Atsuko Nakano

Cochlear Nerve Deficiency and Associated Clinical Features in Patients With Bilateral and Unilateral Hearing Loss

Objective To clarify the prevalence and clinical characteristics of cochlear nerve deficiency (CND) in patients with congenital bilateral and unilateral hearing loss. Study Design Retrospective case review. Setting Tertiary referral center. Patients One hundred fourteen children with bilateral and 56 children with congenital unilateral sensoneural hearing loss. Main Outcome Measures Review of medical records, audiologic tests, and imaging studies. Imaging studies were evaluated for the presence or absence of abnormalities in the bony cochlear nerve canal (BCNC), internal auditory canal (IAC), and inner ear. Results The prevalence of CND, whether unilateral or bilateral, was much higher in the unilateral than in the bilateral hearing loss group: 50% (28/56) versus 5.3% (6/114). Among the 6 children with bilateral hearing loss and CND, 2 had bilateral BCNC stenosis alone, 2 had bilateral BCNC stenosis and unilateral IAC stenosis, 1 had unilateral BCNC stenosis alone, and 1 had unilateral IAC stenosis alone. All 28 children with unilateral hearing loss and CND had BCNC stenosis, whereas 9 (32.1%) also had concurrent IAC stenosis. Three of the 6 children with CND and bilateral hearing loss and 5 of the 28 children with CND and unilateral hearing loss also had other inner ear abnormalities. Conclusion Our results suggest differences in the causes and mechanisms of CND in children with bilateral versus unilateral hearing loss.

The effect of Japanese cedar-specific immunotherapy on cytokine production in peripheral blood mononuclear cells

The most common cause of seasonal allergic rhinitis in Japan is the Japanese cedar (JC). Recently, a pullulan-conjugated antigen (CS-560) has been developed to reduce adverse effects and to enhance the effect of JC-specific immunotherapy (IT). If the mechanism of IT can be fully elucidated and the treatment can be used safely and with specificity, IT should be reconsidered as a superior treatment for JC pollinosis. Thirteen patients with JC pollinosis who received IT were compared to 10 patients who did not receive IT. All patients were followed through two pollen seasons by means of allergy diaries. Peripheral blood mononuclear cells (PBMC) were collected before IT and just before each pollen season, and these were stimulated with pollen extract. The concentrations of IL-4, IL-5, IL-13 and IFN- n in the culture supernatants were determined using an ELISA. Furthermore, messenger (m)RNA expressions of IL-4 and IL-5 from cultured PBMC were also studied. As a result of the allergy diaries, we confirmed the clinical efficacy of CS-560. The symptom-medication scores were significantly decreased by IT. The levels of IL-4, IL-5 and IL-13 declined only in the IT group. However, the level of IFN- n did not change in either group. IL-4 and IL-5 mRNA expressions were inhibited in the IT group compared to that in the non-IT group. In conclusion, specific IT for JC pollinosis using CS-560 clearly modified cytokine expression by PBMC.