HSC Section 8_April 2017

Reprinted by permission of Otolaryngol Head Neck Surg. 2014; 15(1):112-116.

Original Research—Otology and Neurotology

Otolaryngology– Head and Neck Surgery 2014, Vol. 151(1) 112–116 American Academy of Otolaryngology—Head and Neck

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

Surgery Foundation 2014 Reprints and permission:

sagepub.com/journalsPermissions.nav DOI: 10.1177/0194599814528301 http://otojournal.org

Candace E. Hobson, MD 1 , Jennifer D. Moy, MD 1 , Karin E. Byers, MD 2 , Yael Raz, MD 1 , Barry E. Hirsch, MD 1 , and Andrew A. McCall, MD 1

Received September 3, 2013; revised January 16, 2014; accepted February 26, 2014.

No sponsorships or competing interests have been disclosed for this article.

Abstract Objective. Malignant otitis externa (MOE) is an invasive infection of the temporal bone that is classically caused by Pseudomonas aeruginosa . Increasingly, however, nonpseudomonal cases are being reported. The goal of this study was to evaluate and com- pare the clinical presentation and outcomes of cases of MOE caused by Pseudomonas versus non- Pseudomonas organisms.

Introduction Malignant otitis externa (MOE) is a potentially life-threatening osteomyelitis of the temporal bone that can extend to involve the surrounding soft tissues, cranial nerves, and adjacent skull base. Elderly, diabetic, or immunocompromised patients are most frequently afflicted. In 1959, Meltzer and Kelemen 1 first described this infection in a case report of a patient with dia- betes with fatal temporal bone osteomyelitis that originated from otitis externa. Cultures from their patient’s ear grew Bacillus pyocyanea , which is now known as Pseudomonas aeruginosa . In 1968, Chandler 2 coined the term ‘‘malig- nant otitis externa’’ to describe this morbid pseudomonal infection. Since then, the presence of Pseudomonas in affected ears has been thought to be one of the hallmark features of this disease. 3 It was not until 1982 that the first case of nonpseudomonal MOE was reported. In that report, Bayardelle et al 4 described a case of MOE due to oxacillin-sensitive Staphylococcus aureus . Since then, there have been multiple reports of S aureus as the sole offending organism in MOE. 5,6 There have been few reports of methicillin-resistant S aureus (MRSA) as the causative pathogen in MOE 7,8 ; however, the overall inci- dence of MRSA skin and soft tissue infections has been rising steadily. 9 Additionally, although earlier reports revealed P aer- uginosa as the causative organism in most cases of MOE, 1 Department of Otolaryngology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA 2 Department of Medicine, Division of Infectious Diseases, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA This article was presented as a poster at the 2013 AAO-HNSF Annual Meeting & OTO EXPO; September 29 to October 3, 2013; Vancouver, British Columbia, Canada. Corresponding Author: Andrew A. McCall, University of Pittsburgh, Department of Otolaryngology–Head and Neck Surgery, 203 Lothrop Street, Suite 500,

Study Design. Retrospective case series with chart review.

Setting. Tertiary care institution.

Subjects and Methods. Adult patients with diagnoses of MOE between 1995 and 2012 were identified. Charts were reviewed for history, clinical presentation, laboratory data, treatment, and outcomes. Results. Twenty patients diagnosed with and treated for MOE at the University of Pittsburgh Medical Center between 1995 and 2012 were identified. Nine patients (45%) had cultures that grew P aeruginosa . Three patients (15%) had cultures that grew methicillin-resistant Staphylococcus aureus (MRSA). Signs and symptoms at presentation were similar across groups. However, all of the patients with Pseudomonas had diabetes, compared with 33% of MRSA-infected patients ( P = .046) and 55% of all non- Pseudomonas -infected patients ( P = .04). Patients infected with MRSA were treated for an average total of 4.7 more weeks of antibiotic therapy than Pseudomonas - infected patients ( P = .10). Overall, patients with non- Pseudomonas infections were treated for a total of 2.4 more weeks than Pseudomonas -infected patients ( P = .25). Conclusions. A high index of suspicion for nonpseudomonal organisms should be maintained in patients with signs and symptoms of MOE, especially in those without diabetes. MRSA is an increasingly implicated organism in MOE. Keywords malignant otitis externa, necrotizing otitis externa, methicillin- resistant Staphylococcus aureus , MRSA, Pseudomonas aerugi- nosa , otitis externa

Pittsburgh, PA 15213, USA Email: mccallaa@upmc.edu

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