低ウイルス量でも発生しうるラッサ熱による難聴に対する有望な治療アプローチ：症例報告

Lassa fever is a viral haemorrhagic illness endemic in West Africa, with Nigeria accounting for a significant proportion of global cases. While most patients recover, sensorineural hearing loss (SNHL) is a serious and often overlooked post-infectious complication. We present the case of a 13-year-old girl who developed sudden profound right-sided SNHL shortly after recovering from Lassa fever, despite a high cycle threshold (Ct) value on PCR, indicating low viral load. She was treated with intravenous mannitol and hydrocortisone, along with oral betahistine and neurovite, and demonstrated notable improvement in hearing over a one-month period. Follow-up revealed subclinical involvement of the contralateral ear, emphasizing the risk of bilateral progression. This case underscores that significant auditory sequelae can occur even at low viral loads and highlights the potential benefits of early pharmacologic intervention. It also reinforces the urgent need for routine hearing assessment and auditory rehabilitation in Lassa fever survivors.