Auditory Brainstem Responses (ABR) in neonates with hyperbilirubinemia

The technique of ABR testing was applied to 25 infants with neonatal hyperbilirubinemia at levels exceeding that for exchange transfusion, in an attempt to study potential influence of bilirubin toxicity on the auditory brainstem pathway. The test was performed at a mean conceptional age of 40.4 ± 0.6 weeks just after discharge. Twenty normal term neonates of comparable birth weights and conceptional ages, who had no hyperbilirubinemia, were also examined for comparison. Fifty six percent (n = 14) of the hyperbilirubinemic neonates had, some abnormality in the ABR pattern, the major one being a transient increase in the threshold of wave V (7, fail-30; 5, fail-45). Wave V, however, was consistently present at 30 dBnHL click stimulus in all the normal neonates (pass 30; normal threshold). Further, mean ABR latencies (wave III, V) and 1-V interpeak latency (brainstem conduction time) were significantly prolonged in jaundiced neonates as compared with controls (P < 0.01). ABR changes were strongly correlated with the serum bilirubin levels (P < 0.001). On follow up retesting at 3 months, however, all infants were found to have normal ABR latencies and threshold. Neonatal jaundice was associated with significant transient aberrations pf ABR, suggestive of a transient toxic brainstem encephalopathy.     

Ligurian experience on neonatal hearing screening: clinical and epidemiological aspects

AIM: Early identification and rehabilitation of newborns with congenital hearing impairment (HI) by Universal Neonatal Hearing Screening (UNHS). METHODS: The neonatal population was divided into two groups: babies with No Audiological Risk (NAR), and babies With Audiological Risk (WAR). NAR neonates underwent OAE testing, and in case of a doubtful (Refer) result, ABR testing was carried out. All WAR newborns underwent ABR testing within the third month of life. RESULTS: Between February 1, 2002 and December 31, 2004, UNHS was carried out on 32 502 newborns at the 13 regional birth centres, representing 98.7% of the whole regional neonatal population. The prevalence of HI in the population we tested was estimated at about 1 per thousand, while Bilateral Hearing Impairment (BHI) was estimated at 0.65 per thousand. A 3.7% prevalence of HI and a 2.8% prevalence of BHI was observed among the WAR population. Median age at the end of the diagnostic procedures was 6.7 months in the WAR population and 6.9 months in the NAR population. CONCLUSIONS: Our project is based on two levels of testing, which resulted in a 0.28% false-positive rate with 100% sensitivity and 99% specificity. Our screening is the first Italian experience that has been extended to a whole region and the results prove that regional neonatal hearing screening is feasible.     

VASOACTIVE INTESTINAL PEPTIDE (VIP) IN PRETERM AND TERM NEONATES

ABSTRACT. There is a little information on vasoactive intestinal peptide (VIP) in the neonatal period. We have measured plasma concentrations of this biologically important peptide in 159 preterm infants and 98 term neonates. Preterm neonates during the first four days of life had plasma VIP concentrations which were five times greater than the levels in 12 healthy adult controls (9.6±0.7 pmol/1, mean ± S. E. M., compared with 1.95±0.5 pmol/l, p <0.001), and these elevated concentrations persisted throughout the neonatal period. In contrast term infants on the sixth day of life, had plasma VIP concentrations only half those seen in preterm infants at the same post natal age ( p <0.001). Bottle-fed term infants had higher VIP levels than those who were breast fed (5.6±0.4 vs. 4.3±0.4, p <0.05). Plasma VIP concentrations did not change following a feed in any of the groups of neonates studied. The high plasma levels of VIP described may indicate a reduced neuropepitide clearance mechanism in neonates or alternatively, suggest a hitherto unrecognised role for this peptide hormone in the neonatal period.     

Congenital cytomegalovirus infection: association between virus burden in infancy and hearing loss

OBJECTIVE: To determine the relationship between the virus burden in infancy and hearing loss in congenital CMV infection. STUDY DESIGN: A cohort of 76 infants with congenital cytomegalovirus (CMV) infection identified by means of newborn virologic screening was monitored for outcome. The amount of infectious CMV was analyzed in urine specimens obtained during early infancy. Peripheral blood (PB) samples obtained during early infancy were available from 75 children and CMV DNA was quantitated with a real-time quantitative polymerase chain reaction. RESULTS: Infants with clinical abnormalities at birth (symptomatic congenital CMV infection) had higher amounts of CMV in urine (P = .005) and CMV DNA in PB (P = .001) than infants with no symptoms. Eight children with and 4 children without symptoms had hearing loss. Among children without symptoms, those with hearing loss had a significantly greater amount of CMV in urine (P = .03) and PB virus burden (P = .02) during infancy than those with normal hearing. Infants with < 5 x 10(3) pfu/mL of urine CMV and infants with < 1 x 10(4) copies/mL of viral DNA in PB were at a lower risk for hearing loss. CONCLUSION: In children with asymptomatic congenital CMV infection, hearing loss was associated with increased amounts of urine CMV and PB CMV DNA during early infancy.     

RESPIRATORY INSUFFICIENCY SYNDROME (RIS) IN PRETERM INFANTS WITH GESTATIONAL AGE OF 32 WEEKS AND LESS

ABSTRACT: Carlsson, J. and Svenningsen, N. W. (Department of Paediatrics, University Hospital, Lund, Sweden). Respiratory insufficiency syndrome (RIS) in preterm infants with gestational age of 32 weeks and less. Neonatal management and follow-up study. Acta Paediatr Scand, 64: 813, 1975.–The clinical entity of respiratory insufficiency syndrome (RIS), i.e. irregular breathing leading to recurrent apnea and bradycardia in an otherwise healthy preterm infant, has been studied in respect of symptomathology and management with intensive case including ventilatory support. During a 4-year period 26 of 103 infants with gestational age 32 weeks and mean birth weight 1304 g (range 710 to 1830 g) developed RIS. In most infants the initial apnea occurred after 2 and before 72 hours post delivery but in some infants later. Because of progressive hypoxemia and acidosis IS of the 26 RIS infants required IPPV treatment. The 76 % survival rate of RIS infants seems to justify intensive care with ventilatory support even in the smallest preterm infants with RIS, especially as the follow-up study performed at 15 months to 3 ½ years of age showed neurological sequelae in only 3 of 20 surviving babies, i.e. 15 % sequelae rate.     

Universal neonatal hearing screening: the Siena (Italy) experience on 19,700 newborns

BACKGROUND: Hearing loss (HL) is likely to be the most common congenital abnormality in humans, with a reported prevalence of 1 to 3 per 1000 live births. Early detection and intervention is critical to prevent the adverse consequences of a delayed diagnosis on speech, language and cognitive development. As 33-50% of all congenital HLs cannot be detected in a selective hearing risk, use of universal neonatal hearing screening (UNHS) programs is expanding. AIMS: We tested the value of a UNHS protocol, based on a two-stage strategy of Transient Evoked Otoacoustic Emissions (TEOAEs) in all infants, followed by diagnostic auditory brainstem response (ABR) testing in those infants who did not meet TEOAE pass criteria and those infants at high risk for hearing loss. METHODS: TEOAES (292 DP Echoport OAE Analyzer) served as the initial screen, followed by diagnostic ABR (Amplaid MK12) in newborns that did not meet pass criteria for TEOAEs. Additionally, all infants at high audiologic risk according to the Joint Committee on Infant Hearing received a diagnostic ABR evaluation. Of 21,125 total live births, 19,700 were tested (April 1, 1998-July 31, 2006). Accuracy of the UNHS strategy in predicting congenital HL was evaluated by calculating sensitivity, specificity, positive predictive value and negative predictive value. RESULTS: Prevalence for all HLs in the neonatal period was 1.78/1000 l.b. (35/19,700), with bilateral HL in 1.42/1000 l.b. (28/19,700) [low risk rate: 0.43/1000 l.b. (8/18,356); high risk infants rate: 14.88/1000 l.b. (20/1344)]. All the HL infants were diagnosed <3 and received intervention <6 months age. ROC curves results showed 100% sensitivity (95% C.I.: 89.0-100) and 99.3% specificity (95% C.I.: 99.2-99.4) of the two-stage strategy in detecting congenital HLs [area under the ROC curve: 0.997 (95% C.I.: 0.995-0.997)]. CONCLUSIONS: (1) The epidemiology of congenital HLs widely justifies UNHS; (2) a two-stage TEOAE and diagnostic ABR screening for congenital HL is feasible, minimally invasive and accurate in the early detection of congenital HL; and (3) a congenital HL screening strategy based exclusively on the use of TEOAEs should always consider the possibility of false negative cases.     

General movements in the first fourteen days of life in extremely low birth weight (ELBW) infants

Objective

To assess the quality of general movements (GMs) in the first fourteen days of life in relation to obstetric and postnatal risk factors and neurodevelopmental outcome in extremely low birth weight (ELBW) infants.

Study design

The GMs of nineteen infants were assessed on days 2, 4, 6, 10 and 14 with Prechtl's method. Additionally, detailed GM assessment produced optimality scores (OSs). GMs and the OSs were related to obstetric and postnatal data and to neurodevelopmental outcome at 18 months.

Results

GMs and OSs fluctuated substantially during the first fourteen days of life. Most infants had abnormal GMs, especially poor repertoire (PR) GMs. No relation was found between GMs and obstetric factors. Regarding postnatal factors, septicaemia correlated to hypokinesia (H) and artificial ventilation correlated to a lower OS.

Conclusions

Due to physiological disturbances the quality of GM in ELBW infants fluctuates substantially during the first fourteen days of life. Abnormal GMs, especially PR GMs, are mostly seen for the same reason. Septicaemia and artificial ventilation are associated with deterioration of the GMs (lower OSs), and in case of septicaemia also with hypokinesia.