Sinusitis 2000

8/10/2019 Sinusitis 2000

1/7

SinusitisDavid Nash, MD,* andEllen Wald, MD Objectives After completing this article, readers should be able to:

1. Describe the clinical presentation of acute and chronic sinusitis.2. Delineate the limited role for imaging studies in patients who have sinusitis.3. Recognize if abnormal images of the paranasal sinuses imply bacterial infection.4. Describe the microbiology of acute bacterial sinusitis.5. Delineate appropriate antimicrobial therapy based on knowledge of the microbiology of

acute bacterial sinusitis.

DenitionThe term sinusitis describes an inammation of the paranasal sinuses that can have a viral, allergic, or bacterial origin. The duration of respiratory symptoms can be used tocategorize patients who have sinusitis. Acute bacterial sinusitis (ABS) is dened by nasaland sinus symptoms that have been present at least 10 (in most cases) days and fewer than30 days. Subacute sinusitis is dened by nasal and sinus symptoms lasting longer than4 weeks and fewer than 12 weeks. There is very little information comparing acute andsubacute sinusitis, and this may ultimately prove to be an arbitrary distinction that does notaffect etiology, diagnosis, or treatment. Chronic sinusitis is dened by symptoms of at least12 weeks duration. Because the etiology of chronic sinusitis is often unknown, treatmentof this condition is controversial.

EpidemiologySymptoms affecting the upper respiratory tract (nasal congestion, rhinorrhea, and cough)are the most common complaint in the pediatric ofce. One of the greatest challengesfacing pediatricians is to distinguish between viral upper respiratory tract infections,allergic rhinitis, and sinusitis. A complicating factor is that both allergic rhinitis and viralupper respiratory tract infections predispose patients to acute or chronic sinusitis. Youngchildren experience six to eight viralupper respiratory tract infections per year, of which 5%to 10% areestimated to be complicated by ABS. Allergic rhinitis also is extremely common, with a prevalence approaching 20% by adolescence. It is essential that pediatriciansrecognize that both allergic rhinitis and viral upper respiratory tract infections are many times more common than ABS.

PathogenesisThe maxillary and ethmoid sinuses form during the third to fourth gestational month and,although very small, are present at birth. The maxillary sinuses are unique because theoutow tract sits high on the medial wall of the sinus cavity, thereby negating gravitationaleffects on drainage. The ethmoid sinus is comprised of multiple air cells, with each celldraining through a small, independent ostium into the middle meatus. The narrow caliberof these draining ostia predisposes to obstruction. The frontal sinus develops from ananterior ethmoid cell and moves to a position above the orbital ridge by the fth or sixthbirthday. The sphenoid sinuses are immediately anterior to the pituitary fossa and justbehind the posterior ethmoids. Isolated involvement of the sphenoid sinuses is rare; they usually are infected as part of a pansinusitis. The ostiomeatal complex (OMC) is the area

*Assistant Professor of Pediatrics, Division of Allergy, Immunology & Infectious Diseases, Childrens Hospital of Pittsburgh. Professor of Pediatrics and Otolaryngology, University of Pittsburgh School of Medicine; Chief, Division of Allergy, Immunology

& Infectious Diseases, Childrens Hospital of Pittsburgh, Pittsburgh, PA.

Article infectious diseases

Pediatrics in Review Vol.22 No.4 April 2001 111

8/10/2019 Sinusitis 2000

2/7

between the middle and inferior turbinates that repre-

sents the conuence of the drainage areas of the frontal,ethmoid, and maxillary sinuses (Figure). Within the

OMC are several sites in which two mucosal layers make

contact. Because the cilia move in opposite directions,secretions may be retained at these sites, creating thepotential for infection even without physical obstructionof the ostia.

PhysiologyThree key elements are important to the normal physiol-ogy of the paranasal sinuses: the patency of the ostia, thefunction of the ciliary apparatus, and the quality of secre-tions. Retention of secretions in the paranasal sinuses isusually due to one or more of the following: obstructionof the ostia, reduction in the number or function of thecilia, and overproduction or change in the viscosity of secretions.

The factors predisposing to ostial obstruction can bedivided into those that cause mucosal swelling and thosethat are due to mechanical obstruction (Table 1). Al-though many conditions may lead to ostial closure, viralrhinosinusitis and allergic inammation are the mostfrequent and most important. When the sinus ostium isobstructed completely, there is a transient increase inintrasinus pressure followed by the development of anegative intrasinal pressure. When the ostium opensagain, the negative pressure within the sinus cavity rela-tive to atmospheric pressure may allow the introductionof bacteria from the nasopharynx (which is heavily colo-nized with respiratory ora) into the usually sterile sinuscavity. Alternatively, sneezing, snifng, and nose blow-ing associated with altered intranasal pressure may facil-itate the entry of bacteria from the posterior nasal cham-ber into the sinuses.

The normal motility of the cilia and the adhesiveproperties of the mucous layer usually protect respiratory epithelium from bacterial invasion. The mucociliary ap-paratus may function abnormally because of either adirect cytotoxic effect on the cilia by respiratory viruses ora genetic defect in the microtubule structure of the cilia.The alteration of cilia number, morphology, and func-tion may facilitate secondary bacterial invasion of thenose and the sinuses. Cilia can beat only in a uidmedium. Alterations in the mucus, as in cystic brosis orasthma, may impair ciliary activity. The presence of pu-rulent material in the acutely infected sinus also may impair ciliary movement, further compounding the ef-fects of ostial closure.

Symptoms and Signs ABS has two common clinical presentations that distin-guish it from an uncomplicated episode of viral rhinosi-

nusitis. The most common presentation involves persis-

Figure. Coronal (A) and sagittal (B) sections of the nose andparanasal sinuses. The stippled areas represent the ostiomeatalcomplex. C. A view through the middle and superior turbi-

nates, displaying the ethmoid air cells.

infectious diseases sinusitis

112 Pediatrics in Review Vol.22 No.4 April 2001

8/10/2019 Sinusitis 2000

3/7

tent respiratory symptoms, including either nasaldischarge of any quality (thin or thick; clear, mucoid, orpurulent) or a cough that is present in the daytime,although it often worsens at night. Malodorous breathfrequently is reported by parents of preschoolers. Com-plaints of facial pain and headache are rare, although theparent may note occasional painless morning eye swell-ing. The child may not appear very ill, and if fever ispresent, it usually is low grade. The persistence ratherthan the severity of symptoms in this presentation is of note. In the context of ABS, persistent symptoms arethose that last from 10 to 30 days without improvement.The 10-day mark separates simple viral rhinosinusitisfrom ABS. Most uncomplicated episodes of viral rhi-nosinusitis last 5 to 7 days. Although patients may notbe asymptomatic by the tenth day, they are virtually always improved. Upper respiratory tract symptoms inchildren are common, but symptoms persisting forlonger than 10 days are seen in a minority ( 10%) of patients.

The second, less common presentation of ABS is acold that seems more severe than usual. The severity isdened by a combination of high fever (at least 39.0 o C[102.2 o F]) and purulent nasal discharge. The quality of nasal discharge changes frequently during the course of

an uncomplicated viral upper respiratory tract infection.

It begins as a watery discharge and becomes thicker,

colored, and opaque after a few days. Most often itremains purulent for several days, then clears again to amucoid or watery consistency before resolving. If fever ispresent during the course of an episode of viral rhinosi-nusitis, it is at the outset and in association with otherconstitutional symptoms such as headache and myalgias.Usually the fever disappears and the respiratory symp-toms begin. Accordingly, the combination of high feverand purulent nasal discharge for at least 3 to 4 consecu-tive days may signal a secondary bacterial infection of theparanasal sinuses. Affected patients may suffer fromheadaches behind or above the eye and occasionally

experience periorbital swelling.Patients who have subacute or chronic sinusitis

present with a history of protracted (more than 30 daysand not improving) respiratory symptoms. Nasal conges-tion (obstruction) and cough (day and night) are mostcommon. Sore throat results from mouth breathing dueto nasal obstruction. Nasal discharge (of any quality) andheadache are less common; fever is rare. It is important todistinguish between protracted symptoms and recurrentsymptoms because of implications for both etiology andtreatment.

In general, physical examination of children who haveeither acute or chronic upper respiratory tract symptomsis most helpful in identifying conditions that may predis-pose to sinusitis. Unfortunately, the examination cannotdistinguish between viral upper respiratory tract infec-tions and ABS. Patients who have nasal polyps, poorgrowth, clubbing of the ngers, barrel chest, and respi-ratory ndings may have cystic brosis. The immotilecilia syndrome almost always is associated with middleear disease, and 50% of patients have situs inversus. Thepresence of atopic dermatitis, intermittent wheezing,Morgan-Dennie lines (skin folds under the lower eyelid),

or a nasal crease suggests an allergic diathesis. Adenoidalhypertrophy either can predispose to ABS or, when theadenoids are infected, masquerade as sinusitis. The ade-noids cannot be assessed by routine examination, re-quiring instead either radiographic imaging or exibleendoscopy of the nasopharynx. Patients who have immu-nodeciency may lack tonsillar tissue and other lymphnodes and exhibit poor growth, clubbing of the ngers,and other signs of infection. However, normal ndingson the physical examination do not rule out the pos-sibility of immunodeciency, and if the clinical history is compelling, additional laboratory evaluation is ap-

propriate.

Table 1. Factors Predisposing toSinus Ostial ObstructionMucosal Swelling

Systemic disorder: Viral upper respiratory tract infection Allergic inammation Cystic brosis Immune disorders Immotile cilia Second-hand smoke

Local insult: Facial trauma Swimming, diving Rhinitis medicamentosa

Mechanical Obstruction Choanal atresia Deviated septum Nasal polyps Foreign body Tumor Ethmoid bullae Encephalocele



8/10/2019 Sinusitis 2000

4/7

Diagnostic Methods

The need, if any, for radiographic imaging (plain lm versus computed tomography [CT]) for children whohave symptoms of sinusitis is controversial. Recent na-tional guidelines on the treatment of sinusitis have em-phasized the role of the clinical diagnosis, moving away from the use of radiographic imaging in patients whohave uncomplicated ABS. Plain lms are appropriate inolder children who have recurrent acute sinusitis, vaguesymptoms, a poor response to antibiotic therapy, or ahistory of antibiotic hypersensitivity that makes therapy risky. Radiographic ndings in patients who have ABSinclude diffuse opacication, mucosal thickening of atleast 4 mm, or an air-uid level. When these radiographiccriteria were used in the clinical setting of either persis-tent or severe ABS, maxillary sinus aspirates con-tained a high density of bacteria in 75% of children.

CT should be reserved for patients who have eithercomplicated ABS or who are being considered as surgicalcandidates (for either recurrent or chronic sinusitis). When CT imaging is obtained in these circumstances, acomplete CT is indicated. Any patient who has proptosis,impaired vision, limited extraocular movements, severefacial pain, notable swelling of the forehead or face,deep-seated headaches, or toxic appearance should re-ceive a CT scan. The CT scan should not be used inpatients who have simple upper respiratory tract symp-toms because it does not distinguish between mucosalabnormalities due to viral infection and those due to ABS. CT scans of the paranasal sinuses in adults who hadacute colds showed substantial mucosal abnormalitiesthat resolved spontaneously, underscoring the fact thatmucosal abnormalities within the paranasal sinuses arecommon in patients who have upper respiratory tractsymptoms. In the setting of chronic sinusitis, the CT scanshould be used as a guide for surgical intervention forpatients who do not improve after completing maximalmedical therapy. CT scans appear normal in up to onethird of patients who have symptoms of chronic sinusitis.

Sinus Aspiration Although maxillary sinus aspiration is not a routine pro-cedure, it can be performed safely by a skilled otolaryn-gologist in the ambulatory setting using a transnasalapproach. Current indications for maxillary sinus aspira-tion include: 1) failure to respond to multiple courses of antibiotics, 2) severe facial pain, 3) orbital or intracranialcomplications, and 4) evaluation of an immunocompro-mised host. Material aspirated from the maxillary sinusshould be sent for quantitative aerobic and anaerobic

cultures (if possible), fungal cultures, and Gram stain.

The recovery of bacteria in a density of at least 10 4 cfu/mL

is considered to represent true infection. The nding of at least one organism per high-power eld on Gram stainof sinus secretions correlates with the recovery of bacteriain a density of 10 5 cfu/mL.

Microbiology of SinusitisData on the microbiology of patients who have acute(10 to 30 days) and subacute (30 to 120 days) illnesseshave highlighted the important bacterial pathogens asStreptococcus pneumoniae , Haemophilus inuenzae, andMoraxella catarrhalis. S pneumoniae is most common inall age groups, accounting for 30% to 40% of isolates.H inuenzae and M catarrhalis are similar in preva-lence, each accounting for approximately 20% of cases.Both H inuenzae and M catarrhalis may be beta-lactamase-producing and, therefore, resistant to amoxi-cillin. Neither staphylococci nor respiratory anaerobesare common in ABS. Respiratory viral isolates includeadenovirus, parainuenza, inuenza, and rhinovirus inapproximately 10% of patients. For children who havechronic sinusitis, the role of bacterial agents is less clear.The results of cultures from children who have chronicsinusitis have been extremely variable; a high percentageof patients have had either sterile cultures or knowncontaminants, and the presence of anaerobes has rangedfrom almost 0 to more than 90%. The persistence of symptoms despite multiple courses of antimicrobials iscounter to the hypothesis that bacterial pathogens play an important role in the etiology of chronic sinusitis.

Medical Treatment Antimicrobial therapy is the backbone of the medicalmanagement of ABS. Recent guidelines published jointly by the Centers for Disease Control and Prevention andthe American Academy of Pediatrics promoting theJudicious Use of Antimicrobial Agents suggest amoxi-cillin as a reasonable rst choice for most cases of ABS inchildren. This is especially true if the episode of ABS isuncomplicated and mild to moderate in severity and if the patient has not recently ( 1 mo) been treated withantimicrobial agents. The problem that has emergedduring the past 5 years in the management of ABS isinfection caused by S pneumoniae strains that are resis-tant to penicillin. The frequency of penicillin-resistantpneumococci varies geographically, and many isolates of pneumococci are resistant to other commonly used anti-microbials, such as cephalosporins, sulfamethoxazole-trimethoprim, and macrolides. Clinical situations in which alternative regimens are appropriate include:

1) failure to improve with conventional doses of amoxi-



8/10/2019 Sinusitis 2000

5/7

cillin, 2) recent treatment with amoxicillin ( 1 mo),

3) attendance at child care, 4) occurrence of frontal orsphenoidal sinusitis, and 5) presentation with protracted( 30 d) symptoms. Therapeutic options include high-dose amoxicillin (80 to 90 mg/kg per day), amoxicillin(45 mg/kg per day) plus amoxicillin with clavulanate(45 mg/kg per day), cefuroxime axetil, and cefpo-doxime. Antibiotic selection should be guided by suscep-tibility results when available.

Patients who have orbital or central nervous systemcomplications of sinusitis should be hospitalized andreceive a parenteral antibiotic, subspecialty consultation,and surgical drainage when appropriate. If penicillin-resistant pneumococci are suspected, cefotaxime(300 mg/kg per day in four doses) with or without vancomycin (60 mg/kg per day in four doses) should beadministered intravenously. The sinus should be aspi-rated to identify the infecting organism and aid in theselection of appropriate antimicrobial therapy.

Clinical improvement is prompt in nearly all childrentreated with an appropriate antimicrobial agent for un-complicated ABS. Patients who are febrile at the initialencounter will become afebrile, and there is a remarkablereduction of nasal discharge and cough within 48 to72 hours. If the patient does not improve or worsens in48 hours, clinical re-evaluation is appropriate. If thediagnosis is unchanged, sinus aspiration may be consid-ered to obtain precise bacteriologic information. Alter-natively, an antimicrobial agent effective against beta-lactamase-producing bacterial species and penicillin-resistant pneumococci should be prescribed.

The appropriate duration of antimicrobial therapy forpatients who have ABS has not been investigated system-atically. Most can be treated with 10 to 14 days of therapy. Longer treatment courses have been used inthose who have chronic sinusitis to avoid surgery. How-ever, the use of antibiotic therapy for more than a few weeks is not supported by clinical studies, exposes pa-tients to developing allergic hypersensitivity, and may increase the development of resistant organisms. Al-though antimicrobialprophylaxis has not been studied inpatients who have recurrent ABS, it has proved useful toreduce symptomatic episodes of acute otitis media inpatients who experience recurrent ear disease. A trial of antimicrobialprophylaxis may be appropriate for patientsin whom there is no treatable underlying disorder and who have a history of responding to antibiotic therapy.Patients selected for a trial of antibiotic prophylaxisshould have had at least three episodes of ABS in 6months or four episodes in 12 months.

Adjuvant therapies such as antihistamines, deconges-

tants, and anti-inammatory agents have received little

evaluation. Because antihistamines and decongestantshave not been studied in patients who have sinusitis andhave as much potential for harm as for benet, they should not be used for treatment of ABS. The potentialrole of topical intranasal steroids as an adjunct to antibi-otics has been evaluated recently in children and adults.The availability of agents that have a rapid onset of activity prompts their consideration for the managementof acute symptoms, but the very modest benecial effectof treatment does not justify their use. Nasal irrigationusing either hypertonic or isotonic solutions has beenshown to have a positive effect in some patients. Salinenasal irrigation is inexpensive, readily available, and de- void of side effects other than mild discomfort fromhypertonic solutions. Further prospective studies arenecessary to evaluate the role of these agents fully insinusitis.

ComplicationsThe major complications of ABS are rare and involvecontiguous spread of infection to the orbit, bone, orcentral nervous system (Table 2). Subperiosteal abscessof the orbit and intracranial abscesses are the most com-mon. Orbital infection is signaled by eye swelling, prop-tosis, and impaired extraocular eye movements; intra-cranial infection is suggested by signs of increasedintracranial pressure, meningeal irritation, and focal neu-rologic decits.

Table 2. Major Complications of SinusitisOrbital

Inammatory edema (preseptal or periorbitalcellulitis)

Subperiosteal abscess Orbital abscess Orbital cellulitis Optic neuritis

Osteomyelitis Frontal (Pott puffy tumor) Maxillary

Intracranial Epidural abscess Subdural empyema or abscess Cavernous or sagittal sinus thrombosis Meningitis Brain abscess



8/10/2019 Sinusitis 2000

6/7

Surgical Therapy

Patients who have ABS seldom require surgical interven-tion unless they present with orbital or central nervoussystem complications. Rarely, sinus aspiration may berequired in those who do not respond to aggressiveantimicrobial management both to ventilate the sinusesand to obtain material for culture. When patients whohave chronic sinusitis fail to improve with maximal med-ical therapy, sinus surgery might be considered. Oneacademic otolaryngology center has reported that com-prehensive evaluations for conditions that predisposechildren to chronic sinusitis combined with appropriatetherapy directed toward these conditions dramatically reduced the number of surgical procedures. At present,the focus of surgical therapy is the ostiomeatal complex.Using an endoscope, most current surgical efforts at-tempt to enlarge the natural meatus of the maxillary outow tract (by excising the uncinate process and theethmoid bullae) and perform an anterior ethmoidec-tomy. The outcome of endoscopic sinus surgery is dif-

cult to assess; all studies, including one meta-analysis,

have been limited by retrospective designs and an ab-sence of control groups. The precise population of chil-dren most likely to benet from this surgery has not beendelineated.

Suggested ReadingGwaltney JM, Phillips CD, Miller RD, Riker DK. Computed to-

mographic study of thecommon cold. N Engl J Med. 1994;330:2530

McAlister WH, Kronemer K. Imaging of sinusitis in children.Pediatr Infect Dis J. 1999;18:10191020

Parsons DS. Chronic sinusitis: a medical or surgical disease? Otolar- yngol Clin North Am . 1996;29:19

Wald ER, Milmoe GJ, Bowne A, Ledesma-Medina J, Salamon N,Bluestone CD. Acute maxillary sinusitis in children. N Engl J Med. 1981;304:749754

Wald ER, Reilly JS, Casselbrant M, et al. Treatment of acutemaxillary sinusitis in childhood: a comparative study of amoxi-cillin and cefaclor. J Pediatr. 1984;104:297302



8/10/2019 Sinusitis 2000

7/7

PIR QuizQuiz also available online at www.pedsinreview.org.

1. In considering empiric antibiotic therapy for a 17-year-old boy in whom you suspect acute sinusitis, youshould prescribe:

A. Amoxicillin 40 to 50 mg/kg per day.B. Cefotaxime 300 mg/kg per day.C. Cefuroxime axetil.D. Erythromycin succinate.E. Sulfamethoxazole-trimethoprim.

2. If the patients symptoms persist after 3 days of therapy, you should prescribe a course of:


3. One week later, the patient returns with erythema, swelling, and proptosis of the right eye. You hospitalizehim and prescribe intravenous:


4. Acute bacterial sinusitis is best distinguished from a viral upper respiratory tract infection by:

A. Cough.B. Duration of symptoms for greater than 10 days.C. Facial pain and headache.D. Presence of fever for 1 to 2 days.E. Purulent nasal drainage.

5. A diagnosis of acute bacterial sinusitis should be based on:

A. A precise clinical history regarding quality and duration of symptoms.B. Bacterial culture from the nasopharynx.C. Computed tomography of the paranasal sinuses.D. Physical examination of the nose and pharynx.E. Plain lm radiographs of the paranasal sinuses.



Sinusitis 2000

Documents

Transcript of Sinusitis 2000