Acute Rhinosinusitis


General Definitions

  • Rhinosinusitis is Defined as the Symptomatic Inflammation of Nasal Cavity and Paranasal Sinuses
    • Inflammation of the Sinuses Rarely Occurs without Concomitant Nasal Mucosal Inflammation

Definitions Based on Duration of Disease (Otolaryngol Head Neck Surg, 2015) [MEDLINE]

  • Acute Rhinosinusitis
    • Acute Rhinosinusitis is Defined as the Presence of Symptoms for <4 wks
    • The Most Common Etiology of Acute Sinusitis is Viral Infection Associated with the Common Cold (see Common Cold)
  • Subacute Rhinosinusitis
    • Subacute Rhinosinusitis is Defined as the Presence of Symptoms for 4-12 wks
  • Chronic Rhinosinusitis (see Chronic Rhinosinusitis)
    • Chronic Rhinosinusitis is Defined as the Presence of Symptoms for >12 wks
  • Recurrent Acute Rhinosinusitis
    • Recurrent Acute Rhinosinusitis is Defined as the ≥4 Episodes of Acute Rhinosinusitis Per Year (with Intervening Symptom Resolution)

Definitions Based on Etiology and Clinical Manifestations (Otolaryngol Head Neck Surg, 2015) [MEDLINE]

  • Acute Viral Rhinosinusitis
    • Acute Viral Rhinosinusitis is Defined as Acute Rhinosinusitis with a Viral Etiology
  • Uncomplicated Acute Bacterial Rhinosinusitis
    • Uncomplicated Acute Bacterial Rhinosinusitis is Defined as Acute Rhinosinusitis with bacterial etiology without clinical evidence of extension outside the paranasal sinuses and nasal cavity (eg, without neurologic, ophthalmologic, or soft tissue involvement)
  • Complicated Acute Bacterial Rhinosinusitis
    • Complicated Acute Bacterial Rhinosinusitis is Defined as Acute Rhinosinusitis with bacterial etiology with clinical evidence of extension outside the paranasal sinuses and nasal cavity



  • Annual Incidence of Acute Rhinosinusitis is Approximately 1 Case Per 7-8 Persons in the United States and Other Western Countries (Vital Health Stat, 2014) [MEDLINE]
    • Approximately 30 million Cases Per Year in the United States
    • Accounts for $3 billion in annual health care costs
    • Other costs include lost work productivity and impaired quality of life
  • Age: in adults, highest incidence occurs in the 45-64 y/o group
  • Sex: females > males

Risk Factors

Risk factors for ARS include older age, smoking, air travel, exposure to changes in atmospheric pressure (eg, deep sea diving), swimming, asthma and allergies, dental disease, and immunodeficiency (Ann Intern Med, 2010) [MEDLINE]




Community-Acquired Acute Bacterial Rhinosinusitis (Laryngoscope, 2010) [MEDLINE] (Otolaryngol Head Neck Surg, 2015) [MEDLINE]

  • General Comments
    • Acute Bacterial Infection Occurs in Only 0.5-2% of Acute Rhinosinusitis Cases (Rhinology, 2007) [MEDLINE]
    • Organisms Which are Considered Normal Upper Respiratory Tract Flora
    • Most Cases are Monomicrobial
      • Monomicrobial: 75% of cases
      • Two Microbes Isolated: 25% of cases
  • Anerobes
    • Risk Factor
      • Dental Root Infection with Sinus Invasion
  • Haemophilus Influenzae (see Haemophilus Influenzae)
    • Epidemiology
      • Haemophilus Influenzae Accounts for 22-36% of Cases
  • Moraxella Catarrhalis (see Moraxella Catarrhalis)
    • Epidemiology
      • Moraxella Catarrhalis Accounts for 2-16% of Cases
  • Staphylococcus Aureus (see Staphylococcus Aureus)
    • Epidemiology
      • Staphylococcus Aureus Accounts for 10-13% of Cases
  • Streptococcus Pneumoniae (see Streptococcus)
    • Epidemiology
      • Streptococcus Pneumoniae Accounts for 20-43% of Cases
  • Streptococcus Pyogenes (Group A Beta Hemolytic Streptococcus) (see Streptococcus Pyogenes)
    • Epidemiology
      • Streptococcus Pyogenes Accounts for 3% of cases

Hospital-Acquired Acute Bacterial Rhinosinusitis




Upper Respiratory Tract

  • Components of the Upper Respiratory Tract: generally, refers to the parts of the respiratory system above the vocal cords
    • Nose and Nasal Cavity
    • Mouth and Oral Cavity
    • Pharynx
    • Larynx: connects the upper respiratory tract to the trachea (trachea is the first part of the lower respiratory tract)
      • Contains the Vocal Cords

Lower Respiratory Tract

  • Derived from the Developing Foregut
  • Components of the Lower Respiratory Tract
    • Lower Part of Larynx
    • Trachea
    • Bronchi (Primary, Secondary, and Tertiary)
    • Bronchioles (Including Terminal and Respiratory Bornchioles)
    • Alveoli

Acute Viral Rhinosinusitis

  • Direct Contact with Viral Inoculation of Conjunctiva and/or Nasal Mucosa
    • Rapid viral replication in non-immune patient (with detectable viral levels within the viral mucosa within 8-10 hrs): symptoms usually develop within the first day after inoculation
    • Spread to paranasal sinuses by systemic or direct transmission: nose blowing may facilitate propulsion of contaminated fluid from nasal mucosa into the paranasal sinuses
    • Sinonasal hypersecretion, increased vascular permeability, and transudation of fluid into the nasal cavity and sinuses
    • Direct toxic effect of virus on nasal cilia -> impairs mucociliary clearance
    • Mucosal edema, thickened secretions, and ciliary dyskinesia -> sinus obstruction and perpetuation of the disease process

Acute Bacterial Rhinosinusitis

  • Bacteria Secondarily Infect an Inflamed Sinus Cavity
    • Etiologies of Inflamed Nasal Cavity
      • Allergic Rhinitis (see Allergic Rhinitis)
      • Impaired Mucociliary Clearance
      • Immunodeficiency
      • Impairment of Sinus Drainage
      • Intranasal Cocaine Abuse
      • Mechanical Nasal Obstruction
      • Odontogenic Infection (Dental Abscess)
      • Preceding Viral Rhinosinusitis
      • Swimming


  • Rhinoscopy
    • May demonstrate mucosal edema, narrowing of middle meatus, hypertrophy of the inferior turbinate, rhinorrhea, or purulent nasal discharge
  • Transillumination of Sinuses: limited diagnostic utility -> not recommended
  • Culture of Nasal Discharge or Swabs
    • Viral Culture: not indicated
    • Bacterial Culture: not generally utilized (since empiric therapy is usually adequate in the primary care setting)
  • Sinus Endoscopy: usually safely performed in otolaryngologist office
    • Indications for Endoscopic Culture of Middle Meatal Specimen
      • Cystic Fibrosis
      • Hospital-Acquired Rhinosinusitis
      • Immunocompromised Patient: especially if mucormycosis is suspected
      • Lack of Response to Antibiotic Therapy
      • Recent Hospitalization
      • Suspicion of Intracranial Extension: with vision changes, severe headache, peri-orbital edema, or alteration in mental status
  • Antral Sinus Puncture: no longer required
  • Sinus Computed Tomography (CT): imaging procedure of choice (when indicated)
    • Not indicated in the initial evaluation of uncomplicated acute rhinosinusitis
    • Sinus CT may be useful in ruling out acute rhinosinusitis, when other diagnoses are a consideration
    • Indications for Imaging
      • Recurrent/Treatment-Resistant Rhinosinusitis: to diagnose blockage of the ostio-meatal complex -> in this case, no contrast is required
      • Suspicion of Orbital/Intracranial Extension: with vision changes, severe headache, peri-orbital edema, or alteration in mental status -> in this case, contrast is required
    • Findings
      • Air Bubbles within the Sinuses
      • Sinus Air-Fluid Levels
      • Sinus Mucosal Edema
        • However, some form of sinus mucosal abnormality can be identified on CT in 42% of asymptomatic healthy persons
        • In patient with common cold, 87% manifested sinus air-fluid levels and/or mucosal thickening when assessed within 2-3 days of symptom onset
  • Sinus Magnetic Resonance Imaging (MRI): useful for patients with suspected extra-sinus extension

Clinical Differentiation of Upper Respiratory Tract Infection vs Lower Respiratory Tract Infection

Clinical Manifestations (J Allergy Clin Immunol, 2004) [MEDLINE] (Clin Infect Dis, 2012) [MEDLINE]

General Comments

  • In General, the Clinical Presentation Has Limited Accuracy in Differentiating Acute Viral Rhinosinusitis from Acute Bacterial Rhinosinusitis (Lancet, 2008) [MEDLINE] (Clin Infect Dis, 2012) [MEDLINE]
  • Clinical Features Suggesting the Diagnosis of Acute Bacterial Rhinosinusitis (Over Acute Viral Rhinosinusitis) (Per the Infectious Disease Society of America, IDSA 2012 Guidelines; Criteria Have Not Been Rigorously Evaluated) (Clin Infect Dis, 2012) [MEDLINE]
    • Persistent Symptoms of Acute Rhinosinusitis (Nasal Discharge/Fever/Headache/Facial Pain) Lasting at Least 10 Days without Evidence of Clinical Improvement
      • Although Viral Symptoms May Persist for >10 Days in Some Cases, There is Generally Some Clinical Improvement by Day 10
      • However, in Trials, Only 60% of Adults with Symptoms for >7-10 Days Had a Bacterial Etiology Identified by Sinus Aspirate
    • Onset of Severe Symptoms or High Fever (>39 degrees C/102 degrees F) and Purulent Nasal Discharge/Facial Pain at Least 3-4 Consecutive Days at the Beginning of the Illness
      • Fever Associated with Viral Rhinosinusitis Usually Subsides in 24-48 hrs
      • Purulent Nasal Discharge Associated with Viral Rhinosinusitis Usually Occurs 4-5 Days into the Illness
    • “Double-Sickening Pattern”
      • Onset of Worsening Symptoms/Signs (New Onset of Fever/Headache/Nasal Discharge) Following a Typical Viral Upper Respiratory Infection that Lasted 5-6 Days and Was Initially Improving

Otolaryngologic Manifestations

  • Dental Pain (see Dental Pain)
  • Eustachian Tube Dysfunction Clinical Ear Pain/Fullness/Pressure (see Ear Pain) Hearing Loss (see Hearing Loss) Tinnitus (see Tinnitus)
  • Facial Pain/Pressure/Congestion/Fullness
    • Worse with Bending Forward (this maneuver may be more sensitive than attempting to provoke by direct sinus percussion)
  • Fatigue (see Fatigue)
  • Halitosis (see Halitosis)
  • Nasal Congestion/Obstruction (see Nasal Congestion)
  • Purulent Anterior Nasal Discharge (see Nasal Discharge)
  • Purulent or Discolored Posterior Nasal Discharge(see Nasal Discharge)
  • Hyposmia/Anosmia (see Anosmia)

Neurologic Manifestations

Pulmonary Manifestations

  • Cough (see Cough)
    • Clinical
      • XXXX

Other Manifestations

  • Fever (see Fever)
    • Clinical
      • May Be the Only Sign in Hospital-Acquired Cases

Natural Course of Disease

Acute Viral Rhinosinusitis

  • xxxx

Acute Bacterial Rhinosinusitis

  • xxxx

Complications of Acute Bacterial Rhinosinusitis

  • Anosmia (Permanent) (see Anosmia)
  • Chronic Rhinosinusitis (see Chronic Rhinosinusitis): however, the relationship between acute rhinosinusitis and its potential for progression to chronic rhinosinusitis has not been well studied
  • Intracranial Epidural Abscess (see Intracranial Epidural Abscess): may be manifested by alteration in mental status, diplopia//vision changes
  • Meningitis (see Meningitis)
  • Orbital Abscess/Cellulitis: manifested by peri-orbital edema
  • Sinus Bone Osteomyelitis



Saline Irrigation

  • Mechanical Irrigation with Sterile Buffered/Physiologic/Hypertonic Saline: may decreased the need for analgesics and improve overall patient comfort (especially in patients with frequent sinus infections)
    • Use of tap water is contraindicated (due to risk of amebic encephalitis)

Removal of Nasal Devices

  • Removal of Nasogastric Tubes/Removal of Nasal Packing/Avoidance of Nasaotracheal Intubation: indicated in hospital-acquired cases

Topical Ipratropium Bromide (see Ipratropium Bromide)

  • Pharmacology: minimally absorbed across biologic membranes
  • Clinical Effects
    • Decreases Rhinorrhea in Viral Rhinosinusitis: likely due to an effect on parasympathetic regulation of mucous and seromucous glands

Topical Decongestants

  • Agents
  • Use
    • Use sparingly (no more than 3 consecutive days) to avoid rebound nasal congestion
    • May be useful for symptomatic relief in acute viral rhinosinusitis
    • Little benefit as an adjunctive therapy to antibiotics in acute bacterial rhinosinusitis

Oral Decongestants

  • Agents
    • Ephedrine (see Ephedrine)
    • Phenylephrine (Neosynephrine) (see Phenylephrine)
    • Phenylpropanolamine (xxx) (see Phenylpropanolamine): associated with an increased risk of hemorrhagic cerebrovascular accident (CVA)
    • Pseudoephedrine (Sudafed) (see Pseudoephedrine): improves nasal airflow in viral rhinosinusitis
  • Recommendations
    • May be beneficial to decrease mucosal edema, facilitate aeration, and promote nasal drainage in acute viral rhinosinusitis: when eustachian tube dysfunction is present, a 3-5 day course or oral decongestants may be indicated
    • Little benefit as an adjunctive therapy to antibiotics in acute bacterial rhinosinusitis

Topical Corticosteroids (see Corticosteroids)

  • Rationale: corticosteroids decrease mucosal inflammation, improving sinus drainage
  • Clinical Efficacy: many studies are not well-controlled for disease process and treatment regimens
    • Meta-Analysis (2013): topical corticosteroids increase rate of symptom response (when used with or without concomitant antibiotics), as compared to placebo [MEDLINE]
  • Recommendations: greatest benefit is likely to occur in patients with underlying allergic rhinitis

Systemic Corticosteroids (see Corticosteroids)

  • Clinical Efficacy
    • Systemic Review/Meta-Analysis (2011) [MEDLINE]: n = 4 randomized trials -> systemic corticosteroids with antibiotics improved symptom control at days 3-7, as compared to antibiotics with placebo (or in one trial, a non-steroidal anti-inflammatory)
    • Randomized Trial (2012) [MEDLINE]: systemic corticosteroids had no clinical benefit
  • Recommendations: not recommended until further high-quality trials are performed


  • Rationale: mucosal drying effect (although this effect may worsen symptoms)
  • Recommendations: no trials support their clinical efficacy -> not recommended


  • Rationale: thin secretions and may facilitate mucous drainage
  • Agents
  • Recommendations: no trials support their clinical efficacy


Determination of Need for Antibiotics

  • Inappropriate Antibiotic Use: due to the difficulty distinguishing viral from bacterial acute rhinosinusitis, inappropriate antibiotic use has historically been common
    • In the US, 85-98% of patients receive antibiotics for upper respiratory or sinus infection (despite the vast majority of these representing viral rhinosinusitis, for which antibiotics are ineffective) [MEDLINE]

Data Supporting Efficacy of Antibiotics

  • Clinical Efficacy
    • Systematic Review of 10 Trials in Patients with Uncomplicated Acute Sinusitis and Normal Immune System (2012): antibiotics slightly shortened the time to cure, but increased the incidence of adverse effects [MEDLINE]
  • Recommendations
    • Antibiotics are Indicated in Acute Bacterial Rhinosinusitis to Eliminate Infection and Decrease the Risk of Complications


  • Amoxicillin-Clavulinic Acid (Augmentin) (see Amoxicillin-Clavulanic Acid): preferred first-line empiric agent
    • Dose: 500 mg/125 mg PO TID or 875 mg/125 mg PO BID
    • Indications for High-Dose Amoxacillin-Clavulanic Acid (2 g PO BID)
      • Age 65 y/o and Older
      • Immunocompromised
      • Recently Hospitalized
      • Residence in Geographic Region where Streptococcus Pneumoniae Have Penicillin-Resistance Rates >10%
      • Treated with Antibiotic in Previous Month
    • Pregnancy: Amoxacillin-Clavulinic Acid is class B -> acceptable
  • Doxycycline (see Doxycycline): appropriate alternative agent
    • Pregnancy: contraindicated
  • Levofloxacin/Moxifloxacin (see Levofloxacin and Moxifloxacin): appropriate alternative agent
    • Pregnancy: fluoroquinolones are contraindicated
  • Macrolides (Clarithromycin/Azithromycin)/Trimethoprim-Sulfamethoxazole/Second or Third-Generation Cephalosporins: not recommended for empiric therapy due to high rates of Streptococcus Pneumoniae resistance (and high rates of Haemophilus Influenzae resistance to Trimethoprim-Sulfamethoxazole)
    • Azithromycin would be acceptable alternative in a pregnant patient with penicillin allergy
  • Routine Coverage for Staphylococcus Aureus (Methicillin-Sensitive or Methicillin-Resistant): not recommended

Duration of Antibiotic Therapy

  • IDSA Guidelines [MEDLINE]: 5-7 day course (rather than 10-14 day course) is recommended in adults
    • Meta-Analysis (2009) [MEDLINE]: n = 12 randomized trials -> there was no difference in response/relapse rates between short courses (3-7 days) vs longer courses (6-10 days) of antibiotics

Treatment Failure

  • Expected Course of Clinical Improvement on Antibiotics: patients with acute bacterial rhinosinusitis are expected to demonstrate response to empiric antibiotics within 3-5 days
    • Experimental evidence indicates bacterial eradication by day three: studies have correlated clinical and bacteriologic response
  • Reasons for Treatment Failure
    • Inadequate Antibiotic Dosing
    • Non-Infectious Etiology
    • Resistant Pathogen
    • Structural Abnormality
  • Recommendations
    • Ideally, an endoscopically-guided culture could be performed to redirect antibiotic therapy (note: nasopharyngeal cultures are not reliable)
    • Total course duration of 7-10 days is recommended
    • CT scan of the sinuses is indicated if symptoms worsen or fail to improve
  • Second-Line Agents

Relapse After Treatment

  • Recurrence Within 2 wks of Response to Initial Treatment: usually represents inadequate eradication of infection
    • Patients with good response to initial therapy and who have mild symptoms of relapse: treat with a longer course of the same antibiotic
    • Patients who had only minimal symptom response with the initial antibiotic or whose relapse is moderate to severe: more likely to have organisms resistant to the initial empiric antibiotic and require a change in antibiotic

Indications for ENT Referral

  • Patients with Suspected Extra-Sinus SpreadL characterized by high/persistent fevers, meningeal signs, visual disturbance, orbital edema, severe headache, or altered mental status
  • Patients with Suspected Mucormycosis: patients require urgent endoscopy or surgical biopsy
  • Patients with Hospital-Acquired Acute Bacterial Rhinosinusitis
  • Patients with Identified Structural Defects
  • Patient with Lack of Response to First/Second-Line Therapy
  • Multiple Recurrent Episodes of Acute Bacterial Rhinosinusitis (3-4 episodes per year)
  • Chronic Rhinosinusitis (with or without Polyps or Asthma) with Recurrent Exacerbations of Acute Bacterial Rhinosinusitis
  • Patients with Allergic Rhinitis who May be Candidates for Immunotherapy




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