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Malignant Otitis Externa: Evolving Pathogens and Implications for Diagnosis and Treatment

Candace E Hobson1, Jennifer D Moy1, Karin E Byers2

  • 1Department of Otolaryngology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.

Otolaryngology--Head and Neck Surgery : Official Journal of American Academy of Otolaryngology-Head and Neck Surgery
|March 29, 2014
PubMed
Abstract

Insights

Malignant otitis externa (MOE) can be caused by organisms other than Pseudomonas aeruginosa, including methicillin-resistant Staphylococcus aureus (MRSA). Non-Pseudomonas infections may present differently, particularly in patients without diabetes.

Area of Science:

  • Infectious Diseases
  • Otolaryngology
  • Bacterial Infections

Background:

  • Malignant otitis externa (MOE) is a severe invasive infection of the temporal bone.
  • Pseudomonas aeruginosa is the classic causative agent, but non-pseudomonal infections are increasingly recognized.

Purpose of the Study:

  • To compare the clinical presentation and outcomes of MOE caused by Pseudomonas versus non-Pseudomonas organisms.
  • To evaluate the role of methicillin-resistant Staphylococcus aureus (MRSA) in MOE.

Main Methods:

  • Retrospective case series with chart review of adult patients diagnosed with MOE between 1995 and 2012.
  • Analysis of clinical presentation, laboratory data, treatment, and outcomes for Pseudomonas and non-Pseudomonas infections.

Main Results:

  • Nine of twenty MOE patients (45%) had Pseudomonas infections; three (15%) had MRSA infections.
  • Clinical presentation was similar, but Pseudomonas infections were more common in diabetic patients.
  • Non-Pseudomonas infections, including MRSA, required longer antibiotic treatment durations.

Conclusions:

  • Maintain a high suspicion for non-Pseudomonas organisms in MOE, especially in non-diabetic patients.
  • MRSA is an emerging pathogen in malignant otitis externa.
Keywords:
MRSAPseudomonas aeruginosamalignant otitis externamethicillin- resistant Staphylococcus aureusnecrotizing otitis externaotitis externa

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