Management: If the node is fluctuant, aspiration provides useful etiologic information and speeds the rate of resolution Children who fail to respond to empiric antibiotic therapy and children with tuberculosis risk factors who present with adenitis should have a TST placed Children with cervical adenitis who are otherwise healthy should receive an antibiotic effective against S aureus and the GAS While clindamycin (10 mg/kg/dose three times daily; maximum: 600 mg/dose) has activity against both pathogens, trimethoprim-sulfamethoxazole (TMPSMZ) will not offer GAS coverage The decision about which oral antibiotic to select depends on the level of methicillin-resistant S aureus (MRSA) in a community Indications for inpatient admission and parenteral antibiotics include: toxic appearance; young age (27 kg: 1.2 million units) Regimens for penicillin-allergic patients include cephalosporins and macrolides There are no data suggesting that the use of cephalosporins decreases the risk of relapse or leads to symptoms resolution faster than more narrow-spectrum antibiotics Amoxicillinclavulanate offers no advantages over amoxicillin or penicillin, as there have been no GAS isolates found to be resistant to beta-lactams Use of antibiotics other than amoxicillin in the non-allergic patient represents poor antimicrobial stewardship Up to 20% of U.S GAS isolates are resistant to macrolides and 20% to 25% to clindamycin Standard precautions should be used LOWER RESPIRATORY TRACT INFECTIOUS EMERGENCIES Lower respiratory tract infections are one of the most common causes of death in children younger than years of age in developing nations The morbidity of these infections in industrialized nations remains high The following section will review the diagnosis and management of pneumonia and other common lower respiratory tract infections Tuberculosis is covered separately later in this chapter in the section on infection in returned travelers, reflecting the epidemiology of this disease in industrialized nations Pneumonia CLINICAL PEARLS AND PITFALLS The most common causes of community-acquired pneumonia are viral infections Beyond the neonatal period, the most common bacterial cause is pneumococcus Less common, but more severe bacterial causes of pneumonia include S aureus and GAS While chest radiography can be useful to evaluate for complications of pneumonia, such as empyema or lung abscess, radiographic appearance alone is not useful for differentiating viral from bacterial etiologies Current Evidence The most common causes of pneumonia in different age groups are listed in Table 94.13 The most common causes are viral Among the bacteria, S pneumoniae predominates at every age beyond the newborn period S aureus causes a severe, rapidly progressive but uncommon pneumonia in young children; 60% of these infections occur in the first year of life GAS is also uncommon but may also be severe Anaerobic bacteria play a role primarily following aspiration TABLE 94.13 MOST COMMON CAUSES OF PNEUMONIA BY AGE Age Viral Pyogenic bacteria Other