Sudden Left Hearing Loss in a Diabetic Patient With Contrast Allergy and Limited MRI Access
54-year-old man presents 3 days after sudden onset of left hearing loss and tinnitus. He has no vertigo, facial weakness, or otorrhea. His medical history includes type 2 diabetes (HbA1c 8.9%) and stage 3a chronic kidney disease (eGFR 52). Ten years ago he developed urticaria after iodinated IV contrast. Otoscopy is normal bilaterally. Audiometry shows right PTA 18 dB and left PTA 72 dB with word recognition 36%; tympanometry is type A. An urgent care clinic started a methylprednisolone dose pack, and he asks whether he needs “a scan” and more steroids. He lives 3 hours from the nearest MRI, and his insurance requires prior authorization for MRI. He is afebrile, systemically well, and worried about missing work as a truck driver.
1. How would you define and treat this hearing loss, and how do his diabetes and renal function change your steroid plan?
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Sudden sensorineural hearing loss is defined as at least 30 dB across three contiguous frequencies within 72 hours; this patient has a 72 dB PTA, so the diagnosis is secure once conductive causes are excluded. The dose pack is inadequate. I would start prednisone 1 mg/kg/day (60 mg) for 10–14 days, with a taper only if needed, and monitor fasting glucose twice daily; diabetes is a relative, not absolute, contraindication. Because of CKD and brittle diabetes, I would add or prioritize intratympanic dexamethasone 10 mg/mL (0.5–1 mL) weekly for 3 weeks, which gives high cochlear levels with minimal systemic effect. I would not give antivirals. I would check baseline electrolytes, blood pressure, and HbA1c, and coordinate with his primary care physician. If he cannot monitor glucose reliably, intratympanic steroid alone is reasonable.
2. What imaging would you order, and how would you address the contrast allergy and access barrier?
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MRI of the brain and internal auditory canals with and without gadolinium is preferred to exclude vestibular schwannoma, meningioma, stroke, or demyelination. Prior urticaria to iodinated contrast does not absolutely contraindicate gadolinium, but because the reaction was urticarial I would premedicate with a corticosteroid and antihistamine or use a noncontrast heavily T2-weighted sequence (CISS/FIESTA), which can detect most retrocochlear masses. The access barrier does not justify skipping imaging; I would initiate prior authorization, document medical urgency, and arrange the study within 2 weeks. Temporal bone CT is not a substitute for MRI in SSNHL, though it may be used if MRI is impossible. If imaging remains delayed, I would continue treatment and follow audiometry closely.
3. What prognostic factors would you discuss, and what follow-up would you arrange?
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Prognosis is worse with profound loss, older age, vertigo, delayed treatment, and poor word recognition; this patient has two adverse features (70 dB and 36% WRS) but no vertigo and presents on day 3. I would repeat audiometry at 2 weeks and 3 months. If there is no improvement at 2–4 weeks, I would offer salvage intratympanic steroids. I would counsel that recovery is partial in many patients, that the contralateral ear should be protected from noise, and that follow-up MRI is mandatory even if hearing improves. He should not drive a truck until any dizziness and glucose control are stable.