ACUTE BACTERIAL SINUSITIS
Acute bacterial sinusitis is a bacterial infection of one or more of the paranasal sinuses lasting <30 days.1 The most common predisposing factor is a viral upper respiratory infection (URI). The incidence of viral URIs in children age 6 to 35 months is approximately six episodes per patient-year, with approximately 8% of those becoming complicated by acute bacterial sinusitis. Bacterial sinusitis in children is most common in the 12 to 23 months age group, probably because these children are most likely to be in daycare, predisposing them to URIs.2,3 The cost of acute pediatric bacterial sinusitis in the United States is approximately $20,000 per hospitalized patient, and a large geographic variation in healthcare utilization exists.4 Total healthcare costs in the United States incurred from treating sinusitis in children <12 years of age had been estimated at close to $2 billion a year.5
The sinuses are air cavities lined with ciliated columnar epithelium that helps mucus clearance by pushing mucus and debris out of the sinus ostia into the nasal cavity. Blockage of the ostia by mucus and inflammation predisposes to bacterial sinusitis. The ethmoid and maxillary sinuses are present at birth and are most commonly involved in sinusitis in children. The sphenoid sinuses form at 3 to 5 years of age. The frontal sinuses do not appear until 7 to 8 years of age and remain incompletely pneumatized until late adolescence. The most common predisposing factors for acute bacterial sinusitis are diffuse mucositis secondary to viral rhinosinusitis in about 80% and allergic inflammation in about 20%.6 Less common predisposing factors include nonallergic rhinitis, cystic fibrosis, dysfunctional or insufficient immunoglobulins, ciliary dyskinesia, and anatomic abnormalities.7
The most common pathogen of acute bacterial sinusitis is Streptococcus pneumoniae, recovered in 30% of children with acute sinusitis. Nontypeable Haemophilus influenzae and Moraxella catarrhalis are each recovered in 20%.7,8
Children with acute bacterial sinusitis typically present with high fever and purulent nasal discharge. Headache, particularly behind the eye, is variable. Complaints of facial pain in children are rare.2 Parents may report halitosis. The physical examination findings of acute bacterial sinusitis are often similar to those of uncomplicated viral sinusitis, with swollen and erythematous turbinates and mucopurulent discharge. However, reproducible unilateral tenderness to percussion or direct pressure of the frontal or maxillary sinus may indicate acute bacterial infection, and periorbital edema might indicate ethmoid sinusitis.2 Transillumination of the maxillary sinuses is unreliable in children <10 years of age.9
Although the gold standard for diagnosis of acute bacterial sinusitis is the recovery of ≥104 colony-forming units/mL of bacteria from the paranasal sinuses, sinus aspiration is painful and impractical in the ED.7 Therefore, diagnosis is often based on clinical criteria that help to distinguish acute bacterial sinusitis from an uncomplicated viral URI in an ill-appearing child (Table 123-1).1,10...