Symptoms of Malignant Otitis Externa
Malignant otitis externa (MOE) presents with severe, unrelenting deep otalgia (ear pain) that is often disproportionate to examination findings, persistent purulent otorrhea (ear discharge), and granulation tissue typically seen on the floor of the ear canal and at the bony-cartilaginous junction. 1, 2
Primary Symptoms
- Severe, persistent otalgia (pain out of proportion to exam findings) 2, 3
- Persistent purulent otorrhea (ear discharge) 2, 4
- Deep-seated ear pain that doesn't respond to standard treatment 5
- Granulation tissue in the external auditory canal, particularly at the floor and bony-cartilaginous junction 1, 4
Advanced Symptoms and Complications
- Cranial nerve involvement, with facial nerve (VII) paralysis being the most common 2, 4
- Headache, vertigo, and meningismus (neck stiffness) in cases with intracranial spread 1
- Neurological deficits as the infection progresses 2
- Regional lymphadenitis 1
- Fever, especially in advanced cases 4
Risk Factors and Demographics
- Primarily affects elderly patients with diabetes mellitus 4, 3
- Other risk factors include immunosuppression and advanced age 2
- Chronic renal failure patients on dialysis are at increased risk 4
Diagnostic Indicators
- Elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) 6, 3
- Pseudomonas aeruginosa is the most common causative organism (though MRSA and fungi can also cause it) 2, 4
- Non-responsiveness to standard otitis externa treatment is a key clinical indicator 2
- Imaging findings (CT or MRI) showing bony destruction of the temporal bone or skull base 2, 6
Differentiating from Acute Otitis Externa
- Malignant otitis externa shows more severe, persistent symptoms compared to acute otitis externa 1, 2
- Presence of granulation tissue is characteristic of malignant otitis externa but not typical in acute otitis externa 1
- Malignant otitis externa involves bone invasion and potential intracranial spread, unlike acute otitis externa 1, 2
- Acute otitis externa typically responds to topical treatment, while malignant otitis externa requires systemic antibiotics and possibly surgical intervention 7, 4
Clinical Course
- Progressive infection that extends from the external auditory canal to the temporal bone and potentially to intracranial structures 2
- High morbidity and mortality if not diagnosed and treated promptly 2, 3
- Treatment requires long-term antimicrobial therapy with antipseudomonal coverage 1, 4
- Surgical debridement may be necessary in some cases 4
Red Flags Requiring Immediate Attention
- Pain out of proportion to examination findings 2
- Cranial nerve deficits, especially facial nerve involvement 2, 4
- Previously diagnosed otitis externa not responding to appropriate therapy 2
- Presence of risk factors (diabetes, immunosuppression, advanced age) with severe ear symptoms 2, 3
Early recognition of these symptoms and prompt referral to an otolaryngologist is crucial for preventing complications and improving outcomes in patients with malignant otitis externa 2.