Systemic Immune Inflammatory Index of Patients With Idiopathic Sudden Sensorineural Hearing Loss: Comparison of NLR and PRL Values

Abstract

Sudden sensorineural hearing loss (SSNHL) is sensorineural hearing loss of 30 dB or more in 3 consecutive frequencies within 3 days.The incidence rate is 5 to 20/100 000. It is commonly seen after 40 years of age. A detailed history taking and physical examination should be done for the differential diagnosis. The etiology is unknown in 85% of cases. The identifiable causes of SSNHL include autoimmune inner ear diseases like Behçet disease, Cogan syndrome, and systemic lupus erythematosus (SLE); infections like meningitis, Lyme disease, and syphilis; some neoplasms like vestibular schwannoma or cerebellopontine angle (CPA) tumors; neurological diseases like migraine, multiple sclerosis, and pontine ischemia; ear diseases like Meniere disease and otosclerosis; some ototoxic drugs like aminoglycosides and chemotherapeutic agents; trauma; and vascular diseases such as sickle cell anemia. Cases with unknown etiology are defined as idiopathic sudden sensorineural hearing loss (ISSNHL), which has vascular, viral, and immune theories. However, its etiopathogenesis has not yet been clearly delineated. In previous studies, inflammation has been found to play a role in SSNHL. Response to steroid therapy supports this theory. Clinical in vitro animal studies and human temporal bone studies support this etiology. For example, erythrocyte sedimentation rate is a nonspecific marker of inflammation. Erythrocyte sedimentation rate was found to be elevated in patient with ISSNHL in several studies.