Rhinosinusitis

See Also

Epidemiology

Incidence: 31 Million cases per year in U.S.
1. United States clinic office visits: 1%
2. Incidence: 14% annually in adults (25% lifetime Incidence)
3. Fifth most common indication for Antibiotic prescription in the U.S.
Sinuses affected
1. Maxillary Sinus
  1. Most commonly infected in adults
2. Frontal Sinus
  1. Next most commonly infected in adults
  2. Absent in 10% population and very young children
  3. Higher risk for intracranial spread
3. Ethmoid Sinus
  1. Most commonly infected in children
4. Sphenoid Sinus
  1. Isolated infection is rare
  2. Higher risk for intracranial spread

Pathophysiology

Background
1. Viral Upper Respiratory Infections involve sinuses in 90% of cases
2. Less than 1% of Upper Respiratory Infections evolve into documented Sinusitis
  1. Less than 10% of these documented Sinusitis cases are due to Bacterial superinfection
Initial
1. Mucosal inflammation of Paranasal Sinuses and nasal mucosa
  1. Nasal mucosa and sinus mucosa are contiguous and typically co-inflamed
2. Sinus ostia irritation and edema
3. Ciliary transport impaired by infection results in stasis of mucous
Next
1. Sinus ostia obstruction and stasis
2. Subsequent sinus infection

Types

Acute Sinusitis
1. Symptoms as long as 4 weeks
2. Further subdivided into Bacterial or viral
Subacute Sinusitis
1. Symptoms persist between 4 to 12 weeks
Chronic Sinusitis
1. Persistent Symptoms beyond 12 weeks
Recurrent Sinusitis
1. Four or more episodes per year
2. Each episode lasts 7 days or more
3. Symptom free intervals last greater than 2 months

Risk Factors

Ciliary Disorder
1. Tobacco use or smoke exposure
2. Cystic Fibrosis
3. Kartagener Syndrome (primary ciliary Dyskinesia)
Mechanical obstruction
1. Nasal Polyps
2. Septal deviation
3. Hypertrophic middle turbinates or concha bullosa
4. Nasal Foreign Body
5. Inflammatory disorder
  1. Granulomatosis with Polyangiitis (previously known as Wegener's Granulomatosis)
  2. Sarcoidosis
Mucosal edema and inflammation
1. Preceding Upper Respiratory Infection or recurrent Upper Respiratory Infection
2. Vasomotor Rhinitis
3. Allergic Rhinitis and other hyperreactivity
  1. Allergens (e.g. pollens, molds, animal dander)
  2. Air pollutants
4. Nonallergic (Samter's Triad)
  1. Asthma
  2. Nasal Polyps
  3. Aspirin sensitivity
Iatrogenic causes
1. Dental Infections and procedures
2. Sinus Surgery
3. Nasogastric Tubes
4. Nasal Packing (e.g. Epistaxis)
5. Mechanical Ventilation
Immune disorder (predisposes to prolonged course, recurrence, fungal and other atypical infections)
1. AIDS
2. Congenital Hypogammaglobulinemia (IgA or IgG subclass deficiency)
3. Post-Transplant with Immunosuppression
4. Chemotherapy
5. Diabetes Mellitus
6. Chronic Corticosteroid use

Etiology

Viral (most cases, 90 to 98% of all Rhinosinusitis)
1. Rhinovirus (most common viral Sinusitis cause)
2. Influenza
3. Parainfluenza
4. Adenovirus
Bacterial (superinfection of up to 2% of viral Upper Respiratory Infections)
1. Acute Sinusitis
2. Chronic Sinusitis
  1. Anaerobes (>50%)
    1. Bacteroides
    2. Anaerobic Gram Positive Cocci
    3. Fusobacterium species
  2. Other less common causes
    1. Hemophilus Influenzae
    2. Pseudomonas aeruginosa
    3. Escherichia coli
    4. Beta-hemolytic Streptococcus (e.g. Streptococcus Pyogenes)
    5. Neisseria causes
    6. Staphylococcus aureus
      1. Not considered a significant cause of acute uncomplicated Sinusitis
Fungal (Immunocompromised or Diabetes Mellitus)
1. Aspergillus
2. Mucormycosis
3. Fungus

Symptoms

Classic Sinus Symptoms
1. Sinus "aching" pain or pressure
  1. Location
    1. Frontal: Frontal Headache
    2. Maxillary: Mid-face, dental (upper teeth) pain
    3. Ethmoid: Retro-orbital pain
    4. Sphenoid: Nonspecific pain radiates top of head
  2. Provocative
    1. Pain increases on bending forward
    2. Pain increases in late morning
    3. Pain on mastication
2. Foul Nasal Discharge or postnasal discharge
  1. Purulent yellow or green Nasal Discharge
  2. Discharge color does not indicate Bacterial cause
  3. Discharge for >10 days suggests Bacterial Sinusitis
3. Associated Nasal Symptoms
  1. Decreased Sense of Smell (Hyposmia or Anosmia)
  2. Halitosis
  3. Snoring
  4. Mouth breathing
  5. Nasal or hyponasal speech
4. Generalized symptoms
  1. Fatigue
  2. Fever
Symptoms not correlating with Sinusitis
1. Sore Throat (except with postnasal discharge)
2. Sneezing

Symptoms
Red Flags (consider imaging and ENT referral)

High Fever over 102.2 F (39 C) or peristent fever
Visual complaints (e.g. Diplopia)
Periorbital edema or erythema
Mental status changes
Severe facial or Dental Pain
Infraorbital hypesthesia

Signs

Nasal Mucosa edema and erythema
1. Contrast with Allergic Rhinitis (pale, boggy mucosa)
Nasal exam to view pus discharge from lateral wall
1. Instruments
  1. Nasal speculum (minimal visualization)
  2. Flexible Nasolaryngoscopy
  3. Rigid optical scope (Otolaryngology use)
2. Middle Meatus (hiatus semilunaris)
  1. Drains Maxillary, Frontal, and Anterior Ethmoid
  2. Consider local Topical Decongestant application
3. Superior Meatus (Rarely discharge is seen)
  1. Drains posterior Ethmoid Sinus
Turbinates enlarged
Sinus tenderness to percussion
Sinus Transillumination in darkened room
1. Frontal and Maxillary Sinus

Diagnosis
Findings most suggestive of Bacterial cause

See Sinusitis Prediction Rules
Symptoms persist beyond 10 to 14 days
1. Under 10 days of symptoms, viral Sinusitis predominates
2. By day 10, 40% of Sinusitis resolves spontaneously
3. Only 0.5% of viral URIs develop into Bacterial Sinusitis
  1. Low (1997) CMAJ 156:S1-S14 [PubMed]
Symptoms worsen after 5-7 days ("double sickening")
1. Typical course: Onset, then improvement, then worse again
Purulent Nasal Discharge
Maxillary tooth or facial pain (especially if unilateral)
Unilateral Maxillary Sinus tenderness
References
1. Hickner (2001) Ann Intern Med 134:498-505 [PubMed]
2. Lanza (1997) Otolaryngol Head Neck Surg 117:S1-7 [PubMed]

Diagnosis
Infectious Disease Society of America (IDSA)

Treat as Sinusitis if at least one of 3 criteria present
Onset with severe signs or symptoms
1. High fever (>102.2 F or 39 C) AND
2. Purulent nasal drainage or facial pain for at least 3 to 4 consecutive days at the start of the illness
Persistent Acute Bacterial Rhinosinusitis symptoms >=10 days without clinical improvement
Double Sickening
1. Initial viral Upper Respiratory Infection lasting 5 to 6 days and was improving
2. Then, worsening findings (fever, Headache, increased Nasal Discharge) for at least 3 to 4 days
References
1. Chow (2012) Clin Infect Dis 54(8): e72-112 [PubMed]

Labs

Culture of nasal mucosa
1. Not cost effective or helpful in management
2. Does not correlate with sinus mucosa cultures
Endoscope directed micro-swab culture
1. Swab of hiatus semilunaris
2. Protected from nasal contamination
3. Accuracy: 80-85% compared with antral puncture

Imaging

Indications for Imaging
1. Imaging is not needed in routine cases (esp. Acute Sinusitis)
  1. Does not differentiate viral from Bacterial cause
  2. Empiric therapy for 1-2 courses is appropriate
2. Complicated Sinusitis (esp. Immunocompromised patients)
3. Chronic or recurrent Sinusitis
4. Sinusitis refractory to maximal medical therapy
  1. Example: Amoxicillin course for 10 days followed by Levaquin course for 10-14 days
Sinus XRay (not recommended)
1. Single Waters' View XRay is sufficient
2. Indication (rarely indicated unless CT not available)
  1. Complicated Acute Sinusitis
  2. Suspected Chronic Sinusitis
Sinus CT without contrast (gold standard)
1. Findings
  1. Mucosal thickening >5mm is consistent with sinus infection
  2. Non-contrast CT
    1. Demonstrates fluid and mucosal edema, as well as bony destruction
    2. Fat stranding (increased density) may be present in para-sinus spaces
  3. CT-Contrast CT
    1. Necrotic tissue and fluid does not contrast enhance
    2. Inflamed, thickened mucosa contrast enhances
      1. Mucosa, fluid and soft tissue may be indistinguishable without contrast
    3. Consider IV contrast in complicated cases (e.g. vascular complications, Cavernous Sinus Thrombosis)
2. Indications (cases refractory to maximal medical therapy)
  1. Define Sinus Anatomy prior to Sinus Surgery
  2. Osteomeatal complex Occlusion
  3. Chronic Sinusitis
  4. Recurrent Sinusitis
  5. Allergic Fungal Sinusitis
Sinus MRI
1. No advantage over Sinus CT except for complicated cases (e.g. neoplasm)
  1. More False Positive results
2. Indications
  1. Suspected neoplasm
  2. Orbital or intracranial extension
  3. Fungal Sinusitis
3. Views: T1 Weighted Images with IV gadolinium
  1. Fluid, air, bone are black
  2. Fat is white, but black with fat suppression
  3. Contrast-enhanced mucosa is bright white
  4. Necrotic tissue will not enhance and will appear as black

Complications

Orbital Cellulitis (and Periorbital Cellulitis)
Meningitis
Extradural abscess
Subdural Empyema
1. Subdural Abscess, especially associated with Frontal Sinusitis
Brain Abscess
Pott's Puffy Tumor
1. Osteomyelitis of Frontal Bone or Maxillary Bone
Cavernous Sinus Thrombosis
Fungal Sinusitis
1. Sudden fulminant progression has a high mortality (>50%)
2. Risk of intracranial spread (hematogenous or from adjacent bony destruction)

Management

See Acute Sinusitis Management
Referral Indications
1. See Red Flag Symptoms above

Reference