SUMMARY:

Rhinosinusitis is inflammation of the paranasal sinuses and nasal cavity. It can result from viral, bacterial, or fungal infections with viral being the most common. Infection extension beyond the sinuses and cavities can result in bacterial rhinosinusitis complications (i.e, periorbital edema, meningitis). Sinusitis affects 1 in 8 adults in the United States and accounts for more outpatient antibiotic prescriptions than any other diagnosis. Sinusitis can be further categorized as acute, subacute, chronic, and recurrent based on symptom duration. Whether viral or bacterial, most cases of uncomplicated acute rhinosinusitis self-resolve with supportive care alone but antibiotic therapy should be considered in certain cases of acute bacterial rhinosinusitis.

Symptoms and Classification of Sinusitis

Cardinal symptoms of Acute Rhinosinusitis (ARS)

• Purulent nasal discharge

and

• Nasal obstruction/congestion

or

• Facial pain/pressure/fullness/headache

Additional symptoms

• Fever
• Fatigue
• Cough
• Headache
• Decreased sense of smell
• Maxillary dental pain
• Ear pain/pressure/fullness

Note: ARS is a clinical diagnosis based on the presence of cardinal symptoms. Imaging is not needed. Distinguishing between a viral or bacterial infection is based more on duration and course of symptomatology. Color of nasal discharge alone has poor predictability for predicting the likelihood of a bacterial sinus infection.

Classification

• Acute (less than 4 weeks)
• Subacute (4 to 12 weeks)
• Chronic (>12 weeks)
• Recurrent (four episodes lasting <4 weeks with complete symptoms resolution between episodes)

Risk Factors

• Smoking
• Exposure to changes in atmospheric pressure
  • Air travel | Deep sea diving
• Swimming
• Asthma and allergies
• Preceding viral upper respiratory infection
• Dental disease
• Immunodeficiency
• Older age
• Sinus surgeries
• Mechanical obstruction
  • Deviated nasal septum, nasal polyps, tumor, foreign body, trauma

Differential Diagnosis

• Nasal foreign body
• Structural abnormalities
  • Deviated septum | Neoplasm | Septal perforations from cocaine use
• The common cold
• Noninfectious rhinitis
  • Allergic rhinitis | Nonallergic vasomotor rhinitis
• Headaches
  • Migraines | Tension | Cluster
• Neuralgias
• Temporomandibular joint disorder
• Dental disease

Complicated Acute Bacterial Rhinosinusitis

Complications of bacterial sinusitis occur when infection spreads beyond the nasal sinuses into surrounding areas including the central nervous system, orbits, and adjacent tissue spaces

• Pre-septal (periorbital) cellulitis
• Orbital cellulitis
  • Ocular pain | Eyelid swelling | Pain with eye movements | Proptosis | Diplopia
• Subperiosteal abscess
  • Marked displacement of globe
• Osteomyelitis of sinus bones
• Meningitis
  • Fevers | Nuchal rigidity | Mental changes
• Intracranial abscess
  • Headache unrelieved with analgesics
• Septic cavernous sinus thrombosis
  • Cranial nerve palsies

Note: Consider imaging with urgent referral to specialist or immediate emergency department evaluation if signs of systemic toxicity, peri-orbital involvement, meningeal symptoms, or concern for invasive fungal infection

Risk factors for Complications from ABRS

• High endemic rates of penicillin resistant S. Pneumoniae (>10%)
• Extremes of age: <2 years old or >65 years old
• Hospitalization in past 5 days
• Daycare attendance
• Healthcare occupation
• Antibiotic use in past month
• Immunocompromised
• Multiple comorbidities
• Evidence of systemic toxicity

Treatment

First determine if viral or bacterial etiology

• This helps prevent unnecessary treatment with antibiotics
• Acute bacterial rhinosinusitis (ABRS) can be differentiated from acute viral rhinosinusitis (AVRS) by evidence of one of the following
  • Symptoms that persist >10 days without improvement has probability of bacterial rhinosinusitis of 60%
  • “Double worsening” | Worsening of symptoms (e.g., new onset of fever, headache, or increased nasal discharge) within first 10 days after initial improvement
  • Severe infection i.e., high fever >102 °F, purulent nasal discharge or facial pain that lasts for 3 to 4 consecutive days at beginning of illness

If Acute Viral Rhinosinusitis offer supportive care

• Most patients improve with symptomatic treatment alone
  • Analgesics | Antipyretics | Nasal saline irrigation | Intranasal glucocorticoids
  • Not recommended: Topical or oral decongestants and antihistamines
• If symptoms not improved after 10 days or has “double worsening” bacterial infection is likely

If Acute Bacterial Rhinosinusitis offer antibiotic therapy or period of ‘watchful waiting’ in conjunction with supportive care

• Watchful waiting: Observation period (without antibiotics) for 7 days from time of diagnosis of ARBS
• Systematic reviews (2014 & 2018)
  • Pro: High rates of resolution without antibiotic therapy within two weeks and less adverse events reported compared to placebo or no treatment
  • Con: Less cases of clinical failure with antibiotic treatment

When to initiate antibiotics

• If symptoms worsen during “watchful waiting” initiate antibiotic therapy
  • High fever >101 °F
  • Immunocompromised patients
• Patients with poor follow up are not good candidates for “watchful waiting”

Antibiotic Therapy

• Typical duration of treatment is 5 to 10 days
  • Meta-analysis studies | No difference in response rate for short course (3 to 7 days) vs. longer course (6 to 10 days) | Lower rate of adverse events with 5 vs 10-day courses
• First line antibiotic
  • Amoxicillin with or without clavulanate (500mg/125mg TID or 875mg/125mg BID)
• If high risk of bacterial resistance or poor outcome
  • Use high dose Augmentin 2g ER BID (amoxicillin 2g with clavulanate BID)
• If Penicillin allergy
  • Doxycycline | Clindamycin plus third generation cephalosporin | Respiratory fluoroquinolone (Note: last resort given FDA warning; see ‘Learn More – Primary Sources’ below)
• Treatment failure occurs when symptoms worsen or fail to improve within 7 days of antibiotic therapy
  • Switch antibiotic class
  • Evaluate for complications

Referral Indications

• Consider referral to otolaryngologist or allergist in the following cases
  • Development of complications
  • Patients who are seriously ill and immunocompromised
  • Refractory cases
  • Recurrent cases

Primary Sources – Learn More:

AAFP: Clinical Practice Guideline Update: Adult Sinusitis

Clinical Practice Guideline Update: Adult Sinusitis from American Academy of Otolaryngology–Head and Neck Surgery Foundation

Cochrane Systematic Review – Antibiotics for Acute Rhinosinusitis in Adults

FDA Fluoroquinolone Warning