Allergic gastroenteropathy in preterm infants

What is Known About Cow's Milk Protein Allergy in Preterm Infants?

Background: Cow's milk protein allergy (CMPA) is well described in term infants, as opposed to preterm infants. In preterm infants, CMPA shares many gastrointestinal symptoms with necrotizing enterocolitis (NEC). Objectives: To evaluate the presentation of CMPA in preterm infants and to investigate the different diagnostic and therapeutic options. Materials and Methods: We searched for the relevant literature using the medical databases PubMed, Web of Science, and the Cochrane Library. We performed a post hoc analysis on the 25 case reports included in this study. Results: Literature was scarce and heterogeneous. The majority of preterm infants with CMPA were exposed to bovine-based milk proteins before the development of symptoms. The most common clinical manifestations were bloody stools, vomiting, and abdominal distension. Of the 25 cases, only 7 (28%) retained human milk in their diet after diagnosis. In the larger studies, no study has human milk as primary feeding choice after diagnosis. Conclusions: Preterm infants exposed to a type of cow's milk-based formula in their first days of life have a higher risk of developing CMPA. Most of the preterm infants are no longer fed with human milk after the diagnosis of CMPA is made, which is in contrast with current nutrition guidelines in preterm infants. We strongly advocate that human milk with mothers on a cow's milk-free diet is the first choice of feed after the diagnosis of CMPA. Prospective studies are necessary to obtain more information regarding clinical presentation, diagnostic tools, and therapeutic approaches.

Protein supplementation of human milk for promoting growth in preterm infants

BACKGROUND

Preterm infants require high protein intake to achieve adequate growth and development. Although breast milk feeding has many benefits for this population, the protein content is highly variable, and inadequate to support rapid infant growth. This is a 2020 update of a Cochrane Review first published in 1999.

OBJECTIVES

To determine whether protein-supplemented human milk compared with unsupplemented human milk, fed to preterm infants, improves growth, body composition, cardio-metabolic, and neurodevelopmental outcomes, without significant adverse effects.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search Cochrane Central Register of Controlled Trials (CENTRAL 2019, Issue 8) in the Cochrane Library and MEDLINE via PubMed on 23 August 2019. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Published and unpublished RCTs were eligible if they used random or quasi-random methods to allocate hospitalised preterm infants who were being fed human milk, to additional protein supplementation or no supplementation.

DATA COLLECTION AND ANALYSIS

Two review authors independently abstracted data, assessed risk of bias and the quality of evidence at the outcome level, using GRADE methodology. We performed meta-analyses, using risk ratio (RR) for dichotomous data, and mean difference (MD) for continuous data, with their respective 95% confidence intervals (CIs). We used a fixed-effect model and had planned to explore potential causes of heterogeneity via subgroup or sensitivity analyses.

MAIN RESULTS

We included six RCTs, involving 204 preterm infants. The risk of bias for most methodological domains was unclear as there was insufficient detail reported. Low-quality evidence showed that protein supplementation of human milk may increase in-hospital rates of growth in weight (MD 3.82 g/kg/day, 95% CI 2.94 to 4.7; five RCTs, 101 infants; I² = 73%), length (MD 0.12 cm/wk, 95% CI 0.07 to 0.17; four RCTs, 68 infants; I² = 89%), and head circumference (MD 0.06 cm/wk, 95% CI 0.01 to 0.12; four RCTs, 68 infants; I² = 84%). Protein supplementation may lead to longer hospital stays (MD 18.5 days, 95% CI 4.39 to 32.61; one RCT, 20 infants; very low-quality evidence). Very low quality evidence means that the effect of protein supplementation on the risk of feeding intolerance (RR 2.70, 95% CI 0.13 to 58.24; one RCT, 17 infants), or necrotizing enterocolitis (RR 1.11, 95% CI 0.07 to 17.12; one RCT, 76 infants) remains uncertain. No data were available about the effects of protein supplementation on neurodevelopmental outcomes.

AUTHORS' CONCLUSIONS

Low-quality evidence showed that protein supplementation of human milk, fed to preterm infants, increased short-term growth. However, the small sample sizes, low precision, and very low-quality evidence regarding duration of hospital stay, feeding intolerance, and necrotising enterocolitis precluded any conclusions about these outcomes. There were no data on outcomes after hospital discharge. Our findings may not be generalisable to low-resource settings, as none of the included studies were conducted in these settings. Since protein supplementation of human milk is now usually done as a component of multi-nutrient fortifiers, future studies should compare different amounts of protein in multi-component fortifiers, and be designed to determine the effects on duration of hospital stay and safety, as well as on long-term growth, body composition, cardio-metabolic, and neurodevelopmental outcomes.

Protein supplementation of human milk for promoting growth in preterm infants

BACKGROUND

Preterm infants require high protein intake to achieve adequate growth and development. Although breast milk feeding has many benefits for this population, the protein content is highly variable, and inadequate to support rapid infant growth. This is a 2018 update of a Cochrane Review first published in 1999.

OBJECTIVES

To determine whether protein-supplemented human milk compared with unsupplemented human milk, fed to preterm infants, improves growth, body composition, cardio-metabolic, and neurodevelopmental outcomes, without significant adverse effects.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search CENTRAL, MEDLINE via PubMed, Embase, and CINAHL (February 2018). We also searched clinical trials databases, conference proceedings and the reference lists of retrieved articles for randomised controlled trials (RCT) and quasi-randomised trials.

SELECTION CRITERIA

Published and unpublished RCTs were eligible if they used random or quasi-random methods to allocate hospitalised preterm infants who were being fed human milk, to additional protein supplementation or no supplementation.

DATA COLLECTION AND ANALYSIS

Two review authors independently abstracted data, assessed risk of bias and the quality of evidence at the outcome level, using GRADE methodology. We performed meta-analyses, using risk ratio (RR) for dichotomous data, and mean difference (MD) for continuous data, with their respective 95% confidence intervals (CIs). We used a fixed-effect model and had planned to explore potential causes of heterogeneity via subgroup or sensitivity analyses.

MAIN RESULTS

We included six RCTs, involving 204 preterm infants. Low-quality evidence showed that protein supplementation of human milk increased in-hospital rates of growth in weight (MD 3.82 g/kg/day, 95% CI 2.94 to 4.7; five RCTs, 101 infants; I² = 73%), length (MD 0.12 cm/wk, 95% CI 0.07 to 0.17; four RCTs, 68 infants; I² = 89%), and head circumference (MD 0.06 cm/wk, 95% CI 0.01 to 0.12; four RCTs, 68 infants; I² = 84%). There was no evidence of a clear difference in rate of growth of skin fold thickness between the supplemented and unsupplemented groups (triceps MD 0.06 mm/wk, 95% CI -0.09 to 0.21; one RCT, 20 infants; or subscapular MD 0.00 mm/wk, 95% CI -0.17 to 0.17; one RCT, 20 infants). Protein supplementation led to longer hospital stays (MD 18.5 days, 95% CI 4.39 to 32.61; one RCT, 20 infants; very low-quality evidence), and higher blood urea nitrogen concentrations compared to the unsupplemented group (MD 0.95 mmol/L, 95% CI 0.81 to 1.09; four RCTs, 81 infants; I² = 56%). Very low-quality evidence did not show that protein supplementation clearly increased the risk of feeding intolerance (RR 2.70, 95% CI 0.13 to 58.24; one RCT, 17 infants), or necrotizing enterocolitis (RR 1.11, 95% CI 0.07 to 17.12; one RCT, 76 infants), or clearly altered serum albumin concentrations (MD 2.5 g/L, 95% CI -5.66 to 10.66; one RCT, 11 infants), compared with the unsupplemented groups. No data were available about the effects of protein supplementation on long-term growth, body mass index, body composition, neurodevelopmental, or cardio-metabolic outcomes.

AUTHORS' CONCLUSIONS

Low-quality evidence showed that protein supplementation of human milk, fed to preterm infants, increased short-term growth. However, the small sample sizes, low precision, and very low-quality evidence regarding duration of hospital stay, feeding intolerance, and necrotising enterocolitis precluded any conclusions about these outcomes. There were no data on outcomes after hospital discharge. Our findings may not be generalisable to low-resource settings, as none of the included studies were conducted in these settings.Since protein supplementation of human milk is now usually done as a component of multi-nutrient fortifiers, future studies should compare different amounts of protein in multi-component fortifiers, and be designed to determine the effects on duration of hospital stay and safety, as well as on long-term growth, body composition, cardio-metabolic, and neurodevelopmental outcomes.

Cow milk protein allergy presenting as feeding intolerance and eosinophilia: case reports of three preterm neonates

Three preterm infants with cow milk protein allergy (CMPA) presented with feeding intolerance, sepsis-like episodes and persistent moderate-to-severe eosinophilia. After eliminating cow milk, the clinical symptoms improved significantly. CMPA can cause common manifestations in sick preterm infants such as feeding intolerance and eosinophilia.

Growth and Tolerance of Preterm Infants Fed a New Extensively Hydrolyzed Liquid Human Milk Fortifier

OBJECTIVES

This study was a comparison of growth and tolerance in premature infants fed either standard powdered human milk fortifier (HMF) or a newly formulated concentrated liquid that contained extensively hydrolyzed protein.

METHODS

This was an unblinded randomized controlled multicenter noninferiority study on preterm infants receiving human milk (HM) supplemented with 2 randomly assigned HMFs, either concentrated liquid HMF containing extensively hydrolyzed protein (LE-HMF) or a powdered intact protein HMF (PI-HMF) as the control. The study population consisted of preterm infants ≤33 weeks who were enterally fed HM. Infants were studied from the first day of HM fortification until day 29 or hospital discharge, whichever came first.

RESULTS

A total of 147 preterm infants were enrolled. Noninferiority was observed in weight gain reported in the intent-to-treat (ITT) analysis was 18.2 and 17.5 g · kg(-1) · day(-1) for the LE-HMF and PI-HMF groups, respectively. In an a priori defined subgroup of strict protocol followers (n = 75), the infants fed LE-HMF achieved greater weight over time than those fed PI-HMF (P = 0.036). The LE-HMF group achieved greater linear growth over time compared to the PI-HMF (P = 0.029). The protein intake from fortified HM was significantly higher in the LE-HMF group compared with the PI-HMF group (3.9 vs 3.3 g · kg(-1) · day(-1), P < 0.0001). Both fortifiers were well tolerated with no significant differences in overall morbidity.

CONCLUSIONS

Both fortifiers showed excellent weight gain (grams per kilograms per day), tolerance, and low incidence of morbidity outcomes with the infants who were strict protocol followers fed LE-HMF having improved growth during the study. These data point to the safety and suitability of this new concentrated liquid HMF (LE-HMF) in preterm infants. Growth with this fortifier closely matches the recent recommendations for a weight gain of >18 g · kg(-1) · day(-1).

Cow's Milk Allergy in Preterm Infant with Bronchopulmonary Dysplasia

Cow's milk allergy is frequent in the first year of life. The symptoms may start during the first weeks of life, and may be cutaneous (50-60%), gastrointestinal (50-60%) or respiratory (20-30%), often involving more than one organ system. In this report, we describe a case of cow's milk allergy in a preterm infant in whom rectal bleeding and respiratory symptoms resolved with the introduction of an extensively hydrolyzed formula. Occurrence of the respiratory symptoms of this disorder in a preterm infant with bronchopulmonary dysplasia may cause re-hospitalization after discharge.

Retrospective multicenter survey on food-related symptoms suggestive of cow's milk allergy in NICU neonates

BACKGROUND

Cow's milk allergy (CMA) is one of the causes of gastrointestinal symptoms in neonates. A relationship between non-immunoglobulin (Ig) E mediated allergic reactions and CMA in early infancy has been proposed, but the clinical features and pathogenesis have not been established. The objective of this study is to determine the clinical characteristics of the neonates found in the earlier study to have food-related symptoms that suggested CMA.

METHODS

A second questionnaire was sent to 53 NICUs, as a follow-up to the earlier study, to collect information on the background, onset age, clinical features, and results of clinical examinations.

RESULTS

The median birth weight was 2614g and the median gestational age was 36.9 weeks. Symptoms developed within 6 days after birth in 40% of cases. Gastrointestinal symptoms were seen in 90% of cases and were mainly vomiting, bloody stool and abdominal distention. A specific IgE test, a lymphocyte stimulation test, and a fecal eosinophil test were conducted in 88%, 23% and 55% of cases, respectively, and the positive rates were 30%, 84%, and 75%, respectively. An oral food challenge (OFC) test was performed in 26% for confirmation of the diagnosis.

CONCLUSIONS

We confirmed that the clinical manifestations of food-related symptoms suggestive of CMA in neonates were distinctly different from those of common immediate type food allergy and were largely affected by underlying factors such as prematurity and gastroenterological surgery. Further OFC-based prospective accumulation of cases of CMA in neonates will be particularly important to reveal the full clinical features of this disease.

Myth: gastroesophageal reflux is a pathological entity in the preterm infant

There is concern about possible consequences of gastroesophageal reflux (GER) in preterm infants. GER is perceived to be a frequent condition in these infants, often causing an exhaustive investigation and expensive therapy. We review current evidence for and against an association between GER and apnea, failure to thrive, wheezing and respiratory diseases. Although there are some limitations to the methodologies currently used for detecting GER, there is clearly a lack of unequivocal evidence supporting a causal relationship between GER and its assumed consequences, particularly in preterm infants. Despite physiologic data that stimulation of laryngeal efferents by GER may induce apnea, there is little evidence for a causal relationship between GER and apnea. Studies on preterm infants with failure to thrive have also not demonstrated an association between the latter and GER in most cases, and there is equally little evidence for a casual relationship with respiratory problems. Therefore, we believe that GER in preterm infants is only rarely associated with serious consequences and existing evidence does not support the widespread use of anti-reflux medications for treatment of these signs in this age group. An improvement of methods to identify the few preterm infants at risk for developing serious consequences of GER is urgently needed.

Regurgitation in healthy and non healthy infants

Uncomplicate regurgitation in otherwise healthy infants is not a disease. It consists of milk flow from mouth during or after feeding. Common causes include overfeeding, air swallowed during feeding, crying or coughing; physical exam is normal and weight gain is adequate. History and physical exam are diagnostic, and conservative therapy is recommended. Pathologic gastroesophageal reflux or gastroesophageal reflux disease refers to infants with regurgitation and vomiting associated with poor weight gain, respiratory symptoms, esophagitis. Reflux episodes occur most often during transient relaxations of the lower esophageal sphincter unaccompanied by swallowing, which permit gastric content to flow into the esophagus. A minor proportion of reflux episodes occurs when the lower esophageal sphincter fails to increase pressure during a sudden increase in intraabdominal pressure or when lower esophageal sphincter resting pressure is chronically reduced. Alterations in several protective mechanisms allow physiologic reflux to become gastroesophageal reflux disease; diagnostic approach is both clinical and instrumental: radiological series are useful to exclude anatomic abnormalities; pH-testing evaluates the quantity, frequency and duration of the acid reflux episodes; endoscopy and biopsy are performed in the case of esophagitis. Therapy with H2 receptor antagonists and proton pump inhibitors are suggested.

Management of neonatal cow's milk allergy in high-risk neonates

BACKGROUND

We conducted a multicenter clinical survey to clarify the current attitudes to diagnosis or treatment of neonatal milk allergy (NMA) in institutions providing medical care for high-risk neonates in Japan.

METHODS

Questionnaires were distributed to 263 institutions that provide medical care for high-risk infants. Information was requested on the number of hospitalized neonates between January 2004 and December 2005, the number of neonates diagnosed with milk allergy, frequent clinical symptoms, and clinical tests performed routinely when NMA was suspected.

RESULTS

Responses were received from 145 institutions (55.1%). Of 69 796 hospitalized neonates, a diagnosis of cow's milk allergy was made in 0.21%. The incidence in infants with birthweight <1000 g was 0.35%. Gastrointestinal symptoms were identified as the most frequent symptoms that suggested NMA by 80% of institutions. A challenge test in each suspected case was performed in only 15% of institutions, even though it was considered to be the most significant test for diagnosis. Most institutions considered a specific immunoglobulin E test in cases of suspected NMA, but only one-third agreed on its diagnostic significance. A lymphocyte stimulation test was performed in only 5.5% of institutions.

CONCLUSIONS

This study is the first to show the incidence of NMA in institutions providing medical care for high-risk neonates in Japan. Current clinical tests may be insufficient for diagnosis of NMA in which non-immunoglobulin-E-mediated delayed allergic reactions are involved. Therefore, awareness of the clinical features of this disorder is required among neonatologists and allergists.

The efficacy of amino acid-based formulas in relieving the symptoms of cow's milk allergy: a systematic review

The aim of this systematic review was to evaluate the efficacy of amino acid-based formulas (AAF) in patients with cow's milk allergy (CMA). Studies were identified using electronic databases and bibliography searches. Subjects eligible for inclusion were patients of any age with CMA or symptoms suggestive of it. Comparisons of interest were AAF vs. extensively hydrolysed formula (eHF), AAF vs. soy-based formula (SF) and AAF vs. cow's milk or cow's milk-based formula. Outcomes of interest were gastrointestinal (GI), dermatological, respiratory and behavioural symptoms as well as growth. A total of 20 studies [three head-to-head randomized controlled trials (RCTs), three cross-over challenge RCTs, seven clinical trials (CTs) and seven case reports (CRs)] were included in the review. In infants with confirmed or suspected CMA, the use of an AAF was shown to be safe and efficacious. Findings from RCT comparisons of AAF with eHF showed that both formulas are equally efficacious at relieving the symptoms of CMA in confirmed or suspected cases. However, infants in specific subgroups (e.g. non-IgE mediated food-induced gastro-enterocolitis-proctitis syndromes with failure to thrive, severe atopic eczema, or with symptoms during exclusive breastfeeding) were more likely overall to benefit from AAF, as intolerance to eHF may occur. In such cases, symptoms persisting despite eHF feeding usually remit on AAF, and catch-up growth may be seen. Meta-analysis of the findings was not possible due to lack of homogenous reporting of outcomes in the original trials. This systematic review shows clinical benefit from use of AAF in both symptoms and growth in infants and children with CMA who fail to tolerate eHF. Further studies are required to determine the relative medical or economic value of initial treatment with AAF in infants at high risk of eHF intolerance.

A new model for studying eosinophil migration across cultured intestinal epithelial monolayers

OBJECTIVE

Eosinophils play an important role in some gastrointestinal inflammatory conditions. Stimulated eosinophils migrate across the vascular endothelial wall and into the intestinal epithelium where by-products such as proteases may contribute to intestinal epithelial damage. Little is known about the epithelial migration of the eosinophils in the gut. The lack of data is attributable in part to the scarcity of human eosinophils for studies. HL-60-differentiated eosinophils present a means to perform studies on eosinophil function and chemotaxis. HL-60 clone 15 can be induced to differentiate into cells closely resembling human eosinophils. The authors describe a novel model for studying eosinophil migration across the intestinal epithelium.

METHODS

Fluorescent-labeled HL-60 eosinophils were incubated for 150 minutes on the basolateral surface of confluent and inverted T-84 monolayers separated by fluoroblock insert membranes. Chemotactic gradients of n-formyl methionyl leucyl phenylalanine (fMLP), eotaxin, and platelet aggregating factor (PAF) were used in variable concentrations. Changes in transepithelial electrical resistance (TEER) were compared with baseline values.

RESULTS

Differentiated HL-60 eosinophils undergo migration in response to fMLP, PAF, and eotaxin. Migration is associated with a drop in TEER.

CONCLUSION

In this model, HL-60-differentiated eosinophils migrate in response to stimulants chemotactic for human eosinophils. The transepithelial migration of eosinophils is associated with epithelial barrier dysfunction, which may contribute to the development of disease.

Gastroesophageal reflux: a critical review of its role in preterm infants

There is widespread concern about gastroesophageal reflux (GER) in preterm infants. This article reviews the evidence for this concern. GER is common in infants, which is related to their large fluid intake (corresponding to 14 L/day in an adult) and supine body position, resulting in the gastroesophageal junction's being constantly "under water." pH monitoring, the standard for reflux detection, is of limited use in preterm infants whose gastric pH is >4 for 90% of the time. New methods such as the multiple intraluminal impedance technique and micromanometric catheters may be promising alternatives but require careful evaluation before applying them to clinical practice. A critical review of the evidence for potential sequelae of GER in preterm infants shows that 1) apnea is unrelated to GER in most infants, 2) failure to thrive practically does not occur with GER, and 3) a relationship between GER and chronic airway problems has not yet been confirmed in preterm infants. Thus, there is currently insufficient evidence to justify the apparently widespread practice of treating GER in infants with symptoms such as recurrent apnea or regurgitation or of prolonging their hospital stay, unless there is unequivocal evidence of complications, eg, recurrent aspiration or cyanosis during vomiting. Objective criteria that help to identify those presumably few infants who do require treatment for GER disease are urgently needed.

Gastroduodenal disorders in children

The North American Society for Pediatric Gastroenterology and Nutrition published guidelines for the evaluation of children suspected of being infected with Helicobacter pylori. The stool antigen test for H. pylori, which was recently commercialized in the United States, was evaluated in two high-risk pediatric populations. The results are encouraging but should be interpreted with caution. A number of studies suggest that delayed gastric emptying may accompany a variety of disorders, or may be a cause of vomiting. The outcome of children with dyspeptic symptoms is described, and the results will be helpful in reassuring anxious parents. Studies examining the development of H, K-adenosine triphosphatase in infants and the role of enteric glial cells in infantile hypertrophic pyloric stenosis are discussed. A study of neonates with allergic gastroenteropathy suggests that this disorder may be more common in this age group than generally thought.

Gastrointestinal food allergies: do they exist?

Gastrointestinal (GI) symptoms are often attributed to adverse reactions to foods (ARF), but it is not always clear whether such reactions are caused by food allergy. A reaction to food proteins that is mediated by immunologic events is referred to as food allergy or food hypersensitivity. One of the most common types of food allergy is the IgE-mediated immediate hypersensitivity reaction to foods, which can give rise to dermatologic and respiratory tract symptoms in addition to GI complaints. Other GI forms of food allergy include food protein-induced enterocolitis or gastroenteropathy, celiac disease, and some cases of eosinophilic gastroenteritis. Because most patients complaining of adverse reactions to food have non-immune mechanisms for their complaints, it is important to distinguish the various types of ARF, as their management may differ substantially. Recent advances in the field of food allergy provide opportunities to improve diagnostic methods and develop new modalities for management that will complement the current practice of allergen avoidance.