Tumor Necrosis Factor-Alpha and Interleukin-4 Levels in Patients With Idiopathic Sudden Sensorineural Hearing Loss

Abstract

Background and Objectives The pathogenesis of idiopathic sudden sensorineural hearing loss (ISSNHL), an otologic emergency disease, remains unclear. Several studies have attempted to illustrate the association between cytokines and ISSNHL. The purpose of this study was to evaluate the prognostic significance of various cytokines in patients with ISSNHL. Subjects and Method In this case-control study, a total of 55 patients with ISSNHL underwent treatment with oral prednisolone for 2 weeks. Serum cytokine levels, including interleukins (ILs) (IL-1a, IL-1b, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12), and tumor necrosis factors (TNF-α and TNF-β), were measured using human cytokine panels at first visit. Patient characteristics such as age, gender, the status of hypertension, diabetes mellitus, vertigo, time from onset to visit, and initial hearing levels were also evaluated. Results Serum levels of cytokines were correlated with the prognosis of ISSNHL patients. IL-4 ≥0.225 (pg/mL) and TNF-α ≥5.155 (pg/mL) were significantly associated with poor therapeutic outcomes (OR=44.317, p=0.015 and OR=269.465, p=0.006, respectively). In addition, age and initial hearing levels were also significant prognostic factors. Conclusion Patients’ age, initial hearing levels, and serum levels of IL-4 and TNF-α prior to treatment are associated with hearing recovery and can be used as prognostic factors for patients with ISSNHL.

The inflammatory and metabolic status of patients with sudden-onset sensorineural hearing loss

“…Only at visit 3 did it show a correlation with uric acid ( r = 0.404), a result that was probably not related to SSNHL. In contrast to IL-1F7, the TH2 cytokines IL-4 and IL-6 have already been described as being involved in processes associated with SSNHL ( 26 , 62 ). It is noteworthy that although our results showed no significant changes over the course of the visits, both cytokines showed a positive correlation at visit 2 ( r = 0.547).…”

“…It is noteworthy that although our results showed no significant changes over the course of the visits, both cytokines showed a positive correlation at visit 2 ( r = 0.547). The presence of these cytokines indicates pro-inflammatory processes, with IL-6 being associated with the response to infection and tissue damage ( 63 ) and IL-4 with the production of immunoglobulin E, regulation of cell proliferation and apoptosis ( 62 ). Our results suggest that IL-4 correlates not only with IL-6 but also with other pro- and anti-inflammatory cytokines across the 3 visits.…”

“…This suggests that IL-4 may play a wide-ranging role in the maintenance of immune regulation and does not change between visits. Although the systemic presence of IL-4 has been described in patients with SSNHL ( 62 ), the function of this cytokine in the inner ear is still unknown. The effect of interleukin-6, on the other hand, has been described both in peripheral blood and in cochlear studies.…”