Rhinosinusitis

Overview

Inflammation of nasal mucosa + paranasal sinuses - almost never occurs in isolation
Vast majority of acute cases are viral (rhinovirus most common); bacterial superinfection complicates ~0.5-2% of viral URTIs
Common bacterial pathogens: *Streptococcus pneumoniae*, *Haemophilus influenzae*, *Moraxella catarrhalis*

Classification

Type
Duration
Acute
<12 weeks, resolves completely
Chronic
≥12 weeks, symptoms persist

Presentation

Diagnosis requires: nasal blockage or discharge PLUS at least one of: facial pain/pressure OR reduced/loss of smell
Nasal blockage/congestion - mucosal oedema
Purulent nasal discharge - yellow/green; does NOT reliably indicate bacterial cause
Facial pain/pressure - worse on bending forward; maxillary = cheek pain; frontal = forehead pain; ethmoid = periorbital/nasal bridge pain
Hyposmia/anosmia - olfactory cleft oedema
Upper tooth pain - classic feature of maxillary sinusitis (molar roots abut sinus floor)
Features suggesting bacterial superinfection:
Double-sickening - worsening after initial improvement
Unilateral facial pain or tenderness
Purulent discharge with fever persisting >10 days
High fever (>38°C) or fever persisting beyond 3-4 days

Investigations

Rhinosinusitis is a clinical diagnosis - investigations not required in straightforward acute cases
First-line (if needed): clinical assessment + anterior rhinoscopy; bloods (FBC, CRP) if bacterial superinfection or sepsis suspected

🏆 Gold standard

CT sinuses (coronal) - for chronic rhinosinusitis, surgical planning, or suspected complications; plain X-rays not recommended

🥈 Second-line

MRI if intracranial/orbital complications suspected (superior soft tissue detail); allergy testing (skin prick or specific IgE) in chronic/recurrent disease

Management

Most acute rhinosinusitis is self-limiting - resolves within 2-3 weeks without antibiotics
No antibiotic or delayed antibiotic strategy for most patients (antibiotics reduce symptom duration by ~half a day only)
First-line (all patients):
Saline nasal irrigation - high-volume, twice daily
Analgesia - paracetamol or ibuprofen (ibuprofen has additional anti-inflammatory benefit)
Intranasal corticosteroid - mometasone or fluticasone up to 3 months; especially useful with co-existing allergic rhinitis or chronic rhinosinusitis
Antibiotics - when to prescribe: severe symptoms, bacterial superinfection features (double-sickening, symptoms >10 days without improvement, high fever), immunocompromised, or significant co-morbidities
First-line antibiotic: phenoxymethylpenicillin 500 mg four times daily for 5-7 days
Second-line antibiotic: co-amoxiclav - if no improvement with penicillin V after 2-3 days, or more severely unwell
Penicillin allergy: doxycycline - first-line alternative
Topical decongestant (second-line): xylometazoline or oxymetazoline - limit to 5-7 days (risk of rhinitis medicamentosa with prolonged use)
Chronic rhinosinusitis: intranasal corticosteroids (up to 3 months), treat allergic rhinitis, refer ENT if persistent or polyps present; FESS is definitive surgical option - improves symptoms in ~80% of selected patients
💡
A delayed prescription strategy (collect only if not improved after 7-10 days, or if worsening) reduces antibiotic use without compromising outcomes - consistent with NICE antimicrobial stewardship principles.

Complications

Orbital complications (most common) - periorbital/preseptal cellulitis → subperiosteal abscess → orbital abscess → cavernous sinus thrombosis (Chandler's staging)
Cavernous sinus thrombosis - proptosis, chemosis, ophthalmoplegia, high fever, severe headache; bilateral involvement distinguishes from orbital cellulitis; neurosurgical emergency
Meningitis - neck stiffness, photophobia, altered consciousness
Intracranial abscess - frontal sinusitis classically causes frontal lobe abscess; altered behaviour, focal neurology, reduced GCS
Pott's puffy tumour - subperiosteal abscess of frontal bone; fluctuant forehead swelling with osteomyelitis
🚨
Red flags requiring same-day emergency assessment: periorbital swelling/erythema, proptosis or restricted eye movements, visual changes, severe/worsening headache, neck stiffness or photophobia, altered consciousness or focal neurology, frontal swelling.