Atypical pneumonia
- Overview
- Theory
- Diagnosis
- Management
- Follow up
- Resources
Treatment algorithm
Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer
presumed atypical bacterial pneumonia: non-pregnant adult
macrolide
Macrolides cover all common atypical pathogens as well as many of the other causes of community-acquired pneumonia. If the patient is unable to take drugs orally, intravenous formulations are available.
Primary options
azithromycin: 500 mg orally once daily on the first day, followed by 250 mg once daily for 4 days; 500 mg intravenously once daily for at least 5 days
OR
clarithromycin: 500 mg orally (immediate-release) twice daily for 14-21 days
OR
erythromycin base: 500 mg orally four times daily for 14-21 days; 1000 mg intravenously four times daily for 14-21 days
supportive care
Treatment recommended for ALL patients in selected patient group
Patients should be assessed for hydration status, haemodynamic stability, and adequacy of gas exchange. Oxygen and ventilation should be started immediately if needed.
How to insert a tracheal tube in an adult using a laryngoscope.
How to use bag-valve-mask apparatus to deliver ventilatory support to adults. Video demonstrates the two-person technique.
[

doxycycline
Doxycycline covers common atypical pathogens as well as many of the other causes of community-acquired pneumonia. It is considered to be the first-line treatment for less common zoonotic atypical pathogens, such as Chlamydophila psittaci (psittacosis) and Coxiella burnetii (Q fever).
Primary options
doxycycline: 100 mg orally twice daily for 14 days
supportive care
Treatment recommended for ALL patients in selected patient group
Patients should be assessed for hydration status, haemodynamic stability, and adequacy of gas exchange. Oxygen and ventilation should be started immediately if needed.
How to insert a tracheal tube in an adult using a laryngoscope.
How to use bag-valve-mask apparatus to deliver ventilatory support to adults. Video demonstrates the two-person technique.
[

fluoroquinolone
These agents provide coverage for all atypical pathogens, although less evidence exists for Chlamydophila species. They are the drug of choice for patients with comorbidities such as diabetes, alcoholism, chronic heart, lung, liver, or renal disease.
These agents can be given orally or intravenously and they generally provide broader spectrum coverage than is needed for atypical bacterial pneumonia.
Their use may promote emergence of fluoroquinolone resistance, and so widespread use in the community is discouraged.[18]Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019 Oct 1;200(7):e45-67. https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST http://www.ncbi.nlm.nih.gov/pubmed/31573350?tool=bestpractice.com
Systemic fluoroquinolone antibiotics may cause serious, disabling, and potentially long-lasting or irreversible adverse events. This includes, but is not limited to, tendinopathy/tendon rupture; peripheral neuropathy; arthropathy/arthralgia; aortic aneurysm and dissection; heart valve regurgitation; dysglycaemia; and central nervous system effects including seizures, depression, psychosis, and suicidal thoughts and behaviour.[79]Rusu A, Munteanu AC, Arbănași EM, et al. Overview of side-effects of antibacterial fluoroquinolones: new drugs versus old drugs, a step forward in the safety profile? Pharmaceutics. 2023 Mar 1;15(3):804. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10056716 http://www.ncbi.nlm.nih.gov/pubmed/36986665?tool=bestpractice.com Prescribing restrictions apply to the use of fluoroquinolones, and these restrictions may vary between countries. In general, fluoroquinolones should be restricted for use in serious, life-threatening bacterial infections only. Some regulatory agencies may also recommend that they must only be used in situations where other antibiotics, that are commonly recommended for the infection, are inappropriate (e.g., resistance, contraindications, treatment failure, unavailability). Consult your local guidelines and drug formulary for more information on suitability, contraindications, and precautions.
Primary options
levofloxacin: 750 mg orally/intravenously once daily for 5 days
OR
moxifloxacin: 400 mg orally/intravenously once daily for 7-14 days
supportive care
Treatment recommended for ALL patients in selected patient group
Patients should be assessed for hydration status, haemodynamic stability, and adequacy of gas exchange. Oxygen and ventilation should be started immediately if needed.
How to insert a tracheal tube in an adult using a laryngoscope.
How to use bag-valve-mask apparatus to deliver ventilatory support to adults. Video demonstrates the two-person technique.
[

beta-lactam antibiotic plus hospitalisation
Treatment recommended for ALL patients in selected patient group
In severe community-acquired pneumonia, guidelines recommend empirical treatment with a beta-lactam antibiotic, as well as coverage for atypical pathogens.[18]Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019 Oct 1;200(7):e45-67. https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST http://www.ncbi.nlm.nih.gov/pubmed/31573350?tool=bestpractice.com [41]Lim WS, Baudouin SV, George RC, et al; Pneumonia Guidelines Committee of the BTS Standards of Care Committee. BTS guidelines for the management of community acquired pneumonia in adults: update 2009. Thorax. 2009 Oct;64 Suppl 3:iii1-55. https://thorax.bmj.com/content/64/Suppl_3/iii1.long http://www.ncbi.nlm.nih.gov/pubmed/19783532?tool=bestpractice.com Antibiotic treatment should be directed at the causative organism once aetiology is established. Consult local guidelines for guidance on antibiotic regimen selection and doses.
corticosteroid
Additional treatment recommended for SOME patients in selected patient group
The use of corticosteroids in patients with severe community-acquired pneumonia has been a long-debated issue. Current guidelines generally recommend against the use of corticosteroids in patients with non-severe community-acquired pneumonia. This recommendation is based on the fact that there are no data suggesting benefit in patients with non-severe community-acquired pneumonia, or influenza pneumonia, with respect to mortality or organ failure, and only limited data to support their use in patients with severe community-acquired pneumonia.[18]Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019 Oct 1;200(7):e45-67. https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST http://www.ncbi.nlm.nih.gov/pubmed/31573350?tool=bestpractice.com However, Surviving Sepsis Campaign guidelines acknowledge that they may be considered in patients with refractory septic shock and an ongoing requirement for vasopressor therapy.[69]Evans L, Rhodes A, Alhazzani W, et al. Surviving sepsis campaign: international guidelines for management of sepsis and septic shock 2021. Crit Care Med. 2021;49(11):e1063-e1143 https://journals.lww.com/ccmjournal/Fulltext/2021/11000/Surviving_Sepsis_Campaign__International.21.aspx http://www.ncbi.nlm.nih.gov/pubmed/34605781?tool=bestpractice.com
A study from Japan suggests that corticosteroids may not offer any advantage in the treatment of M pneumoniae pneumonia.[77]Okubo Y, Michihata N, Morisaki N, et al. Recent trends in practice patterns and impact of corticosteroid use on pediatric Mycoplasma pneumoniae-related respiratory infections. Respir Investig. 2018 Mar;56(2):158-65. http://www.ncbi.nlm.nih.gov/pubmed/29548654?tool=bestpractice.com However, adjunct corticosteroid therapy has been found to significantly reduce the duration of fever, length of hospital stay, and decreased CRP levels in patients with macrolide-refractory M pneumoniae.[78]Kim HS, Sol IS, Li D, et al. Efficacy of glucocorticoids for the treatment of macrolide refractory mycoplasma pneumonia in children: meta-analysis of randomized controlled trials. BMC Pulm Med. 2019 Dec 18;19(1):251. https://www.doi.org/10.1186/s12890-019-0990-8 http://www.ncbi.nlm.nih.gov/pubmed/31852460?tool=bestpractice.com
presumed atypical bacterial pneumonia: pregnant or child
macrolide
Macrolides cover all common atypical pathogens as well as many of the other causes of community-acquired pneumonia.
If the patient is unable to take drugs orally, intravenous formulations of erythromycin and azithromycin are available; however, the patient should be switched to oral therapy when possible.
Treatment course: 5 days (azithromycin); 14-21 days (erythromycin, clarithromycin).
Primary options
azithromycin: children ≥3 months of age: 10 mg/kg orally once daily on day 1, followed by 5 mg/kg once daily on days 2-5, maximum 500 mg/day; adults: 500 mg intravenously/orally once daily on day 1, followed by 500 mg intravenously once daily or 250 mg orally once daily on days 2-5
OR
erythromycin lactobionate: children and adults: 20 mg/kg/day intravenously given in divided doses every 6 hours, maximum 4000 mg/day
OR
erythromycin base: children: 40 mg/kg/day orally given in 4 divided doses, maximum 2000 mg/day; adults: 500 mg orally four times daily
OR
clarithromycin: children ≥3 months of age: 7.5 mg/kg orally twice daily, maximum 1000 mg/day; adults: 500 mg orally (immediate-release) twice daily
supportive care
Treatment recommended for ALL patients in selected patient group
Patients should be assessed for hydration status, haemodynamic stability, and adequacy of gas exchange. Oxygen and ventilation should be started immediately if needed.
How to insert a tracheal tube in an adult using a laryngoscope.
How to use bag-valve-mask apparatus to deliver ventilatory support to adults. Video demonstrates the two-person technique.
[

fluoroquinolone
Consult a specialist for guidance if an alternative treatment option is required.
If a patient has a macrolide resistant Mycoplasma pneumoniae infection, a fluoroquinolone may be considered as an alternative treatment, provided the benefits outweigh the risks, and there are no other appropriate treatment options available. Fluoroquinolones should not be used in pregnancy unless the potential benefits outweigh the risks.
Patients should be switched to oral therapy when possible to complete the treatment course.
Systemic fluoroquinolone antibiotics may cause serious, disabling, and potentially long-lasting or irreversible adverse events. This includes, but is not limited to, tendinopathy/tendon rupture; peripheral neuropathy; arthropathy/arthralgia; aortic aneurysm and dissection; heart valve regurgitation; dysglycaemia; and central nervous system effects including seizures, depression, psychosis, and suicidal thoughts and behaviour.[79]Rusu A, Munteanu AC, Arbănași EM, et al. Overview of side-effects of antibacterial fluoroquinolones: new drugs versus old drugs, a step forward in the safety profile? Pharmaceutics. 2023 Mar 1;15(3):804. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10056716 http://www.ncbi.nlm.nih.gov/pubmed/36986665?tool=bestpractice.com Prescribing restrictions apply to the use of fluoroquinolones, and these restrictions may vary between countries. In general, fluoroquinolones should be restricted for use in serious, life-threatening bacterial infections only. Some regulatory agencies may also recommend that they must only be used in situations where other antibiotics, that are commonly recommended for the infection, are inappropriate (e.g., resistance, contraindications, treatment failure, unavailability). Consult your local guidelines and drug formulary for more information on suitability, contraindications, and precautions.
Primary options
levofloxacin: children ≥6 months to 4 years of age: 8-10 mg/kg intravenously every 12 hours, maximum 750 mg/day; children ≥5 years of age: 8-10 mg/kg/day intravenously every 24 hours, maximum 750 mg/day
supportive care
Treatment recommended for ALL patients in selected patient group
Patients should be assessed for hydration status, haemodynamic stability, and adequacy of gas exchange. Oxygen and ventilation should be started immediately if needed.
How to insert a tracheal tube in an adult using a laryngoscope.
How to use bag-valve-mask apparatus to deliver ventilatory support to adults. Video demonstrates the two-person technique.
[

beta-lactam antibiotic plus hospitalisation
Treatment recommended for ALL patients in selected patient group
In severe community-acquired pneumonia, guidelines recommend empirical treatment with a beta-lactam antibiotic, as well as coverage for atypical pathogens.[18]Metlay JP, Waterer GW, Long AC, et al. Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med. 2019 Oct 1;200(7):e45-67. https://www.atsjournals.org/doi/full/10.1164/rccm.201908-1581ST http://www.ncbi.nlm.nih.gov/pubmed/31573350?tool=bestpractice.com [41]Lim WS, Baudouin SV, George RC, et al; Pneumonia Guidelines Committee of the BTS Standards of Care Committee. BTS guidelines for the management of community acquired pneumonia in adults: update 2009. Thorax. 2009 Oct;64 Suppl 3:iii1-55. https://thorax.bmj.com/content/64/Suppl_3/iii1.long http://www.ncbi.nlm.nih.gov/pubmed/19783532?tool=bestpractice.com Antibiotic treatment should be directed at the causative organism once etiology is established. Consult local guidelines for guidance on antibiotic regimen selection and doses.
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Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups. See disclaimer
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