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Last reviewed: 18 Mar 2025
Last updated: 26 Apr 2022

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • malodorous breath
  • consumption of onions, garlic, or spiced food
  • evidence of dental and/or periodontal disease
  • evidence of disease of the oral mucosa
  • evidence of nasopharyngeal disease

Other diagnostic factors

  • evidence of upper respiratory tract or gastrointestinal disease
  • evidence of upper respiratory tract and gastrointestinal malignancy
  • evidence of endocrine, metabolic, hepatic, or renal disease

Risk factors

  • oral disease
  • respiratory disease
  • gastrointestinal disease
  • hepatic disease
  • renal disease
  • endocrine disease or hormonal changes
  • metabolic disease

Diagnostic investigations

Investigations to consider

  • sulfide monitor
  • gas chromatography
  • benzol-arginine-naphthylamide (BANA) test
  • dark-field microscopy
  • polymerase chain reaction of oral bacteria
  • selected ion flow tube mass spectroscopy

Treatment algorithm

Contributors

Authors

Stephen R. Porter, BSc, PhD, MD, FDSRCS, FDSRCSEd, FHEA
Stephen R. Porter

Director and Professor of Oral Medicine

UCL Eastman Dental Institute

London

UK

Disclosures

SRP declares that he has no competing interests.

Stefano Fedele, DDS, PhD
Stefano Fedele

Professor of Oral Medicine

UCL Eastman Dental Institute

London

UK

Disclosures

SF declares that he has no competing interests.

Peer reviewers

Giuseppina Campisi, DDS, PhD

Professor of Oral Medicine

Department of Oral Sciences

University of Palermo

Palermo

Italy

Disclosures

GC declares that she has no competing interests.

Ronald S. Brown, MD, DDS

Professor

Howard University College of Dentistry

Washington

DC

Disclosures

RSB declares that he has no competing interests.

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