Last reviewed: 12 May 2021
Last updated: 04 Aug 2020



History and exam

Key diagnostic factors

  • symptoms <10 days (acute viral sinusitis)
  • symptoms >10 days but <4 weeks (acute bacterial sinusitis)
  • symptoms that worsen after an initial improvement (acute bacterial sinusitis)
  • purulent nasal discharge
  • nasal obstruction
  • facial pain/pressure
  • severe symptoms at onset (acute bacterial sinusitis)
  • dental pain

Other diagnostic factors

  • cough
  • myalgia
  • sore throat
  • hyposmia
  • edematous turbinate
  • fever

Risk factors

  • viral upper respiratory tract infection
  • allergic rhinitis
  • GERD

Diagnostic investigations

Investigations to consider

  • nasal endoscopy
  • sinus culture
  • CT sinuses (noncontrast)
  • x-ray sinuses
  • MRI
  • lateral neck x-ray

Treatment algorithm


Gordon H. Sun

Chief Medical Information Officer

Chief of Otolaryngology

Rancho Los Amigos National Rehabilitation Center




GS is a consultant with Partnership for Health Analytic Research, LLC and Gerson Lehrman Group, Inc for medical research and expert opinion work. GS is a contractor with Medscape for WebMD for writing healthcare-related articles.

Dr Gordon H. Sun would like to gratefully acknowledge Dr Melissa A. Pynnonen and Dr Joseph K. Han, previous contributors to this topic.


MAP and JKH declare that they have no competing interests.

Peer reviewersVIEW ALL

Instructor of Otology and Laryngology

Harvard Medical School

Massachusetts Eye and Ear Infirmary

Department of Otolaryngology - Head and Neck Surgery




BSB is a co-founder and equity shareholder in Luxxeal, Inc.

Assistant Professor/Consultant

Academic Medical Center


The Netherlands


CG declares that he has no competing interests.

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