The trend of urinary NT-proBNP in extremely low birth weight infants during the neonatal period

Background: NT-proBNP is a biomarker of interest in many cardiopulmonary diseases in extremely low birth weight (ELBW) Infants. However, there is a gap in knowledge about the trend of ELBW infant’s urinary NT-proBNP during the neonatal period. Aim: To determine the trend of urinary NT-proBNP during the first four weeks of life of an ELBW infant Study Design: We analyzed prospectively enrolled, 87 ELBW infants. Urinary NT-proBNP to creatinine ratios were measured on days 1-7, day 14, and day 28 of life. In addition, we plotted each study point's means to determine the trend of urinary NT-proBNP over the entire neonatal period. Data were analyzed using the Friedman ANOVA for comparative analysis of study points. Results: Urinary NT-proBNP/creatinine ratios were significantly elevated on days 1-7 (mean 2452, + 1518) than day 14 (mean 747, +176), and day 28 (mean149, +54), p=0.001. Overall, urinary NT-proBNP levels were highest during the days 1-3 (mean 3232+1255) and lowest on day 28 (mean149, +54). Conclusions: Urinary NT-proBNP levels are higher during the first week in ELBW infants with a downward trend during the neonatal period, with the lowest values at four weeks postnatal age. More studies are required to determine the clinical utility of this trend during and beyond the neonatal period.

357Infant pacifier sanitization and risk of food allergy: the Barwon Infant Study

Background Environmental microbial exposure and human gut microbiota play a role in development of the immune system and susceptibility to food allergy. Pacifier use has been inconsistently associated with allergy, but the association between sanitization and food allergy is unknown. We investigated the association between infant pacifier use, with a consideration of sanitization, and food allergy at age 1 in the Barwon Infant Study (BIS). Methods Questionnaire data were collected prospectively from pregnant mothers from the Barwon region of south-east Australia at baseline and at infant ages 1, 6, and 12 months. Pacifier sanitization was defined as the joint exposure of a pacifier and cleaning methods (antiseptic, mouth, tap water, boiling). Challenge-proven food allergy was determined at age 1. Results Any pacifier use at 6 months was associated with food allergy (aOR, 1.94; 95% CI, 1.04-3.61), but not at other ages. This overall association was driven by the joint exposure pacifier-antiseptic use (aOR, 5.90; 95% CI, 2.18-15.97) compared to no pacifier use. Among pacifier users, pacifier-antiseptic was still associated with food allergy (aOR, 3.88; 95% CI, 1.55-9.72) when compared to pacifier-no antiseptic use. Further, increased use of pacifier-antiseptic at 0, 1 or 2 interviews over the first 6 months was associated with higher food allergy risk (ptrend=0.005). Conclusions Joint exposure to antiseptics and pacifiers at 6 months increased the odds of food allergy, showing a trend with increased use over time. Key messages This is the first report of pacifiers used with antiseptic being positively associated with challenge-proven food allergy.

Receipt of infant HIV DNA PCR test results is associated with a reduction in retention of HIV-exposed infants in integrated HIV care and healthcare services: a quantitative sub-study nested within a cluster randomised trial in rural Malawi

Background Retention of HIV-infected mothers in integrated HIV and healthcare facilities is effective at reducing mother-to-child-transmission (MTCT) of HIV. In the context of Option B+, we examined maternal and HIV-exposed infant retention across three study arms to 18 months postpartum: mother-and-infant clinics (MIP), MIP with short-messaging service (MIP + SMS) and standard of care (SOC). In particular, we focused on the impact of mothers receiving an infant’s HIV PCR test result on maternal and infant study retention. Methods A quantitative sub-study nested within a cluster randomised trial undertaken between May 2013 and August 2016 across 30 healthcare facilities in rural Malawi enrolling HIV-infected pregnant mothers and HIV-exposed infants on delivery, was performed. Survival probabilities of maternal and HIV-exposed infant study retention was estimated using Kaplan-Meier curves. Associations between mother’s receiving an infant’s HIV test result and in particular, an infant’s HIV-positive result on maternal and infant study retention were modelled using time-varying multivariate Cox regression. Results Four hundred sixty-one, 493, and 396 HIV-infected women and 386, 399, and 300 HIV-exposed infants were enrolled across study arms; MIP, MIP + SMS and SOC, respectively. A total of 47.5% of mothers received their infant’s HIV test results < 5 months postpartum. Receiving an infant’s HIV result by mothers was associated with a 70% increase in infant non-retention in the study compared with not receiving an infant’s result (HR = 1.70; P-value< 0.001). Receiving a HIV-positive result was associated with 3.12 times reduced infant retention compared with a HIV-negative result (P-value< 0.001). Of the infants with a HIV-negative test result, 87% were breastfed at their final study follow-up. Conclusions Receiving an infant’s HIV test result was a driving factor for reduced infant study retention, especially an infant’s HIV-positive test result. As most HIV-negative infants were still breastfed at their last follow-up, this indicates a large proportion of HIV-exposed infants were potentially at future risk of MTCT of HIV via breastfeeding but were unlikely to undergo follow-up HIV testing after breastfeeding cessation. Future studies to identify and address underlying factors associated with infant HIV testing and reduced infant retention could potentially improve infant retention in HIV/healthcare facilities. Trial registration Pan African Clinical Trial Registry: PACTR201312000678196.

Gaze behaviour to lateral face stimuli in infants who do and do not receive an ASD diagnosis

Cerebral lateralisation of function is a common characteristic across vertebrate species and is positively associated with fitness of the organism, in humans we hypothesise that it is associated with cognitive fitness. This investigation evaluated the early development of lateralised gaze behaviour for face stimuli in infants at high and low risk for autism from the British Autism Sibling Infant Study (BASIS). The BASIS cohort includes a low risk group and three high-risk groups who at age 3 were developing (i) typically, (ii) atypically or (iii) had received a diagnosis for ASD. Using eye-tracking data derived from a face pop-out task at 6 and 14 months of age, all non-ASD groups showed a bias for stimuli on the left at both timepoints. At 6 months the ASD group demonstrated a preference for stimuli on the right and were slower than their neurotypical counterparts to look at faces on the left. However, by 14 months these differences disappear. Longitudinal associations between lateral looking behaviour at 6 months and language and motor ability at 14 months were also found. Results suggest that infants who go on to be diagnosed with autism exhibit early differences in gaze behaviour that may be associated with subsequent cognitive outcomes.