Azathioprine reduces the risk of audiometric relapse in immune-mediated hearing loss

Intratympanic infliximab is a safe and effective rescue therapy for refractory immune-mediated hearing loss

PURPOSE

To determine the efficacy and safety of the intratympanic infiltration of infliximab at the hearing threshold of patients in follow-up for refractory immune-mediated hearing loss.

METHODS

17 patients were collected with relapses, despite maintenance treatment with oral azathioprine associated or not with oral prednisone at low doses (between 5 and 7.5 ml/day) or refractory relapses to previous intratympanic corticoid treatment being 19 affected ears infiltrated. We measured the hearing threshold by Pure-Tone Average (PTA) 500-3000 Hz, 125-8000 Hz and 250-8000 Hz in pre-infiltration (baseline) and follow-up 3 weeks post-infiltration with auditory threshold at frequencies 125-8000 Hz.

RESULTS

The average age was 50.68 years (±15.23 years). After the administration of intratympanic infliximab, an improvement of the hearing threshold was showed in the Pure-Tone Average (PTA) calculated at 500-3000 Hz (p = 0.004), 125-8000 Hz (p = 0.001) and 250-8000 Hz (p = 0.006). An immediate improvement in low frequencies also was observed: 125, 250 and 500 Hz (p = 0.009, p = 0.002 and p < 0.001 respectively) also at 1000 Hz (p = 0.004) and a persistence of the effect at 3 months in the low frequencies: 125 Hz (p = 0.020), 250 Hz (p = 0.006) and 500 Hz (p = 0.002).

CONCLUSIONS

Infliximab intratympanic infiltration improves the hearing threshold in patients with immune-mediated hearing loss. The effect of improving the hearing threshold is higher in low frequencies and persists within 3 months of the infiltration. The administration of intratympanic infliximab is an effective and safe technique.

The Role of Autoimmunity in the Pathogenesis of Sudden Sensorineural Hearing Loss

Sudden sensorineural hearing loss (SSHL) is a clinically common acute symptom in otolaryngology. Although the incidence of SSHL has increased around the world in recent years, the etiology of the disease is still unclear. It has been reported that infections, ototoxic drugs, membrane labyrinth rupture, carcinomas, circulatory system diseases, autoimmune diseases, brain lesions, mental diseases, congenital or inherited diseases, and so on, are all risk factors for SSHL. Here, we discuss the autoimmune mechanisms behind SSHL, which might be induced by type II–IV allergic reactions. We also introduce the main immunosuppressive medications that have been used to treat SSHL, which will help us to identify potential targets for immune therapy.