Longitudinal stability of JCV antibody index in Natalizumab treated people with multiple sclerosis.

OBJECTIVE: The aim of this study was to evaluate the evolution of JCV index over time in Natalizumab treated people with multiple sclerosis. MATERIALS AND METHODS: We retrospectively reviewed antibody index values from pwMS who were treated with Natalizumab for greater than six months and had at least two antibody results available between 2011 and 2019. Survival analysis was performed on those who were JCV index value negative at baseline to evaluate time to seroconversion. In pwMS who had index values available at 48 and/or 96 months post Natalizumab initiation, t-tests were performed to evaluate change in index over time. RESULTS: 1144 JCV antibody index results were available for 132 pwMS. Median time to seroconversion based on survival analysis was 103 months. Annualised seroconversion rate was 5.8%. Initial antibody index and rate of seroconversion did not differ with regards to age or gender. Antibody index increased significantly over time on treatment for the cohort as a whole, initial antibody index (0.27) to final antibody testing (0.86), t(131)=6.45, p<.0005. There was a significant increase in those with initial positive index value, between first (0.95) and final index (2.14), t(33) = 4.85, p<.0005 over a median of 77 months. CONCLUSIONS: In those who were seronegative at baseline there is a long median duration of treatment with Natalizumab prior to seroconversion. In individuals with positive JCV antibody index at treatment initiation, antibody index increases over time.

Neonatal hearing screening of high-risk infants using automated auditory brainstem response: a retrospective analysis of referral rates.

OBJECTIVE: The past decade has seen the widespread introduction of universal neonatal hearing screening (UNHS) programmes worldwide. Regrettably, such a programme is only now in the process of nationwide implementation in the Republic of Ireland and has been largely restricted to one screening modality for initial testing; namely transient evoked otoacoustic emissions (TEOAE). The aim of this study is to analyse the effects of employing a different screening protocol which utilises an alternative initial test, automated auditory brainstem response (AABR), on referral rates to specialist audiology services. METHODS: A retrospective analysis was performed of all neonatal hearing screening in Letterkenny General Hospital over 5 years, from January 2008 to December 2012, which was confined to infants possessing one or more known risk factors for permanent childhood hearing impairment. 1,163 infants were screened using AABR during this period and subsequent re-test and referral rates to specialist audiology services were examined. RESULTS: Of the infants screened, 50 (4.3 %) failed the initial AABR. A further 16 of these (32 %) failed the repeat AABR, resulting in an overall referral rate to specialist audiology services of 1.38 %. CONCLUSION: Our results demonstrate strikingly low overall referral rates in this cohort, falling well below both the international benchmark and the initial results of the Irish UNHS programme. This provides a convincing argument for examining AABR as a potential alternative to TEOAE in the nationwide UNHS.