[Hearing screening and diagnosis of hearing loss: high risk versus low risk neonates].
BACKGROUND
congenital hearing loss is a serious health problem affecting 1 to 3 out of 1000 neonates, and is the most common cause of neurosensorial defect; hearing screening helps to identifying early permanent childhood hearing loss (HL).


OBJECTIVE
to establish the percentage of hearing loss in newborns with and without risk factors through hearing screening.


METHODS
by using a cross-sectional design, a group of neonates with risk factors and a group without risk factors were included in a two-stage hearing screening program. The otoacoustic emissions (OAEs) procedure was done in the first stage and the automated auditory brain stem response (AABR) procedure in the second stage. The latter was performed only in children with abnormal results in the OAE procedure.


RESULTS
518 newborns were included in the hearing screening procedures; 220 neonates with risk factors and 298 without risk factors. 35 had + OAE test and the ABBR procedure helped to confirm that 30 neonates had hearing loss, 26 had bilateral HL; 10 had asymmetric HL; 4 had unilateral HL and 5 were false positives. The AABR procedure ascertained 17 HL cases with a threshold > 40 dB (86 per 100,000), 11 cases (55 per 100,000) in the risk group and 6 (30 per 100,000) in the non-risk group (p < 0.05). The main risk factors were prematurity, craniofacial anomalies, mechanical ventilation, prescription of amikacin and cytomegalovirus infection.


CONCLUSIONS
the two-stage hearing screening program ascertained that 5.7 % had HL. AABR (threshold > 40 dB) confirmed 17 (86 per 100,000) neonates with HL, which was more frequent in the risk group (5 %) than in the non-risk group (2 %; p < 0.05).
Hernández-Herrera
Ricardo Jorge
RJ
Departamento de Neonatología, Unidad Médica de Alta Especialidad (UMAE) 23, Instituto Mexicano del Seguro Social, Monterrey, Nuevo Leon, Mexico. richdzher@hotmail.com
Hernández-Aguirre
Luz María
LM
Castillo-Martínez
Norma E
NE
de la Rosa-Mireles
Natalia
N
Martínez-Elizondo
Jesús
J
Alcalá-Galván
Luis Gerardo
LG
Estrella-Garza
Martha del Carmen
Mdel C
Hernández-Núñez
Rogelio
R
Torcida-González
Miguel Eloy
ME
D034381:Hearing Loss / Q000175:diagnosis*; D006801:Humans; D007231:Infant, Newborn; D015997:Neonatal Screening; D012307:Risk Factors