Rhinosinusitis Clinical Overview
I. The "On-Call" Snapshot
Clinical Significance in Malaysia: This is one of the most common reasons patients see a GP, and it frequently clogs up our outpatient clinics and the ED, especially when it's mistaken for a simple cold that won't go away. Your job is to differentiate viral from bacterial and know when not to give antibiotics.
High-Yield Definition: Per the Malaysian CPG on Rhinosinusitis (2016), it is an inflammation of the nose and paranasal sinuses characterised by two or more symptoms, one of which should be either nasal blockage/obstruction/congestion or nasal discharge (anterior/posterior drip). The other symptoms can be facial pain/pressure or a reduction/loss of smell.
Clinical One-Liner: Basically, it’s a blocked and inflamed sinus, usually from a cold. Our job is to figure out if bacteria have taken over the mess.
II. Etiology & Risk Factors
Etiology: The vast majority (>98%) of cases are viral (Rhinovirus, Influenza, Parainfluenza virus). A secondary bacterial infection is uncommon. The main culprits when it becomes bacterial are Streptococcus pneumoniae and Haemophilus influenzae. Less commonly, Moraxella catarrhalis, especially in children.
Risk Factors:
Modifiable: Smoking (active and passive), uncontrolled allergic rhinitis.
Non-Modifiable: Anatomical defects (e.g., deviated nasal septum, nasal polyps), asthma, immunodeficiency.
III. Quick Pathophysiology
It's straightforward. A preceding event, usually a viral URI or an allergic reaction, causes the sinonasal mucosa to swell up. This inflammation obstructs the sinus ostia—the small drainage pathways. Mucus gets trapped, stagnates, and the cilia can't clear it. This creates a perfect, low-oxygen environment for bacteria to thrive, leading to acute bacterial rhinosinusitis (ABRS).
IV. Clinical Assessment
Red Flags & Immediate Actions: If you see any of these, you call your senior and/or the ENT registrar immediately. This is an urgent referral (within 24 hours).
Periorbital oedema, erythema, displaced globe, diplopia, reduced visual acuity: Suspect orbital cellulitis/abscess. -> Action: Escalate to senior, prep for CT scan.
Severe, unilateral frontal headache: Concerning for frontal sinus involvement. -> Action: Escalate.
Forehead swelling (Pott's puffy tumour): Sign of subperiosteal abscess. -> Action: Escalate immediately.
Signs of meningitis (neck stiffness, altered consciousness): Suspect intracranial extension. -> Action: Escalate, start sepsis workup.
History: The key is the timeline. A viral URI should start improving by day 5. ABRS is suggested by three key patterns:
Persistent Symptoms: Symptoms lasting >10 days without any improvement.
"Double Worsening": Initial improvement from a viral URI, followed by a sudden worsening of symptoms after day 5.
Severe Onset: High fever (>38°C) and purulent nasal discharge or facial pain for at least 3-4 consecutive days from the beginning.
Common (>50%): Nasal blockage, purulent (yellow/green) nasal discharge, facial pain or pressure (worse on bending forward), post-nasal drip.
Less Common (10-50%): Reduced sense of smell (hyposmia), fever, cough (especially worse at night), headache, dental pain (maxillary).
Pertinent Negatives: Ask about visual changes, severe headache, or neck stiffness to rule out complications.
Physical Examination:
General: Check for fever, signs of toxicity.
Face: Palpate for tenderness over the frontal and maxillary sinuses. Check for any swelling or erythema, especially around the eyes.
Nose: Perform an anterior rhinoscopy. Look for mucosal oedema, erythema, and purulent discharge, especially from the middle meatus.
Throat: Look for posterior pharyngeal wall cobblestoning or purulent discharge from post-nasal drip.
Clinical Pearl: Don't be fooled by the colour of the mucus alone. Purulent discharge can be seen in viral rhinosinusitis. The timing and overall clinical picture are more important than the colour of their sputum.
V. Diagnostic Workflow
Differential Diagnosis:
Common Cold (Viral URI):
Points For: Symptoms less than 10 days, improving after day 5.
Points Against: "Double worsening" course, high fever after the first few days.
How to Differentiate: Primarily based on the clinical timeline.
Allergic Rhinitis:
Points For: Itchy nose, sneezing, clear watery rhinorrhea, seasonal pattern.
Points Against: Fever, purulent discharge, significant facial pain.
How to Differentiate: Clinical history and presence of other allergic features (e.g., allergic shiners). An antihistamine trial might help.
Dental Abscess:
Points For: Unilateral maxillary pain, recent dental procedure, pain localised to a tooth.
Points Against: Bilateral symptoms, significant nasal congestion without preceding dental issues.
How to Differentiate: Dental examination and orthopantomogram (OPG).
Investigations Plan: For uncomplicated ABRS in primary care, this is a clinical diagnosis. No imaging needed.
Bedside / Initial (First 15 Mins): Not usually required unless the patient looks toxic (sepsis workup) or you suspect red flags.
First-Line Labs & Imaging:
DO NOT do nasal swabs in primary care. They are poor predictors of the actual pathogen.
Plain sinus X-rays are not recommended anymore. They are not sensitive or specific.
Confirmatory / Gold Standard:
CT scan of the sinuses is the gold standard but is only indicated if you suspect complications, the diagnosis is unclear, or the patient fails to respond to treatment and is being considered for surgery by ENT.
VI. Staging & Severity Assessment
We classify acute rhinosinusitis based on duration and symptoms to guide management.
Acute Viral Rhinosinusitis (Common Cold): Symptoms <10 days, not worsening.
Post-Viral Rhinosinusitis: Symptoms worsen after day 5 OR persist for >10 days.
Acute Bacterial Rhinosinusitis (ABRS): Requires at least three of the following:
Discoloured discharge (unilateral predominance) & purulent secretion in the nasal cavity.
Severe local pain (unilateral predominance).
Fever (>38°C).
Elevated ESR/CRP (not routinely done, but a clue).
"Double worsening" sign.
Impact on Management: Viral and most post-viral cases need only symptomatic treatment. Only true ABRS should be considered for antibiotics.
VII. Management Plan
Immediate Stabilisation (The ABCDE Plan): Only for patients with red flags or signs of sepsis. Secure IV access, give fluids if hypotensive, start oxygen if hypoxic, and get senior help fast.
Definitive Treatment (The Ward Round Plan):
For ALL patients (Viral, Post-Viral, and Bacterial):
Analgesia: Paracetamol or NSAIDs for facial pain and fever.
Nasal Saline Irrigation: High-volume, low-pressure saline rinse (e.g., using a squeeze bottle or neti pot). This mechanically clears mucus and inflammatory mediators. Crucial.
Intranasal Corticosteroids (INCS): Mometasone or fluticasone spray, one or two sprays per nostril daily for at least 14-21 days. It reduces mucosal inflammation. This is a cornerstone of therapy.
If you diagnose ABRS (and only ABRS):
You can offer either watchful waiting for 48-72 hours if symptoms are mild, or start antibiotics.
First-Line Antibiotics:
Amoxicillin 500mg TDS for 5-7 days.
Amoxicillin-Clavulanate (Augmentin) 625mg TDS for 5-7 days. (Use this if the patient is at higher risk for resistance, e.g., recent antibiotic use).
Second-Line (Penicillin Allergy):
Doxycycline or a respiratory fluoroquinolone (Levofloxacin). Macrolides (e.g., Azithromycin) are generally not recommended due to high rates of S. pneumoniae resistance.
Long-Term & Discharge Plan:
Advise to complete the course of INCS.
Educate on smoking cessation and managing allergic rhinitis.
Provide strict return advice for any red flag symptoms.
VIII. Complications
These are rare but are the reason for our red flags.
Orbital (most common): Preseptal cellulitis, orbital cellulitis, subperiosteal abscess. Management: Urgent ENT and Ophthalmology review, IV antibiotics, and likely a CT scan.
Intracranial: Meningitis, brain abscess, cavernous sinus thrombosis. Management: Neurological emergency, requires immediate multidisciplinary input.
Bony: Osteomyelitis of the frontal bone (Pott's puffy tumour). Management: Surgical emergency.
IX. Prognosis
Excellent. Most viral sinusitis resolves within 7-10 days. Even uncomplicated ABRS has a high rate of spontaneous resolution.
Prognostic Factors for complicated disease: Immunocompromised status (uncontrolled DM, HIV), frontal or sphenoid sinus involvement, anatomical abnormalities.
X. How to Present to Your Senior
"Dr, for review please. This is [patient name, age, bed] with a 12-day history of nasal congestion and purulent rhinorrhea that worsened after initial improvement. On examination, there is right maxillary tenderness and pus in the middle meatus. My main differential is acute bacterial rhinosinusitis. I have advised analgesia and intranasal steroids. I would like to ask if we should start a course of Amoxicillin as per CPG."
XI. Summary & Further Reading
Top 3 Takeaways:
Diagnosis is clinical, based on symptom duration and pattern (persistent >10 days or "double worsening"). Don't order X-rays.
Management for everyone includes intranasal corticosteroids and saline irrigation. This is more important than antibiotics.
Reserve antibiotics for clear cases of ABRS. Most patients do not need them. Know the red flags for urgent referral.
Key Resources:
Malaysian CPG: Management of Rhinosinusitis in Adolescents and Adults (2016). Available on the MOH website.
UpToDate: Search for "Acute rhinosinusitis in adults".
National Antimicrobial Guideline (NAG): Check the latest version for local antibiotic recommendations.
