 6 weeks for all people: With symptoms and signs that are slow to resolve or persist despite treatment. Who smoke and are over 50 years of age. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Differential diagnosis If acute bronchitis and cough persists longer than 3 weeks rule out: Asthma/chronic obstructive pulmonary disease. Post-infectious cough. Whooping cough. Post-nasal drip. Gastro-oesophageal reflux. Tuberculosis. An underlying malignancy in people who smoke. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Differential diagnosis For people with chest signs, other conditions to rule out include: Pneumonia with underlying malignancy. Heart failure. Pulmonary embolism. Asthma. Based on the CKS topic Chest infections – adults (August 2012).

Acute bronchitis – management

Acute bronchitis – management Adequate analgesia and hydration is all that is usually necessary. Antibiotics are not routinely indicated. If necessary use empirical treatment with: Amoxicillin (first-line), or alternatively Doxycycline. Clarithromycin if amoxicillin or doxycycline is unsuitable. Encourage smoking cessation. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Antibiotics for acute bronchitis? Only prescribe an antibiotic if the person has a pre-existing condition that impairs their ability to deal with infection or is likely to deteriorate with acute bronchitis, for example: Over 75 years of age, with fever. Chronic obstructive pulmonary disease (COPD). Heart failure. Immunocompromised, including people with cancer or insulin dependant diabetes. Give a delayed antibiotic prescription if it is felt safe not to prescribe antibiotics immediately. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Why are antibiotics not usually prescribed for acute bronchitis? Evidence from a Cochrane review shows that: Antibiotics have a modest effect in reducing the duration of cough in some people. Some studies estimate that: The adverse effects of antibiotics are as frequent as beneficial effects. Most experts agree that: Antibiotics are not recommended for people with acute bronchitis who do not have any significant pre-existing conditions. Presenter notes Smith, S.M., Fahey, T., Smucny, J. and Becker, L.A. (2004) Antibiotics for acute bronchitis (Cochrane Review). The Cochrane Library. Issue 4. John Wiley & Sons, Ltd. www.thecochranelibrary.com [Free Full-text]. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Follow up for acute bronchitis Follow up not usually required. Advise the person to seek advice if: Their condition deteriorates significantly, or Symptoms last longer than 3 weeks. People who have deteriorated should be re-examined to exclude pneumonia. For people with a pre-existing condition that has deteriorated on treatment, consider: Admission, or A second-line antibiotic (co-amoxiclav or doxycycline). Seeking advice from a microbiologist if either of these are unsuitable. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Managing community acquired pneumonia (CAP)

Managing CAP – admit or refer? Use the CRB 65 score as well as clinical judgement to help decide if referral or admission is required. Also take social circumstances into account: Does the person live alone? Are they socially isolated? Have a higher index of suspicion in certain groups such as: The elderly, those with rapid deterioration, pre-existing lung conditions. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Using the CRB 65 score When using the CRB 65 score — score one point for each of the following: Confusion — recent. Respiratory rate of 30 breaths/min or greater. Blood pressure — systolic of 90 mmHg or less or diastolic of 60 mmHg or less. 65 years old or older. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Managing CAP — admit or refer? Admit if oxygen saturation is less than 92% (as measured by pulse oximetry). If CRB-65 score is: 3 or 4 — urgently admit to hospital. 2 — refer for same-day assessment (secondary care). 1 — consider same-day assessment (secondary care). 0 — treat at home (depending on clinical judgement and available social support). Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Managing CAP If admission/referral not required: Arrange a chest X-ray for people over 50 years of age who smoke. Advise using analgesia and keeping hydrated. Treat with an antibiotic: Amoxicillin first-line. Erythromycin, clarithromycin, or azithromycin if amoxicillin is contraindicated. Doxycycline can be used if Mycoplasma pneumoniae is suspected. Encourage smoking cessation. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Antibiotics for CAP Immediate empirical treatment with antibiotics is essential to reduce: Mortality, Length of illness, Severity of symptoms, and The likelihood of complications. The trial evidence to support antibiotics is limited, but the benefit of antibiotics is beyond doubt in this group. Placebo controlled trials are considered unethical. Antibiotics may not be appropriate during the terminal phase of life. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Follow up of CAP Follow up all cases of pneumonia. If there is no clinical improvement, or worsening on treatment: Reconsider admission, or Consider a second line antibiotic. If already taking amoxicillin, switch to, or add on, a macrolide (erythromycin or clarithromycin). If these are not suitable, seek advice from a microbiologist. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Follow up of CAP Arrange a chest X-ray after 6 weeks for all people: With symptoms and signs that are slow to resolve or persist despite treatment. Who smoke and are over 50 years of age. Reinforce smoking cessation advice. Once the person has recovered consider pneumococcal and influenza vaccine. Based on the CKS topic Chest infections – adults (August 2012), and guidelines published by the British Thoracic Society (2009); BTS guidelines for the management of community acquired pneumonia in adults.

Summary Difficult to distinguish CAP from acute bronchitis. Viral infections account for most cases. Antibiotics are not usually required – only needed if the person is immunocompromised or has an existing condition likely to significantly worsen. CAP: Use clinical judgement and the CRB 65 score to help decide if referral or admission is required. If managing in community start empirical treatment with an antibiotic. Amoxicillin first-line. Erythromycin, clarithromycin, or azithromycin if amoxicillin is contraindicated. Doxycycline can be used if Mycoplasma pneumoniae is suspected. Arrange chest X-ray after 6 weeks for all people: With symptoms and signs that are slow to resolve or persist despite treatment. Who smoke and are over 50 years of age. Ensure smoking cessation advice is given and reinforced (where appropriate).