External Otitis Diagnosis and Coding

Definition and Clinical Presentation

External otitis is defined as an infection of the cutis and subcutis of the external auditory canal (EAC), with variable involvement of the pinna, and is characterized by symptoms such as otalgia, tenderness, fever, and ear discharge, affecting adults more commonly, with a lifetime incidence of approximately 10% 1
The most common causative organisms are Pseudomonas aeruginosa and Staphylococcus aureus, which account for 98% of cases in North America, and are bacterial in nature 1, 2

The American College of Radiology recommends using the ICD-10 code H60.9 for unspecified otitis externa, with more specific codes available based on the type and location, such as H60.0 for abscess of external ear, H60.2 for malignant otitis externa, H60.3 for other infective otitis externa, H60.4 for cholesteatoma of external ear, and H60.5 for acute otitis externa, non-infective 1
The ICD-10 code H60.2 is used for necrotizing (malignant) otitis externa, a fulminant infection with extension beyond the EAC, particularly in patients with diabetes or immunosuppression, with a high level of evidence supporting its use 1, 3

Proper coding is important for accurate documentation of the condition, appropriate reimbursement for treatment, tracking epidemiological data, and ensuring continuity of care, with the American College of Radiology emphasizing the need for specificity in coding 2, 3
The strength of evidence for proper coding is high, with multiple studies supporting its importance in ensuring accurate documentation and reimbursement 3

Fungal otitis externa, which is less common and generally caused by Aspergillus or Candida species, requires specific coding, such as H60.391 for right ear, H60.392 for left ear, and H60.393 for bilateral, with the American College of Radiology recommending its use 1, 3
Swimmer's ear, which is common in swimmers due to conversion of normal acidic environment to alkaline, requires specific coding, such as H60.331 for right ear, H60.332 for left ear, and H60.333 for bilateral, with a moderate level of evidence supporting its use 1

The American College of Radiology warns against confusing external otitis (H60 codes) with otitis media (H65-H67 codes), which affects the middle ear, with a high level of evidence supporting the importance of accurate coding 2
Ensuring specificity in coding when the type of external otitis is known (acute, chronic, fungal, etc.) is crucial, with the American College of Radiology recommending its use, and a high level of evidence supporting its importance 3

The American College of Radiology recommends that diagnosis is largely clinical, and uncomplicated cases can generally be treated with topical antibiotics and analgesics, with a high level of evidence supporting its use 1, 2
Topical therapy delivers antimicrobial concentrations 100-1000 times higher than systemic therapy, with a moderate level of evidence supporting its use, and the American College of Radiology recommending its use 2
Oral antibiotics should be reserved for cases with extension beyond the ear canal or in immunocompromised patients, with a high level of evidence supporting its use, and the American College of Radiology recommending its use 3