Intratympanic Dexamethasone Injection as Salvage Therapy for Refractory Bilateral Sudden Sensorineural Hearing Loss...

Bilateral sudden sensorineural hearing loss (BSSHL) is an uncommon otologic emergency that may occur as the initial manifestation of relapsed B-cell non-Hodgkin lymphoma complicated by hyperviscosity syndrome (HVS). Systemic Bruton tyrosine kinase (BTK) inhibition can reduce IgM levels but may be insufficient to reverse cochlear dysfunction. We present a 74-year-old woman with a history of small B-cell non-Hodgkin lymphoma who developed simultaneous bilateral profound sudden hearing loss secondary to clinically presumed Waldenström macroglobulinemia (WM). Serum IgM peaked at 53.21 g/L, and fundoscopic examination showed typical hyperviscosity retinopathy. Despite four weeks of treatment with zanubrutinib, hearing showed no improvement. Bilateral intratympanic dexamethasone (IT-Dex) injections (5 mg daily for 6 consecutive days) were administered as salvage therapy.The patient began to perceive sound on day 3 and showed significant hearing improvement by day 6. Pure-tone average thresholds improved by 15 dB in the right ear and 20 dB in the left ear. This case demonstrates that IT-Dex injection is an effective salvage intervention for refractory HVS-related BSSHL that is unresponsive to systemic BTK inhibitor therapy. Multidisciplinary collaboration between otolaryngologists and hematologists is essential for timely diagnosis and intervention.