Acute-phase inflammatory response in idiopathic sudden deafness: pathogenic implications

Abstract

The acute-phase inflammatory response in the peripheral bloodstream can be an expression of transient cerebral ischaemia in idiopathic sudden deafness. For this, a neurological and otorhinolaryngological examination of each patient, performing tests on audiometry, and tympanometry, haemogram, and cranial magnetic resonance were performed. The acute-phase inflammatory response manifests as an increased neutrophil/lymphocyte ratio that is detected 48-72 hours after the appearance of sudden deafness. This study shows that there is an acute-phase response in the peripheral bloodstream with an increased neutrophil/lymphocyte ratio as an expression of an inflammatory process that can be caused by transient cerebral ischaemia in sudden deafness. In addition, the increased neutrophil/lymphocyte ratio can rule out a viral origin of sudden deafness, since a viral infection lowers the neutrophil count and increases the lymphocyte count, thus reducing the neutrophil/lymphocyte ratio. These findings aid in understanding the pathogenic mechanisms involved in sudden deafness and offer better treatment to the patient.

Figure 1

Individual values for the neutrophil/lymphocyte ratio (N/L) in patients with idiopathic sudden deafness (n = 41). Each point corresponds to the day on which the patient sought emergency treatment. Day 0 indicates the appearance of sudden deafness. The dotted line shows normal values. (Spearman's correlation coefficient (Rho) = −346; P = .009).

Figure 2

Mean ± standard error for the neutrophil/lymphocyte ratio (N/L) in patients with sudden deafness during the first week. Day 0 indicates the appearance of sudden deafness. The dotted line shows normal values. (Mann-Whitney U test. 0 versus 2: P = .032. 1 versus 2: P = .005. 2 versus 5: P = .043).