Sinusitis refers to inflammation of the paranasal sinuses. Allergic versus bacterial etiologies may be difficult to distinguish.18 Persistent URI symptoms suggest sinusitis.19 Children average two to seven viral URIs per year, of which approximately 13% are complicated by bacterial sinusitis.20 In addition to viral infection of the nasal passages and sinuses (viral rhinosinusitis), allergic rhinitis and atopy are the two most common predisposing factors for bacterial sinusitis.21 Other risk factors include day-care attendance, mucosal irritants such as tobacco smoke, foreign bodies, craniofacial abnormalities, septal deviation, adenoidal hypertrophy, and polyps secondary to allergies or cystic fibrosis (Fig. 95-4). Conditions that cause ciliary dysfunction and atmospheric pressure changes can also cause sinusitis.
Anatomy and Pathophysiology
While maxillary and ethmoid sinuses are present at birth, sphenoid sinuses become pneumatized after 5 years of age. Frontal sinuses appear by 6 to 8 years and complete development at adolescence. Sphenoidal and posterior ethmoidals drain into the ostium of the superior meatus on the lateral wall while the maxillary, frontal, and anterior ethmoidals drain into the middle meatus. Normal function of the paranasal sinuses depends on patency of the sinus ostia, the nature of sinus secretions, and function of the ciliary apparatus; abnormalities promote conditions for bacterial growth.22
Acute bacterial sinusitis presents in one of three manners22: (1) rhinorrhea (any quality) and cough (any quality, but usually more at night) >10 days and <30 days; (2) severe symptoms at onset marked by high fever lasting 3 to 4 days (longer than a typical viral infection) and mucopurulent rhinorrhea; (3) a biphasic pattern whereby symptoms worsen after a period of improvement. Headache, facial pain, and halitosis is variable and less common in children while fatigue, malaise, chronic cough, and decreased appetite are sometimes noted by parents.
On physical examination, there is anterior or postnasal drainage and swelling of the nasal mucosa. Signs of allergic rhinitis (e.g., allergic shiners, allergic salute, and cobblestoning of the posterior pharynx) may be present. Periorbital swelling suggests ethmoidal sinusitis. There may be frontal or facial tenderness to palpation, but transillumination is of limited value in children.
Acute uncomplicated bacterial sinusitis in children younger than 6 years can be diagnosed clinically.18,19,21 Although controversial, plain radiographs of the sinuses (anteroposterior, lateral, and occipitomental views) may be obtained in children older than 6 years to confirm the diagnosis or in those who do not improve after a course of antibiotics. Contrast enhanced CT may be indicated in the setting of treatment failures and complications (orbital or intracranial).23 Radiographic findings are often found even in patients with rhinosinusitis alone and cannot distinguish inflammation caused by viruses from that caused by bacteria leading to the variable reliability of radiographic evaluation, especially in the younger age group.22 However, normal studies are helpful in ruling out sinusitis.23 Findings in plain films or CT consistent with sinusitis include complete opacification of the sinus, mucoperiosteal thickening of more than 4 mm, and presence of air–fluid levels (Fig. 95-5).
CT scan showing pansinusitis.
Recurrent rhinitis, enlarged adenoids, and allergic rhinitis have similar symptoms to bacterial sinusitis. Foreign bodies, neoplasms, or polyps more commonly present with unilateral drainage and obstruction but may predispose to the development of sinusitis. Other causes of persistent cough such as gastroesophageal reflux, pertussis, and reactive airway disease should be considered. Over suctioning or too vigorous of nasal washes and the abuse/overuse of nasal decongestants (rhinitis medicamentosus) are iatrogenic causes of chronic nasal symptoms.
Direct extension from the sinuses can result in facial cellulitis, facial abscess, periorbital and orbital cellulitis, cavernous sinus thrombosis, epidural abscess, subdural empyema, meningitis, and brain abscess.18,22 Potts' puffy tumor, a subperiosteal abscess or osteomyelitis of the skull, is a rare complication of frontal sinusitis that presents with fever, headache, and forehead tenderness or swelling.24 Rarely, sinusitis may seed the systemic circulation resulting in bacteremia or septicemia.
There is limited and conflicting evidence to determine whether the use of antihistamines, decongestant, or nasal irrigation is efficacious in children with acute sinusitis.25 Nasal irrigation along with adjunct therapy may alleviate some symptoms (but not radiographic findings) in acute sinusitis in atopic children. A suspected viral etiology suggests supportive measures (bulb suctioning, limited use of vasoconstrictors). Saline nose drops may be useful in liquefying nasal secretions. Although some children with sinusitis will improve gradually, antibiotic therapy is indicated to hasten resolution of symptoms and to prevent complications.18,26 The pathogenesis and microbiology of acute bacterial sinusitis are similar to acute otitis media because the middle ear is contiguous with the paranasal sinuses.
Although S. pneumoniae, nontypeable H. influenzae, and M. catarrhalis have been the most common causes, a decrease in the incidence of S. Pneumonia and a corresponding increase in nontypeable H. influenzae, may be attributable to the introduction of the pneumococcal conjugate vaccines.27 Prior to the era of beta-lactamase resistance, amoxicillin was once thought to be the mainstay of treatment. However, the Infectious Diseases Society of America has recently published recommendations for the management of acute bacterial sinusitis which includes the prompt treatment with high-dose amoxicillin-clavulanate (90 mg per kilogram per day, administered in two doses) as first-line therapy for children.26 This is particularly where penicillin resistance S. pneumoniae strains are endemic and resistance is 10% higher, those in day care, those younger than 2 years of age, and those who have been hospitalized or treated with antibiotics in the last 30 days.26 Alternatively, although not FDA approved, Levofloxacin is recommended for children with a history of type 1 hypersensitivity reaction to penicillin.22,26 Cefdinir (14 mg/kg/d in one or two doses), cefuroxime (30 mg/kg/d), or cefpodoxime (10 mg/kg/d) may be used in conjunction with clindamycin (30–40 mg/kg/d in three divided doses).18,19 Macrolides and trimethoprim–sulfamethoxazole are not recommended because of high rates of resistance in the United States.26 For patients who are vomiting, a single dose of ceftriaxone (50 mg/kg/d intramuscularly or intravenously) can be used with initiation of oral antibiotics 24 hours later once vomiting has subsided. Oral antibiotics can be given for a minimum of 10 to 14 days and extended depending on the clinical response. However, most patients will have improvement in their symptoms within 48 to 72 hours. Patients with severe symptoms, clinical deterioration while on oral antibiotics, immunodeficiency, or orbital or intracranial involvement, should be hospitalized for IV antibiotics, sinus imaging studies and consultation with an otolaryngologist. Parenteral antibiotic coverage against resistant pneumococci, H. influenzae, and M. catarrhalis includes cefotaxime (100–200 mg/kg/d divided every 6 hours) or ceftriaxone (100 mg/kg/d divided every 12 hours) with consideration for adding clindamycin.19