SINUSITIS

• ACRONYMS AND DEFINITIONS

• AAP - American Academy of Pediatrics
• AAO-HNS - American Academy of Otolaryngology-Head and Neck Surgery
• IDSA- Infectious Diseases Society of America
• RCT - Randomized controlled trial

• PATHOLOGY

• Sinuses are hollow cavities in the bones around the nose (see sinus illustration). The cavities have ostia which are openings that continuously drain mucus into the nasal cavity. Ethmoid and maxillary sinuses are present at birth, but they are very small. As a person grows, they gradually enlarge and reach their full size in the teenage years. Frontal sinuses do not develop until around the age of 7 years, and they are not visible radiographically until the age of 12. The sphenoid sinus does not appear until adolescence.
• Sinusitis occurs when inflammation from an upper respiratory pathogen, allergies, or some other irritant causes the nasal mucosa to swell. The swollen mucosa blocks the ostia that drain the sinus cavities, and this leads to mucous retention and infection. The maxillary and ethmoid sinuses are most commonly affected.
• Viruses are by far the most common cause of sinusitis. About 0.5% - 2% of viral sinusitis infections will be complicated by bacterial sinusitis. The most common pathogens seen in acute bacterial sinusitis are Strep pneumoniae and Haemophilus influenzae.
• Sinusitis is one of the most common diagnoses in primary care, and it accounts for about 17 million antibiotic prescriptions each year in the U.S alone [1,2,9]

• RISK FACTORS

• Viral infections
• Allergic rhinitis
• Anatomical abnormalities - (ex. deviated septum, enlarged nasal tissue, etc.)
• Cigarette smoking
• Diabetes
• Swimming and diving
• High altitude climbing
• Dental infections and procedures

• SYMPTOMS

• Nasal obstruction or congestion
• Loss of sense of smell and taste
• Facial pain and tenderness
• Facial pain or pressure that is worse when leaning over
• Nasal drainage (anterior and/or posterior)
• NOTE: Nasal purulence or colored nasal discharge does not indicate a bacterial infection. Purulence and/or color are indicative of inflammation and the presence of neutrophils and are not specific for bacteria.
• Fever
• Toothache (upper teeth) [1,2,7]

• DIAGNOSIS

• The diagnosis of sinusitis is typically made based on clinical symptoms
• Diagnostic studies can be performed (see imaging below), but they are not generally performed in most clinical settings

• BACTERIAL VS VIRAL SINUSITIS

• Overview
• There is no single symptom or physical finding that can distinguish bacterial sinusitis from viral sinusitis
• The IDSA and the AAO-HNS guidelines give the following recommendations for distinguishing viral from bacterial sinusitis


• IDSA guidelines state the following characteristics may be more consistent with bacterial sinusitis:
• Persistent symptoms lasting ≥ 10 days without evidence of improvement
• Onset with severe symptoms or signs of high fever (102°F) and purulent nasal discharge or facial pain lasting for at least 3 – 4 consecutive days at the beginning of illness
• Onset with worsening symptoms or signs characterized by the new onset of fever, headache, or increase in nasal discharge following a typical viral upper respiratory infection that lasted 5–6 days and was initially improving. [3]


• AAO-HNS guidelines state that bacterial sinusitis should be diagnosed when:
• Symptoms or signs of acute rhinosinusitis (purulent nasal drainage accompanied by nasal obstruction, facial pain-pressure-fullness, or both) persist without evidence of improvement for at least 10 days beyond the onset of upper respiratory symptoms; OR
• Symptoms or signs of acute rhinosinusitis worsen within 10 days after an initial improvement (double worsening) [7]

• IMAGING

• Overview
• Imaging studies are not indicated in acute, uncomplicated sinusitis
• Imaging studies cannot distinguish between bacterial and viral sinusitis


• Imaging studies
• Sinus X-ray - X-rays may show sinus opacities, air-fluid levels, or marked mucosal thickening
• Sinus CT scan - CT scans provide a detailed view of the paranasal sinuses. One limitation of sinus CT scans is that there is a high frequency of abnormal scans in asymptomatic patients. [2]

• TREATMENT

• Sinusitis without signs of bacterial infection
• Treatment is symptomatic. See symptomatic treatment below


• Sinusitis with signs of bacterial infection
• The IDSA recommendations for antibiotic therapy in adults with symptoms of bacterial sinusitis (see bacterial vs viral) are outlined in the table below. The use of antibiotics in the treatment of sinusitis is controversial and largely unsupported by randomized controlled trials (see studies below).
• AAP recommendations for antibiotics in children with sinusitis are also presented below

• Symptomatic treatments
• Analgesics - medications like NSAIDs (e.g. ibuprofen, naproxen) and acetaminophen can be used for pain and fever
• Intranasal steroids (e.g. Flonase, Nasonex) - intranasal steroids help relieve facial pain and nasal congestion. In one study, intranasal steroid was superior to amoxicillin and placebo for symptom relief [PMID 16337461]. A Cochrane meta-analysis also found that intranasal steroids were effective in relieving symptoms of sinusitis. [PMID 24293353] Contrarily, a randomized controlled trial detailed below (see studies) found no effect.
• Sinus rinses (e.g. NeilMed, Neti Pot) - sinus rinses with either isotonic or hypertonic saline may help relieve symptoms of congestion, particularly in patients with recurrent sinusitis
• Oral decongestants (e.g. Sudafed) - oral decongestants can help alleviate congestive symptoms
• Topical decongestants (e.g. Afrin) - topical decongestants can help alleviate congestive symptoms. Limit use to 3 - 5 days to prevent rebound congestion.
• Oral antihistamines (e.g. Claritin, Allegra, Zyrtec) - oral antihistamines may decrease secretions and suppress sneezing
• Guaifenesin (expectorant) and dextromethorphan (cough suppressant) (e.g. Mucinex DM, Robitussin DM) - can suppress cough and loosen chest congestion

• Systemic steroids
• Systemic steroids (e.g. prednisone) are sometimes used to treat sinusitis. A Cochrane review of systemic steroids for acute sinusitis found that they may improve symptoms in the short-term (3 - 14 days). [PMID 24664368] The analysis was limited by the fact that 4 of the 5 trials used antibiotics in addition to steroids. The one trial (see studies below) that compared steroid monotherapy to placebo found no significant effect. The study used a lower dose of prednisolone (30 mg) which may have limited its effectiveness. [8]

• CHRONIC SINUSITIS

• Definition
• Acute sinusitis: < 4 weeks
• Subacute sinusitis: 4 - 12 weeks
• Chronic sinusitis: > 12 weeks

• Diagnosis
• The AAO-HNS 2015 sinusitis guidelines give two criteria for diagnosing chronic sinusitis
• Both criteria must be met to make a diagnosis


• Criteria 1: ≥ 12 weeks of ≥ 2 of the following signs or symptoms:
• Mucopurulent drainage (anterior, posterior, or both)
• Nasal obstruction (congestion)
• Facial pain, pressure, or fullness
• Decreased sense of smell
• Criteria 2: Inflammation documented by ≥ 1 of the following findings:
• Purulent (not clear) mucus or edema in the middle meatus or anterior ethmoid region
• Polyps in nasal cavity or the middle meatus
• Radiographic imaging (CT scan is preferred) showing inflammation of the paranasal sinuses
• Special considerations:
• Allergy testing - allergic rhinitis is present in 40 - 84% of patients with chronic sinusitis
• Immune function testing - immune deficiencies associated with chronic sinusitis include selective IgA deficiency, common variable immunodeficiency, and specific antibody deficiency which features normal IgG levels but a defective response to polysaccharide vaccines. Recommended immune testing may include quantitative immunoglobulin measurements (IgG, IgA, and IgM), preimmunization- and postimmunization-specific antibody responses to tetanus toxoid and pneumococcal polysaccharide vaccines, CH50, and measurement of T-cell number and function (delayed hypersensitivity skin tests and flow cytometric enumeration of T cells) [7]

• Treatment
• One or both of the following
• Daily intranasal steroids (e.g. Flonase, Nasonex)
• Daily saline nasal irrigation (e.g. NeilMed, Neti Pot)

• ANTIBIOTIC STUDIES

• STEROID STUDIES

• BIBLIOGRAPHY

• 1 - PMID 17303885 - BMJ review
• 2 - PMID 15329428 - NEJM review
• 3 - PMID 22438350 - IDSA guidelines
• 4 - PMID 23796742 - AAP sinusitis GL
• 5 - Manufacturer's PI for listed drug
• 6 - PMID 27431306 Neti pot study
• 7 - PMID 25832968 - AAO-HNS Clinical Practice Guideline (Update): Adult Sinusitis (2015)
• 8 - PMID 24664368 - Systemic corticosteroids for acute sinusitis, Cochrane Database Syst Rev (2014)
• 9 - Acute sinusitis, Medscape