Acute otitis externa (AOE), known as “swimmer’s ear,” is an infection and inflammation of the external auditory canal, primarily caused by bacteria.1 Patients may present with ear pain, discharge, pruritus, hearing loss, jaw pain, or fever. Infections, including ear infections, pose significant risks for people with diabetes (PWD), often leading to poorer outcomes compared to the general population.2
Chronic hyperglycemia in PWD impairs immune function, reducing the body’s ability to fight infections.3 Additionally, microvascular damage and neuropathy compromise blood flow and sensory function in the ear, potentially diminishing pain perception and allowing infections to advance unchecked.
Pseudomonas aeruginosa is commonly associated with AOE, and in PWD, it can result in significant inflammation and necrosis.4 Necrotizing otitis externa (NOE) should be considered if PWD present with AOE. NOE is a severe infection that extends from the auditory canal to nearby soft tissue and the skull base, potentially leading to temporal bone osteomyelitis. Symptoms may include facial nerve paralysis, sensorineural hearing loss, and vertigo.5 Although clinical diagnosis is key, CT or MRI can provide supportive confirmation.
Topical antibiotics, with or without steroids, are the first-line treatment for uncomplicated AOE. Systemic antibiotics are typically not recommended initially but should be considered for PWD due to immunosuppression and increased NOE risk. Systemic antibiotics are particularly warranted if there is evidence of systemic involvement, severe local inflammation, or failure of topical therapy. Management of NOE may require an otolaryngologist or infectious disease specialist.
Effective hyperglycemia management is essential for PWD with AOE because high blood glucose can impair immune responses.3,6 Strategies include insulin, oral hypoglycemic agents, and newer injectable therapies such as GLP-1 receptor agonists and GLP-1/GIP dual agonists, which have shown benefits for glycemic management and cardiovascular risk reduction. Continuous glucose monitoring technology should also be incorporated to optimize blood glucose management, providing real-time feedback and enhancing self-management.7 Healthy eating and active living are integral components of diabetes management and infection prevention because they contribute to improved glycemic management and overall health outcomes.8
Defining glycemic targets is critical, with an A1C <7% being associated with a reduced risk of microvascular complications, including those affecting the ear.9 It is important to note that these recommendations apply primarily to adults with type 1 or type 2 diabetes; however, pediatric considerations would require further tailoring of treatment goals and strategies. A multidisciplinary approach addressing infection control, metabolic health, and lifestyle modifications is crucial for optimal outcomes in PWD with AOE.10 This approach not only supports infection resolution but also helps prevent future complications and recurrence.
Brian Burroughs, MSPAS, PA-C, BC-ADM, CDCES, works in family medicine at the Mayo Clinic Health System in Red Wing, Minnesota.
Rosenfeld RM, Schwartz SR, Cannon CR, et al. Clinical practice guideline: acute otitis externa. Otolaryngol Head Neck Surg. 2014;150(1 suppl):S1-S24. doi:10.1177/0194599813517083
Berbudi A, Rahmadika N, Tjahjadi AI, Ruslami R. Type 2 diabetes and its impact on the immune system. Curr Diabetes Rev. 2020;16(5):442-449. doi:10.2174/1573399815666191024085838
Tsilivigkos C, Avramidis K, Ferekidis E, Doupis J. Malignant external otitis: what the diabetes specialist should know-a narrative review. Diabetes Ther. 2023;14(4):629-638. doi:10.1007/s13300-023-01390-9
Critchley JA, Carey IM, Harris T, DeWilde S, Hosking FJ, Cook DG. Glycemic control and risk of infections among people with type 1 or type 2 diabetes in a large primary care cohort study. Diabetes Care. 2018;41(10):2127-2135. doi:10.2337/dc18-0287
Flint PW, Francis HW, Haughey BH, et al. Cummings Otolaryngology: Head and Neck Surgery. 7th ed. Elsevier; 2021.
Mani N, Sudhoff H. Malignant otitis externa: challenges and strategies. Infect Drug Resist. 2020;13:3657-3671. doi:10.2147/IDR.S278668
Battelino T, Danne T, Bergenstal RM, et al. Clinical targets for continuous glucose monitoring data interpretation: recommendations from the international consensus on time in range. Diabetes Care. 2019;42(8):1593-1603. doi:10.2337/dci19-0028
Srivastava AK, Thomas AR, Chandra M. Role of lifestyle management in prevention of type 2 diabetes—a review of evidence. Diabetes Metab Syndr. 2023;17(1):102573. doi:10.1016/j.dsx.2022.102573
Stratton IM, Adler AI, Neil HA, et al. Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): prospective observational study. BMJ. 2000;321(7258):405-412. doi:10.1136/bmj.321.7258.405
Fathi R, Estrada E, Tobin E. Comprehensive management of diabetes and infection risks. Prim Care Diabetes. 2022;16(3):271-278. doi:10.1016/j.pcd.2021.12.007
