ENT

Sinusitis: From Diagnosis to Treatment

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 (e.g., periorbital cellulitis, 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

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

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 e.g., 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)
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