Acute Sinusitis

Definition And Classification

Inflammation involving mucosal lining paranasal sinuses.
Preferred terminology acute rhinosinusitis secondary concurrent nasal mucosa involvement.
Acute: Symptom duration <30 days.
Subacute: Symptom duration 30-90 days.
Chronic: Symptom duration >90 days continuous inflammation.
Recurrent Acute: >=4 distinct episodes annually demonstrating complete inter-episode resolution.
Acute Bacterial Rhinosinusitis (ABRS): Bacterial superinfection complicating initial viral upper respiratory infection.

Development timeline predicts infection anatomical site based patient age.
Ethmoid And Maxillary: Present, pneumatized at birth. Constitute primary sinusitis sites infants, toddlers.
Sphenoid: Pneumatization occurs ages 3-5 years.
Frontal: Pneumatization begins ages 6-8 years, reaching full development during adolescence. Frontal sinusitis rare children <10 years.

Viral Pathogens (Most Common): Rhinovirus, Influenza, Adenovirus, Parainfluenza, Coronavirus.
Bacterial Pathogens (ABRS): Nontypeable Haemophilus influenzae (~50%), Streptococcus pneumoniae (~30%), Moraxella catarrhalis (~10-20%).
Pathogen Shifts: Routine pneumococcal conjugate vaccination shifted prevalence favoring nontypeable Haemophilus influenzae primary ABRS pathogen.
Severe/Complicated Disease Organisms: Staphylococcus aureus (including methicillin-resistant strains), Streptococcus anginosus group, anaerobes.

Infection strictly follows preceding viral upper respiratory infection.
Viral infection induces mucosal swelling, localized edema.
Edema obstructs narrow (1-3 mm) ostiomeatal complex governing sinus drainage.
Nose blowing forcefully propels colonized nasal secretions sterile sinus cavities.
Impaired mucociliary clearance traps secretions causing profound stasis.
Resulting hypoxic, static environment selectively favors high-titer bacterial overgrowth.

Host Factors: Allergic rhinitis (most frequent risk factor).
Anatomical Defects: Septal deviation, adenoid hypertrophy, nasal polyps, concha bullosa.
Systemic Conditions: Cystic Fibrosis (bilateral polyps), Primary Ciliary Dyskinesia, primary immunodeficiencies.
Environmental/Iatrogenic: Tobacco smoke exposure, prolonged nasogastric/nasotracheal intubation blocking sinus ostia.

Differentiation simple viral infection from ABRS requires strict clinical criteria.
Diagnosis established presence any one three distinct clinical presentations:
- Persistent Symptoms: Nasal discharge (any quality) or daytime cough >10 days lacking clinical improvement.
- Severe Onset: High fever >=39°C (102.2°F) concurrent purulent nasal discharge lasting minimum 3-4 consecutive days initial illness.
- Worsening Course (Double Sickening): Initial viral symptom improvement followed new-onset fever, severe headache, worsening discharge day 6-7.

Clinical Sign/Symptom	Assigned Points
Facial tenderness	3
Severe headache (retro-orbital)	3
Severe abnormal nasal discharge	2
Fever >=38.5°C	2
Cough	2
Mild headache/Minimal discharge/Congestion	1 Each

Clinical Diagnosis: Sufficient uncomplicated acute sinusitis.
Plain Radiographs: Obsolete pediatrics, high false positive/negative rates, not recommended.
Contrast-Enhanced Computed Tomography (CT): Gold standard delineating sinus anatomy. Indications strictly reserved suspected orbital/intracranial complications, surgical planning, severe recalcitrant disease.
Microbiological Diagnosis: Sinus aspirate culture represents gold standard. Routine aspiration impractical, strictly reserved nonresponsive, highly immunocompromised patients.

Viral Upper Respiratory Infection: Clear discharge, symptom duration <10 days.
Allergic Rhinitis: Seasonal variation, profound nasal eosinophilia, transverse nasal crease.
Nasal Foreign Body: Unilateral foul-smelling purulent discharge.

Pediatric sinusitis highly prone anatomical extension secondary extremely thin separating bony walls (lamina papyracea).

Represents most frequent complication, typically originating ethmoiditis.
Stage I (Preseptal Cellulitis): Eyelid edema, erythema. Intact, normal extraocular movement.
Stage II (Orbital Cellulitis): Post-septal inflammation. Proptosis, chemosis, marked ophthalmoplegia.
Stage III (Subperiosteal Abscess): Purulent collection between lamina papyracea, periorbita. Globe displaced laterally/downward.
Stage IV (Orbital Abscess): Purulent collection within intraorbital fat. Imposes severe visual threat.
Stage V (Cavernous Sinus Thrombosis): Bilateral progression, cranial nerve III, IV, VI palsies.

Intracranial Spread: Epidural/Subdural empyema, severe meningitis, brain abscess. Requires emergent broad-spectrum intravenous coverage (Cefotaxime/Ceftriaxone plus Vancomycin, Metronidazole).
Osseous Spread: Pott Puffy Tumor (frontal bone osteomyelitis producing doughy subgaleal forehead swelling).

Watchful Waiting: Observation 3 additional days permissible strictly patients displaying persistent criteria (Criterion 1) lacking severity.
Immediate Pharmacotherapy: Required children exhibiting severe onset or double sickening criteria.

First-Line Therapy: Amoxicillin-clavulanate represents drug choice.
Mild/Moderate Disease: Low-dose Amoxicillin-clavulanate (45 mg/kg/day amoxicillin component divided twice daily).
Severe Disease/High Resistance Risk: High-dose Amoxicillin-clavulanate (80-90 mg/kg/day amoxicillin component divided twice daily).
Penicillin Allergy (Type 1 Hypersensitivity): Levofloxacin (10-20 mg/kg/day).
Penicillin Allergy (Non-Type 1 Hypersensitivity): Cefpodoxime, Cefdinir.
Severe/Hospitalized Cases: Intravenous Ampicillin-sulbactam, Ceftriaxone, Levofloxacin.
Treatment Duration: 10-14 days standard, alternatively 7 days post-complete symptom resolution.

Adjuvant Measures: Normal saline irrigation beneficial clearing viscous secretions. Intranasal steroids offer modest benefit primarily concurrent allergic rhinitis.
Contraindicated Adjuvants: Decongestants, antihistamines strictly NOT recommended, severely thicken secretions impairing clearance.
Surgical Intervention: Functional Endoscopic Sinus Surgery (FESS) establishes drainage/ventilation. Indications include Chandler Stage III+ orbital complications, intracranial extension, failure maximal medical therapy, underlying severe anatomical defects.