AUDITORY EVALUATION IN A CASE OF HEARING LOSS IN AN INFANT WITH CONGENITAL ZIKA SYNDROME (CZS)

BackgroundThe Zika virus (ZIKV) was detected in Brazil in 2014. At the end of 2015 microcephaly was the first distinctive sign. By 2016, the first two cases of congenital Zika had been described, with a strong correlation between the virus and microcephaly.Case reportA male infant was born at 32 weeks gestation, weight 1,750 grams, cranial perimeter 26 cm. He remained in intensive care for 5 days for neonatal seizures, required oxygen therapy, and had early sepsis. After 11 days in hospital a diagnosis of microcephaly was made. At 12 months, hydrocephalus was identified by computed tomography, with calcification foci in the subcortical region, basal nuclei, cerebellum, and brainstem. These characteristics are typical of congenital zika syndrome (CZS). Audiological tests were done: immittanciometry (tympanometry and acoustic reflex), transient evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), click ABR, and frequency following response (FFR). In patients with ZIKV, radiological findings show distinctive calcifications at the gray–white matter junction and degrees of delayed cortical development. The findings here of no acoustic reflex and a reduction in otoacoustic emissions in both ears is a preliminary indication of outer hair cell involvement that could later lead to communication deficits. ABR responses showed hearing pathway impairment in both ears up to the brainstem, and diminished FFR responses point to possible difficulties in speech perception. The present case study adds to our knowledge of the effect of CZS on the auditory system and strengthens the recommendation that ZIKV be included as an indicator for risk of hearing loss.