What are the red flags for acute sinusitis?

Red Flags Requiring Urgent Assessment

A comprehensive review of sinusitis complications identifies 10 alarming symptoms/signs that mandate urgent hospital referral:

1. Swelling or redness in the orbital area
2. Globe malposition, protrusion, or strabismus
3. Diplopia
4. Ophthalmoplegia
5. Reduced visual acuity
6. Severe headache
7. Swelling of the forehead
8. Signs or symptoms of sepsis
9. Signs or symptoms of meningitis
10. Signs or symptoms of neurological impairment

Orbital complications

The orbit is the most common structure involved in complicated sinusitis, usually from ethmoid sinusitis. Periorbital oedema, double vision, ophthalmoplegia, or visual compromise should prompt immediate referral and hospitalisation. Emergent CT with contrast is recommended in the presence of visual symptoms such as diplopia, decreased visual acuity, or disconjugate gaze.

Intracranial complications

These include meningitis, epidural or subdural empyema, and brain abscess. Key warning features are severe headache, neck stiffness, confusion, somnolence, and focal neurological signs. Neurological and neurosurgical consultation is advised.

Systemic red flags

High fever (≥38.3 °C), particularly in combination with purulent nasal discharge persisting ≥3-4 days, suggests severe bacterial sinusitis requiring earlier antibiotic therapy. Any signs of sepsis warrant urgent management.

Clinical deterioration patterns

• No improvement after 10 days or worsening within 10 days after initial improvement ("double worsening") suggests acute bacterial rhinosinusitis
• Failure to respond to appropriate antibiotic therapy should prompt reassessment and consideration of specialist referral