Hearing screening analysis in children exposed to the Zika virus

Abstract

Purpose: to analyze the results of neonatal hearing screening examinations in newborns with and without microcephaly, exposed to the Zika virus, without other risk indicators for hearing loss, and verify the association between screening results, sample characteristics, and the gestational trimester when exposure took place. Methods: a descriptive cross-sectional study. Subjects included in the study had no risk indicator for hearing loss other than microcephaly, and presented, along with their mothers, positive RT-PCR results, respectively at birth and during pregnancy. The transient evoked otoacoustic emission and brainstem auditory evoked potential examinations were applied by the researcher between March 2016 and December 2017. Newborns failed the screening when they failed at least one retest in at least one ear. The data were descriptively analyzed, using the Fisher exact test; p-values equal to or lower than 0.05 were considered significant. Results: out of the 45 subjects, 30 (66.7%) were females, 6.7% were likely to have sensorineural hearing loss, with or without auditory neuropathy spectrum disorder - which was possibly present in only one ear of one of these three subjects. Failure in the screening was statistically significant in subjects with at least one of the congenital Zika syndrome characteristics and subjects with subcortical calcification and brain cortex thinning, macular chorioretinal atrophy with focal pigmentary mottling, and hypertonia with symptoms of extrapyramidal involvement. The gestational trimester of exposure was associated with screening results. Conclusion: the responses in screening point to the possibility of hearing loss in newborns with and without microcephaly, whereas the presence of microcephaly was not significant to examination failures. Exposure in the first gestational trimester indicated a possible relationship with screening failures.