child should arouse a strong suspicion of pneumonia Localized findings, more often seen in the child older than year, include inspiratory rales, decreased breath sounds (sometimes the only abnormality), and less often, dullness to percussion Patients with lower lobe pneumonia may present with abdominal pain; occasionally, the abdominal findings in pulmonary infections mimic appendicitis With upper lobe pneumonia, the pain may radiate to the neck, causing meningismus; the diagnosis of pneumonia must, therefore, be considered in the child with nuchal rigidity and normal CSF Triage considerations: Children with fever and respiratory distress should be evaluated for pneumonia, despite the recognition that only a minority of febrile infants and children with respiratory distress will harbor a bacterial pathogen Some children with pneumonia will require supplemental oxygen, more advanced airway support, and/or fluid resuscitation Clinical assessment: The diagnosis often is made by chest radiograph, which can be falsely negative in dehydrated or neutropenic children While there are no pathognomonic findings to differentiate viral from bacterial pneumonia, certain patterns in radiographic findings are of use to the PEM clinician A lobar consolidation is assumed to be of bacterial origin, needing treatment with antibiotics, whereas a minimal, diffuse interstitial infiltrate in a previously healthy toddler suggests a viral infection that can be managed with symptomatic therapy or, in an adolescent, Mycoplasma pneumoniae, calling for treatment with azithromycin Bilateral involvement, pleural effusion, and pneumatoceles indicate more severe disease Further laboratory studies are obtained only on specific indications A WBC count may be helpful in differentiating viral from bacterial disease or in assessing the likelihood of bacteremia in the young child The rate of occult pneumonia in children with leukocytosis >20,000/mm3 remains 10% to 15% in the post-pneumococcal conjugate vaccine era Procalcitonin has been used to stratify the risk of bacterial pneumonia in adults Blood cultures rarely alter management in nontoxic, previously healthy children and are more likely to result in detection of contaminants than pathogens The most common complication of pneumonia is dehydration due to decreased intake and increased insensible losses; this is particularly true for young children Rarely, extensive pulmonary involvement compromises ventilation, leading to respiratory failure ABGs should be considered for any child with significant respiratory distress or transcutaneous oxygen saturation below 90% The most common causes of parapneumonic effusions are pneumococcus and staphylococcus Bacteremia may result in additional foci of infection, including meningitis, pericarditis, epiglottitis, and septic arthritis Management: First, the PEM clinician should consider whether or not the child is a candidate for outpatient therapy ( e-Table 94.7 ) Professional societies have formulated consensus guidelines on which children can be classified as moderate or severe pneumonia and may benefit from intensive care unit care ( e-Table 94.8 ) Second, the PEM clinician needs to consider whether a child requires antibiotic therapy The Infectious Diseases Society of America recommends that antibiotics are not routinely required in preschool-aged children with pneumonia who will be managed as outpatients, as the vast majority have viral etiologies This is a strong recommendation based on high-quality evidence Empiric antibiotic management is reviewed in Table 94.14 Immunocompromised children should receive broad-spectrum antibiotics, including pseudomonal coverage The management of children with complicated pneumonia is described elsewhere in the sections on empyema and lung abscess Standard precautions should be utilized for children with suspected community-acquired pneumonia Other Respiratory Tract Infectious Emergencies Tracheitis Bacterial tracheitis is predominantly caused by S aureus in the post-Hib vaccine era in children without tracheostomies It can mimic the presentation of epiglottitis (see above) with a rapid course While children present with fever and stridor, they are more toxic appearing than children with croup and are in more respiratory distress Radiographs may reveal tracheal narrowing and direct laryngoscopy may demonstrate a pseudomembrane The first step in management is to secure the airway; the emergency medicine physician should anticipate that intubation may be difficult; if anesthesiologist or otolaryngology support is available at a facility, consideration should be given to having them at the bedside prior to intubation being attempted Broad-spectrum antibiotics (e.g., vancomycin and ceftriaxone) should be started and the child should be admitted to an intensive care unit Tracheitis is commonly considered in children with tracheostomies who present with increasing tracheostomy secretions Recognizing that tracheostomy tubes rapidly are colonized with oral and respiratory flora, the diagnosis