Manifestations of Cow's-Milk Protein Intolerance in Preterm Infants

Food-Protein-Induced Proctocolitis in Pre-Term Newborns with Bloody Stools in a Neonatal Intensive Care Unit

The bloody stools of newborns may be a clue for several clinical entities of varying severity, ranging from idiopathic neonatal transient colitis to food-protein-induced allergic proctocolitis (FPIAP) or necrotizing enterocolitis (NEC). Distinguishing among them at an early stage is challenging but crucial, as the treatments and prognoses are different. We conducted a monocentric retrospective study including all pre-term infants with bloody stools admitted to the Neonatal Intensive Care Unit (NICU) of the Vittore Buzzi Children's Hospital (Milan) from December 2022 to May 2024. Patients diagnosed with NEC exhibited significantly lower eosinophil counts and higher procalcitonin levels than both patients with FPIAP and patients with idiopathic neonatal transient colitis, as well as a statistically significant increase in pathological features from abdomen ultrasounds and abdominal X-rays. In contrast, no lab markers or imaging techniques have been demonstrated to be useful in distinguishing between idiopathic neonatal transient colitis and FPIAP. Thus, after excluding a diagnosis of NEC, the only way to confirm FPIAP is through the oral food challenge, which can be performed in premature newborns presenting with bloody stools who are otherwise healthy and under medical supervision, in order to identify infants who may benefit from a cow's-milk-free diet.

[Expert consensus on enteral nutrition management for preterm infants in special situations (2024)]

Establishing enteral nutrition after the birth of preterm infants presents numerous challenges, particularly for those in special situations. Various disease factors and medical interventions impede the establishment of enteral feeding, leading to conflicts and controversies regarding feeding goals, feeding methods, and the challenges and solutions faced by these infants. A critical issue for clinical physicians is how to safely and promptly establish enteral nutrition to achieve full enteral feeding as quickly as possible. The consensus formulation working group, based on both domestic and overseas research, adopted the Grading of Recommendations Assessment, Development and Evaluation, and formed an expert consensus on enteral nutrition management for preterm infants in special situations. This consensus provides 14 recommendations for 9 common special situations, aiming to offer guidance on enteral nutrition management for preterm infants to improve their short and long-term outcomes. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 665-676.

Exploring the links between necrotizing enterocolitis and cow's milk protein allergy in preterm infants: a narrative review

A broad range of allergic disorders and intolerance are associated with cow's milk protein in the infant diet. Allergy and intolerance to cow's milk proteins are commonly recognized in the healthy term infant, and the prevalence cow's milk protein intolerance (CMPI) varies widely but 5 challenge confirmed studies free from selection bias ranged from 1.9%-4.9%. These disorders are classified by the presence of IgE, non-IgE or T-cell-mediated signaling. Additionally, the severity of these adverse food reactions can range from mild gastrointestinal symptoms to severe sepsis-like episodes, as in the case of food protein-induced enterocolitis syndrome (FPIES). Food protein-induced intolerance in the healthy young infant lies in stark contrast to enterocolitis that typically occurs in the preterm neonate. Necrotizing enterocolitis (NEC) is a distinct progressive disease process, usually characterized by a high mortality rate, with a risk of death from 30% to 50%. While its exact etiology is unclear, its main triggers include formula (cow's milk protein), hypoxia, perfusion-related issues, and unregulated inflammation in the premature intestine. The distinction between NEC and cow's milk protein intolerance is difficult to discern in some cases. In the late preterm population, infants with colitis can have both NEC and cow's milk intolerance on the differential. In infants with multiple episodes of mild NEC, cow's milk protein intolerance may be the underlying diagnosis. In this review, we compare the pathophysiological characteristics, diagnosis and treatment of disorders of cow's milk protein intolerance with the entity of preterm NEC. This review highlights similarities in both entities and may inspire future cross-disciplinary research.

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.

Complementary food introduction practices in infants with intestinal failure

BACKGROUND

Oral intake in infants with intestinal failure (IF) may be limited due to intolerance or feeding difficulties. Guidelines for the introduction of semisolid or solid complementary foods (CFs) to infants with IF do not exist. CF intake and caloric contribution from CF is difficult to assess due to malabsorption and incomplete recording. The aim of this study was to identify institutional approaches to introducing CF to infants with IF.

METHODS

The American Society for Parenteral and Enteral Nutriton (ASPEN) Pediatric Intestinal Failure Section Registered Dietitian/Nutritionist (RDN) working group designed a 10-question online cloud-based survey to assess group member practice related to the introduction of CF to infants with IF.

RESULTS

Twenty-six surveys were completed. Thirteen (50%) RDNs recommend introduction of CF between 4 and 6 months of age. Nineteen (76%) recommend adding pureed foods to gastrostomy tube feedings. Seventeen (65%) follow standard infant feeding practice guidelines with half citing the American Academy of Pediatrics. Approximately half (44%) recommend introducing vegetables first and the majority (80%) recommend delaying the introduction of fruits. The vast majority (92%) recommend specific foods to minimize stool output including green beans, bananas, infant cereals, and meats/protein.

CONCLUSION

Institutional practices related to the introduction of CF to infants with IF vary. Similarities with first food choice and foods to avoid were observed. Evidenced-based practice guidelines for the introduction of CF to infants with IF need to be established to determine best practices for reducing stool output, encouraging weaning from parenteral nutrition, and achieving enteral autonomy.

Multi-strain probiotics for extremely preterm infants: a randomized controlled trial

BACKGROUND

Effects of probiotics on intestinal microbiota and feeding tolerance remain unclear in extremely low-birth-weight (ELBW) infants.

METHODS

ELBW infants were randomly assigned to receive probiotics or no intervention. Stool samples were collected prior to, 2 and 4 weeks after initiation, and 2 weeks after probiotics cessation for infants in the probiotics group, and at matched postnatal age time points for infants in the control group.

RESULTS

Of the 102 infants assessed for eligibility, sixty-two were included. Infants who received probiotics reached full enteral feeds sooner (Mean difference (MD) -1.8; 95% CI:-3.7 to -0.01 day), had a tendency toward lower incidence of hematochezia before hospital discharge (22.6% vs 3.2%; P = 0.053), and were less likely to require extensively hydrolyzed- or amino acids-based formulas to alleviate signs of cow's milk protein intolerance in the first 6 months of life (19.4% vs 51.6%; P = 0.008). Infants on probiotics were more likely to receive wide-spectrum antibiotics (64.5% vs 32.2%; P = 0.01). Multi-strain probiotics resulted in significant increase in fecal Bifidobacterium (P < 0.001) and Lactobacillus (P = 0.005), and marked reduction in fecal candida abundance (P = 0.04).

CONCLUSION

Probiotics sustained intestinal Bifidobacterium and reduced time to achieve full enteral feeds in extremely preterm infants. Probiotics might improve tolerance for cow's milk protein supplements.

CLINICAL TRIAL REGISTRATION

This trial has been registered at www.

CLINICALTRIALS

gov (identifier NCT03422562).

IMPACT

Probiotics may help extremely preterm infants achieve full enteral feeds sooner. Probiotics may improve tolerance for cow's milk protein supplements. Multi-strain probiotics can sustain intestinal Bifidobacterium and Lactobacillus until hospital discharge.

Effect of Maternal Diet on Any Necrotizing Enterocolitis in Neonates: A Randomized Double-Blind Study

Background: The etiology of necrotizing enterocolitis (NEC) is controversially discussed. One of the most recently proposed causes of NEC is an allergy to cow's milk protein. This study was designed to evaluate the effect of a maternal diet without bovine protein on the incidence of any NEC in very low birth weight (VLBW) infants. Materials and Methods: A pilot randomized controlled clinical trial was performed at Akbarabadi Hospital, Tehran, Iran, from December 2019 to July 2020, in women with VLBW infants. One hundred twenty mothers with VLBW neonates were randomly assigned to the intervention or the control group (60 in each). In the intervention group, mothers were given a dairy-free diet during the first 14 days after the newborn's onset of feeding. No special diet was given to the control group. The primary outcome of the study was the rate of any NEC in neonates, which was compared between groups. Any NEC was defined as Bell stage I or greater. Results: The minimum and maximum gestational ages were 26 and 33 weeks, respectively. The minimum birth weight of neonates was 700 g. The two groups did not differ significantly in terms of demographic and preinterventional clinical characteristics. Any NEC was reported in 0% and 10% (5/52) of neonates in the intervention and control groups, respectively; the difference was statistically significant (p = 0.028). The NEC symptoms began ∼34 days after birth. Four cases of NEC were classified as Bell stage I, and one was classified as Bell stage II. No statistical association was registered between sex, gestational age, birth weight, and the onset of feeding with the incidence of any NEC. Conclusion: The use of a cow's milk protein-free diet in mothers and exclusive breastfeeding in preterm VLBW infants may reduce the incidence of NEC. We recommend further studies with larger sample sizes in a multicenter setting. The study was registered at the Iranian Registry of Clinical Trials (IRCT20200415047086N1).

Clinical Observation of Extensively Hydrolysis Protein Formula With Feeding Intolerance in Preterm Infants

Objective

To investigate whether feeding extensively hydrolysis protein formula during the NICU hospitalization was more beneficial for preterm infants with a gestational age (GA) ≤34 weeks when breastfeeding was not possible.

Methods

In total, 587 preterm infants were randomly divided into two groups: observation groups fed with extensively hydrolyzed formula (EHF) milk and control groups fed with standard preterm formula (SPF) milk until discharge from the neonatal intensive care unit (NICU). The incidence of complications during hospitalization was recorded in both groups. Then, two groups were uniformly fed with 0-to-6-month infant formula milk and followed-up for 6 months after discharge.

Results

The final study included 370 premature infants, including 185 babies in the observation group and 185 in the control group. In contrast to the SPF, feeding EHF among preterm infants of GA <34 weeks during NICU hospitalization significantly reduced the incidence of feeding intolerance (FI) (14.1 vs. 30.3%, p < 0.01). The incidence of necrotizing enterocolitis (NEC) was significantly reduced in the observation group (2.2 vs. 6.5%, p < 0.05), but there was no significant difference in the incidence of other related complications. At discharge, there was no difference in total serum protein (46.6 vs. 46.4 g/L), albumin (33.5 vs. 34.2 g/L), and calcium (2.37 vs. 2.35 mmol/L), but the serum phosphorus concentrations associated with skeletal mineralization (2.10 vs. 2.22 mmol/L, p < 0.05) was significantly reduced and alkaline phosphatase significantly rose (254 vs. 220 IU/L, p < 0.05) in the observation group. No significant difference was found in the growth rates of body weight, head circumference, or body length, either during the NICU hospitalization or during the 6-month follow-up after discharge (p > 0.05).

Conclusions

Feeding premature infants of GA ≤34 weeks with EHF reduced the incidence of FI, but had no advantage in establishing whole intestinal nutrition, shortening parenteral nutrition (PN) time, or hospitalization time. It had little effect on physical growth or development during NICU hospitalization and within 6 months after discharge. However, it may increase the incidence of metabolic bone disease (MBD).

Malabsorption Syndromes and Food Intolerance

Feeding intolerance is ubiquitous in neonatal intensive care units with as many signs and symptoms as possible diagnoses. Optimizing nutrition is paramount in both preterm and term infants. Determining the cause of feeding intolerance and adjusting nutrition interventions is an important part of the daily care of newborns. This review discusses the role of malabsorption and food intolerance as possible causes of nutrition difficulties in the newborn.

Spontaneous intestinal perforation (SIP) will soon become the most common form of surgical bowel disease in the extremely low birth weight (ELBW) infant

Recent data have revealed declines in the prevalence rates of NEC over the last decade in premature infants. In contrast, SIP has either remained steady or risen during the same epoch. These trends are consistent with our knowledge of the clinical arena. The ability to discern SIP contamination within NEC datasets has slowly improved. Additionally, quality improvement efforts are being utilized to reduce NEC through stewardship of antibiotics, acid inhibitors, central lines and blood products, as well as optimization of human milk diets. These forces are moving us to a new era, where NEC will no longer be the dominant surgical intestinal disease of the extremely preterm neonate. Indeed, in the extremely low birth weight (ELBW) population, SIP may already be the most prevalent reason for abdominal surgery. In this perspective, the reader will find supporting data and references for these assertions as well as predictions for the future.

Feeding practices and the prevalence of cow's milk protein allergy in Irish preterm infants

BACKGROUND

The prevalence of cow's-milk protein allergy (CMPA) is between 2% and 3% and symptoms vary depending on underlying immune mechanism at play. Breast milk is the optimal nutrition for premature infants and breast milk fortifiers (BMF) are commonly used to optimise growth and nutrition. BMF are typically derived from cow's milk and, as such, preterm infants are exposed to cow's milk in the first weeks of life. Previously, preterm infants were suspected to have a higher risk of allergen development because of early antigen exposure and increased gut permeability. The primary aim of the present study was to evaluate the prevalence of CMPA among very preterm (<32 weeks) and/or very low birth weight (VLBW) infants. The secondary aim was to describe feeding practices, specifically the breastfeeding rates and specialist, non-standard formula use in this cohort over the first 6 months of life.

METHODS

This was a retrospective study performed in a large tertiary maternity hospital (8500 deliveries/year and 110 very preterm infants/year) in Dublin, Ireland over a 3-year period, 2017-2020. Infants born very preterm and/or VLBW who were followed in the outpatient clinic until 6 months corrected gestational age (CGA) were included. Hospital ethical approval was obtained.

RESULTS

One hundred and forty-four infants were included with a median birth weight of 1338 g. No infant had a diagnosis of CMPA when leaving the neonatal intensive care unit (NICU) but, by 6 months CGA, this increased to 1.4% (n = 2). Upon discharge from the NICU, 88 infants (61%) were receiving at least some breast milk, decreasing to 13 (9.1%) at 6 months CGA. Those who were receiving exclusive breast milk at discharge were significantly more likely to still be receiving any breast milk at three (p ≤ 0.001) and 6 months ( p ≤ 0.001) CGA compared to those combined feeding or exclusively formula feeding. At 6 months CGA, 18.9% (n = 27) were attending a dietician and 31.5% (n = 45) were using specialist, non-standard infant formula.

CONCLUSIONS

The prevalence of CMPA in this cohort was 1.4%, which is similar to the reported prevalence of CMPA in the general paediatric population. Infants who were discharged from NICU exclusively breastfeeding were more likely to be receiving any breast milk at outpatient follow-up. This highlights the importance of on going dietetic and lactation support in the outpatient setting for this vulnerable cohort.

Newborns with Bloody Stools-At the Crossroad between Efficient Management of Necrotizing Enterocolitis and Antibiotic Stewardship

The onset of bloody stools in neonates often results in antibiotic treatment for suspected necrotizing enterocolitis (NEC). Food protein-induced allergic proctocolitis (FPIAP) is an often-neglected differential diagnosis. We performed a retrospective analysis of antibiotic exposure at our tertiary center from 2011 to 2020 that included three time periods of differing antimicrobial stewardship goals. We compared these data with the conventional treatment guidelines (modified Bell's criteria). In our cohort of 102 neonates with bloody stools, the length of antibiotic exposure was significantly reduced from a median of 4 to 2 days. The proportion of treated neonates decreased from 100% to 55% without an increase in negative outcomes. There were 434 antibiotic days. Following a management strategy according to modified Bell's criteria would have led to at least 780 antibiotic days. The delayed initiation of antibiotic treatment was observed in 7 of 102 cases (6.9%). No proven NEC case was missed. Mortality was 3.9%. In conclusion, with FPIAP as a differential diagnosis of NEC, an observational management strategy in neonates with bloody stools that present in a good clinical condition seems to be justified. This may lead to a significant reduction of antibiotic exposure. Further prospective, randomized trials are needed to prove the safety of this observational approach.

Safety and efficacy of human milk-based fortifier in enterally fed preterm and/or low birthweight infants: a systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis of the efficacy and safety of fortification of human milk with human milk-based fortifier versus cow's milk-based fortifier for use in preterm and/or very low birthweight infants.

DESIGN

Randomised or quasi-randomised controlled trials comparing the effect of human milk fortification with human milk-based milk fortifier versus cow's milk-based fortifier in infants born <34 weeks' gestation and/or with birth weight <1500 g were identified by searching databases, clinical trial registries and reference lists until 5 November 2019. Two authors independently extracted data and assessed evidence quality. Meta-analyses were conducted using fixed or random effects models, as appropriate.

MAIN OUTCOME MEASURES

Necrotising enterocolitis (Bell's stage II or higher) and late-onset sepsis.

RESULTS

Of 863 unique records identified, 16 full-text trials were screened and 2 trials involving 334 infants were included. Primary outcome data were available for 332 infants. Use of human milk-based fortifier compared with cow's milk-based fortifier reduced the risk of necrotising enterocolitis (risk ratio 0.47, 95% CI 0.22 to 0.98). There was no clear evidence of an effect on late-onset sepsis or any other outcomes. The quality of evidence was low to very low due to imprecision and lack of blinding in one study.

CONCLUSIONS

Findings suggest that there is a reduction in the incidence of necrotising enterocolitis with human milk-based fortifiers compared with cow's milk-based fortifiers. The overall quality of evidence is low. Further appropriately powered trials are required before this intervention can be routinely recommended for preterm infants.

A Preterm Case of Cow's Milk Allergy Presenting with Recurrent Ascites Treated with Donor Breast Milk

We report a case of a preterm infant who developed cow’s milk allergy. This male infant presented with recurrent ascites and was successfully treated with donated breast milk. He was born at 24 weeks’ gestation with a birthweight of 506 g. From day 20, infant formula, soy protein-based formula, and casein-hydrolyzed formula were used due to insufficient maternal lactation. This resulted in abdominal distention, generalized edema, and recurrent ascites. We diagnosed him with cow’s milk allergy since these symptoms improved on exclusive breast milk feeding. No recurrence of symptoms occurred when donated breast milk was used in combination with the mother’s own milk. Ascites should be regarded as a clinical symptom of neonatal cow’s milk allergy. Donated breast milk may be effective in the treatment of the allergy if breastfeeding is not available.

Cow's Milk Protein Allergy in Term and Preterm Infants: Clinical Manifestations, Immunologic Pathophysiology, and Management Strategies

Cow's milk allergy is a common food allergy among infants. Symptoms of cow's milk allergy are wide-ranging and depend on the mechanism involved. There are immunoglobulin E (IgE)-mediated, non-IgE-mediated, and mixed mechanisms of food allergy. Symptoms of IgE-mediated cow's milk allergy may be mild or may progress to anaphylaxis, which can be life-threatening. Non-IgE-mediated allergy includes food protein-induced allergic proctocolitis (FPIAP), food protein-induced enterocolitis syndrome, food protein-induced enteropathy, and Heiner syndrome (pulmonary hemosiderosis). These diagnoses comprise about half of all cow's milk allergies. The most common manifestation of cow's milk allergy in infants is FPIAP. FPIAP is commonly seen in healthy, full-term infants who present with rectal bleeding and are otherwise well-appearing. This can occur in both formula-fed and exclusively breastfed infants. Food proteins secreted in maternal breast milk can contribute to the development of these symptoms. Maternal cow's milk elimination diet is often successful in helping resolve symptoms. A period of reintroduction of cow's milk resulting in re-emergence of symptoms in stable asymptomatic infants is an excellent diagnostic tool to confirm a cow's milk allergy. Preterm infants are susceptible to food allergy, as demonstrated from several case reports of necrotizing enterocolitis-like illnesses that responded clinically to cow's milk elimination. Further study is needed about food allergy in the preterm infant population.

Human Milk-Derived Fortifiers Compared with Bovine Milk-Derived Fortifiers in Preterm Infants: A Systematic Review and Meta-Analysis

This systematic review assessed outcomes after using human milk-derived fortifier (HMF) compared with bovine milk-derived fortifier (BMF) in preterm infants. Six randomized controlled trials (RCTs) were included. Meta-analysis using a random-effects model showed the following results: 1) lower risk of necrotizing enterocolitis (NEC; ≥Stage II) (RR: 0.38; 95% CI: 0.15, 0.95; P = 0.04, I2 = 9%; n = 334, 4 RCTs) and surgical NEC (RR: 0.13; 95% CI: 0.02, 0.67; P = 0.02, I2 = 0%; n = 209, 3 RCTs) in the HMF group; 2) no significant difference in mortality (RR: 0.40; 95% CI: 0.14, 1.15; P = 0.09, I2 = 0%; n = 334, 4 RCTs); 3) lower weight gain in the HMF group [mean difference (MD) = -1.08 g · kg-1 · d-1; 95% CI: -1.96, -0.21 g · kg-1 · d-1; P = 0.02, I2 = 0%; n = 241, 4 RCTs]; 4) no differences for length (MD = -0.11 cm/wk; 95% CI: -0.26, 0.04 cm/wk; P = 0.14, I2 = 68%) and head circumference (MD = -0.02 cm/wk; 95% CI: -0.08, 0.05 cm/wk; P = 0.59, I2 = 23%); and 5) no significant difference in late-onset sepsis (RR: 0.96; 95% CI: 0.56, 1.67; P = 0.90, I2 = 63%; n = 334, 4 RCTs). The beneficial effects of HMF for NEC were no longer significant in sensitivity analyses after excluding studies with high risk of bias. Quality of evidence as per Grading of Recommendations, Assessment, Development and Evaluation (GRADE) analysis was low to very low, and hence the confidence in these results is low. In summary, fortification of milk in preterm infants with HMF compared with BMF decreased the risk of NEC but was associated with lower weight gain. Given the low quality of evidence, adequately powered and well-designed RCTs without the influence of industry are required in this field.