Effect of Meconium Staining Amniotic Fluid on Fetal Outcome.

Meconium-stained amniotic fluid is the passage of meconium by a fetus in utero during the antenatal period or in labour. It has for long been considered to be a bad predictor of fetal distress and meconium aspiration syndrome (MAS). The objective of this study was to find out the fetal outcome of MSAF and clear amniotic fluid. This cross- sectional comparative study was carried out in Upazilla Health Complex, Palash, Narshingdi from July 2016 to June 2017. A total of 100 pregnant women among them 50 women with MSAF and 50 women with clear liquor were studied to see the record of ANC, mode of delivery and fetal outcome by APGAR score. Study showed that among MSAF group 76.0% (n=38) had irregular ANC and 24.0% (n=12) had regular ANC whereas in clear liquor 86.0% (n=43) had regular ANC 14.0% had irregular ANC. Among MSAF (50 cases) thick meconium was in 20 cases (40.0%) and thin meconium was in 30 cases (60.0%). Regarding mode of delivery 52.0% (n=26) MSAF cases had instrumental delivery and Caesarean section compared to 24.0% (n=12) in clear liquor group. Regarding thick MSAF among 40.0% (n=20), (n=14) had low APGAR score and (n=6) had normal score at one minute and (n=9) low APGAR score and (n=11) normal score at five minutes. In clear liquor, among 100.0% (n=50), 20.0% (n=10) had low APGAR score and 80.0% (n=40) had normal score at one-minute and at five minutes 8.0% (n=4) had low APGAR score and 92.0% (n=46) had normal score. Among MSAF 26.0% (n=13) were admitted to SCBU compare to 12.0% (n=6) in clear liquor group. The mean SCBU stay was 3.1 days in MSAF whereas 1.2 days in clear liquor. Among MSAF babies 4.0% (n=2) had MAS compared to no MAS in clear liquor group. Regarding Survivalist 92.0% (n=46) were alive in MSAF whereas 100.0% all (n=50) were alive in clear liquor group.

Enfermedad de Hirschsprung no sindrómica por variante en el gen RET / Non-syndromic Hirschsprung’s disease as a result of a RET gene variant

Introducción: La enfermedad de Hirschsprung (EH) se caracterizapor la ausencia de células ganglionares en los plexos submucoso y mientérico del intestino grueso, resultante de deficiencias en la migracióny diferenciación de las células de la cresta neural entérica durante laembriogénesis. Es una condición multifactorial, con más de 11 genesidentificados en su patogénesis, incluyendo el protooncogén RET.Caso clínico: Se presenta el caso de dos hermanos con EH de colontotal, cuyo padre también padeció la enfermedad, y en quien se encontróuna variante potencialmente patogénica en el gen RET.Comentarios: El diagnóstico prenatal mediante pruebas genéticaspermite decisiones informadas y la planificación de cuidados para elneonato afectado, reduciendo demoras en el diagnóstico y tratamiento,y minimizando las complicaciones a largo plazo. La identificación demutaciones como la variante en el gen RET destaca la importancia delenfoque genético en la comprensión y manejo de la EH.(AU)

Introduction: Hirschsprung’s disease (HD) is characterized by theabsence of ganglion cells in the submucosal and myenteric plexuses ofthe colon as a result of disorders in the migration and differentiationof enteric neural crest cells during embryogenesis. It is a cross-factorcondition, with more than 11 genes identified in its pathogenesis, including the RET proto-onco gene.Case report: We present the case of two siblings with total colonHD where a potentially pathogenic variant of the RET gene was found.Their father also had this condition.Discussion: Prenatal diagnosis through genetic testing allows forinformed decisions and care planning for the newborn, thus reducin delayed diagnosis and treatment, and minimizing long-term complications. Mutations such as the RET gene variant highlight the importanceof the genetic approach in understanding and managing HD.(AU)

Does prenatal diagnosis of meconium peritonitis have the better recovery? A single-center over 10 years of experience.

OBJECTIVE: To evaluate whether infants with prenatal diagnosis of meconium peritonitis (MP) have a poorer prognosis. METHODS: A retrospective analysis of data from infants treated with surgery from January 2008 to December 2020 was conducted. The patients were divided into prenatal diagnosis group and postnatal diagnosis group based on the timing of diagnosis. The intraoperative and postoperative parameters of the two groups of patients were compared. RESULTS: A total of 71 cases of MP were included in the study, with 48 cases in the prenatal diagnosis group and 23 cases in the postnatal diagnosis group. The comparison of preoperative indicators between the two groups of patients showed no statistically significant differences in baseline (p > 0.05). Intraoperative indicators, including blood loss, anastomosis, retained intestinal tube length and excised intestinal tube length, showed no statistically significant differences between the two groups (p > 0.05). However, the postnatal diagnosis group had a significantly shorter operation time than the prenatal diagnosis group (p < 0.05). Postoperative indicators, including fasting time, albumin usage, complications, and abandonment or mortality rates, show no difference (p > 0.05). Nevertheless, the postnatal diagnosis group exhibited significantly shorter hospital stay and time to first bowel movement compared to the prenatal diagnosis group (p < 0.05). CONCLUSION: Prenatal diagnosis of meconium peritonitis is associated with increased surgical complexity, prolonged hospital stay, and delayed recovery of intestinal function. However, there is no evidence of higher mortality or more complications compared to infants diagnosed postnatally, and there is no significant difference in long-term prognosis.

First Insight into Fetal Exposure to Legacy and Emerging Plasticizers Revealed by Infant Hair and Meconium: Occurrence, Biotransformation, and Accumulation.

Epidemiological studies have demonstrated the embryonic and developmental toxicity of plasticizers. Thus, understanding the in utero biotransformation and accumulation of plasticizers is essential to assessing their fate and potential toxicity in early life. In the present study, 311 infant hair samples and 271 paired meconium samples were collected at birth in Guangzhou, China, to characterize fetal exposure to legacy and emerging plasticizers and their metabolites. Results showed that most of the target plasticizers were detected in infant hair, with medians of 9.30, 27.6, and 0.145 ng/g for phthalate esters (PAEs), organic phosphate ester (OPEs), and alternative plasticizers (APs), and 1.44, 0.313, and 0.066 ng/g for the metabolites of PAEs, OPEs, and APs, respectively. Positive correlations between plasticizers and their corresponding primary metabolites, as well as correlations among the oxidative metabolites of bis(2-ethylhexyl) phthalate (DEHP) and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), were observed, indicating that infant hair retained the major phase-I metabolism of the target plasticizers. While no positive correlations were found in parent compounds or their primary metabolites between paired infant hair and meconium, significant positive correlations were observed among secondary oxidative metabolites of DEHP and DINCH in hair and meconium, suggesting that the primary metabolites in meconium come from hydrolysis of plasticizers in the fetus but most of the oxidative metabolites come from maternal-fetal transmission. The parent compound/metabolite ratios in infant hair showed a decreasing trend across pregnancy, suggesting in utero accumulation and deposition of plasticizers. To the best of our knowledge, this study is the first to report in utero exposure to both parent compounds and metabolites of plasticizers by using paired infant hair and meconium as noninvasive biomonitoring matrices and provides novel insights into the fetal biotransformation and accumulation of plasticizers across pregnancy.

Magnitude of meconium stained amniotic fluid and associated factors among women who gave birth in North Shoa Zone hospitals, Amhara Region, Ethiopia 2022.

BACKGROUND: The presence of meconium-stained amniotic fluid is one of the causes for birth asphyxia. Each year, over five million neonatal deaths occur worldwide because of meconium-stained amniotic fluid and other causes, of which 90% are due to birth asphyxia. The aim of this study was to assess the magnitude of meconium-stained amniotic fluid and associated factors among women who gave birth in North Shoa Zone Hospitals, Amhara Region, Ethiopia, 2022. MATERIALS AND METHODS: An institutional-based cross-sectional study was employed. We used 610 women who gave birth at North Shoa Zone Hospitals, Amhara region, Ethiopia. The study was conducted from June 8 to August 8, 2022. Recruitment for the study was made using a multistage sampling procedure. Fifty percent of the study hospitals were randomly selected, and proportional allocation was done. Participants were selected from the sampling frame, labour and delivery register book, using a systematic random sampling approach. The first person was selected at random, while the remaining individuals were selected at every two "K" intervals across all hospitals. An interview-administered structured questionnaire and chart review checklist were used to gather the data that were entered into Epi-Data Version 4.6 and exported to SPSS. Logistics regression was employed, and a p-value <0.05 was considered statistically significant. RESULT: The magnitude of meconium-stained amniotic fluid was 30.3%. Women with a normal hematocrit level were 83% less likely to develop meconium-stained amniotic fluid. Women whose mid-upper arm circumference value was less than 22.9cm (AOR = 1.9; 95% CI: 1.18-3.20), obstructed labour (AOR = 3.6; 95% CI: 1.48-8.83), prolonged labour ≥ 15 hr (AOR = 7.5; 95% CI: 7.68-13.3), premature rapture of membrane (AOR = 1.7; 95% CI: 3.22-7.40), foetal tachycardia (AOR = 6.2; 95% CI: 2.41-16.3), and Bradycardia (AOR = 3.1; 95% CI: 1.93-5.28) showed a significant association with meconium-stained amniotic fluid. CONCLUSION: The present study revealed that the magnitude of meconium-stained amniotic fluid in North Shoa Zone is nearly one-third. A normal hematocrit level is a preventive factor for meconium-stained amniotic fluid, and a MUAC value <22.9 cm, obstructed and prolonged labour, PROM, bradycardia, and tachycardia are factors associated with meconium-stained amniotic fluid.

Analysis of the clinical diagnosis and treatment of fetal meconium peritonitis.

BACKGROUND: The purpose of this study was to improve diagnostic and therapeutic standards by examining the clinical features, treatment, and prognosis of fetal meconium peritonitis (FMP), as well as the diagnostic efficacy of ultrasound for FMP. METHODS: The clinical data of 41 infants and pregnant women diagnosed with meconium peritonitis (MP) and treated at the Fujian Maternal and Child Health Hospital from January 2013 to January 2020 were analyzed retrospectively. Clinical data, imaging data, complications, treatment strategies, pregnancy outcomes, neonatal prognoses, and follow-up outcomes were all analyzed. RESULTS: The MP prenatal diagnosis rate was 56.1% (23/41), the neonatal surgery rate was 53.7% (22/41), and the survival rate was 85.4% (35/41). Intraperitoneal calcification (23 pregnant women, 56.1%), intestinal dilatation (13 pregnant women, 31.7%), peritoneal effusion (22 pregnant women, 53.7%), intraperitoneal pseudocyst (7 pregnant women, 17.1%), and polyhydramnios were diagnosed via prenatal ultrasound (18 pregnant women, 43.9%). Twenty-two pregnant women were assigned to the surgical treatment (operation) group, while 18 were assigned to the conservative treatment group. In the operation group, there were 9 cases of ileal atresia (40.9%), 7 cases of jejunal atresia (31.8%), 2 cases of atresia at the jejunum-ileum junction (9.1%), 2 cases of ileal perforation (9.1%), 1 case of ileal necrosis (4.5%), and 1 case of adhesive obstruction (4.5%). There was no statistically significant difference (p > .05) in the occurrence of various prenatal ultrasound findings by etiology. CONCLUSION: Multiple prenatal ultrasound markers have been identified for MP. To improve the efficacy of newborn treatment for FMP and reduce neonatal mortality, dynamic monitoring of ultrasound image alterations and strengthened integrated perinatal management are necessary.

A common trajectory of gut microbiome development during the first month in healthy neonates with limited inter-individual environmental variations.

The early development of the gut microbiome is governed by multiple factors and has significantly long-term effects on later-in-life health. To minimize inter-individual variations in the environment, we determined developmental trajectories of the gut microbiome in 28 healthy neonates during their stay at a postpartum center. Stool samples were collected at three time points: the first-pass meconium within 24 h of life, and at 7 and 28 days of age. Illumina sequencing of the V3-V4 region of 16S rRNA was used to investigate microbiota profiles. We found that there was a distinct microbiota structure at each time point, with a significant shift during the first week. Proteobacteria was most abundant in the first-pass meconium; Firmicutes and Actinobacteria increased with age and were substituted as the major components. Except for a short-term influence of different delivery modes on the microbiota composition, early microbiome development was not remarkably affected by gravidity, maternal intrapartum antibiotic treatment, premature rupture of membranes, or postnatal phototherapy. Hence, our data showed a similar developmental trajectory of the gut microbiome during the first month in healthy neonates when limited in environmental variations. Environmental factors external to the host were crucial in the early microbiome development.

Assessment of Fetal Exposure and Elimination of Perfluoroalkyl and Polyfluoroalkyl Substances: New Evidence from Paired Serum, Placenta, and Meconium Samples.

Multiple pieces of evidence have shown that prenatal exposure to perfluoroalkyl and polyfluoroalkyl substances (PFASs) is closely related to adverse birth outcomes for infants. However, difficult access to human samples limits our understanding of PFASs transport and metabolism across the human placental barrier, as well as the accurate assessment of fetal PFASs exposure. Herein, we assess fetal exposure to 28 PFASs based on paired serum, placenta, and meconium samples. Overall, 21 PFASs were identified first to be exposed to the fetus prenatally and to be metabolized and excreted by the fetus. In meconium samples, 25 PFASs were detected, with perfluorooctane sulfonate and perfluorohexane sulfonic acid being the dominant congeners, suggesting the metabolism and excretion of PFASs through meconium. Perfluoroalkyl sulfonic acids might be more easily eliminated through the meconium than perfluorinated carboxylic acids. Importantly, based on molecular docking, MRP1, OATP2B1, ASCT1, and P-gp were identified as crucial transporters in the dynamic placental transfer of PFASs between the mother and the fetus. ATSC5p and PubchemFP679 were recognized as critical structural features that affect the metabolism and secretion of PFASs through meconium. With increasing carbon chain length, both the transplacental transfer efficiency and meconium excretion efficiency of PFASs showed a structure-dependent manner. This study reports, for the first time, that meconium, which is a noninvasive and stable biological matrix, can be strong evidence of prenatal PFASs exposure.

Clinical significance of true umbilical cord knot: a propensity score matching study.

OBJECTIVE: True umbilical cord knot (TUCK) is a rare finding that often leads to intensified surveillance and patient anxiety. This study sought to evaluate the incidence, risk factors, and obstetric and neonatal outcomes of TUCK. METHODS: A retrospective cohort study was conducted at a tertiary university medical center in 2007-2019. Patients with singleton pregnancies diagnosed postnatally with TUCK were identified and compared to women without TUCK for obstetric and neonatal outcomes using propensity score matching (PSM). RESULTS: TUCK was diagnosed in 780 of the 96,766 deliveries (0.8%). Women with TUCK were older than those without TUCK (32.57 vs. 31.06 years, P < 0.001) and had higher gravidity (3 vs. 2, P < 001) and a higher rate of prior stillbirth (1.76% vs. 0.43%, P < 0.01). Following covariate adjustment, 732 women with TUCK were compared to 7320 matched controls. TUCK was associated with emergency cesarean delivery due to non-reassuring fetal heart rate (2.54% vs. 4.35%, P = 0.008, OR 1.71, 95%CI 1.14-2.56) and intrapartum meconium-stained amniotic fluid (19.26% vs. 15.41%, P = 0.022, OR 1.31, 95%CI 1.04-1.65). Neonatal outcomes were comparable except for higher rates of 1-min Apgar score < 7 and neonatal seizures in the TUCK group. The stillbirth rate was higher in the TUCK group, but the difference was not statistically significant (1.23% vs 0.62%, P = 0.06, OR 1.96, 95%CI 0.96-4.03). CONCLUSIONS: TUCK has several identifiable risk factors. Pregnant women with TUCK may cautiously be informed of the relatively low risks of major obstetric or perinatal complications. The lower occurrence of stillbirth in the TUCK group warrants further study.

Meconium Concentrations of Pesticides and Risk of Hypospadias: A Case-Control Study in Brittany, France.

BACKGROUND: Hypospadias is a male genital tract defect for which an increase in prevalence has been documented over the last few decades. A role for environmental risk factors is suspected, including prenatal exposure to pesticides. OBJECTIVES: To study the risk of hypospadias in association with multiple pesticide measurements in meconium samples. METHODS: The Brittany Registry of Congenital Anomalies (France) conducted a case-control study between 2012 and 2018. Cases were hypospadias, ascertained by a pediatrician and a pediatric surgeon, excluding genetic conditions, following European Surveillance of Congenital Anomalies guidelines (N = 69). Controls (N = 135) were two male infants without congenital anomaly born after each case in the same maternity unit. Mothers in the maternity units completed a self-administered questionnaire, we collected medical data from hospital records, and medical staff collected meconium samples. We performed chemical analysis of 38 pesticides (parent compound and/or metabolite) by UHPLC/MS/MS following strict quality assurance/quality control criteria and blind to case-control status. We carried out logistic regression accounting for frequency-matching variables and major risk factors. RESULTS: Among the 38 pesticides measured, 16 (42%) were never detected in the meconium samples, 18 (47%) were in <5% of samples, and 4 (11%) in ≥5% of the samples. We observed an association between the detection of fenitrothion in meconium and the risk of hypospadias (OR = 2.6 [1.0-6.3] with n cases = 13, n controls = 21), but not the other pesticides. CONCLUSIONS: Our small study provides a robust assessment of fetal exposure. Fenitrothion's established antiandrogenic activities provide biologic plausibility for our observations. Further studies are needed to confirm this hypothesis.

Associations of maternal prenatal psychological symptoms and saliva cortisol with neonatal meconium microbiota: A cross-sectional study.

Alterations in the diversity and relative abundances of the gut microbiome have been associated with a broad spectrum of medical conditions. Maternal psychological symptoms during pregnancy may impact on offspring development by altering the maternal and the foetal gut microbiome. We aimed to investigate whether self-reported maternal anxiety, depressive symptoms, and distress as well as saliva cortisol levels in late pregnancy alter the bacterial composition of the infant's meconium. METHODS: A total of N = 100 mother-infant pairs were included. Maternal psychological symptoms were measured using psychological questionnaires (EPDS, PSS-10, STAI) at 34-36 weeks gestation and salivary cortisol was measured at 34-36 and 38 weeks gestation. Infant meconium samples were collected in the first five days postpartum and analysed using 16S rRNA amplicon sequencing. RESULTS: Correlations showed that lower alpha diversity of the meconium microbiome was significantly associated with increased maternal prenatal depressive symptoms in late gestation (τ = -0.15, p = .04). Increased saliva cortisol AUCg at T2 was significantly related to higher beta diversity of the meconium samples (Pr(>F) = 0.003*). Pseudomonas was the most abundant phylum and was associated with maternal saliva cortisol total decline. No other associations were found. CONCLUSIONS: Maternal prenatal depressive symptoms are associated with infant faecal microbiome alpha diversity, whereas maternal saliva cortisol AUCg is linked to increased beta diversity and total decline related to increased Psuedomonas. Future studies are warranted to understand how these microbiota community alterations are linked to child health outcomes.

Investigating prenatal and perinatal factors on meconium microbiota: a systematic review and cohort study.

BACKGROUND: The first-pass meconium has been suggested as a proxy for the fetal gut microbiota because it is formed in utero. This systematic review and cohort study investigated how pre- and perinatal factors influence the composition of the meconium microbiota. METHODS: We performed the systematic review using Covidence by searching PubMed, Scopus, and Web of Science databases with the search terms "meconium microbiome" and "meconium microbiota". In the cohort study, we performed 16 S rRNA gene sequencing on 393 meconium samples and analyzed the sequencing data using QIIME2. RESULTS: Our systematic review identified 69 studies exploring prenatal factors, immediate perinatal factors, and microbial composition in relation to subsequent health of infants but gave only limited comparative evidence regarding factors related to the composition of the meconium microbiota. The cohort study pointed to a low-biomass microbiota consisting of the phyla Firmicutes, Proteobacteria and Actinobacteriota and the genera Staphylococcus, Escherichia-Shigella and Lactobacillus, and indicated that immediate perinatal factors affected the composition of the meconium microbiota more than did prenatal factors. CONCLUSIONS: This finding supports the idea that the meconium microbiota mostly starts developing during delivery. IMPACT: It is unclear when the first-pass meconium microbiota develops, and what are the sources of the colonization. In this systematic review, we found 69 studies exploring prenatal factors, immediate perinatal factors, and microbial composition relative to subsequent health of infants, but there was no consensus on the factors affecting the meconium microbiota development. In this cohort study, immediate perinatal factors markedly affected the meconium microbiota development while prenatal factors had little effect on it. As the meconium microbiota composition was influenced by immediate perinatal factors, the present study supports the idea that the initial gut microbiota develops mainly during delivery.

High-sensitivity neonatal urine drug testing has similar positivity rates to meconium for detecting in utero exposure to methamphetamine and cocaine.

Current guidelines recommend universal screening for substance use disorders in obstetric patients, and neonatal drug testing is also frequently performed. Meconium is often the preferred specimen type to detect neonatal drug exposure due to a longer window of detection compared to urine, but most laboratories send out meconium testing to specialized reference laboratories, which can delay results for several days or more. Here, we evaluate a rapid and definitive liquid chromatography-tandem mass spectrometry method for neonatal urine drug testing and compare results obtained using this method to paired meconium drug testing in 1,424 neonates for amphetamines, cocaine, cannabinoids, opiates, oxycodone and phencyclidine. Urine testing showed equivalent sensitivity to current meconium methods for detecting in utero exposure to amphetamines and cocaine.

Effects of prenatal alcohol exposition on cognitive outcomes in childhood and youth: a longitudinal analysis based on meconium ethyl glucuronide.

BACKGROUND: Prenatal alcohol exposure (PAE) has been linked to severe, adverse child outcomes. However, little is known regarding subclinical outcomes of low/moderate PAE and its longitudinal consequences, especially regarding neurophysiological and neurocognitive development. A newborn biomarker of PAE, meconium ethyl glucuronide (EtG), has been shown to predict cognitive impairments in primary-school-aged children. The current study investigated the ongoing effects of subclinical PAE in adolescence. METHODS: A sample of n = 96 mother-child dyads of the FRAMES/FRANCES cohort were classified into PAE/no PAE using EtG with a 10 ng/g cutoff. Mothers were recruited during pregnancy and children were assessed during primary-school age (M = 7.57, SD = 0.65, range: 6.00-9.92 years) and adolescence (M = 13.26, SD = 0.31, range: 12.79-14.20 years) on three levels: clinical (ADHD rating), neuropsychological (IQ score and performance in a go/nogo task), and neurophysiological (analysis of P3 event-related potentials (ERP) during said go/nogo task). Developmental outcomes and courses following PAE were assessed using rmANCOVAs, controlling for relevant confounders (socioeconomic status (SES), birth weight, and maternal psychopathology). RESULTS: Neurophysiological impairments emerged for exposed children in the form of diminished attentional resource recruiting in childhood and adolescence (reduced go-P3 amplitudes) with no differences in performance. Neuropsychological testing showed a reduced IQ score for both time points with dose-dependent effects in childhood. Clinical ADHD symptoms were not significantly affected. CONCLUSION: Subclinical PAE, as determined by meconium EtG, has negative developmental consequences on cognitive function that persist from childhood to adolescence. These findings suggest that there is no safe limit for alcohol consumption during pregnancy and that more thorough screening of alcohol consumption during pregnancy is necessary for early identification and treatment of at-risk children.

Meconium Transferrin and Ferritin as Markers of Homeostasis in the Developing Fetus.

The molecular mechanisms regulating homeostasis in the developing fetus have not been satisfactorily elucidated. Meconium contains substances accumulated in the fetal intestines. Measurements of transferrin and ferritin concentrations in meconium and assessment of transferrin-ferritin relationships could enhance knowledge about specific processes of the intrauterine period involving the two proteins and their effects on the development and growth of the fetus. Transferrin and ferritin concentrations were measured by ELISA in the homogenates of first meconium portions from 125 neonates. Higher birth weight was associated with lower ferritin concentrations in meconium (r = -0.22, p = 0.015). In neonates with a birth weight of more than 3750 g, there was a positive correlation between transferrin and ferritin concentrations (r = 0.51, p = 0.003). With meconium transferrin concentrations above 43.52 µg/g, a negative correlation between transferrin and ferritin was established (r = -0.37, p = 0.036), while with transferrin concentrations below 43.52 µg/g, the correlations between the birth weight and the meconium transferrin and ferritin concentrations were negative (r = -0.61, p < 0.001 and r = -0.43, p = 0.017, respectively). Measurements of transferrin and ferritin in meconium specimens create a new use for these common biomarkers to improve our understanding of the effects of homeostasis in utero on the fetal development and growth. Establishing reference ranges of meconium transferrin and ferritin concentrations and their association with the clinical parameters during pregnancy could aid in the assessment of the impact of intrauterine life on the health status of the neonate and its adaptation to extrauterine life.

[Calprotectin levels in meconium measured with an automated immunoassay (Liaison® XL)]. / Valeurs de référence de la calprotectine méconiale (immuno-dosage Liaison® XL).

A threshold of 50 µg fecal calprotectin per g stool sample (µg/g) is commonly used to diagnose chronic inflammatory bowel disease in adult patients and children over 4 years of age. In younger children, fecal calprotectin values are physiologically increased. For the first time, the objective of our study was to establish reference ranges in newborns for the measurement of meconium calprotectin with an automated assay (Liaison® XL, DiaSorin). A prospective study was conducted in 2022 in the Maternity Unit of the Clermont-Ferrand University Hospital, with the inclusion of full-term newborns without intestinal involvement. The quantitative automated Liaison® XL calprotectin assay was assessed on a panel of meconium samples. In our cohort of 132 term neonates, calprotectin values ranged from 21 to 855 µg/g of meconium (2,5th to 97.5th percentile) and the median value was 194 µg/g. In our cohort, only sex-related differences were observed for calprotectin values. No significant differences were found for the other factors studied (maternal or neonatal). Because of inter-individual variability, a sequential measurement of newborn calprotectin from meconium should be considered.