brand logo

Am Fam Physician. 2021;104(6):618-625

This clinical content conforms to AAFP criteria for CME.

Author disclosure: No relevant financial affiliations.

In the United States, pneumonia is the most common cause of hospitalization in children. Even in hospitalized children, community-acquired pneumonia is most likely of viral etiology, with respiratory syncytial virus being the most common pathogen, especially in children younger than two years. Typical presenting signs and symptoms include tachypnea, cough, fever, and anorexia. Findings most strongly associated with an infiltrate on chest radiography in children with clinically suspected pneumonia are grunting, history of fever, retractions, crackles, tachypnea, and the overall clinical impression. Chest radiography should be ordered if the diagnosis is uncertain, if patients have hypoxemia or significant respiratory distress, or if patients fail to show clinical improvement within 48 to 72 hours after initiation of antibiotic therapy. Outpatient management of community-acquired pneumonia is appropriate in patients without respiratory distress who can tolerate oral antibiotics. Amoxicillin is the first-line antibiotic with coverage for Streptococcus pneumoniae for school-aged children, and treatment should not exceed seven days. Patients requiring hospitalization and empiric parenteral therapy should be transitioned to oral antibiotics once they are clinically improving and able to tolerate oral intake. Childhood and maternal immunizations against S. pneumoniae, Haemophilus influenzae type b, Bordetella pertussis, and influenza virus are the key to prevention.

Community-acquired pneumonia (CAP) is a lung infection contracted outside of the hospital. Lower respiratory tract infection includes pneumonia, bronchitis, bronchiolitis, or any combination of the three. In the United States, pneumonia is the most common cause of hospitalization in children.1

RecommendationSponsoring organization
Do not use broad-spectrum antibiotics such as ceftriaxone for children hospitalized with uncomplicated community-acquired pneumonia; use narrow-spectrum antibiotics such as penicillin, ampicillin, or amoxicillin.Society of Hospital Medicine, American Academy of Pediatrics, Academic Pediatric Association
Do not prescribe intravenous antibiotics for predetermined durations for patients hospitalized with infections such as pyelonephritis, osteomyelitis, and complicated pneumonia; consider early transition to oral antibiotics.Society of Hospital Medicine, American Academy of Pediatrics, Academic Pediatric Association
Do not routinely use airway clearance therapy in conditions such as asthma, bronchiolitis, and pneumonia.American Academy of Pediatrics—Section on Pediatric Pulmonology and Sleep Medicine


  • In a U.S. population of 2,638 patients younger than 18 years hospitalized with CAP, a viral pathogen was more likely than a bacterial pathogen (66% compared with 8%, respectively; 7% of patients had both viral and bacterial pathogens; no pathogen was identified in 19%).2

  • Respiratory syncytial virus is the most common pathogen overall, particularly in children younger than two years.2

  • Other common respiratory viruses include influenza virus, coronavirus (including SARS-CoV-2, which causes COVID-19), human rhinovirus, human metapneumovirus, and adenovirus.2

  • Due to routine childhood vaccinations, the prevalence of Streptococcus pneumoniae and Haemophilus influenzae has decreased significantly. In the United States, the introduction of the pneumococcal conjugate vaccine resulted in a reduction in hospitalizations for pneumococcal pneumonia from 53.6 to 23.3 per 100,000 admissions from 2006 to 2014.3

  • Table 1 shows the specific etiology in hospitalized children with pneumonia based on the Centers for Disease Control and Prevention's Etiology of Pneumonia in the Community study, a multicenter, population-based, prospective study conducted from 2010 to 2012.2

PathogenYounger than 2 years2 to 4 years5 to 9 years10 to 17 years
Human metapneumovirus14%17%10%4%
Human rhinovirus29%25%30%19%
Influenza A/B6%5%9%11%
Parainfluenza virus 1 to 37%8%6%4%
Respiratory syncytial virus42%29%8%7%
Mycoplasma pneumoniae2%5%16%23%
Staphylococcus aureus1%1%1%1%
Streptococcus pneumoniae3%4%4%3%
Streptococcus pyogenes1%1%< 1%< 1%



  • Typical presenting signs and symptoms include tachypnea, cough, fever, anorexia, dyspnea, retractions, and lethargy.2,4,5

  • In a series of 570 children one to 17 years of age with clinically suspected pneumonia, findings most strongly associated with an infiltrate on chest radiography were grunting (odds ratio [OR] = 7.3), history of fever (OR = 3.1), retractions (OR = 2.8), and crackles (OR = 2.0).6 Other findings associated with infiltrate included measured fever, tachypnea, tachycardia, and decreased breath sounds. Although grunting and retractions are uncommon, when present they have a high positive predictive value for pneumonia.6

  • Based on a systematic review of three studies, the overall clinical impression is moderately accurate for diagnosing CAP in children (positive likelihood ratio = 2.7; negative likelihood ratio = 0.63).7

  • Wheezing, retractions, and respiratory rate are the examination findings with the highest interrater reliability in children with CAP.8


  • Clinical prediction rules have been studied but have not been prospectively validated, particularly in primary care settings.6,9,10

  • The Bilkis Simpler Prediction Model has high sensitivity (93.8%) for the diagnosis of pneumonia in children presenting with any combination of fever, localized rales, decreased breath sounds, and tachypnea.9 A similar model also had excellent sensitivity (93% to 98%) but poor specificity (6% to 19%), making it unhelpful in clinical practice.6

  • The Pediatric Acute Febrile Respiratory Illness rule assigns points for duration of fever, chills, absence of nasal symptoms, tachypnea, and abnormal chest examination. Once prospectively validated in a new population, it may help clinicians to decide which children should have chest radiography.10


  • Chest radiography is not necessary to confirm suspected pneumonia in children in the outpatient setting. It should be obtained for patients with hypoxemia (oxygen saturation less than 90%) or significant respiratory distress or for those without clinical improvement within 48 to 72 hours after initiation of antibiotic therapy.11 Figure 1 shows a chest radiograph demonstrating a left upper-lobe opacity consistent with pneumonia.

  • Chest ultrasonography is more often used to evaluate local complications such as parapneumonic effusion or empyema, but it may also detect lung consolidation and save time and cost.12,13 Novice and expert physician-sonologists have achieved a reduction of chest radiography use in emergency department settings without missed cases of pneumonia or an increase in adverse events.14

  • Procalcitonin may be used in conjunction with other clinical findings to guide the management of pneumonia in children. Values less than 0.25 ng per mL can accurately identify children at lower risk of bacterial CAP for whom antibiotics are unlikely to be helpful.15,16

  • Complete blood count and levels of acute-phase reactants such as erythrocyte sedimentation rate and C-reactive protein are not typically obtained in the outpatient setting. However, they may be beneficial for management decisions in more severely ill children in the hospital setting, according to Infectious Diseases Society of America (IDSA) guidelines.11 Measurement of C-reactive protein in general practice settings for children with nonsevere acute infections has not been shown to reduce antibiotic prescribing and is not recommended.17

  • Blood cultures should not be performed routinely in nontoxic, fully immunized children in the outpatient setting.11 Blood cultures should be obtained in hospitalized patients, but even in this setting, a pathogen is identified in only 2% to 7% of children with CAP.11,18

  • Sputum cultures are difficult to obtain in children and have low diagnostic yield.11

  • Physicians should have appropriate suspicion and consider testing for COVID-19, influenza, respiratory syncytial virus, or Mycoplasma pneumoniae as indicated.11,19,20

Already a member/subscriber?  Log In


From $145
  • Immediate, unlimited access to all AFP content
  • More than 130 CME credits/year
  • AAFP app access
  • Print delivery available

Issue Access

  • Immediate, unlimited access to this issue's content
  • CME credits
  • AAFP app access
  • Print delivery available

Article Only

  • Immediate, unlimited access to just this article
  • CME credits
  • AAFP app access
  • Print delivery available
Purchase Access:  Learn More

Continue Reading

More in AFP

More in Pubmed

Copyright © 2021 by the American Academy of Family Physicians.

This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP.  See permissions for copyright questions and/or permission requests.