Letter to the Editors: The burden of neonatal jaundice and sepsis in developing countries

Abstract

Although prevailing adverse perinatal conditions in devel-oping countries are readily associated with mortality, theyalso portend significant risks for the well being of survivingchildren and their families. Measuring the full burden ofthese conditions besides the incidence of infant mortalityremains a continuing challenge because of the dearth oflongitudinal studies on the developmental profile of thesurvivors. The study by Gordon et al. (2005), althoughlimited to neonatal jaundice and neonatal sepsis, is animportant contribution to the much needed database forthis region and certainly complements more commonreports on the neurodevelopmental outcomes in pre-termor low-birthweight infants. However, the incidence ofpermanent hearing impairment would appear to have beenunder-reported because neither otoacoustic emissions(OAE) nor auditory brainstem response (ABR) evaluationwas conducted. As unconjugated hyperbilirubinaemia is anestablished risk factor for sensorineural hearing loss,objective hearing assessment would have been valuableespecially in the light of the growing trend towards earlyhearing detection and intervention.In my ongoing pilot programme on infant hearingscreening in Lagos, Nigeria consisting of a two-stagescreening with transient evoked OAE and automated ABRfollowed by confirmatory test with diagnostic ABR, six(21.4%) of the 28 full-term infants (total screened: 761infants 300 lmol/l) without sepsis andunderwent exchange blood transfusion. Two of these werekernicteric and had severe bilateral hearing loss with poorneck control. The third baby had mild bilateral hearing losswith no other noticeable neurological deficits. Two babieshad neonatal jaundice (<300 lmol/l) along with sepsis andwere found to have moderate bilateral hearing loss. Thisobservation may suggest that the presence of neonatalsepsis increases the risk of hearing loss where total serumbilirubin level is <300 lmol/l. Although this threshold isnot universal or absolute (Dennery et al. 2001), thisobservation warrants further investigation. The sixth babyhad neonatal jaundice of unknown severity, which wastreated with traditional medicine at the herbal home wherethe baby was born and was diagnosed with severeunilateral hearing loss.It was unlikely that most of these children would havebeen detected early enough for optimal intervention (JointCommittee on Infant Hearing 2000) solely throughparental suspicion/concern because hearing loss associatedwith jaundice characteristically affects the high frequencyregion which compromises speech discrimination andunderstanding rather than audibility (Newton 2001).The use of objective and age-appropriate screening tech-nologies should therefore be encouraged to identifyhidden sensory disorders more accurately especially whereearly detection enhances developmental outcomes.Bolajoko O. Olusanya