Sinusitis

Overview – Sinusitis (Acute and Chronic)

Sinusitis refers to inflammation of the paranasal sinuses and is classified by duration as acute (<4 weeks) or chronic (>3 months). Acute sinusitis is typically viral in origin and presents with facial pain, congestion, and mucopurulent discharge. Chronic sinusitis involves persistent symptoms and may be driven by inflammation, allergy, or unresolved infection. Early recognition and appropriate treatment — medical or surgical — are key to preventing complications and improving quality of life.

Acute Suppurative Sinusitis

Definition

Acute infection and inflammation of the paranasal sinuses lasting less than 4 weeks.

Aetiology

Viral (most common)

• Rhinovirus
• Influenza
• Parainfluenza

Bacterial

• Streptococcus pneumoniae (~35%)
• Haemophilus influenzae (~35%)
• Moraxella catarrhalis
• Anaerobes (especially with dental origin)

Clinical Features

Symptoms

• Facial pain or pressure (especially over the affected sinus)
• Nasal congestion
• Purulent nasal discharge
• Fever

Bacterial Features

• Symptoms lasting >10 days
• Mucopurulent discharge

Investigations

• Usually a clinical diagnosis
• Transillumination of sinuses may show opacity
• Optional:
  • Skull X-ray: sinus opacification or fluid levels

Management

• Paracetamol for fever and pain
• Decongestants (phenylephrine or pseudoephedrine)
• Intranasal corticosteroids (e.g. Mometasone – Nasonex)
• +/- Antibiotics (if bacterial suspected):
  • Amoxicillin + Clavulanate (Augmentin)
  • Roxithromycin (Rulide)
• Supportive care: hydration, steam inhalation

Chronic Sinusitis

Definition

Sinus inflammation lasting >3 months, often leading to irreversible epithelial changes and mucosal thickening.

Aetiology

• Inadequately treated acute sinusitis
• Untreated allergic rhinitis
• Chronic inflammatory conditions (e.g. Wegener’s granulomatosis)

Clinical Features

• Facial pain or pressure (often milder than in acute)
• Chronic nasal congestion
• Halitosis
• Postnasal drip
• Fatigue

Investigations

• Clinical diagnosis
• Head CT (for surgical planning or to assess extent)

Management

• Antibiotics for 3–6 weeks:
  • Amoxicillin + Clavulanate (Augmentin)
  • Roxithromycin (Rulide)
• Intranasal corticosteroids (Mometasone)
• Decongestants (Phenylephrine / Pseudoephedrine)
• Surgical options if medical therapy fails:
  • Functional endoscopic sinus surgery (FESS)

Differential Diagnosis

• Allergic rhinitis
• Nasal polyps
• Upper respiratory tract infection
• Dental abscess
• Migraine or tension headaches

Summary – Sinusitis (Acute and Chronic)

Sinusitis is a common upper respiratory tract condition classified by duration into acute and chronic forms. While viral causes predominate in acute cases, chronic sinusitis may involve persistent inflammation or structural issues. Diagnosis is primarily clinical, and treatment ranges from supportive care and antibiotics to surgery in refractory cases. For broader context, visit our Respiratory Overview page.