Acute bacterial sinusitis (ABS) complicates approximately 5% to 10% of pediatric cases of viral upper respiratory infections (URIs). Children younger than age 5 years can experience 2 to 7 episodes of URI per year and this incidence is even higher (up to 14 per year) among those attending day care centers.1,2 Wald et al.3 reported the rate of sinusitis complicating a preceding URI to be 6.5% to 15%. In a study of children between ages 6 and 36 months with URI, ABS occurred in 8% of them, and the average age at diagnosis was 18.8 ± 7.2 months.4 Sinusitis complicated 8.8% of viral URI episodes in another study conducted on children between ages 4 and 7 years.5 Children attending day care are 2 times more likely to develop sinusitis after an episode of viral URI as compared to those not attending day care.3 ABS and its complications have been estimated to account for 23 million health care visits annually in the United States at a cost of $1.8 billion for children age 12 years and younger.6
Viral URI is the most common predisposing factor for ABS. With the onset of viral infection, the ciliated epithelium of the nasal cavity becomes less functional and the nasal secretions are not cleared well from the nasal cavity. The ostia of the sinuses are obstructed because of inflammation of the mucosa as a result of URI, and this leads to impaired mucous clearance from the sinuses. Negative pressure is created within the obstructed sinuses due to absorption of air by inflamed mucosa, which is further augmented by blowing and sniffing during URI. Because of this negative pressure in the sinuses, stagnant mucous laden with respiratory bacterial pathogens in the nasal cavity is pulled into the sinuses, thus creating an infection in the sinus cavity.1,2
Other factors that cause ostial obstructions and predispose to acute bacterial sinusitis are seasonal allergies, cystic fibrosis, nasal polyps, deviated nasal septum, ciliary motility disorders, foreign bodies in nasal cavity, drug-induced rhinitis, and trauma to the nose.2
Clinicians often face the challenge of differentiating between a viral URI and ABS. As it is mostly a complication of acute viral URI, the symptoms of ABS often overlap with those of acute viral URI. Uncomplicated viral URIs typically last for 5 to 10 days3,7–9 (Figure 1). Respiratory symptoms of viral URI include runny nose, nasal congestion, and cough, which usually peak between 3 and 6 days. Fever, if present, typically occurs early in the course of URI often with concomitant systemic symptoms such as headache and myalgia. These symptoms generally last up to 48 hours. Nasal drainage of uncomplicated URI changes its appearance from clear and thin in the beginning to thick mucoid or mucopurulent in the later part of illness before resolving by 7 to 10 days. ABS complicates viral URI in one of three ways. The most common presentation of ABS is the persistence of viral URI symptoms beyond 10 days, marked by nasal drainage of any kind (clear, mucoid, or mucopurulent) or day time cough or both. ABS can also present with high fever (>102.2°F) and concomitant purulent nasal drainage during the initial 3 to 4 days of illness. A child who appears ill with prolonged duration of fever in this presentation differentiates it from uncomplicated viral URI. Another clinical presentation of ABS is characterized by worsening of URI symptoms after initial improvement, also known as “double sickening.” This presentation typically occurs by day 6 or day 7 of illness and is marked by worsening of nasal discharge or congestion, relapse or onset of new fever, and worsening of daytime cough. Other symptoms noted are facial pain, poor appetite, headache, and body ache. Halitosis is often present, although is not specific to ABS.
Timeline of course of fever and respiratory tract symptoms in uncomplicated viral upper respiratory infection. Reprinted with the permission of Elsevier from Wald.2
On examination, nasal mucosa may be erythematous, pale, or boggy. Postnasal drip of mucopurulent drainage can be seen on posterior pharyngeal wall. Periorbital edema and discoloration of eye lids is often seen. Itching and redness of eyes may be present if atopy and seasonal allergies are the predisposing factors. Cervical lymphadenopathy is generally not seen.2,9 ABS can sometimes present with symptoms of its complications, which is discussed later in this article.
Diagnosis and Evaluation
The diagnosis of ABS in children is made based on clinical symptoms as outlined in the Clinical Practice Guidelines by the American Academy of Pediatrics (AAP).9 Presumptive diagnosis of ABS can be made when a child presents with any one of the following clinical scenarios: (1) persistent illness with nasal discharge of any quality or day time cough or both lasting more than 10 days without improvement; (2) worsening or new onset of nasal discharge, day time cough, or fever after initial improvement; and (3) severe onset of illness marked by high fever (>102.2°F) and purulent nasal drainage.
Imaging studies such as X-ray, computed tomography (CT) scan, magnetic resonance imaging (MRI), or ultrasound of paranasal sinuses are not recommended to diagnose uncomplicated ABS, unless complication of ABS is suspected.9 Young adults with common cold symptoms for 48 to 96 hours (80%) who underwent CT scan were found to have abnormal mucosal inflammation in the paranasal sinuses.10 Mucosal swelling was found in maxillary and ethmoid sinuses of approximately 60%, sphenoid sinuses of 35%, and frontal sinuses of 18% of the MRIs done on children with symptoms of uncomplicated acute respiratory infection.11 These findings are nonspecific and can also be seen in patients with viral rhinitis as the nasal mucosa is in continuity to mucosa of paranasal sinuses, thus imaging studies should not be performed in the evaluation of ABS.9 CT or MRI with contrast of paranasal sinuses is useful and recommended for evaluation of patients suspected to have complications of ABS. There are no comparative data available about the superiority of kind of imaging modality, but in general CT scan is preferred over MRI when orbital or intracranial complication of ABS is suspected as the findings are better visualized.9
Microbiology of Acute Bacterial Sinusitis
The most common pathogens found by direct aspiration of maxillary sinus in old studies were Streptococcus pneumoniae (30%), Haemophilus influenzae (20%), and Moraxella catarrhalis (20%). Other less frequently found pathogens were Group A streptococcus, Eikenella corrodens, alpha hemolytic streptococcus, and Peptostreptococcus.12,13 In a study, nasopharyngeal secretions were cultured from 82 children with ABS, of which 8 (10%) grew S. pneumoniae, 5 (6%) grew H. influenzae, 16 (20%) grew M. catarrhalis, and 46 (56%) cultures were polymicrobial with M. catarrhalis being the most common pathogen.4 Since the introduction of conjugated pneumococcal vaccine, isolation rates of S. pneumoniae have decreased with relative increase in rates of H. influenzae.14
Due to conflicting results of studies evaluating the outcomes of treatment of ABS with antibiotics, treatment of ABS has been an area of controversy.15 A randomized double-blinded placebo-controlled study comparing amoxicillin with amoxicillin-clavulanate showed cure rates of 67% with amoxicillin, 64% with amoxicillin-clavulanate, and 43% with placebo.16 Garbutt et al.17 found no difference in outcomes between the placebo group and two groups treated with amoxicillin and amoxicillin-clavulanate, respectively.17 In a more recent study, significantly higher cure rates and fewer failure rates were found among the amoxicillin treatment group versus the placebo group.18
Per AAP guidelines,9 treatment with antibiotics is recommended at the first encounter with patients presenting with clinical scenarios of “severe onset” and “worsening illness.” The rationale for treating these groups is that presentation of high fever even after 3 to 4 days of illness along with purulent nasal discharge (severe onset) or with new onset of fever after initial improvement (worsening illness) is not consistent with typical uncomplicated viral illness that resolves with steady improvement. Treatment of these groups has proposed benefits of increased clinical cures, shortening duration of illness, and decrease in incidence of suppurative complications.9
In the clinical scenario of persistent illness, clinicians are recommended to either treat the patient with antibiotics or to observe for a period of 3 days. The choice between these two options may be influenced by factors such as severity of symptoms, recent antibiotic exposure, effect of illness on the quality of the child's life, previous experience with the patient, input of the caregiver, cost, and compliance. Patients who received antibiotics within 4 weeks of presentation, or have concomitant infection such as pneumonia, cervical lymphadenitis, acute otitis media, or group A streptococcal pharyngitis should be treated with antibiotics. Children with underlying conditions such as asthma, cystic fibrosis, immunodeficiency, and anatomic abnormalities of respiratory tract should also be treated with antibiotics. If patients who are managed with initial observation without antibiotics fail to improve after 3 days, clinicians may start amoxicillin or continue to observe without treatment after discussion and shared decision-making with the caretaker. If these patients show worsening after 3 days of initial observation, amoxicillin with or without clavulanate, should be started for such patients.9
Considering the increasing rates of beta lactamase (BLM) production and the increasing emergence of H. influenzae as a cause of ABS in children, the Infectious Diseases Society of America recommends treating ABS with amoxicillin-clavulanate.19 AAP recommends amoxicillin or amoxicillin-clavulanate for the treatment of ABS depending on the clinical scenario as described below. Amoxicillin at the dose of 45 mg/kg/d in two divided doses (maximum 2 g per dose) remains the first-line treatment for uncomplicated ABS in children older than age 2 years with mild to moderate illness who have not been previously treated within 4 weeks, do not attend day care, and are from communities where resistance of S. pneumoniae to penicillin (PCN) is estimated to be less than 10%. In communities where resistance of S. pneumoniae to PCN is estimated to be more than 10%, treatment with a different dosage of amoxicillin (80 to 90 mg/kg/d in two divided doses, maximum 2 g per dose) is recommended. Children who have moderate to severe illness or attend day care or have been treated with antibiotics within previous 4 weeks or who are younger than age 2 years should be treated with amoxicillin-clavulanate (80–90 mg/kg/d of amoxicillin component and 6.4 mg/kg/d of clavulanate, in two divided doses). Children with poor oral tolerance for antibiotic or vomiting can be treated with intravenous (IV) ceftriaxone at 50 mg/kg/d until improvement is noted before switching to oral route to complete the course. Duration of treatment can be tailored per the patient's response to therapy with a minimum of 7 more days after resolution of symptoms.9
As clinical improvement is expected after 72 hours of antibiotic treatment based on previous trials, clinicians should physically reevaluate patients with progression of signs and symptoms or with onset of new symptoms or lack of improvement of initial symptoms after 72 hours of therapy. If a diagnosis of ABS is confirmed on reevaluation, clinicians should change the antibiotics to high-dose amoxicillin-clavulanate in patients who worsen after 72 hours of amoxicillin therapy. For patients who do not improve after 72 hours of initial amoxicillin therapy, clinicians may choose to continue amoxicillin with observation or may choose to change antibiotics to high-dose amoxicillin-clavulanate. Clinicians may choose to continue high-dose amoxicillin-clavulanate or change the treatment to combination of clindamycin and cefixime or linezolid and cefixime in patients not improving after initial 72 hours of high-dose amoxicillin-clavulanate therapy. Patients who show clinical worsening after 72 hours of treatment with high-dose amoxicillin-clavulanate can be switched to a combination of clindamycin and cefixime or linezolid and cefixime to cover for PCN-resistant S. pneumoniae.9
Children with both type 1 and non-type 1 allergic reaction to amoxicillin can be treated with cefdinir, cefuroxime axetil, or cefpodoxime. Children younger than age 2 years with severe type 1 reaction to PCN and moderate to severe sinusitis should be treated with combination of clindamycin (or linezolid) and cefixime to cover for resistant S. pneumoniae and resistant H. influenzae.
Once intracranial involvement is confirmed with imaging, IV vancomycin should be started empirically to cover methicillin-resistant staphylococcus aureus (MRSA). IV ceftriaxone or ampicillin-sulbactam and IV metronidazole should be added to vancomycin to empirically treat S. pneumoniae and respiratory gram negative and anaerobic organisms, respectively. In patients with intracranial involvement, timely neurosurgical consultation should be obtained.9
A recent Cochrane review of 662 studies evaluating efficacy of decongestants, antihistamines, and nasal irrigation could not find even one study suitable enough for inclusion in the review. Authors concluded that there is no evidence to suggest that these modalities are efficacious in children with ABS.20 Two studies evaluating topical steroids in children with acute sinusitis showed high rates of improvement in symptoms, although the studies were found to have methodological errors and confounding factors due to lack of strict inclusion criteria.21,22 Thus, no concrete conclusion has been made about the efficacy of topical steroids in ABS.9
ABS is complicated by orbital and intracranial involvement in about 5% of hospitalized patients.23 Orbital involvement is the most common form of complication from ABS. Ethmoid sinuses are separated from the orbit by a very thin bony membrane called Lamina papyracea. Children are more susceptible due to the thinner bony septum and porous bones.23,24 Orbital complications are divided into five categories depending on the extent and severity of involvement.25
Preseptal cellulitis is the first category. It is the most common form of mild orbital involvement marked by swelling (sometimes swollen shut) and erythema of the eye lids. This is thought to be caused by venous obstruction of the ethmoidal vessels by pressure of the inflammation in the ethmoid sinus. Orbital cellulitis is the second category of orbital involvement and is characterized by inflammation of the orbital contents. Signs and symptoms of orbital cellulitis include mild to moderate proptosis, limitation and pain with eye movements, chemosis, and visual complaints. Subperiosteal abscess and orbital abscess are the third and fourth categories, wherein pus collects underneath the periosteum of the orbit or within the orbit, respectively. Symptoms include severe proptosis, chemosis, visual impairment, restriction of eye movements, and even ophthalmoplegia. Visual loss can occur due to retinal artery occlusion caused by increased pressure within the orbit and needs emergent surgical decompression.23 Clinical signs of proptosis and ophthalmoplegia are helpful in the differentiation of orbital pathology (orbital cellulitis, subperiosteal abscess, and orbital abscess) from preseptal cellulitis with positive predictive value of 97% and negative predictive value of 93%.26
The fifth category of cavernous sinus thrombosis is a severe complication of ABS. Orbital veins that drain the infected orbital contents lack valves promoting the spread of infection posteriorly into the cavernous sinus.23 Clinical features include high fever, signs of systemic toxicity, headache, fever, vomiting, photophobia, proptosis, ophthalmoplegia, orbital pain, chemosis, and visual loss.27 Rarely symptoms arising from cranial nerves (3 to 6) palsy, such as mydriasis, decreased periorbital sensations, and diplopia, can occur.27
Intracranial complications after ABS are estimated to occur in 5% to 30% among patients who are hospitalized, although overall rates are likely to be much lower as ABS is mostly treated in a clinic setting.23,24 Frontal sinusitis is more likely to lead to intracranial spread as the posterior wall of frontal sinus is in close proximity to meninges and the brain, leading to meningitis, epidural empyema, subdural empyema, or brain abscess. These complications tend to occur in older children and adolescents due to late development of frontal sinus. Epidural empyema is the most common intracranial complication of ABS. Symptoms include headache, fever, nausea, vomiting mental status changes, seizures, or focal neurological deficits.24 Pott's puffy tumor is another known complication of frontal sinus infection and presents as swelling on the forehead due to underlying subperiosteal abscess and osteomyelitis of frontal bone.28
Recurrent Acute Bacterial Sinusitis
Recurrent acute bacterial sinusitis (RABS) is characterized by recurring episodes (at least 4 per year) of ABS, each lasting less than 30 days and separated by at least 10 days of an asymptomatic period. Patients with RABS should undergo evaluation for underlying predisposing factors such as cystic fibrosis, immunodeficiency disorders, dysmotile cilia syndrome, reflux diseases, nasal polyps, deviated nasal septum, and other anatomic abnormalities of nasal cavity. Children with documented RABS and no recognizable predisposing factor may benefit from prophylactic antibiotics during the peak period of viral infections, although such strategy poses the risk of selecting resistant pathogens.9
Chronic rhinosinusitis (CRS) is defined as a complex inflammatory condition of the nasal cavity and paranasal sinuses that lasts longer than 12 weeks despite medical therapy. The pathophysiology of CRS is complex and all the predisposing factors of RABS are known triggers for CRS as well. Poor mucociliary clearance leads to colonization of sinus cavities with multiple pathogens, some of which make biofilms that are difficult to eradicate. The emergence of BLM-producing pathogens found in cases of CRS provides a shield to other non–BLM-producing pathogens, thus causing persistence of infection. Microbiology of CRS is an area of controversy with no consensus in literature and is thought to be different from that found in ABS. Staphylococcus aureus and anaerobes play an important role in addition to the typical pathogens found in ABS. Peptostreptococcus, Porphyromonas, Prevotella and Fusobacterium are common anaerobes implicated in CRS many of which produce BLM along with beta-lactamase producing S. aureus. Gram-negative pathogens such as Pseudomonas aeruginosa, Escherichia coli, and Klebsiella have been recovered from patients with underlying conditions such as cystic fibrosis and other immunocompromising conditions including neutropenia, diabetes mellitus, HIV, and others. The treatment approach of CRS is a combination of managing the underlying predisposing factor, relieving the obstruction of the sinus cavity, and antibiotics. Topical steroids and antibiotics comprise the medical management of CRS.29 A panel of otolaryngologists recommend prolonged course (20 days) of susceptibility based antibiotic treatment for CRS.30 Medical management alone often is unsuccessful and a surgical procedure such as functional endoscopic sinus surgery is frequently used for cases that fail medical management.29
ABS is one of the common diagnosis encountered in pediatric patients, mostly as persistence of illness of viral URI. Evaluation with imaging modalities should not be done in patients with simple illness unless signs and symptoms suggestive of complications are present. Antibiotics should be prescribed for patients presenting with severe onset or worsening illness, whereas observation for 3 days in patients with persisting URI symptoms and reliable follow-up is suitable. If symptoms persist or worsen after 3 days, then therapy may be started. Therapy can also be changed in patients if there is persistence or worsening of symptoms after 3 days of initial treatment.
- Revai K, Dobbs LA, Nair S, Patel JA, Grady JJ, Chonmaitree T. Incidence of acute otitis media and sinusitis complicating upper respiratory tract infection: the effect of age. Pediatrics. 2007;119(6):e1408–1412. doi:. doi:10.1542/peds.2006-2881 [CrossRef]
- Wald ER. Sinusitis. In: Long SS, Pickering LK, Charles G, eds. Principles and Practice of Pediatric Infectious Diseases. Philadelphia, PA: Elsevier. 2012: 227–231.
- Wald ER, Guerra N, Byers C. Upper respiratory tract infections in young children: duration of and frequency of complications. Pediatrics. 1991;87(2):129–133.
- Marom T, Alvarez-Fernandez PE, Jennings K, Patel JA, McCormick DP, Chonmaitree T. Acute bacterial sinusitis complicating viral upper respiratory tract infection in young children. Pediatr Infect Dis J. 2014;33(8):803–808. doi:. doi:10.1097/INF.0000000000000278 [CrossRef]
- DeMuri GP, Gern JE, Moyer SC, Lindstrom MJ, Lynch SV, Wald ER. Clinical features, virus identification, and sinusitis as a complication of upper respiratory tract illness in children ages 4–7 years. J Pediatr. 2016;171:133–139.e1. doi:. doi:10.1016/j.jpeds.2015.12.034 [CrossRef]
- Ray NF, Baraniuk JN, Thamer M, et al. Healthcare expenditures for sinusitis in 1996: contributions of asthma, rhinitis, and other airway disorders. J Allergy Clin Immunol. 1999;103(3 Pt 1):408–414. doi:10.1016/S0091-6749(99)70464-1 [CrossRef]
- Pappas DE, Hendley JO, Hayden FG, Winther B. Symptom profile of common colds in school-aged children. Pediatr Infect Dis J. 2008;27(1):8–11. doi:. doi:10.1097/INF.0b013e31814847d9 [CrossRef]
- Wald ER, Guerra N, Byers C. Frequency and severity of infections in day care: three-year follow-up. J Pediatr. 1991;118(4 Pt 1):509–514. doi:10.1016/S0022-3476(05)83370-0 [CrossRef]
- Wald ER, Applegate KE, Bordley C, et al. Clinical practice guideline for the diagnosis and management of acute bacterial sinusitis in children aged 1 to 18 years. Pediatrics. 2013;132(1):e262–280. doi:. doi:10.1542/peds.2013-1071 [CrossRef]
- Gwaltney JM Jr, Phillips CD, Miller RD, Riker DK. Computed tomographic study of the common cold. N Engl J Med. 1994;330(1):25–30. doi:. doi:10.1056/NEJM199401063300105 [CrossRef]
- Kristo A, Uhari M, Luotonen J, et al. Paranasal sinus findings in children during respiratory infection evaluated with magnetic resonance imaging. Pediatrics. 2003;111(5 Pt 1):e586–589. doi:10.1542/peds.111.5.e586 [CrossRef]
- Wald ER, Milmoe GJ, Bowen A, Ledesma-Medina J, Salamon N, Bluestone CD. Acute maxillary sinusitis in children. N Engl J Med. 1981;304(13):749–754. doi:. doi:10.1056/NEJM198103263041302 [CrossRef]
- Wald ER, Reilly JS, Casselbrant M, et al. Treatment of acute maxillary sinusitis in childhood: a comparative study of amoxicillin and cefaclor. J Pediatr. 1984;104(2):297–302. doi:10.1016/S0022-3476(84)81018-5 [CrossRef]
- Casey JR, Adlowitz DG, Pichichero ME. New patterns in the otopathogens causing acute otitis media six to eight years after introduction of pneumococcal conjugate vaccine. Pediatr Infect Dis J. 2010;29(4):304–309. doi:10.1097/INF.0b013e3181c1bc48 [CrossRef].
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- Wald ER, Chiponis D, Ledesma-Medina J. Comparative effectiveness of amoxicillin and amoxicillin-clavulanate potassium in acute paranasal sinus infections in children: a double-blind, placebo-controlled trial. Pediatrics. 1986;77(6):795–800.
- Garbutt JM, Goldstein M, Gellman E, Shannon W, Littenberg B. A randomized, placebo-controlled trial of antimicrobial treatment for children with clinically diagnosed acute sinusitis. Pediatrics. 2001;107(4):619–625. doi:10.1542/peds.107.4.619 [CrossRef]
- Wald ER, Nash D, Eickhoff J. Effectiveness of amoxicillin/clavulanate potassium in the treatment of acute bacterial sinusitis in children. Pediatrics. 2009;124(1):9–15. doi:. doi:10.1542/peds.2008-2902 [CrossRef]
- Chow AW, Benninger MS, Brook I, et al. IDSA clinical practice guideline for acute bacterial rhinosinusitis in children and adults. Clin Infect Dis. 2012;54(8):e72–e112. doi:. doi:10.1093/cid/cis370 [CrossRef]
- Shaikh N, Wald ER. Decongestants, antihistamines and nasal irrigation for acute sinusitis in children. Cochrane Database Syst Rev. 2014(10):CD007909. doi:10.1002/14651858.CD007909.pub4 [CrossRef].
- Barlan IB, Erkan E, Bakir M, Berrak S, Baaran MM. Intranasal budesonide spray as an adjunct to oral antibiotic therapy for acute sinusitis in children. Ann Allergy Asthma Immunol. 1997;78(6):598–601. doi:. doi:10.1016/S1081-1206(10)63223-1 [CrossRef]
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- Arora HS, Abdel-Haq N. A 14-year-old male with swelling of the forehead. Pott's puffy tumor. Pediatr Ann. 2014;43(12):479–481. doi:. doi:10.3928/00904481-20141124-05 [CrossRef]
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