Community-acquired pneumonia in children: Outpatient treatment

INTRODUCTION — 

Community-acquired pneumonia (CAP) is defined as an acute infection of the pulmonary parenchyma in a patient who has acquired the infection in the community, as distinguished from hospital-acquired (nosocomial) pneumonia. CAP is a common and potentially serious illness with considerable morbidity.

The outpatient treatment of CAP in infants and children in resource-abundant settings will be reviewed here. Other related topics are discussed separately.

●(See "Neonatal pneumonia".)

●(See "Pneumonia in children: Epidemiology, pathogenesis, and etiology".)

●(See "Community-acquired pneumonia in children: Clinical features and diagnosis".)

●(See "Pneumonia in children: Inpatient treatment".)

INDICATIONS FOR OUTPATIENT MANAGEMENT — 

Most children with mild CAP (eg, low-grade fever, mild or no respiratory distress, normoxia) (table 1) can be managed in the outpatient setting [1-4]. The decision to hospitalize a child with CAP is individualized based on age, underlying medical problems, and clinical factors including severity of illness. Indications for hospitalization are summarized in the table (table 2) and discussed in detail separately. (See "Pneumonia in children: Inpatient treatment", section on 'Hospitalization'.)

BACTERIAL VERSUS VIRAL ETIOLOGY — 

The diagnosis of bacterial versus viral CAP is generally made clinically (table 3). Laboratory tests and chest radiographs are not necessary in children with mild illness. Children with moderate to severe illness are typically hospitalized and undergo additional evaluation. (See "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Clues to etiology' and "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Clinical diagnosis' and "Pneumonia in children: Epidemiology, pathogenesis, and etiology", section on 'Etiologic agents'.)

Children with typical bacterial pneumonia tend to have an abrupt onset of symptoms, which usually include fever, chills, cough, and focal chest pain. These children typically have some degree of respiratory distress with focal lung examination findings and require treatment with antibiotics.

Children with atypical bacterial pneumonia tend to have a gradual onset of fever with headache, malaise, and/or sore throat. Initial symptoms are followed by cough (usually nonproductive) that gradually worsens and is often accompanied by wheezing and/or rales. Fever and illness severity are often milder than with typical bacterial pneumonia. These children also require treatment with antibiotics.

Viral pneumonia is more likely in children <5 years old whose cough develops gradually following an upper respiratory tract infection. Lung findings are diffuse, bilateral, and often include wheezing. These patients should not be treated with antibiotics, but some viral pathogens may require antiviral treatment. The diagnosis of these pathogens is discussed separately. (See "Seasonal influenza in children: Clinical features and diagnosis" and "COVID-19: Clinical manifestations and diagnosis in children" and "Respiratory syncytial virus infection: Clinical features and diagnosis in infants and children".)

The clinical features of bacterial and viral CAP frequently overlap, making it difficult to distinguish between bacterial and viral etiologies. Up to one-half of CAP in children may be a mix of bacterial and viral infections.

Since the introduction of pneumococcal conjugate vaccines (PCVs), the epidemiology of CAP in children has shifted. In a multicenter, prospective, observational study of 2222 children <17 years of age hospitalized for CAP, approximately two-thirds had a viral etiology [5]. Nearly all cases of pneumonia in children <5 years old were caused by a virus. In children ≥5 years old, approximately 20 to 35 percent of cases were caused by an atypical bacterium.

SUPPORTIVE CARE — 

The caregivers of children who are managed as outpatients should be instructed on managing fever and pain, maintaining adequate hydration, and identifying deterioration (eg, increased retractions, use of accessory muscles, grunting, inability to feed) [2].

Children with pneumonia usually have fever and may have pleuritic chest pain, which can lead to shallow breathing and impaired ability to cough [2]. Administration of antipyretics and/or analgesics can be used to keep the child comfortable. Adequate pain control may promote coughing, which facilitates airway clearance. Antitussives should be avoided as none have been found to be effective in pneumonia [6]. Symptomatic treatment of cough is discussed separately. (See "The common cold in children: Management and prevention", section on 'Cough'.)

Infants and young children with respiratory distress may be better able to maintain hydration if fluids are provided in frequent small volumes rather than in less frequent, large volumes.

Gentle suction of the nares may be helpful in infants and children whose nares are blocked by nasal secretions.

PRESUMED BACTERIAL ETIOLOGY

Approach to empiric therapy — Children with CAP who are treated in the outpatient setting typically are treated empirically; tests to identify a bacterial etiology are not recommended for most children who are well enough to be treated in the outpatient setting [1,2]. Evaluation of children with more severe disease is discussed separately. (See "Community-acquired pneumonia in children: Clinical features and diagnosis".)

Once the decision is made to initiate antibiotic therapy, factors that influence the choice of agent include the spectrum of likely pathogens, local antimicrobial susceptibility patterns, regimen simplicity, tolerability, palatability, safety, and cost [7]. The recommendations of most guidelines are based on the antibiotic susceptibility of the most likely pathogen or pathogens rather than on evidence of the superiority of one antibiotic over another [1,2]. The clinical response to the most commonly used antimicrobials appears to be similar, regardless of etiology [8-10].

Consultation with a specialist in infectious diseases may be helpful in children with medication allergies or comorbid conditions.

Neonates — The treatment of neonatal pneumonia is discussed separately. (See "Neonatal pneumonia".)

Children aged 1 to <6 months — Bacterial pneumonia in infants <6 months old usually causes more severe symptoms (table 1), including moderate to severe respiratory distress and/or hypoxia (oxygen saturation <90 percent in room air at sea level). Inpatient management of these patients is generally advised, as discussed separately. (See "Pneumonia in children: Inpatient treatment".)

Occasionally, children aged 1 to <3 months present with milder symptoms and without fever, but bacterial infection is still suspected on the basis of focal lung findings, staccato cough, or tachypnea following an upper respiratory tract infection.

Such afebrile pneumonias are most commonly caused by Chlamydia trachomatis [11,12]. Outpatient management may be attempted, provided that patients are not hypoxic and remain afebrile [12]. Treatment regimens for C. trachomatis are discussed separately. (See "Chlamydia trachomatis infections in newborns and young infants", section on 'Treatment'.)

Children aged six months to <5 years — For most infants ≥6 months old and children <5 years of age, we suggest treatment with high-dose amoxicillin (90 mg/kg per day; maximum dose 4 g per day) given in two to three divided doses (table 4) [1,2,13].

Amoxicillin is preferred because it provides coverage for Streptococcus pneumoniae, the most common bacterial etiology of CAP in this age group (figure 1), and it is well tolerated and inexpensive [1,2,4]. Of note, the detection rate of Mycoplasma pneumoniae in two- to four-year-olds with pneumonia is increasing [5,14] but still remains highest among school-age children and adolescents [15]. For children with clinical features strongly suggestive of atypical bacterial pneumonia, it is reasonable to treat with a macrolide instead of amoxicillin. (See 'Bacterial versus viral etiology' above and 'Children aged ≥5 years' below.)

Standard amoxicillin dosing (35-50 mg/kg per day; maximum dose 4 g per day) administered three times daily could be considered in fully immunized children residing in locales where the prevalence of penicillin-nonsusceptible S. pneumoniae is <10 percent [16,17]. Although we use high-dose amoxicillin, limited clinical trial data suggest that rates of treatment failure may be similar in young children receiving high versus standard amoxicillin dosing for outpatient treatment of CAP [18]. In a multicenter trial (CAP-IT), 814 young children (age >6 months and weight ≤24 kg) diagnosed with CAP who were initially managed in the emergency department, observation unit, or inpatient ward were randomly assigned to receive a standard dose (35 to 50 mg/kg per day) versus a high dose (70 to 90 mg/kg per day) of amoxicillin upon discharge [18]. Both groups had similar rates of treatment failure (12.6 versus 12.4 percent; absolute difference 0.2 percent). Among children with more severe illness, the between-group difference was 3.8 percent (17.3 versus 13.5 percent), but the finding was not statistically significant.

Despite these findings, we continue to use high-dose amoxicillin for patients with CAP. It is likely that many of the children enrolled in CAP-IT had viral rather than bacterial causes for their respiratory symptoms. This may explain the apparent lack of difference between high- versus standard-dose amoxicillin, particularly in milder cases. (See "Resistance of Streptococcus pneumoniae to beta-lactam antibiotics", section on 'Mechanism of action and resistance'.)

Children aged ≥5 years — For most children ≥5 years old, we suggest treatment with a macrolide antibiotic (typically with azithromycin) due to its fewer side effects compared with erythromycin and its convenient dosing schedule (10 mg/kg on day 1 followed by 5 mg/kg daily for four more days; maximum doses: 500 mg on day 1 and 250 mg thereafter) (table 4) [8,19,20]. However, in children whose presentation strongly suggests a typical bacterial pneumonia (eg, abrupt onset of fever, chills, cough, and focal chest pain), amoxicillin is preferred, using the same dosing as for children <5 years of age (table 4). Combination therapy with a macrolide plus amoxicillin or monotherapy with levofloxacin (table 4) is a reasonable alternative option for children whose presentation does not clearly suggest one type of bacterial etiology over the other. (See 'Bacterial versus viral etiology' above and 'Children aged six months to <5 years' above.)

Macrolides provide coverage for M. pneumoniae, the most common cause of bacterial CAP among otherwise healthy children five years and older (figure 1) [5,14]. However, the prevalence of macrolide-resistant M. pneumoniae is increasing in some geographic regions, including the United States, Asia, Europe, and Israel [21-29]. The reported prevalence of macrolide resistance among M. pneumoniae isolates ranges from approximately <10 percent in the United States to 90 percent in China and some parts of Japan [15,23,26,30-32]. If patients treated with a macrolide are not improving as expected, a change in antibiotics may be required. (See 'Monitoring and expected course' below and 'Treatment failure' below.)

We favor amoxicillin over a macrolide for patients with presentations strongly suggestive of typical pneumonia because amoxicillin provides better coverage for S. pneumoniae, the second most common cause of bacterial pneumonia in this age group [1,5]. Additionally, using amoxicillin when M. pneumoniae is less likely decreases macrolide overuse, which is the driver of macrolide-resistant strains.

Special populations

Penicillin allergy — Alternative medications may be appropriate in selected children who have had reactions to penicillin antibiotics. The antibiotic choice is individualized according to the drug allergy history (table 5) and the ability to safely conduct an oral challenge if necessary [33,34]. This is discussed in detail separately. (See "Choice of antibiotics in penicillin-allergic hospitalized patients" and "Penicillin allergy: Immediate reactions" and "Penicillin allergy: Delayed hypersensitivity reactions".)

For children with mild reactions to penicillin and without features of an immunoglobulin E (IgE)-mediated or serious delayed reaction (table 5), amoxicillin is likely safe. An extended-spectrum cephalosporin (eg, cefuroxime axetil, cefpodoxime) is an acceptable alternative in communities with low rates of penicillin-resistant S. pneumoniae isolates [1]. Doses are provided in the table (table 4).

For children with IgE-mediated reactions or serious delayed reactions to penicillin, options include clindamycin, levofloxacin, or linezolid [1,2]. Doses are provided in the table (table 4).

Inability to tolerate oral medications — For the infant or child who is suspected to have bacterial CAP and is unable to tolerate liquids at the time of presentation, a single initial dose of ceftriaxone (50 to 75 mg/kg) may be administered intramuscularly (IM) or intravenously (IV) before starting oral antibiotics [35,36]. Most children will improve sufficiently after a single dose of ceftriaxone to be able to tolerate oral medications. If there is ongoing poor oral intake, hospitalization may be warranted. (See "Pneumonia in children: Inpatient treatment", section on 'Indications'.)

Use of IM or IV ceftriaxone is generally not warranted in children with uncomplicated CAP who are able to tolerate liquids because it is expensive and provides no benefit over oral antibiotics.

Children with swallowing disorders — Aspiration pneumonia acquired in the outpatient setting most commonly occurs in children with swallowing dysfunction due to an underlying neuromuscular or airway disorder. (See "Pneumonia in children: Epidemiology, pathogenesis, and etiology", section on 'Aspiration pneumonia' and "Aspiration due to swallowing dysfunction in children".)

We generally treat these patients with amoxicillin-clavulanate (40 to 50 mg/kg per day of the amoxicillin component divided into two or three doses; maximum dose 1.75 g per day) to provide coverage against the usual bacterial pathogens of CAP and the anaerobes of the oral flora.

Alternative antibiotic choices for patients with IgE-mediated or serious delayed reactions to penicillin (table 5) include clindamycin (for patients of all ages) and moxifloxacin (for adolescents), which are generally effective against anaerobes. Doses are provided in the table (table 4).

Alternative antibiotics with indications for use — The following antibiotics are not routinely used in patients with CAP but may be useful under special circumstances, as discussed below:

●Amoxicillin-clavulanate – High-dose amoxicillin-clavulanate (90 mg/kg per day of the amoxicillin component divided into two or three doses) is a reasonable alternative for unimmunized children aged six months to five years and those with chronic lung disease given the possibility of infection with Haemophilus influenzae and Moxarella catarrhalis in this age group.

●Fluoroquinolones – Fluoroquinolones (eg, levofloxacin, moxifloxacin) (table 4) are active against a number of the pathogens responsible for CAP, including penicillin-susceptible and nonsusceptible S. pneumoniae, beta-lactamase-producing H. influenzae and M. catarrhalis, M. pneumoniae (both azithromycin-susceptible and nonsusceptible strains), and C. pneumoniae [37]. However, S. pneumoniae strains resistant to levofloxacin and moxifloxacin have been identified [15,38].

Although fluoroquinolones are not routine first-line agents for children, they may be reasonable if no other safe and effective alternative is available. A fluoroquinolone could be used if a patient without an obvious CAP complication fails high-dose amoxicillin and/or macrolide therapy. (See "Fluoroquinolones", section on 'Children'.)

●Doxycycline – Doxycycline provides coverage for atypical pathogens, including macrolide-resistant M. pneumoniae [37-39]. It could be used as an alternative therapy for a patient with likely M. pneumoniae pneumonia and no obvious CAP complication who fails macrolide therapy. The long-held concern for enamel staining associated with doxycycline use in children younger than eight years is unfounded [40,41].

Duration of treatment — In most children six months and older who are receiving outpatient treatment for confirmed or suspected bacterial CAP and are clinically improving, we suggest five days of treatment, provided adequate follow-up is in place. If appropriate follow-up is in doubt, treatment should be extended to seven days. The approach to patients who are not improving as expected is discussed below. (See 'Monitoring and expected course' below and 'Treatment failure' below.)

The use of a five-day course of antibiotics to treat nonsevere CAP in the outpatient setting is supported by randomized trials and meta-analyses [18,42-46]. In one meta-analysis of four trials, 1541 children were randomized to receive a shorter course (three to five days) or a longer course (7 to 10 days) of antimicrobial therapy to treat uncomplicated CAP [45]. The rates of antibiotic failure within one month of randomization were similar between groups (7.9 versus 8.0 percent; absolute risk difference 0.1 percent, 95% CI -3.0 to 2.0 percent). Adverse events were also similar and were typically mild (eg, diarrhea, rash). Amoxicillin was the most commonly used antibiotic in the trials, followed by amoxicillin-clavulanate and cefdinir.

Although these results suggest that three to five days of antimicrobial therapy may be sufficient for the outpatient treatment of uncomplicated CAP in resource-abundant settings, we continue to treat for at least five days. The mean age of study participants was <37 months, an age group in which viral pathogens predominate [45]. In the one trial that tested for respiratory viruses, viruses were detected in >80 percent of participants. Consequently, the results of the meta-analysis cannot be generalized to older children, who are more likely to have bacterial pathogens.

The available clinical data in resource-limited settings support <5 days of antibiotic therapy for outpatient treatment of pneumonia [47-49]. However, these data cannot be generalized to resource-abundant settings. In resource-limited settings, pneumonia is typically diagnosed according to World Health Organization criteria using respiratory rate thresholds and clinical findings [50]; many cases may be caused by viral pathogens.

PRESUMED OR CONFIRMED VIRAL ETIOLOGY

Supportive care is the mainstay of management for most viral pneumonia. However, even if a viral etiology is confirmed, ill-appearing patients with an abrupt onset of fever, chills, cough, and focal chest pain may also have a concurrent bacterial infection. In this case, treatment for both would be warranted. (See 'Supportive care' above and 'Bacterial versus viral etiology' above.)

Commonly circulating viruses (table 6) predominate in CAP presenting in early childhood and should not be treated with antibiotics. Antiviral agents are typically not available to treat most viral pneumonia in the outpatient setting either. Although most viral etiologies are treated with supportive care alone, exceptions include influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Antiviral treatment (eg, oseltamivir) should be initiated as soon as possible in children with suspected influenza who are at high risk for complications of influenza pneumonia (table 7). Influenza is suspected when the virus is circulating in the community and the patient has typical symptoms such as fever, headache, sore throat, rhinorrhea, cough, and diffuse myalgia. The diagnosis and management of influenza in children are discussed separately. (See "Seasonal influenza in children: Clinical features and diagnosis" and "Seasonal influenza in children: Management", section on 'Antiviral therapy'.)

Outpatient treatment with an antiviral agent (eg, remdesivir, nirmatrelvir-ritonavir) may be indicated for select children with documented SARS-CoV-2 infection who are at high risk for progression to severe disease. The management of SARS-CoV-2 in children is discussed separately. (See "COVID-19: Management in children".)

Respiratory syncytial virus (RSV), which causes bronchiolitis in children <2 years of age, is primarily treated with supportive care. RSV may be prevented by the administration of immunoprophylaxis to infants. Immunoprophylaxis and the management of RSV bronchiolitis are discussed separately. (See "Respiratory syncytial virus infection: Prevention in infants and children" and "Respiratory syncytial virus infection: Treatment in infants and children" and "Bronchiolitis in infants and children: Treatment, outcome, and prevention".)

MONITORING AND EXPECTED COURSE

We schedule follow-up within 24 to 48 hours for children who are treated for CAP as outpatients (with or without antibiotics) [1,2]. Follow-up may be conducted in the office or performed by phone. Children with uncomplicated CAP whose symptoms are improving do not require follow-up radiographs. This includes children who received radiographs at diagnosis and were found to have round pneumonia (ie, pulmonary consolidation that appears spherical) [51].

Children who are appropriately treated for CAP generally show signs of improvement within 48 to 72 hours and continue to gradually improve with time as follows [52]:

●Children who are recovering from typical or atypical bacterial pneumonia may continue to have a residual cough for several weeks and have moderate dyspnea on exertion for two to three months [52].

●Children who are recovering from viral pneumonia usually have a resolution of their symptoms by one month; rarely, the cough may last for up to three to four months.

Although gradual resolution of bacterial pneumonia symptoms is expected, if cough does not start to improve within two to three weeks of antibiotic completion, we evaluate for treatment failure. (See 'Treatment failure' below.)

Patients whose symptoms completely resolve do not require imaging. Several studies have evaluated the utility of follow-up radiographs in cohorts of children with acute, radiologically proven CAP [53-58]. Three of the studies included clinical and radiologic follow-up at three to seven weeks after initial diagnosis [53-56]. In each of these studies, follow-up radiographs were normal or improved in asymptomatic children. Residual findings, even when present, did not result in additional therapy.

Most otherwise healthy children who develop pneumonia recover without any long-term sequelae [59]. Some prospective studies suggest that pneumonia in childhood is associated with subsequent symptoms of asthma that may persist into adulthood. However, it is not clear whether this is due to unrecognized asthma at the time of pneumonia presentation or a CAP infection predisposing children to develop asthma [60,61].

TREATMENT FAILURE

Lack of improvement — Most children with appropriate management show signs of improvement within 48 to 72 hours, with further gradual improvement in the coming weeks. When patients do not improve as anticipated, the following possibilities must be considered [1,2,62,63]:

●Alternative or coincident diagnoses (eg, foreign body aspiration) (see "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Differential diagnosis')

●Development of complications (see "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Complications')

●Ineffective antibiotic coverage (lack of coverage for the actual etiology or resistant organism)

●Underlying or comorbid conditions (eg, immunodeficiency, anatomic abnormality) (see "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Differential diagnosis')

The history should be reviewed again with special attention to the possibility of foreign body aspiration and geographic or environmental exposures associated with pathogens that were not treated by the empiric regimen (table 8).

In children with persistent symptoms two to three weeks after antibiotic completion, follow-up radiographs may be helpful in assessing alternate diagnoses or coincident conditions [1,2,64]. Other conditions that should be considered if a round opacity is present include congenital lung sequestration, pulmonary arteriovenous malformation, metastatic Wilms tumor, cavitary necrosis, pleural pseudocyst, and primary lung carcinoma [51,64-68]. (See "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Differential diagnosis'.)

In patients who fail to improve but have not worsened, we either add or strengthen coverage for S. pneumoniae or M. pneumoniae if either of these organisms was not covered with the initial therapy [1,12]. Doses are provided in the table (table 4).

●Initial monotherapy with a beta-lactam antibiotic – For most patients who do not improve despite treatment with a beta-lactam antibiotic (amoxicillin, amoxicillin-clavulanate, or cephalosporin) alone, we suggest the addition of a macrolide antibiotic to cover atypical bacteria.

●Initial monotherapy with a macrolide antibiotic – For most patients who do not improve despite treatment with a macrolide antibiotic alone, we suggest obtaining (if available) a throat swab for M. pneumoniae polymerase chain reaction (PCR) testing.

If the M. pneumoniae PCR is positive, the pathogen may be resistant to macrolides. In this case, the macrolide antibiotic should be changed to levofloxacin or doxycycline. (See "Mycoplasma pneumoniae infection in children", section on 'Macrolide resistance'.)

For patients with a negative M. pneumoniae PCR, or if PCR is not available, we suggest adding high-dose amoxicillin to provide better coverage for S. pneumoniae. Although other options include adding high-dose amoxicillin-clavulanate, an extended-spectrum cephalosporin (eg, cefuroxime axetil, cefpodoxime), linezolid, or clindamycin, we prefer high-dose amoxicillin over these options because it is well tolerated and inexpensive.

●Treatment failure while on therapy with a beta-lactam plus a macrolide – For patients who fail to improve while being treated with both a beta-lactam and a macrolide, we suggest changing to clindamycin, linezolid, or a fluoroquinolone (eg, levofloxacin, moxifloxacin).

A lack of response to both a beta-lactam and a macrolide may indicate that the infection is caused by a resistant organism (eg, penicillin-nonsusceptible S. pneumoniae, beta-lactamase-producing H. influenzae, macrolide-resistant M. pneumoniae) or Staphylococcus aureus. A viral etiology is also possible. Clindamycin and linezolid provide coverage for most S. aureus and S. pneumoniae (although resistance of S. aureus to clindamycin should be taken into consideration), while fluoroquinolones provide coverage for penicillin-nonsusceptible S. pneumoniae, H. influenzae, and macrolide-resistant M. pneumoniae.

Worsening condition — Patients who develop worsening signs and symptoms (eg, moderate to severe respiratory distress, hypoxia, toxic appearance, dehydration, or inability to maintain hydration orally) generally require hospitalization. Inpatient management of CAP is discussed separately. (See "Pneumonia in children: Inpatient treatment".)

These patients should also undergo additional evaluation including chest radiographs, laboratory tests, and microbiologic studies. These are discussed in greater detail separately. (See "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Radiographic confirmation' and "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Laboratory evaluation' and "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Approach to microbiologic testing'.)

SOCIETY GUIDELINE LINKS — 

Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Pediatric pneumonia".)

INFORMATION FOR PATIENTS — 

UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient education" and the keyword[s] of interest.)

●Basics topic (see "Patient education: Pneumonia in children (The Basics)")

SUMMARY AND RECOMMENDATIONS

●Definition – Community-acquired pneumonia (CAP) is defined as an acute infection of the pulmonary parenchyma in a patient who has acquired the infection in the community. The clinical manifestations and diagnosis of CAP are discussed separately. (See "Community-acquired pneumonia in children: Clinical features and diagnosis".)

●Outpatient criteria – Most otherwise healthy children ≥6 months old with mild CAP (eg, nontoxic appearance, mild or no respiratory distress, normoxia) (table 1) can be managed in the outpatient setting. Indications for inpatient management are listed in the table (table 2).

●Bacterial versus viral etiology – The diagnosis of bacterial versus viral CAP is generally made clinically (table 3). (See 'Bacterial versus viral etiology' above.)

A typical bacterial etiology (eg, Streptococcus pneumoniae) is more likely if symptoms (which usually include fever, chills, cough, and focal chest pain) start abruptly. These patients typically have some respiratory distress and focal lung examination findings.

An atypical bacterial etiology (eg, Mycoplasma pneumoniae) is more likely if symptom onset (eg, fever, headache, malaise, sore throat) is gradual and followed by cough (usually nonproductive) that gradually worsens and is often accompanied by wheezing and/or rales. Fever and illness severity are often milder than with typical bacterial pneumonia.

A viral etiology is more likely in children <5 years old whose cough develops gradually following an upper respiratory tract infection. Lung findings are diffuse, bilateral, and often include wheezing.

●Presumed bacterial etiology – Outpatient treatment of patients with presumed bacterial CAP is typically empiric. Factors that influence the choice of agent include the likely pathogens, local antimicrobial susceptibility patterns, regimen simplicity, tolerability, palatability, safety, and cost. (See 'Approach to empiric therapy' above.)

•Neonates – The treatment of neonatal pneumonia is discussed separately. (See "Neonatal pneumonia".)

•Age 1 to <6 months – Bacterial pneumonia can cause more severe symptoms in patients <6 months of age than in older children (table 1), and inpatient management is generally advised for these patients. Inpatient management is discussed separately. (See "Pneumonia in children: Inpatient treatment".)

Afebrile patients aged 1 to <3 months who are thought to have afebrile pneumonia of infancy (caused by Chlamydia trachomatis) can be treated in the outpatient setting if they are not hypoxic and remain afebrile. Treatment regimens for C. trachomatis are discussed separately. (See "Chlamydia trachomatis infections in newborns and young infants", section on 'Treatment'.)

•Age six months to <5 years – For most patients ≥6 months and <5 years of age with CAP, we suggest high-dose amoxicillin (90 mg/kg per day given in two to three divided doses; maximum dose 4 g per day) rather than other antibiotics or standard doses of amoxicillin (35 to 50 mg/kg per day) (Grade 2C).

We prefer amoxicillin because it provides coverage for S. pneumoniae, the most common bacterial etiology of CAP in this age group, and it is well tolerated and inexpensive. A macrolide (eg, azithromycin) is a reasonable alternative option in patients with clinical features suggestive of atypical bacterial pneumonia, given that the detection rate of M. pneumoniae is increasing in two- to four-year-olds. (See 'Children aged six months to <5 years' above.)

•Age ≥5 years – For most patients ≥5 years old with CAP, we suggest a macrolide antibiotic (typically, azithromycin 10 mg/kg on day 1 followed by 5 mg/kg daily for four more days; maximum doses: 500 mg on day 1 and 250 mg thereafter) rather than amoxicillin or other antibiotics (Grade 2C). However, in children whose presentation strongly suggests a typical bacterial pneumonia, amoxicillin is preferred (table 4). Combination therapy with a macrolide plus amoxicillin or monotherapy with levofloxacin (table 4) is a reasonable alternative option for children whose presentation does not clearly suggest one type of bacterial etiology over the other.

Macrolides provide coverage for M. pneumoniae, the most common cause of bacterial CAP among otherwise healthy children five years and older (figure 1). Patients should be monitored for treatment failure since the prevalence of macrolide-resistant M. pneumoniae is increasing. (See 'Monitoring and expected course' above and 'Treatment failure' above.)

We favor amoxicillin over a macrolide for patients with presentations strongly suggestive of typical pneumonia because amoxicillin provides better coverage for S. pneumoniae, the second most common cause of bacterial pneumonia in this age group. Additionally, using amoxicillin when M. pneumoniae is less likely to be the pathogen decreases macrolide overuse, which is the driver of macrolide-resistant strains.

Alternative regimens should be used for children with a penicillin allergy. (See 'Penicillin allergy' above.)

●Duration of antimicrobial therapy – A five-day course of antibiotic therapy is sufficient for most patients ≥6 months old with CAP, provided they have adequate follow-up. If appropriate follow-up is in doubt, treatment should be extended to seven days. (See 'Duration of treatment' above.)

●Monitoring clinical response – Children who are treated for CAP as outpatients should have a follow-up visit within 24 to 48 hours. Children who are appropriately treated for CAP generally show signs of improvement within 48 to 72 hours and continue to gradually improve with time. (See 'Monitoring and expected course' above.)

Children with uncomplicated CAP whose symptoms are improving do not require follow-up radiographs.

Most otherwise healthy children who develop pneumonia recover without any long-term sequelae.

●Treatment failure – Patients whose symptoms of CAP have not improved at follow-up should be reevaluated for potential complications. If there are no complications and symptoms have not worsened, adjustment of the antibiotic regimen to strengthen or broaden coverage for S. pneumoniae or M. pneumoniae is appropriate. (See 'Treatment failure' above.)

Patients whose symptoms have worsened at follow-up generally require hospitalization.