Fecal calprotectin concentration in neonatal necrotizing enterocolitis

Characteristics of fecal calprotectin as an early marker for suspected necrotizing enterocolitis in newborns exclusively fed maternal breast milk: a case-control study

Objective

Numerous studies have proposed using fecal calprotectin among many biomarkers associated with necrotizing enterocolitis (NEC) diagnosis. This study aimed to evaluate fecal calprotectin as an early marker for suspected NEC (stage 1) in infants fed exclusively breast milk.

Methods

We collected 20 stool samples from newborns admitted to the neonatal intensive care unit at Aswan University Hospital diagnosed with stage I NEC. We compared them with 20 samples from matched healthy newborns. Fecal calprotectin level was measured by enzyme-linked immunosorbent assay.

Results

Fecal calprotectin level was higher in cases than in the control group (P < 0.001). Also, there was a positive correlation between fecal calprotectin and C-reactive protein in the studied cases (P = 0.001). However, there were no correlations between fecal calprotectin and sex or postnatal age.

Conclusion

Fecal calprotectin levels increase in newborns with stage I NEC. Although not specific, its sensitivity suggests a role as a potential biomarker in the evaluation of suspected NEC.

Fecal calprotectin as a non-invasive marker for the prediction of post-necrotizing enterocolitis stricture

PURPOSE

This study aimed to evaluate the clinical utility of fecal calprotectin (FC) levels during the necrotizing enterocolitis (NEC) episode to predict the onset of post-NEC intestinal stricture.

METHODS

The medical records of patients with NEC treated from April 2020 to April 2022 were recorded for this study. FC was quantified at the acute phase of NEC. FC levels were compared in patients with or without intestinal stricture. Receiver operating characteristics (ROC) analysis was constructed to determine optimal cut-offs of FC for post-NEC intestinal stricture.

RESULTS

A total of 50 infants with NEC were enrolled in this study and 14 (28%) of them eventually developed intestinal stricture. All children with intestinal stricture underwent one-stage surgery and all made it through the follow-up period alive. The median FC level was 1237.55 (741.25, 1378.80) ug/g in patients with intestinal stricture and it was significantly higher than that in the non-stricture group [158.30 (76.23, 349.13) ug/g, P < 0.001]. FC had good diagnostic accuracy for predicting intestinal stricture, according to ROC curve analysis, with an AUC area of 0.911. At an optimal cut-off value of 664.2 ug/g, sensitivity and specificity were 85.71% and 91.67%, respectively.

CONCLUSION

As a non-invasive parameter, FC has excellent efficacy and accuracy in predicting post-NEC intestinal stricture. Increased FC levels at the acute phase of NEC were associated with the development of intestinal stricture.

Postnatal Dynamics and Clinical Associations of Fecal Calprotectin in Very Preterm Infants: Implications for Necrotizing Enterocolitis and Feeding Intolerance

INTRODUCTION

To elucidate the postnatal dynamics and clinical associations of fecal calprotectin (FC) in very preterm infants, with a focus on necrotizing enterocolitis (NEC) and feeding intolerance (FI).

METHODS

We performed a prospective observational cohort study in infants with a gestational age of <32 weeks or birth weight <1,500 g with weekly feces collection. The relationships between FC, NEC, and FI were investigated, adjusting for demographic and clinical factors.

RESULTS

A total of 1,086 fecal samples were collected from 194 preterm infants. Postnatal FC levels of non-NEC infants were highly variable and followed an age-dependent patterned progression. FC levels were elevated in patients with NEC before and at NEC onset, distinguishing them from non-NEC infants and those at sepsis onset. Among infants without NEC or sepsis, those with FI exhibited lower FC concentrations throughout hospitalization and displayed a significant delay in reaching high FC levels after meconium compared with non-FI infants. The age to reach the first high nonmeconial FC levels was positively associated with the time to achieve full enteral feeding.

DISCUSSION

Postnatal FC dynamics among premature infants followed a patterned progression but were disturbed in patients with NEC and FI. Because of the high variations, the use of FC levels in NEC diagnosis should be implemented with caution in clinical practice. FC may help understand FI and feeding progression in very preterm infants. Further research is needed to validate these findings and explore the potential clinical applications of FC in this population.

Fecal Calprotectin Levels Dynamics in Newborns with High-Risk of Necrotizing Enterocolitis

Background. Necrotizing enterocolitis (NEC) is severe gastrointestinal disease in newborns, its early clinical symptoms are nonspecific. Fecal сalprotectin (Cp) is considered as one of the early biomarkers of NEC, thus, its use in newborns is poorly known.

Objective. The aim of the study is to evaluate clinical significance of fecal Cp measuring as an early NEC marker in newborns. Methods. The prospective cohort observational study included high-risk newborns (gestational age (GA) ˂ 33 weeks and/or body weight ˂ 1500 g) and moderate risk newborns (GV≥ 33 weeks at suspicion on NEC) of NEC admitted to the neonatal intensive care unit on the 1st day of life. The Cp level was studied via immune colorimetric method on the 3rd and 7th days of life in high-risk children and in all children at NEC manifestation. All patients were divided into 2 main subgroups after the end of the follow-up period: newborns with developed NEC (a) and children without NEC (b). Obtained Cp values were compared between these subgroups.

Results. There were no statistically significant differences in Cp levels at the 3rd and 7th days of life in the high-risk group of children with NEC and without NEC. However, it was noted that children without NEC showed a decrease in Cp levels on the 7th day, while children with NEC manifestation, indeed, had increased levels. Cp levels did not differ in the moderate risk group.

Conclusion. Single measurement of Cp level in newborns of any GA is uninformative towards the NEC prognosis and diagnosis. However, evaluation of the Cp level dynamics at the 7th day of life compared to the 3rd day of life may be considered as a promising non-invasive method for prognosis of NEC manifestation in premature infants (GA<33 weeks). 

Trends of fecal calprotectin levels and associations with early life experience in preterm infants

Background

Preterm infants are at risk for severe infections due to their immature immune systems. Factors such as early life pain/stress experiences and feeding may influence immune activation and maturation of immune systems. However, the underlying mechanism remains unclear. Fecal calprotectin (FCP) is a noninvasive surrogate biomarker of mucosal inflammation in the gastrointestinal tract and has been used in detecting intestinal inflammation in specific pediatric gastrointestinal disorders.

Objective

To describe the longitudinal trajectory of FCP levels in preterm infants and investigate the contributing factors that are associated with FCP levels.

Design

A longitudinal study design was used.

Settings

Preterm infants were recruited from 2 neonatal intensive care units (NICU) of a children's medical center in the North-eastern US.

Methods

Preterm infants were followed during their first 4 weeks of NICU hospitalization. Stool samples were collected twice per week to quantify the FCP levels. Cumulative pain/stress experiences and feeding types were measured daily. A linear mixed-effect model was used to examine the associations between FCP levels and demographic and clinical characteristics, cumulative pain/stress, and feeding over time.

Results

Forty-nine preterm infants were included in the study. Infants' FCP levels varied largely with a mean of 268.7±261.3 µg/g and increased over time. Preterm infants experienced an average of 7.5±5.0 acute painful procedures and 15.3±20.8 hours of chronic painful procedures per day during their NICU stay. The mean percentage of mother's own milk increased from the first week (57.1±36.5%) to the fourth week (60.7±38.9%) after birth. Elevated FCP concentration was associated with acute and cumulative (chronic) pain/stress levels, mother's own milk, non-White race, and higher severity of illness score.

Conclusions

FCP levels were elevated in preterm infants with wide interindividual and intraindividual variations. Cumulative pain/stress during the NICU hospitalization, feeding, race, and health status may influence FCP concentrations in early life that may be associated with inflammatory gut processes.

The perinatal factors that influence the excretion of fecal calprotectin in premature-born children

This study aimed to provide additional information on the influence of perinatal factors on fecal (f)-calprotectin values in preterm infants. Calprotectin was determined from the first spontaneous stool (analyzed on the Alegria device by using the enzyme-linked immunosorbent assay [ELISA] method) obtained from neonates at a mean age of 3.41 ± 2.44 days of life. We analyzed 114 subjects who had a body weight of 1847.67 ± 418.6 g and were born at a gestational age of 32.6 ± 2.43 weeks, without intestinal and other congenital anomalies or any diseases other than those related to premature birth. The values of f-calprotectin are in a positive correlation with female subjects, intrauterine growth restriction, significant ductus arteriosus, enteral feeding intolerance, postnatal prolonged use of broad-spectrum antibiotics, and values ​​of bicarbonates (analyzed in a sample of capillary arterial blood). Measurement of f-calprotectin in the first 7 days after birth can help to early detect the intestinal distress or early staging of necrotizing enterocolitis in premature infants.

Biomarkers of gut injury in neonates - where are we in predicting necrotising enterocolitis?

Despite advances in neonatal care Necrotising Enterocolitis (NEC) continues to have a significant mortality and morbidity rate, and with increasing survival of those more immature infants the population at risk of NEC is increasing. Ischaemia, reperfusion, and inflammation underpin diseases affecting intestinal blood flow causing gut injury including Necrotising Enterocolitis. There is increasing interest in tissue biomarkers of gut injury in neonates, particularly those representing changes in intestinal wall barrier and permeability, to determine whether these could be useful biomarkers of gut injury. This article reviews current and newly proposed markers of gut injury, the available literature evidence, recent advances and considers how effective they are in clinical practice. We discuss each biomarker in terms of its effectiveness in predicting NEC onset and diagnosis or predicting NEC severity and then those that will aid in surveillance and identifying those infants are greatest risk of developing NEC.

[Role of fecal calprotectin in the diagnosis of neonatal necrotizing enterocolitis: a Meta analysis]

OBJECTIVE

To study the value of fecal calprotectin (FC) in the diagnosis of neonatal necrotizing enterocolitis (NEC) through a Meta analysis.

METHODS

Web of Science, Cochrane Library, PubMed, Embase, China National Knowledge Infrastructure, Weipu Periodical Database, Wanfang Data, Chinese Biomedical Literature Database were searched for related studies published up to May 2020, with manual search as supplementation. The QUADAS criteria were used to evaluate the quality of the articles included. Meta-DiSc 1.4 and Stata 15.0 software were used to perform the Meta analysis, including the evaluation of specificity, sensitivity, likelihood ratio, and diagnostic odds ratio. The sensitivity analysis and heterogeneity testing were performed, and the summary receiver operating characteristic (SROC) curve and Fagan diagram were plotted.

RESULTS

A total of 15 articles were enrolled, involving 1 719 neonates. Among these articles, 4 had low quality, 2 had high quality, and the rest had medium quality. There was high heterogeneity between studies, and there was no threshold effect or publication bias. The random effects model analysis showed that FC had a pooled specificity of 0.80 (95%CI:0.78-0.82) and a sensitivity of 0.86 (95%CI:0.83-0.89) in the diagnosis of NEC, with a negative likelihood ratio of 0.19 (95%CI:0.14-0.26), a positive likelihood ratio of 4.71 (95%CI:3.57-6.23), and a diagnostic odds ratio of 29.56 (95%CI:17.98-48.61). The area under the SROC curve was 0.9131 and the Q^* index was 0.8456. The Fagan diagram showed that the post-test probability of NEC indicated by negative FC was 13%, while that indicated by positive FC was 86%. The Meta regression analysis showed that the heterogeneity came from other non-threshold factors.

CONCLUSIONS

FC has high potential and efficiency in the early diagnosis of NEC. FC measurement can be used for the diagnosis of NEC, but it should be combined with clinical manifestations and other related laboratory examinations.

Faecal calprotectin and gut microbiota do not predict enteropathy in very preterm infants

Aim

Very preterm birth is associated with a high risk of enteropathies. Diagnosis is challenging, especially in mild forms, leading to unnecessary periods of cessation of enteral feeding. This study aimed at establishing a prognosis score of enteropathy combining clinical parameters and faecal calprotectin concentration.

Methods

This prospective multicentric study included preterm neonates born at a gestational age of 33 weeks or less. Stools were collected weekly until hospital discharge, and daily in case of digestive events for calprotectin measurement (ELISA and immunochromatography) and microbiota analyses (16S rRNA gene sequencing).

Results

Among the 121 neonates included, 21 experienced at least one episode of enteropathy, mainly mild forms. By ELISA testing, median faecal calprotectin was 88 (8‐798) µg/g faeces. No statistically significant association was found between the outset of enteropathy and maternal and neonatal characteristics, and calprotectin levels. The agreement between ELISA and immunochromatography assay was moderate (intra‐class correlation coefficient 0.58, 95%CI [0.47‐0.66]). Comparison of species diversity and relative bacterial abundance profiles between infants with or without enteropathy revealed no specific alterations associated with enteropathy.

Conclusion

The study failed to propose a prognostic score of enteropathy, probably due the large inter‐ and intra‐individual variability of faecal calprotectin in very preterm neonates.

Time of Onset of Necrotizing Enterocolitis and Focal Perforation in Preterm Infants: Impact on Clinical, Surgical, and Histological Features

Objective: There is no gold standard test for diagnosis of necrotizing enterocolitis (NEC). Timing of onset is used in some definitions and studies in an attempt to separate NEC from focal intestinal perforation (FIP) with 14 days used as a cutoff. In a large, detailed data set we aimed to compare NEC and FIP in preterm infants born <32 weeks gestation, presenting before 14 days of life in comparison to cases presenting later. Design: Infants with NEC or FIP when parents had consented to enrollment in an observational and sample collection study were included from 2009 to 2019. Clinical, surgical, histological, and outcome data were extracted and reviewed by each author independently. Patients/Episodes: In 785 infants, 174 episodes of NEC or FIP were identified of which 73 (42%) occurred before 14 days, including 54 laparotomies and 19 episodes of medically managed NEC ("early"). There were 56 laparotomies and 45 episodes of medically managed NEC presenting on or after 14 days age ("late"). Results: In early cases, 41% of laparotomies were for NEC (22 cases) and 59% for FIP (32 cases), and in late cases, 91% of laparotomies (51 cases) were for NEC and 9% (five cases) were for FIP. NEC presenting early was more likely to present with an initial septic presentation rather than discrete abdominal pathology and less likely to have clear pneumatosis. Early cases did not otherwise differ clinically, surgically, or histologically or in outcomes compared with later cases. FIP features did not differ by age at presentation. Conclusions: Although most FIP occurred early, 14% occurred later, whereas almost one third (29%) of NEC cases (surgical and medical) presented early. Infant demographics and surgical and histological findings of early- and late-presenting disease did not differ, suggesting that early and late cases are not necessarily different subtypes of the same disease although a common pathway of different pathogenesis cannot be excluded. Timing of onset does not accurately distinguish NEC from FIP, and caution should be exercised in including timing of onset in diagnostic criteria.

Dynamic Changes of Fecal Calprotectin and Related Clinical Factors in Neonates

Objective: Fecal calprotectin (FC) has been widely used for a clinical marker of intestinal inflammation in children and adults. However, the clinical usefulness has not been determined in neonates. The purpose of this study was to investigate the change of FC and associated clinical factors in neonates. Methods and Materials: In total, 146 neonates among 472 admissions to our NICU between 2018 and 2019 were included, and 242 stool samples were collected. FC was measured in the first, second, and third-fourth week after birth, respectively, using commercial ELISA. The clinical characteristics were reviewed from medical records. Statistical analyses were performed to analyze associated factors regarding on changes of fecal calprotectin. Results: A wide range from 5.5 to 6,000 mg/kg of FC was observed in neonates. FCs during neonatal period were not correlated with the gestational age at birth or birth weight. The meconial calprotectin was higher than FCs after 2 weeks of age (n = 134, 418.06 vs. 243.12 in the second week and 259.58 in the third week after birth). Meconial calprotectin was associated with birth weight and meconium stained amniotic fluid. FC during the neonatal period decreased with postnatal week (-464.93 ± 158.02 at third-fourth week after birth compared with the 1st week, P = 0.004) and breast milk (-337.27 ± 150.51 compared with formula milk, P = 0.026). Conclusion: Fecal calprotectin tended to decrease with postnatal week during the neonatal period, and breast milk could affect more decrease of FC.

Recent Potential Noninvasive Biomarkers in Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is a rare but devastating gastrointestinal disease that predominately affects preterm neonates. Numerous studies have revealed that NEC is strongly associated with very low birth weight, degree of prematurity, formula feeding, infection, hypoxic/ischemic injury, and enteric dysbiosis. Given these clinical associations, the search for a deeper understanding of disease pathogenesis has led to an intense interest in the discovery and development of noninvasive biomarkers of NEC from stool, urine, and serum. Biomarkers for NEC may serve at least two general purposes of urgent unmet need: to improve diagnostic accuracy and disease prediction and to reveal the mechanism of the disease. This review will provide an overview of recent research focused on clinical NEC and highlight the advances that were made within the past five years towards the development of noninvasive diagnostic biomarkers.

The role of fecal calprotectin in pediatric disease

Fecal calprotectin (FC) is a calcium- and zinc-binding protein of the S100 family, mainly expressed by neutrophils and released during inflammation. FC became an increasingly useful tool both for gastroenterologists and for general practitioners for distinguishing inflammatory bowel disease (IBD) from irritable bowel syndrome. Increasing evidences support the use of this biomarker for diagnosis, follow-up and evaluation of response to therapy of several pediatric gastrointestinal diseases, ranging from IBD to nonspecific colitis and necrotizing enterocolitis. This article summarizes the current literature on the use of FC in clinical practice.

Reference intervals for stool calprotectin in preterm neonates and their utility for the diagnosis of necrotizing enterocolitis

OBJECTIVE

Calprotectin is an antimicrobial protein found in stool when released by granulocytes. We sought to create stool calprotectin reference ranges in preterm neonates and to evaluate whether levels exceeding the upper reference interval are diagnostic for necrotizing enterocolitis (NEC).

STUDY DESIGN

Stool calprotectin was measured in premature neonates without gastrointestinal pathology to create reference intervals. For comparison, levels from infants undergoing "rule out NEC" evaluations were plotted on these reference intervals.

RESULTS

Stool calprotectin reference intervals were created according to gestational age at birth and corrected gestational age. Levels during "rule out NEC" evaluations were more often above the upper reference interval with NEC vs. those without NEC.

CONCLUSIONS

Stools from preterm neonates have a higher range of calprotectin than stools from healthy term neonates. In evaluating preterm neonates for NEC with stool calprotectin, a calprotectin upper reference interval that incorporates corrected gestational age best predicts the diagnosis of NEC.

Clinical significance of fecal calprotectin for the early diagnosis of abdominal type of Henoch-Schonlein purpura in children

The objective of this study is to explore the value of fecal calprotectin (FC) for early screening of the abdominal type of Henoch-Schonlein purpura (AHSP) in children. The study cohort included 40 children with AHSP treated at Shengjing Hospital of China Medical University from November 2014 to November 2015, and 40 children hospitalized in the Division of Pediatric Orthopedics in the corresponding period were selected as a control group. Fresh fecal samples were collected in the acute phase of the first visit (FC1), 3 days after treatment (FC2), and 7 days after treatment (FC3) from the AHSP group and the control group. Calprotectin levels in the fecal samples were measured using an enzyme-linked immunosorbent assay. At the same time, gastrointestinal performance and the laboratory examination indicators white blood cell (WBC) count and C-reactive protein (CRP) level were recorded. The median levels of FC1 (3053 μg/g) and FC2 (2778.3 μg/g) were higher than in the control group (102.5 μg/g), with significant differences among the three groups (p < 0.001). FC levels gradually decreased in remission, and the level of FC3 on day 7 was close to that of the control samples (p > 0.05). When the optimal cut-off was 264.5 μg/g, the area under the receiver operating characteristic (ROC) curve of FC for diagnosis of AHSP was 0.961 with a corresponding sensitivity and specificity of 93.1 and 87.5%, respectively. The levels of FC in children with AHSP were positively correlated with WBC count (r _s = 0.688) and CRP value (r _s = 0.513). The area under the ROC curve of WBC count for screening AHSP was 0.785 when the optimal cut-off value was 11.1 × 10⁹/L with a corresponding sensitivity and specificity of 81.5 and 62.5%, respectively. The area under the ROC curve of CRP was 0.963 when the optimal cut-off value was 5.72 mg/dL with a corresponding sensitivity and specificity of 88.9 and 100%, respectively. Comparisons of FC, WBC count, and CRP level as diagnostic indicators of AHSP showed that the sensitivity of FC was higher than that of the WBC count and CRP level, and its diagnostic value was better than that of the WBC count. The levels of FC began to increase in the early stages of AHSP, showing a decreasing tendency in remission and tending to be within a normal range after a week or so. For the early diagnosis of AHSP, FC with a cut-off level of 264.5 μg/g has good sensitivity and specificity. The sensitivity of FC is better than that of the traditional inflammation indicators CRP and WBC count, and its diagnostic performance is better than WBC count; FC can be suitable as a new marker for the early diagnosis of AHSP.

Biomarkers of necrotizing enterocolitis: a review of literature

Necrotizing enterocolitis (NEC) is among the most serious gastrointestinal emergency in very low birth weight (VLBW), extremely low birth weight (ELBW) and extremely low gestational age neonates (ELGAN), affecting 7-14% of these neonates. Despite extensive research, the underlying aetiology of NEC still remains blurred. Due to high mortality, morbidity and its delayed presentation, early detection of NEC is considered to be lifesaving. A number of biomarkers have been studied for early detection and prediction of severity of NEC but till date, no ideal marker has been discovered. Molecular techniques like proteomic and metabolomic have recently emerged in the field for the development of biomarkers for early detection and understanding the pathophysiology of NEC. We did literature search for identifying all biomarkers that have been used for the detection of NEC and, in this review article, we discuss these biomarkers along with the available current evidence.

Elevated fecal calprotectin levels during necrotizing enterocolitis are associated with activated neutrophils extruding neutrophil extracellular traps

OBJECTIVE

Neonates with necrotizing enterocolitis (NEC) have higher calprotectin levels in stool than do healthy neonates. However, it is not known whether high stool calprotectin at the onset of bowel symptoms identifies neonates who truly have NEC vs other bowel disorders.

STUDY DESIGN

Neonates were eligible for this study when an x-ray was ordered to 'rule-out NEC'. Stool calprotectin was quantified at that time and in a follow-up stool. Each episode was later categorized as NEC or not NEC. The location of calprotectin in the bowel was determined by immunohistochemistry.

RESULTS

Neonates with NEC had higher initial and follow-up stool calprotectin levels than did neonates without NEC. Calprotectin in bowel from neonates with NEC was within neutrophil extracellular traps (NETs).

CONCLUSION

At the onset of signs concerning for NEC, fecal calprotectin is likely to be higher in neonates with NEC. Calprotectin in their stools is exported from neutrophils via NETs.

Fecal calprotectin levels in preterm infants with and without feeding intolerance

OBJECTIVES

To assess the level of fecal calprotectin in preterm neonates with feeding intolerance, as well as to evaluate it as a marker of feeding intolerance and to determine a cut-off level of fecal calprotectin in feeding intolerance.

METHODS

Analytical, multicenter, case-control study, which was carried out in neonatal intensive care units in Egypt, in a period from August 1, 2014 to March 1, 2015 on 52 preterm neonates. Neonates were classified into two groups; a study group including 26 neonates who met inclusion criteria and a control group including 26 neonates for comparison.

RESULTS

Fecal calprotectin levels ranged from 3.9μg/g to 971.8μg/g, and there was a significant increase in fecal calprotectin in the study group when compared to the control group (334.3±236.6μg/g vs. 42.0±38.2μg/g, respectively) with moderate inverse significant correlation between fecal calprotectin and birth weight. Furthermore, there was moderate, significant correlation between fecal calprotectin and duration of breastfeeding range. On the other hand, there was no correlation between fecal calprotectin and post-natal age, gestational age, or volume of feeding. A cut-off at the 67.0μg/g level, with 100.0% sensitivity and 76.9% specificity, was considered.

CONCLUSION

Fecal calprotectin level increased significantly in neonates with feeding intolerance; it can be used to detect early cases with necrotizing enterocolitis in neonates, but this subject still needs more investigations on more patients.

Effect of Promoter Polymorphisms on Cytokine Concentration in Preterm Breast Milk and Subsequent Infant Outcomes

BACKGROUND

Breast milk concentrations of immune components are variable between women and interleukin (IL) differences may be associated with infant outcomes. Molecular mechanisms for milk variability remain unknown.

OBJECTIVE

The aims were to (1) examine the relationship between maternal IL genotypes and milk concentrations of IL4, IL6, and IL10, (2) describe the trajectories of milk IL change, (3) examine whether maternal IL genotypes predict IL trajectories and/or average weekly IL concentration, and (4) examine if weekly IL levels and/or IL trajectories are associated with infant outcomes.

METHODS

Milk aliquots were collected from each feeding of mother's own milk and pooled weekly. DNA was extracted from 1 sample of each mother's breast milk whey (n = 64), and single nucleotide polymorphisms (SNPs) of IL genes were genotyped. Milk IL concentrations were measured and trajectory analysis examined IL milk change over time. Multivariate breast milk IL concentration analyses controlled for gestational age and prepregnancy body mass index. Multivariate infant outcome (n = 73) analyses controlled for gestational age and the ratio of human milk to total milk.

RESULTS

Trajectory analysis resulted in linear group shapes, with 2 distinct subgroups in IL6 and 3 subgroups in IL4 and IL10. Trajectory groups trended toward significance with calprotectin, intraventricular hemorrhage, and blood transfusions. Multivariate analyses resulted in trending associations between maternal SNPs and subsequent IL6 and IL10 milk levels. There was a trending relationship between IL milk levels and both fecal calprotectin and intraventricular hemorrhage.

CONCLUSION

Maternal IL SNPs may affect IL breast milk levels and IL milk levels may be associated with infant outcomes.

The immunological landscape in necrotising enterocolitis

Necrotising enterocolitis (NEC) is an uncommon, but devastating intestinal inflammatory disease that predominantly affects preterm infants. NEC is sometimes dubbed the spectre of neonatal intensive care units, as its onset is insidiously non-specific, and once the disease manifests, the damage inflicted on the baby's intestine is already disastrous. Subsequent sepsis and multi-organ failure entail a mortality of up to 65%. Development of effective treatments for NEC has stagnated, largely because of our lack of understanding of NEC pathogenesis. It is clear, however, that NEC is driven by a profoundly dysregulated immune system. NEC is associated with local increases in pro-inflammatory mediators, e.g. Toll-like receptor (TLR) 4, nuclear factor-κB, tumour necrosis factor, platelet-activating factor (PAF), interleukin (IL)-18, interferon-gamma, IL-6, IL-8 and IL-1β. Deficiencies in counter-regulatory mechanisms, including IL-1 receptor antagonist (IL-1Ra), TLR9, PAF-acetylhydrolase, transforming growth factor beta (TGF-β)_1&2, IL-10 and regulatory T cells likely facilitate a pro-inflammatory milieu in the NEC-afflicted intestine. There is insufficient evidence to conclude a predominance of an adaptive Th1-, Th2- or Th17-response in the disease. Our understanding of the accompanying regulation of systemic immunity remains poor; however, IL-1Ra, IL-6, IL-8 and TGF-β₁ show promise as biomarkers. Here, we chart the emerging immunological landscape that underpins NEC by reviewing the involvement and potential clinical implications of innate and adaptive immune mediators and their regulation in NEC.

Calprotectin levels in necrotizing enterocolitis: a systematic review of the literature

BACKGROUND

Fecal calprotectin has been extensively investigated as a screening marker for the detection of necrotizing enterocolitis (NEC). However, there is a complete lack of consensus regarding its efficacy as a diagnostic test.

OBJECTIVE

The purpose of the present systematic review is to evaluate the effectiveness of fecal calprotectin as a screening marker for the detection of NEC.

MATERIALS AND METHODS

We conducted a systematic review of studies published in the Medline (1966-2016), Scopus (2004-2016), ClinicalTrials.gov (2008-2016), Cochrane Central Register of Controlled Trials CENTRAL (1999-2016), and Google Scholar (2004-2016) databases, combined with studies found in the reference lists of the included studies. All prospective and retrospective observational cohort studies were included.

RESULTS

Thirteen studies that included 601 neonates were identified in the international literature. The presence and severity of NEC was evaluated with the modified Bell's criteria. Ten studies found significantly elevated fecal calprotectin levels among infants with NEC (p < 0.05). One study found that this effect was observed irrespective of the stage of the disease. Five studies evaluated the efficacy of fecal calprotectin as a diagnostic test. The reported sensitivity ranged between 76 and 100 %, and the specificity varied from 39 to 96.4 %. However, the proposed cut-off values were not similar.

CONCLUSION

Current evidence suggests that fecal calprotectin is elevated in newborns suffering from NEC. However, its significance as an early screening marker remains unknown. Future studies are needed and should focus on the identification of specific cut-off values.

Serum Calprotectin: A Potential Biomarker for Neonatal Sepsis

INTRODUCTION

The correct diagnosis of neonatal sepsis is a relevant problem because sepsis is one of the most important causes of neonatal morbidity, mortality, and prolonged hospital stay. Calprotectin is an antimicrobial, calcium and zinc binding heterocomplex protein that could be used as a nonspecific marker for activation of granulocytes and mononuclear phagocytes. Calprotectin has been proposed for the diagnosis of inflammatory conditions. Our aim is to study serum calprotectin as a biomarker for neonatal sepsis diagnosis.

METHODS

41 (20 females, 21 males) infants who underwent blood culture due to suspected sepsis were enrolled in the study. Serum calprotectin was measured by a commercial ELISA assay (Calprest, Eurospital, Trieste, Italy). Statistical analysis was performed using the statistical software package Stata 13.1 (Stata Corporation, College Station, Texas, USA).

RESULTS

8 neonates (19.51%) showed sepsis with positive culture and 33 (80.49%) showed suspected sepsis. The optimal cut-off for calprotectin is 2.2 μg/mL with a sensitivity of 62.5% and a specificity of 69.7%.

CONCLUSIONS

Calprotectin may be considered a promising early, sensitive, specific marker of sepsis thanks to the importance of calprotectin in defense mechanisms and physiological functions of the immune system.