Continuing Education Activity

Sinusitis, also referred to as rhinosinusitis, is the symptomatic inflammation of the paranasal sinuses and nasal cavity mucosa. This inflammation may be caused by viruses, bacteria, fungi, or allergens. Recurrent acute sinusitis (RARS) is defined as four or more rhinosinusitis episodes per year without persistent symptoms between episodes. This activity highlights the role of the interprofessional team in the evaluation and management of patients with recurrent acute sinusitis.

Objectives:

• Identify the etiology of recurrent acute sinusitis (RARS).
• Review the evaluation of a patient with recurrent acute sinusitis (RARS).
• Outline the available options for managing recurrent acute sinusitis (RARS).
• Describe interprofessional team strategies for improving care coordination and outcomes in patients with recurrent acute sinusitis (RARS).

Introduction

Sinusitis, also referred to as rhinosinusitis, is the symptomatic inflammation of the paranasal sinuses and nasal cavity mucosa. This inflammation may be caused by viruses, bacteria, fungi, and allergens. Criteria for diagnosing rhinosinusitis were established in 1997 by the Rhinosinusitis Task Force.[1] Symptoms were divided into two categories: major criteria and minor criteria. The diagnosis of sinusitis requires the presence of either two major factors or one major plus two minor factors. The diagnostic criteria are as follows:

• Major 
• • Purulence on nasal examination
  • Nasal obstruction/blockage
  • Nasal discharge/purulence/discolored posterior drainage
  • Hyposmia/anosmia
  • Fever
  • Facial pain/pressure
  • Facial congestion/fullness
• Minor
• • Ear pain/pressure/fullness
  • Cough
  • Dental pain
  • Fatigue
  • Halitosis
  • Fever
  • Headache

Rhinosinusitis may also be classified according to the duration of symptoms. Acute rhinosinusitis lasts fewer than four weeks; subacute sinusitis lasts between 4 and 12 weeks; chronic sinusitis lasts more than 12 weeks. Recurrent acute rhinosinusitis (RARS) is defined as four or more episodes of acute rhinosinusitis per year, each lasting at least ten days, without persistent symptoms in between these distinct episodes.[2] This article will focus primarily on recurrent acute rhinosinusitis and include information on patient presentation, diagnosis, and intervention. 

Etiology

The most common etiologies for recurrent acute rhinosinusitis mirror the other subtypes of sinusitis. Viral upper respiratory tract infections are the most common cause of sinusitis and are typically self-limiting.[3] Viral inoculation causes inflammation and irritation of the nasal cavity mucosa and paranasal sinuses. This inflammation reduces the size of the sinus ostia (openings) and obstructs the clearance of nasal flora, mucus, and inhaled particles. Inflammation alters the frequency of ciliary movement and causes mucus stasis, which predisposes the sinuses to bacterial infection. The most common bacterial pathogens causing recurrent acute rhinosinusitis are Streptococcus pneumoniae, Haemophilus influenzae, other Streptococcus species, Moraxella catarrhalis, and Staphylococcus aureus.[4] Methicillin-resistant Staphylococcus aureus (MRSA) often colonizes the nares and leads to recurrent sinusitis, especially in patients who have already received multiple courses of antibiotics.

There tends to be some etiologic overlap between recurrent acute rhinosinusitis and chronic rhinosinusitis. Non-invasive fungal pathogens such as Aspergillus fumigatus may be isolated in these patients. Anatomic obstructive abnormalities, including turbinate hypertrophy, conchae bullosa, stenosed sinus ostia, Haller cells, nasal polyposis, nasal masses, and septal spurs/deviation, can predispose the nasal cavity and sinuses to infection.[5][6] These structural abnormalities are often amenable to correction with endoscopic surgical techniques. Genetic factors that affect nasociliary motion or mucus production have been postulated to play a role in the pathophysiology of this disease. Environmental factors such as tobacco smoke, chronically inhaled irritants, or nasal packing have also been implicated in the developmental or exacerbation of recurrent acute rhinosinusitis.[7]

Epidemiology

Sinusitis is one of the most common conditions for which patients seek medical attention, with one in 8 adults being diagnosed with at least one episode of sinusitis during their lifetime.[8] Sinusitis is the indication for twenty percent of all antibiotic prescriptions.[9] In 2015, thirty million cases of sinusitis were diagnosed in the United States.[4] The direct cost of treating sinusitis is more than $11 billion in the United States, with $3 billion spent on acute sinusitis and $8.3 billion spent on chronic sinusitis. In a review of a medical claims database of 13.1 million people from 2003 to 2008, the prevalence of recurrent acute rhinosinusitis was found to be 1 in 3,000. In this study, females accounted for the majority (72.1%) of the affected population and had a mean age of 43.5 years. The average numbers of annual health care visits and prescriptions filled were 5.6 and 9.4 per patient, respectively, with an annual direct cost burden of $1091 per patient.[10]

Pathophysiology

The pathogenesis of rhinosinusitis involves a combination of viscous sinus secretions and the dysfunction of the sinus ostia and ciliary apparatus. Viral upper respiratory infections or allergens may cause mucosal edema, narrowing the sinus ostia and causing a direct mechanical obstruction. The obstruction of the sinus ostia leads to a transient increase in pressure within the sinus cavity. As air is depleted in this small space, the pressure in the sinus becomes negative relative to atmospheric air pressure. This negative pressure allows nasal bacteria into the sinuses during normal physiologic maneuvers (e.g., sniffing or nose-blowing). Continued mucus secretion in the setting of an obstructed sinus ostium leads to fluid accumulation in the sinus. Inflammation of the nasal ostia and mucous membranes causes structural and functional impairment of the mucociliary apparatus.

The altered characteristics of sinus secretions also contribute to the pathogenesis of sinusitis. The mucous blanket in the respiratory tract is made up of two layers. The periciliary liquid phase is a thin, low-viscosity layer that surrounds the shaft of the cilia and allows the cilia to beat freely. The gel phase is a more viscous layer that rides on top of the periciliary liquid. Alterations in the mucous layer, which occur in the presence of inflammatory debris, as in an inflamed sinus, may further impair ciliary movement because cilia beat most efficiently in a low-viscosity environment.[11]

History and Physical

Patients with acute sinusitis present with symptoms that have been present for fewer than four weeks. Specific symptoms may include anterior or posterior nasal purulence, obstruction, hyposmia, anosmia, fever, facial pain or pressure, dental pain, fatigue, halitosis, and headache, among other complaints[9]. Patients with recurrent acute rhinosinusitis, by definition, will have had at least 4 of these episodes within the previous year and likely will have undergone multiple treatment regimens with nasal sprays, steroids, and/or antibiotics.

On physical exam, the healthcare provider may notice anterior or posterior purulent rhinorrhea, turbinate hypertrophy, mucosal congestion, or erythema on anterior rhinoscopy. There may be external tenderness to palpation of the frontal, ethmoid, or maxillary sinuses. The patient may be febrile or even tachycardic due to generalized facial pain. Although rare, some patients with acute sinusitis may present with complications such as orbital cellulitis, preseptal cellulitis, or cavernous sinus thrombosis.[12] Cranial nerve testing and close inspection of the orbit should be performed to rule out these complications.

Patients suffering from recurrent acute rhinosinusitis tend to manifest symptoms similar to acute sinusitis. An episode of acute sinusitis should be presumed to have a viral etiology if the patient reports fewer than ten days of symptoms.[1] Acute bacterial rhinosinusitis should be considered when symptoms last more than ten days or worsen within two days after initial improvement, also known as double worsening.[9] Most episodes of acute sinusitis, whether viral or bacterial in etiology, resolve within 10 to 14 days. 

Evaluation

History and physical examination are key to diagnosing recurrent acute rhinosinusitis. In most cases, a healthcare provider can make the correct diagnosis by considering the time course of symptoms and applying the major and minor diagnostic criteria set forth by the American Academy of Otolaryngology-Head and Neck Surgery.[13] Nasal endoscopy should be considered for patients with unilateral disease without septal deviation, patients with severe, disabling symptoms, and patients whose symptoms do not resolve with appropriate empirical treatment.[1]

Radiological imaging is not routinely recommended to evaluate patients with presumed uncomplicated recurrent acute sinusitis. A non-contrast CT scan of the sinuses is indicated for patients with chronic rhinosinusitis, suspected anatomical abnormalities, or possible orbital complications. A CT scan is a component of presurgical planning for balloon sinuplasty and functional endoscopic sinus surgery (FESS).[14] Research suggests that imaging is over-utilized for patients with sinusitis. According to one study, 11.4% of patients with uncomplicated recurrent acute rhinosinusitis received a CT scan within one year of diagnosis; the number increased to 39.9% at four years.[10]

Cultures obtained from sinus aspirates or endoscopy may be needed to identify resistant bacterial or fungal pathogens in cases of persistent or chronic sinusitis. The most frequent pathogens involved in recurrent acute rhinosinusitis are similar to those that cause acute sinusitis: Streptococcus pneumoniae, Haemophilus influenzae, other Streptococcus species, Moraxella catarrhalis, or Staphylococcus aureus.[4]

Treatment / Management

Medical management is the mainstay of treatment for recurrent acute rhinosinusitis. Many patients require a combination of therapies that target different components of the complex pathophysiology that leads to the development of RARS. These treatments are outlined below.

• Topical Intranasal Therapy
• • Nasal saline irrigation effectively removes or reduces the burden of debris and pathogens from the nares, which may provide symptomatic relief. Evidence is mixed regarding the efficacy of hypertonic versus isotonic saline solutions, but hypertonic saline causes more adverse effects such as increased nasal discharge and local discomfort.[15][16]
  • Topical corticosteroid nasal sprays reduce mucosal inflammation, thereby reducing stenosis of the sinus drainage pathways. 
  • Topical antihistamines such as azelastine can help reduce inflammation and irritation of the mucosa, reduce edema in the nasal passages, and open the sinus ostia. 
  • Topical decongestant sprays such as oxymetazoline or phenylephrine may help reduce congestion via local vasoconstriction. Patients should be cautioned regarding the rebound congestion that may accompany prolonged use of these decongestant sprays. The use of these medications should be limited to 3 to 5 days.[17]
• Antibiotics
• • Only 0.5% to 2% of cases of viral sinusitis are complicated by bacterial sinusitis.[16] Therefore, antibiotics therapy should be started only if the symptoms persist for more than ten days without improvement or if symptoms worsen after an initial period of improvement. 
  • Amoxicillin with or without clavulanate is the recommended initial antibiotic therapy for recurrent acute rhinosinusitis. Research indicates that amoxicillin is as effective as amoxicillin-clavulanate in treating acute sinusitis but causes fewer adverse gastrointestinal symptoms.[18] Alternatives for penicillin-allergic patients or resistant infections include doxycycline or a respiratory fluoroquinolone (levofloxacin, moxifloxacin). Other alternative antibiotics include a third-generation cephalosporin with or without clindamycin, depending on the specific clinical situation.[4] 
  • Intravenous antibiotics are the mainstay of treatment for patients with orbital cellulitis or moderate-to-severe preseptal cellulitis. Recommended antibiotics include vancomycin and ampicillin-sulbactam, clindamycin, a third-generation cephalosporin, or piperacillin-tazobactam.[19]  
• Decongestants
• • Oral decongestants provide symptomatic relief by reducing inflammation and secretions from the nasal, sinus, and respiratory tract mucosa. Oral decongestants may also help maintain patency of the nasal ostia, leading to a reduction of sinus pressure. 
• Oral Antihistamines
• • Oral antihistamines block the biologic histamine pathway that causes mucosal edema and inflammation when sensitized patients are exposed to inhaled allergens. They may be helpful for patients in whom sinusitis is thought to be precipitated or exacerbated by allergic rhinitis.[20]
• Oral Steroids
• • Oral steroids are not recommended as monotherapy for acute rhinosinusitis; there is limited evidence supporting oral steroids as an adjunct to antimicrobial therapy for acute sinusitis.[21]
• Oral Leukotriene modifiers
• • Leukotriene modifiers such as montelukast are effective treatments for allergic rhinitis and nasal polyposis. They may benefit patients with rhinosinusitis who also have asthma, allergic rhinitis, or nasal polyposis.[22]

Surgical intervention for recurrent acute rhinosinusitis can be considered for patients who do not respond to medical management, particularly if they have documented anatomic abnormalities that correlate with their symptoms. Surgery has been shown to decrease symptoms and improve the quality of life for appropriately-selected patients.[8][23][24] Surgical intervention is also often required for patients with sinusitis-related complications such as subperiosteal abscess, orbital abscess, or cavernous sinus thrombosis. Specific surgical approaches are discussed below.

Functional Endoscopic Sinus Surgery (FESS) can be employed to correct anatomic abnormalities that prevent optimal sinus drainage. A variety of procedures, including maxillary antrostomy, uncinate takedown, ethmoidectomy, Draf I-III, and/or saline washout, can be performed depending on the location and severity of the individual patient’s pathology. Non-contrast computed tomography of the sinuses should be performed before surgical intervention.[14]

Balloon sinuplasty is a tissue-sparing treatment used to permanently dilate the sinus ostia and sinus drainage pathways via local micro-fracturing with balloon insufflation. This allows for improved mucus drainage and reduced negative pressure in the sinus cavities. Balloon sinuplasty is used to treat patients with recurrent acute rhinosinusitis and chronic rhinosinusitis without nasal polyposis (CRSsNP).[23] This minimally-invasive procedure may be performed in an operating room or office setting. 

Septoplasty can be performed in patients with obstructive nasal septal deviations. The procedure reduces impingement of the sinus ostia, improves airflow, and facilitates proper mucociliary clearance.

Turbinate reduction may relieve nasal obstruction and allow further anterior drainage of nasal and sinus contents in patients with hypertrophy of the inferior turbinates. 

Differential Diagnosis

The clinical presentations of several disease processes overlap with the symptoms of recurrent acute rhinosinusitis. Other diseases and conditions that should be ruled out before making the diagnosis include:

• Allergic rhinosinusitis
• Acute rhinosinusitis
• Chronic rhinosinusitis with nasal polyposis (CRSwNP)
• Chronic rhinosinusitis without nasal polyposis (CRSsNP)
• Subacute rhinosinusitis
• Viral rhinosinusitis
• Cerebrospinal fluid (CSF) rhinorrhea
• Non-Invasive fungal rhinosinusitis
• Invasive fungal rhinosinusitis

Prognosis

The prognosis for recurrent acute rhinosinusitis is generally good. Most patients improve with medical management, including topical nasal sprays and oral antibiotics. Patients rarely develop complications requiring hospitalization for immediate surgical intervention or intravenous antibiotics. Appropriately selected patients who undergo surgery typically experience symptomatic relief and appreciable improvement in quality of life.[25][23][24] 

Complications

Although rare, complications of recurrent acute rhinosinusitis include but are not limited to the following:

• Preseptal cellulitis
• Orbital cellulitis
• Subperiosteal abscess
• Orbital abscess
• Cavernous sinus thrombosis

Consultations

Consultation with an ophthalmologist may be required for additional evaluation and management of orbital complications.

Deterrence and Patient Education

It is important to provide patient education regarding the expected natural history of symptoms, the strategies they should employ to manage symptoms at home, and the circumstances that should prompt them to seek additional medical care. This anticipatory guidance empowers patients to recognize and treat their symptoms earlier in the course of illness. Ideally, appropriate early management of symptoms will decrease the likelihood of symptom progression, thereby reducing the need for more aggressive and costly therapies. When patients require additional treatment, providing education about medication regimens, common adverse effects, and expected outcomes will help to increase patient satisfaction. 

Pearls and Other Issues

Points to remember:

• Recurrent sinusitis is a clinical diagnosis defined by four or more distinct episodes of sinusitis per year, with symptom-free intervals between episodes. 
• Diagnostic imaging is not recommended for uncomplicated acute recurrent sinusitis; however, a non-contrast CT scan may demonstrate anatomical obstruction in patients with recurrent acute sinusitis. 
• Symptomatic treatment with a trial of a decongestant nasal spray, daily intranasal irrigation, and/or a corticosteroid nasal spray is the mainstay of treatment during the first ten days of symptoms.
• A variety of antibiotics may be used to treat suspected bacterial sinusitis. The specific choice of medication should be based on local antibiograms, patient risk factors, allergies, and co-morbidities. Drug resistance should be considered in refractory cases.
• While medical therapy is the mainstay of treatment for most patients, research indicates that surgical intervention is beneficial for a subset of patients with recurrent acute rhinosinusitis. Outcomes are similar to those seen in patients surgically treated for chronic rhinosinusitis. 
• Endoscopic surgical techniques are particularly useful for patients with proven turbinate hypertrophy, conchae bullosa, stenosed sinus ostia, frontal sinus cells, Onodi cells, Haller cells, and septal spurs. 
• Balloon sinus dilation is a minimally invasive endoscopic approach that effectively treats both recurrent acute rhinosinusitis and chronic rhinosinusitis without nasal polyposis.
• Orbital complications of recurrent acute rhinosinusitis include preseptal cellulitis, orbital cellulitis, and cavernous sinus thrombosis. Physicians must remain vigilant in monitoring for the development of cranial nerve deficits or other signs of orbital involvement and provide immediate treatment to these patients.

Enhancing Healthcare Team Outcomes

Recurrent acute rhinosinusitis can be a frustrating condition for patients and providers. Because the condition, by definition, is recurrent, patients benefit from having a medical home in which a primary care provider can monitor their condition over time and coordinate care. Other interprofessional team members may include a combination of a general otolaryngologist, rhinologist, pharmacist, nurse, and in some cases, an ophthalmologist. Management must be tailored to each patient’s needs, as responses to specific treatments vary among individuals. Primary care and specialty providers are crucial to making diagnoses and formulating optimal treatment plans. Pharmacists ensure that medication selection and dosing are appropriate in the context of patient allergies and comorbidities. Nurses provide direct patient care and education and often facilitate communication between patients and physicians. Otolaryngologists, rhinologists, and ophthalmologists are often required to manage complications or perform surgical procedures when medical management fails. 

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Disclosure: Gyanendra Sharma declares no relevant financial relationships with ineligible companies.

Disclosure: Daniel Lofgren declares no relevant financial relationships with ineligible companies.

Disclosure: Henry Taliaferro declares no relevant financial relationships with ineligible companies.