A majority of sinus infections are viral in nature, and a thorough understanding of risk factors and symptoms will help clinicians know when antibiotics are needed.
Dr. Kyle is an assistant professor ofpharmacy practice at the McWhorterSchool of Pharmacy at SamfordUniversity, Birmingham, Alabama.Ms. Cortes is a 2009 PharmD Candidateat Palm Beach Atlantic University,Gregory School of Pharmacy, West PalmBeach, Florida.
Approximately 20 million casesof acute bacterial rhinosinusitis(ABRS) occur every yearin the United States.1 According toNational Ambulatory Medical CareSurvey data, ABRS is the fifth mostcommon reason physicians prescribeantibiotics.1 ABRS results in >1.5 millionambulatory care visits and anexpenditure of $5.3 billion yearly inthe cost of office visits, procedures,and antibiotics.2
ABRS usually follows a viral upperrespiratory tract infection, which canbe caused by human rhinovirus, respiratorysyncytial virus, adenovirus,parainfluenza, and enterovirus.1 ABRSalso can develop as a result of nose andparanasal sinus inflammation, whichcan be caused by dental infection, allergies,or trauma.
The most prevalent risk factor forABRS is having a recent viral upperrespiratory tract infection. Other riskfactors include allergic or nonallergicrhinitis, anatomical abnormalities (eg,a deviated septum or hypertrophic middleturbinates), diving and swimming,exposure to cigarette smoke, cysticfibrosis, and asthma.3
The most common signs and symptomsof ABRS tend to overlap withthose of viral upper respiratory tractinfections. These begin after an initialblockage of the maxillary sinus ostium,located beneath the middle turbinate.This blockage, along with mucus retentionand bacteria accumulation, bringabout such symptoms as nasal drainageand congestion; facial pain or pressure,especially when concentrated in 1 areaof the sinuses; postnasal drip; hyposmiaand, in some cases, anosmia; fever;cough; fatigue; and possible dental andear pain.1
According to a position paper ofthe Centers for Disease Control andPrevention, the American Academyof Family Physicians,the AmericanCollege of Physicians-American Societyof Internal Medicine, and the InfectiousDiseases Society of America, 4 signsand symptoms are the most beneficialin predicting ABRS4: purulent nasal discharge;maxillary tooth or facial pain,especially when it is unilateral; unilateralmaxillary sinus tenderness; andworsening symptoms after an initialimprovement.4
Due to overlapping symptoms, it oftencan be hard to properly diagnoseABRS. Physical examination providesvery little information. Computed axialtomography scans and magnetic resonanceimaging can be helpful at timesin the diagnosis, but are not necessaryfor ABRS.1 The ideal way to confirma diagnosis of ABRS is to aspirate thefluid from the affected sinuses andperform a culture.2,4 In the diagnosisof ABRS, the culture of the purulentsinus mucus should reveal at least 105 organisms per mL.4 This method isinvasive, time-consuming, and painfuland therefore not routinely performed.5In general, a diagnosis of ABRS is madein children and adults when signs andsymptoms have not improved after 10days or when the symptoms worsenover 5 to 7 days.1
The question of whether or not totreat ABRS is not easy to answer for anumber of reasons. Roughly 97.8% to99.5% of rhinosinusitis cases are due toa viral infection and therefore do notrequire treatment with an antibiotic.More often than not, however, antibioticsare still prescribed despite increasingantibiotic resistance.2,4
A recent meta-analysis in the Lancetanalyzed patient data from 9 randomizedtrials. The patient population included2500 intention-to-treat patients diagnosedwith ABRS who were randomizedto receive an antibiotic or placebo.6The outcome of interest was the proportionof patients cured.6 The resultsrevealed the calculated number neededto treat (NNT) was 15.6 In patients witha purulent discharge, the NNT droppedto 8, revealing that 8 patients need tobe treated before 1 additional patientis cured with antibiotics.6 The authorsconcluded that their results further validatedthat patients presenting with rhinosinusitisshould not receive an antibiotic,unless a diagnosis is confirmedby imaging or culture.6 Additionally,they emphasized their results are notevidence against prescribers wantingto wait and watch the symptoms beforetreating with an antibiotic.6
Should treatment be warranted, antibioticregimens are targeted to adult andpediatric patient populations and aredependent on severity of symptoms,b-lactam allergy status, and recent antibioticuse (Tables 1 and 2). In patientswho are at high risk for drug-resistantStreptococcus pneumoniae (DRSP),high-dose amoxicillin/clavulanate shouldbe used. Patients who are consideredhigh risk for DRSP include those whorecently have used antimicrobials(past 4-6 weeks), as well as those whoare immunodeficient, have recurrentsinusitis, or are a day care worker orattendee.
Those patients who do not respondto their prescribed antibiotic within 72hours and their symptoms are persistentor worsening should be reevaluated andan alternate agent be selected.1,7 Overall,the duration of treatment has not beenwell established. Most evidence-basedmedicine concludes that treatment durationshould last anywhere from 10 to 14days.7 Ancillary therapies that are sometimessuggested to patients who haveABRS may include oral decongestants,topical decongestants, antihistamines,and normal saline nasal spray. Theseancillary therapies for ABRS lack soundevidence, however.7 Whereas some trialshave shown an improvement in symptoms,no clinical trials have shown thatancillary therapy decreases the durationof the infection.7
Pharmacists have a duty to accuratelycounsel patients on ABRS and be awarethat the majority of sinus infectionsare viral in nature, and therefore donot require antibiotic therapy. Patientsshould be counseled on the signs andsymptoms, even if the watch-and-waitapproach is used. Pharmacists are animportant source of information forpatients on the use of antibiotics inABRS, while working closely with physicians.