Effects of different CMV-heat-inactivation-methods on growth factors in human breast milk

Postnatally acquired cytomegalovirus infection among preterm infants

PURPOSE OF REVIEW

Although there are multiple benefits of mother's own milk feeding for very-low birth weight, low gestation infants, those born to cytomegalovirus (CMV)-seropositive mothers are at risk for acquiring postnatal CMV infection. This review will describe the risk and consequences of postnatal CMV infection among very preterm infants.

RECENT FINDINGS

Postnatal CMV may manifest as clinically silent infection or as mild to severe and occasionally fatal disease. The risk of disease is balanced by the health benefits of human milk feeding to preterm infants. Postnatal CMV infection has been associated with increased risks of multiple preterm morbidities such as bronchopulmonary dysplasia, necrotizing enterocolitis and neurodevelopmental impairment, but current evidence is limited by the selection bias inherent to reporting in case series and retrospective cohort studies.

SUMMARY

Knowledge gaps exist regarding the risk-benefit balance of pasteurization to inactivate CMV in fresh breast milk, as well as the optimal dosing, duration and efficacy of treating infected infants with antiviral medications. Multicenter, prospective studies are urgently needed to accurately determine the true burden that postnatal CMV infection presents to very preterm infants. Such studies will inform the need for preventive strategies and treatment guidance.

A review on the safety of growth factors commonly used in cultivated meat production

Growth factors are commonly added to cell culture media in cellular agriculture to mimic the endogenous process of proliferation and differentiation of cells. Many of these growth factors are endogenous to humans and known to be present in the edible tissues and milk of food animals. However, there is little or no information on the use of growth factors intentionally added in food production before the advent of cultivated meat. Ten commonly used growth factors have been reviewed to include information on their mode of action, bioavailability, occurrence in food and food animals, endogenous levels in humans, as well as exposure and toxicological information drawn from relevant animal studies and human clinical trials with a focus on oral exposure. In addition, a comparison of homology of growth factors was done to compare the sequence homology of growth factors from humans and domestic animal species commonly consumed as food, such as bovine, porcine, and poultry. This information has been gathered as the starting point to determine the safety of use of growth factors in cultivated meat meant for human consumption. The change in levels of growth factors measured in human milk and bovine milk after pasteurization and high-temperature treatment is discussed to give an indication of how commercial food processing can affect the levels of growth factors in food. The concept of substantial equivalence is also discussed together with a conservative exposure estimation. More work on how to integrate in silico assessments into the routine safety assessment of growth factors is needed.

Associations between Bronchopulmonary Dysplasia, Insulin-like Growth Factor I and Nutrition

Insulin-like growth factor I (IGF-I) has been suggested as an important factor in the pathogenesis of bronchopulmonary dysplasia (BPD). In turn, nutrition has been associated with IGF-I levels and could be of importance in the pathogenesis of BPD. This study aimed to explore the association between nutrition, the IGF-I axis and the occurrence of BPD. Eighty-six preterm infants (44 male, mean gestational age: 29.0 weeks (standard deviation: 1.7 weeks)) were enrolled in an observational study. Serum IGF-I (µg/L) and insulin-like growth factor binding protein 3 (IGFBP-3; mg/L) were measured at birth and at 2, 4 and 6 weeks postnatal age. BPD was diagnosed at 36 weeks postmenstrual age. Twenty-nine infants were diagnosed with BPD. For every µg/L per week increase in IGF-I, the odds of BPD decreased (0.68, 95% CI 0.48-0.96, corrected for gestational age). The change in IGF-I in µg/L/week, gestational age in weeks and a week of predominant donor human milk feeding were associated with the occurrence of BPD in the multivariable analysis (respectively, OR 0.63 (0.43-0.92), OR 0.44 (0.26-0.76) and 7.6 (1.2-50.4)). IGFBP-3 was not associated with the occurrence of BPD in the multivariable analysis. In conclusion, a slow increase in IGF-I levels and a lower gestational age increase the odds of BPD. Donor human milk might increase the odds of BPD and should be further explored.

Prevention of human milk-acquired cytomegalovirus infection in very-low-birth-weight infants

BACKGROUND

The aim of the study was to determine the rate of cytomegalovirus virolactia in the human milk (HM) of mothers of VLBW infants, compare the CMV infection rates and the changes in CMV DNA viral load and nutrient profile among different HM preparation methods.

METHODS

A prospective randomized controlled study was performed in infants with gestational age < 32 weeks or birth-weight < 1500 g admitted to neonatal intensive care unit of Asan Medical Center and Haeundae Paik Hospital who were given mother's own milk. Enrolled infants were randomized into three groups according to the HM preparation methods: freezing-thawing (FT), FT + low-temperature Holder pasteurization (FT + LP), and FT + high-temperature short-term pasteurization (FT + HP). Urine CMV culture and PCR were obtained at birth and at 4, 8, and 12 weeks. HM CMV culture and PCR were obtained at birth and at 3, 6, 9, and 12 weeks. Changes in macronutrients in HM was obtained at 4 ~ 6 weeks.

RESULTS

Of 564 infants, 217 mothers (38.5%) produced CMV PCR positive milk. After exclusion, a total of 125 infants were randomized into the FT (n = 41), FT + LP (n = 42), and FT + HP (n = 42) groups, whose rate of HM-acquired CMV infection was 4.9% (n = 2), 9.5% (n = 4), and 2.4% (n = 1), respectively. Out of seven CMV infected infants, two infants fed with FT + LP HM developed CMV infection- associated symptoms. Ages at diagnoses were earlier (28.5 days after birth) and at younger post conceptional age (< 32 weeks) in comparison to infants with asymptomatic CMV infection. CMV DNA viral load significantly decreased after pasturizations, especially in FT + HP group.

CONCLUSIONS

HM-acquired symptomatic CMV infection rate is low and its impact on clinical course was not serious in our VLBW infants. However, evidences showing poor neurodevelopmental outcome in later life, we need to generate a guideline to protect VLBW infant form HM transmitted CMV infection. Based on our small sized study, we did not find any superiority in pasteurizing HM with frequently used LP in comparison to frozen or HP HM. More research is needed to determine the method and duration of pasteurization to reduce the HM-acquired CMV infection.

Human Milk Growth Factors and Their Role in NEC Prevention: A Narrative Review

Growing evidence demonstrates human milk's protective effect against necrotizing enterocolitis (NEC). Human milk derives these properties from biologically active compounds that influence intestinal growth, barrier function, microvascular development, and immunological maturation. Among these protective compounds are growth factors that are secreted into milk with relatively high concentrations during the early postnatal period, when newborns are most susceptible to NEC. This paper reviews the current knowledge on human milk growth factors and their mechanisms of action relevant to NEC prevention. It will also discuss the stability of these growth factors with human milk pasteurization and their potential for use as supplements to infant formulas with the goal of preventing NEC.

Optimizing Early Neonatal Nutrition and Dietary Pattern in Premature Infants

Providing adequate amounts of all essential macro- and micronutrients to preterm infants during the period of extraordinarily rapid growth from 24 to 34 weeks' postmenstrual age to achieve growth as in utero is challenging yet important, since early growth restriction and suboptimal neonatal nutrition have been identified as risk factors for adverse long-term development. Along with now well-established early parenteral nutrition, this review emphasizes enteral nutrition, which should be started early and rapidly increased. To minimize the side effects of parenteral nutrition and improve outcomes, early full enteral nutrition based on expressed mothers' own milk is an important goal. Although neonatal nutrition has improved in recent decades, existing knowledge about, for example, the optimal composition and duration of parenteral nutrition, practical aspects of the transition to full enteral nutrition or the need for breast milk fortification is limited and intensively discussed. Therefore, further prospective studies on various aspects of preterm infant feeding are needed, especially with regard to the effects on long-term outcomes. This narrative review will summarize currently available and still missing evidence regarding optimal preterm infant nutrition, with emphasis on enteral nutrition and early postnatal growth, and deduce a practical approach.

Human Cytomegalovirus Genome Diversity in Longitudinally Collected Breast Milk Samples

Reactivation and shedding of human cytomegalovirus (HCMV) in breast milk during lactation is highly frequent in HCMV-seropositive mothers. This represents a key transmission route for postnatal HCMV infection and can lead to severe disease in preterm neonates. Little is known about HCMV strain composition or longitudinal intrahost viral population dynamics in breast milk from immunocompetent women. We performed HCMV-specific target enrichment and high-throughput sequencing of 38 breast milk samples obtained in Germany between days 10 and 60 postpartum from 15 mothers with HCMV DNA lactia, and assembled HCMV consensus sequences de novo. The genotype distribution and number of HCMV strains present in each sample were determined by quantifying genotype-specific sequence motifs in 12 hypervariable viral genes, revealing a wide range of genotypes (82/109) for these genes in the cohort and a unique, longitudinally stable strain composition in each mother. Reactivation of up to three distinct HCMV strains was detected in 8/15 of mothers, indicating that a representative subset of the woman’s HCMV reservoir might be locally reactivated early during lactation. As described previously, nucleotide diversity of samples with multiple strains was much higher than that of samples with single strains. Breast milk as a main source of postnatal mother-to-infant transmission may serve as a repository for viral diversity and thus play an essential role in the natural epidemiology of HCMV.

Literature Review and an Italian Hospital Experience about Post-Natal CMV Infection Acquired by Breast-Feeding in Very Low and/or Extremely Low Birth Weight Infants

Breastfeeding is recommended for all neonates due to a known variety of beneficial effects, but infants can be infected by cell-associated bacteria and viruses from breast milk, such as cytomegalovirus (CMV). The majority of CMV-seropositive breastfeeding women have a viral, self-restricted reactivation, can shed the virus in the milk for about 12 weeks after delivery, and can transmit the infection to their offspring. Post-natal CMV-infected term infants are mainly asymptomatic, while very low birth weight (VLBW, <1500 g) and extremely low birth weight (ELBW, <1000 g) infants may present with severe disease, short-term sequelae ranging from abnormalities in laboratory indexes to sepsis-like syndrome, and long-term sequelae such as developmental problems. Thus, the use of thermally treated maternal milk for VLBW/ELBW infants may be indicated to prevent/reduce the risk of CMV transmission. Different techniques, with varying efficacy in eradicating CMV and maintaining the activity of biological compounds in milk are available: long/short pasteurization, freeze-thawing, the use of microwaves, and ultraviolet-C irradiation. In our NICU, the use of maternal raw milk is always strongly recommended for term/preterm infants, but to reduce risk of CMV transmission, freeze-thawing mother's own milk is used in neonates with GA ≤ 30 weeks or/and weight ≤ 1000 g, usually regardless of serological maternal condition, as CMV screening is not routinely offered to pregnant women and the milk of seroimmune mothers is not evaluated for CMV reactivation, as its rate is similar to seroprevalence. Over the last 4 years, we had 10 VLBW/ELBW newborns in our NICU with late-onset sepsis and negative cultures. In these cases, the research of CMV DNA in neonatal urine or saliva, for the diagnosis of post-natal symptomatic infection (once congenital transmission has been excluded) may be useful and not invasive. The take-home message we would like to share is that acquired CMV infection should be considered in VLBW/ELBW infants breastfed by seropositive mothers and presenting severe symptoms-particularly sepsis with negative cultures. This could allow pediatricians to make better-quality diagnoses, perform supportive therapy, provide antiviral treatment if needed, or establish a "pre-emptive" therapy for these high-risk neonates.

High-Temperature Short-Time Preserves Human Milk's Bioactive Proteins and Their Function Better Than Pasteurization Techniques With Long Processing Times

Donor human milk is generally processed by holder pasteurization (HoP) at 62. 5°C for 30 min. This temperature-time combination is sufficient for eliminating pathogens in donor milk, but also negatively affects several bioactive milk components. Long heating up times may further affect the bioactive properties of pasteurized milk. High-Temperature-Short-Time (HTST), a treatment with shorter processing times (72°C for 15 sec), was investigated as a suitable alternative to HoP. In addition, pasteurization methods that follow the same temperature regime but with varying heating up times were compared. Human milk samples from four different donors were combined into one pool, which was then used to perform all analyses. The effects of these methods on the levels and functionality of immunoglobulin A, lactoferrin, lysozyme and bile salt-stimulated lipase, were evaluated with LC-MS/MS-based proteomics and activity assays, while the pasteurization efficacy was evaluated with an alkaline phosphatase test. HoP, a treatment with long processing times, times, caused the highest reduction in all proteins studied (reduced by 50-98%). Compounds such as lactoferrin and bile salt-stimulated lipase that are more sensitive to heat treatments were better retained with HTST, but their levels and functionality were still significantly lower than those of untreated donor milk (52 and 81% reduction of lactoferrin and bile salt-stimulated lipase activity, respectively). Our findings showed that a treatment with considerably shorter processing times, such as HTST, may reduce the thermal damage caused to the bioactive proteins compared to HoP, without affecting pasteurization efficacy. Since the vast majority of the donor human milk banks that are currently operating on a global level apply HoP to donor milk, our findings may provide relevant information for the optimization of donor milk processing.

Metabolomic Profile of Personalized Donor Human Milk

Human milk could be considered an active and complex mixture of beneficial bacteria and bioactive compounds. Since pasteurization drastically reduces the microbial content, we recently demonstrated that pasteurized donor human milk (DHM) could be inoculated with different percentages (10% and 30%) of mother's own milk (MOM) to restore the unique live microbiota, resulting in personalized milk (RM10 and RM30, respectively). Pasteurization affects not only the survival of the microbiota but also the concentration of proteins and metabolites, in this study, we performed a comparative metabolomic analysis of the RM10, RM30, MOM and DHM samples to evaluate the impact of microbial restoration on metabolite profiles, where metabolite profiles clustered into four well-defined groups. Comparative analyses of DHM and MOM metabolomes determined that over one thousand features were significantly different. In addition, significant changes in the metabolite concentrations were observed in MOM and RM30 samples after four hours of incubation, while the concentration of metabolites in DHM remained constant, indicating that these changes are related to the microbial expansion. In summary, our analyses indicate that the metabolite profiles of DHM are significantly different from that of MOM, and the profile of MOM may be partially restored in DHM through microbial expansion.

Impact of breast milk-acquired cytomegalovirus infection in premature infants: Pathogenesis, prevention, and clinical consequences?

Maternal-fetal transmission of cytomegalovirus (CMV) represents the most common infectious cause of long-term neurodevelopmental disability in children. Congenital CMV (cCMV) infection is associated with microcephaly, seizure disorders, cognitive disability, developmental delay, and sensorineural hearing loss (SNHL). Of these disabilities, SNHL is the most common, affecting approximately 10% of infants with cCMV. Although the sequelae of cCMV are well recognized, it is much less clear what long-term morbidities may occur in neonates that acquire post-natal CMV infection. Post-natal CMV (pCMV) infection is most commonly transmitted by breast-feeding, and in full-term infants is of little consequence. However, in preterm, very-low birthweight (VLBW) infants (<1500 g), pCMV can result in a severe sepsis-like syndrome, with wide-ranging end-organ disease manifestations. Although such short-term complications are well recognized among clinicians caring for premature infants, the long-term risks with respect to adverse neurodevelopmental outcomes remain controversial. In this review, we provide an overview of the clinical manifestations of breast milk-acquired pCMV infection. In particular, we summarize studies that have examined-sometimes with conflicting conclusions-the risks of long-term adverse neurodevelopmental outcome in VLBW infants that acquire pCMV from breast milk. We highlight proposed preventive strategies and antiviral interventions, and offer recommendations for high-priority areas for future basic science and clinical research.

Immunomodulatory Constituents of Human Donor Milk

Mother's own human milk is the best nutrition for infants, especially preterm very-low-birth-weight (VLBW) (≤1,500 g) infants, because of its immune-modulatory constituents that strengthen the infant's host defense, provide protection against infections, and decrease the risk of necrotizing enterocolitis (NEC). When mother's own milk is unavailable or insufficient, donor human milk is considered the best alternative, especially for preterm VLBW infants. However, to assure biological safety, donor milk must be pasteurized. This results in partial or complete inactivation of some of the immunomodulatory constituents of human milk, which confer host defense. This review summarizes the current evidence regarding the effects of pasteurization on the different immunological constituents of donor milk, and their clinical significance, especially in relation to prevention of NEC.

Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome

The objective of this study was to investigate the effects of heat treatment on colostral low-abundant proteins, IgG and IgA, insulin, and insulin-like growth factor I (IGF-I), as well as bacteria and somatic cells. First-milking colostrum samples >8 L and Brix % > 22.0 were harvested from 11 Holstein cows on a commercial dairy in New York State and split into 2 aliquots using single-use colostrum bags. One aliquot of each pair was cooled on ice immediately after harvest (raw, R; n = 11), and the other was heat-treated for 60 min at 60°C (heat, H; n = 11). All samples were analyzed for IgG and IgA via radial immunodiffusion assay and insulin and IGF-I concentrations by radioimmunoassay. Total bacterial counts and somatic cell counts (SCC) were determined using standard plate culture techniques and flow cytometry, respectively. Samples from a subset of 5 pairs (n = 10) were further analyzed by nano liquid chromatography-tandem mass spectroscopy, after ultracentrifugation at 100,000 × g for 60 min at 4°C to enrich the low-abundant protein whey fraction. Data were analyzed using either paired t-test or Wilcoxon signed-rank test or using an online software package to analyze proteomics data. Outcomes of proteomics analysis were fold change ≥1.5 between pairs, and paired t-tests with false discovery rate-adjusted P-value < 0.05. The median reduction of IgA concentrations was 8.5% (range: 0-38.0%) due to heat treatment, whereas IgG concentrations did not change due to treatment. Insulin concentrations decreased by a median of 22% (7-45%), and IGF-I decreased by 10% (0-18%) in H samples. Heat treatment was associated with a median reduction of SCC of 36% (0-90%) in paired samples, as well as a median reduction in total bacterial count of 93% (45-100%) in H versus R samples. Proteomics analysis identified a total of 328 unique proteins that were present in all 10 samples. Nine of the 25 proteins that decreased by at least 1.5-fold in H compared with R were identified as complement proteins. We conclude that heat treatment of colostrum is associated with a reduction in the concentration of bacterial counts and SCC, IgA, insulin, and IGF-I. In addition, proteomics analysis of colostral whey identified several complement components and other proteins that decreased in abundance due to heat treatment. Although IgG concentrations were unaffected and a reduction in bacterial counts was achieved, the change in several immunologically active proteins and growth factors may have biologically important effects on the developing immune system of the neonate fed heat-treated colostrum.

Short-term Pasteurization of Breast Milk to Prevent Postnatal Cytomegalovirus Transmission in Very Preterm Infants

BACKGROUND

Postnatally acquired cytomegalovirus (pCMV) infection through breast milk (BM) may cause severe illness and even death, yet BM is advantageous for preterm infants. Therefore, effective methods to prevent CMV transmission are needed.

METHODS

To assess the effectiveness of short-term pasteurization (62°C for 5 seconds) in preventing CMV transmission via BM in preterm infants. Design: Prospective interventional bicentric cohort study with infant enrollment between 6/2010 and 1/2012. A cohort from the Tuebingen neonatal intensive care unit (NICU) from 1995-1998 served as historical controls. Differences in CMV transmission were compared with reference to the cumulative time at risk for CMV transmission. Setting: Two German level-3 NICUs. Eighty-seven preterm infants of 69 CMV immunoglobulin G-positive mothers with birth weight <1500 g or gestational age <32 weeks and 83 historical controls were included. Intervention: BM samples were short-term pasteurized from postnatal day 4 to discharge. Primary endpoint: CMV status at discharge, evaluated by polymerase chain reaction and short-term microculture from urine.

RESULTS

Two of 87 (2.3%) study infants had a pCMV transmission. This compared to 17 of 83 (20.5%) controls. Total time under risk for infection was 9.6 years vs 10.0 years in controls, yielding an incidence of 0.21/year (95% confidence interval [CI], 0.03 to 0.75/year) vs 1.70/year (95% CI, 0.99 to 2.72/year), respectively. The risk ratio controls vs study infants was 8.3 (95% CI, 2.4 to 52.4) according to Cox proportional hazard model (P = .0003).

CONCLUSIONS

Short-term pasteurization significantly reduces the incidence of pCMV infection through BM in the NICU.

CLINICAL TRIALS REGISTRATION

NCT01178905.

Microwave treatment of breast milk for prevention of cytomegalovirus infection

BACKGROUND

Breast milk (BM) is the best nutrition for very preterm infants (VPI), except when provided by human cytomegalovirus (HCMV)-seropositive mothers. Given that VPI are at high risk of developing a sepsis-like syndrome or cholestasis, methods for prevention of HCMV infection via BM have been investigated. Although Holder pasteurization (HP) is the gold standard, HP needs special instruments. Microwave (MW) is available anywhere, therefore, we performed this study to determine whether MW can be used for HCMV prevention.

METHODS

Human cytomegalovirus Towne strain was added to formula, followed by heating procedure using HP or MW (at 500 W for 20, 30, 40, or 60 s). HFL-III cells were seeded in culture dishes. Aliquots of HCMV-milk samples after heating were inoculated onto susceptible cell monolayers. The number of plaques was counted to determine the viral titer. The determination of HCMV-DNA copies was also performed.

RESULTS

Addition of HCMV for a viral load of 5.0 × 10³ plaque-forming units (p.f.u.)/mL achieved 772 p.f.u./mL at baseline, with a decrease to 257 p.f.u./mL after MW radiation for 20 s. No plaque was detected after HP or MW for 30, 40, and 60 s. The temperature of the breast milk reached 60°C after MW radiation for 40 s. The number of HCMV-DNA copies did not change with MW.

CONCLUSIONS

Microwave at 500 W for 40 s can be used as a prevention strategy for HCMV transmission. Further research including the loss of bioactive properties in BM is required prior to clinical application.

New short-term heat inactivation method of cytomegalovirus (CMV) in breast milk: impact on CMV inactivation, CMV antibodies and enzyme activities

OBJECTIVES

Breast milk (BM) is the primary source of cytomegalovirus (CMV) transmission to premature infants with potentially harmful consequences. We therefore wanted to evaluate temperature and duration of short-term BM pasteurisation with respect to CMV inactivation, effect on CMV-IgG antibodies and BM enzyme activities.

METHODS

116 artificially CMV-spiked BM and 15 wild-type virus-infected samples were subjected for 5 s to different temperatures (55°C-72°C). CMV-IE-1 expression in fibroblast nuclei was assessed using the milk whey fraction in short-term microculture. BM lipase and alkaline phosphatase (AP) activities and CMV binding using CMV-recomLine immunoblotting and neutralising antibodies using epithelial target cells were analysed before and after heating.

RESULTS

A minimum of 5 s above 60°C was necessary for CMV inactivation in both CMV-AD-169 spiked and wild-type infected BM. Lipase was very heat sensitive (activities of 54% at 55°C, 5% at 60°C and 2% at 65°C). AP showed activities of 77%, 88% and 10%, respectively. CMV-p150 IgG antibodies were mostly preserved at 62°C for 5 s.

CONCLUSION

Our results show that short-term pasteurisation of BM at 62°C for 5 s might be efficient for CMV inactivation and reduces loss of enzyme activities, as well as CMV binding, and functional CMV antibodies.

Donor Milk Policies for Level 1 Newborn Care: A Descriptive Analysis

Background and Objectives: Providing pasteurized donor human milk (DHM) to healthy newborns is an emerging practice. The content of hospital policies that govern this practice is unknown. Materials and Methods: We collected policies from 15 Northeast U.S. hospitals through (1) a 2017 survey on DHM use and (2) an e-mail listserv of levels 1 and 2 newborn care staff maintained by a regional milk bank. Two authors reviewed each policy and identified how they addressed three predetermined themes: who is eligible to receive DHM, how DHM is used and described, and how lactation is supported. Responses were compared, discussed, and reconciled. Level 1 newborn care was defined as basic care for healthy newborns ≥35 weeks' gestation. Results: Thirteen of 15 policies stated criteria for DHM eligibility, most commonly as a bridge until mother's supply comes in (73%) or for infant medical conditions (67%). All required consent for DHM. Most did not limit number of days infants could receive DHM (60%). Nine specified that DHM be discarded 24 hours after thaw, whereas five recommended discarding at 48 hours. Although many (53%) policies endorsed human milk as the preferred diet for newborns, only 27% specifically endorsed DHM as the preferred supplementation type. Parent education (73%) was emphasized, but few (27%) discussed the importance of establishing mother's milk supply. Conclusions: Many DHM policies address eligibility criteria for receiving DHM and show how to provide DHM, but few address how to support lactation while DHM is provided, which may be crucial for optimizing long-term breastfeeding outcomes.

Variation and Interdependencies of Human Milk Macronutrients, Fatty Acids, Adiponectin, Insulin, and IGF-II in the European PreventCD Cohort

Human milk composition is variable. The identification of influencing factors and interdependencies of components may help to understand the physiology of lactation. In this study, we analyzed linear trends in human milk composition over time, the variation across different European countries and the influence of maternal celiac disease. Within a multicenter European study exploring potential prevention of celiac disease in a high-risk population (PreventCD), 569 human milk samples were donated by women from five European countries between 16 and 163 days postpartum. Some 202 mothers provided two samples at different time points. Protein, carbohydrates, fat and fatty acids, insulin, adiponectin, and insulin-like growth factor II (IGF-II) were analyzed. Milk protein and n-6 long chain polyunsaturated fatty acids decreased during the first three months of lactation. Fatty acid composition was significantly influenced by the country of residence. IGF-II and adiponectin concentrations correlated with protein content (r = 0.24 and r = 0.35), and IGF-II also correlated with fat content (r = 0.36), suggesting a possible regulatory role of IGF in milk macronutrient synthesis. Regarding the impact of celiac disease, only the level in palmitic acid was influenced by this disease, suggesting that breastfeeding by celiac disease mothers should not be discouraged.

Availability of Donor Milk for Very Preterm Infants Decreased the Risk of Necrotizing Enterocolitis without Adversely Impacting Growth or Rates of Breastfeeding

Human milk contains non-nutritional factors that promote intestinal maturation and protect against infectious and inflammatory conditions. In the Neonatal Intensive Care Unit (NICU) setting, donor milk (DM) is recommended when availability of own mother's milk (OMM) is not enough. Our aim was to compare the incidence of necrotizing enterocolitis (NEC) and late-onset sepsis (LOS) in very preterm infants (VPI) after the introduction of DM. Growth and breastfeeding rates were examined as secondary outcomes. Single center, observational and retrospective cohort study comparing 227 VPI admitted to our neonatal unit before (Group 1, n = 99) and after (Group 2, n = 128) DM introduction. Enteral nutrition was started earlier after DM availability (2.6 ± 1.1 vs. 2.1 ± 1 days, p = 0.001). Incidence of NEC decreased in group 2 (9.1% vs. 3.4%, p = 0.055), especially in those born between 28 and 32 weeks (5.4 vs. 0.0%, p = 0.044). Surgical NEC was also less frequent. Suffering NEC was 4 times more likely in group 1 (multivariate analysis). Availability of DM did not impact breastfeeding rates or preterm growth. Our findings support the protective role of DM against NEC, particularly in non-extreme VPI, a group less frequently included in clinical guidelines and research studies on the use of DM.

Innovative Techniques of Processing Human Milk to Preserve Key Components

Human milk not only contains all nutritional elements that an infant requires, but is also the source of components whose regulatory role was confirmed by demonstrating health-related deficiencies in formula-fed children. A human milk diet is especially important for premature babies in the neonatal intensive care unit (NICU). In cases where breastfeeding is not possible and the mother's own milk is insufficient in volume, the most preferred food is pasteurized donor milk. The number of human milk banks has increased recently but their technical infrastructure is continuously developing. Heat treatment at a low temperature and long time, also known as holder pasteurization (62.5 °C, 30 min), is the most widespread method of human milk processing, whose effects on the quality of donor milk is well documented. Holder pasteurization destroys vegetative forms of bacteria and most viruses including human immunodeficiency virus (HIV) herpes and cytomegalovirus (CMV). The macronutrients remain relatively intact but various beneficial components are destroyed completely or compromised. Enzymes and immune cells are the most heat sensitive elements. The bactericidal capacity of heat-pasteurized milk is lower than that of untreated milk. The aim of the study was for a comprehensive comparison of currently tested methods of improving the preservation stage. Innovative techniques of milk processing should minimize the risk of milk-borne infections and preserve the bioactivity of this complex biological fluid better than the holder method. In the present paper, the most promising thermal pasteurization condition (72 °C-75 °C,) and a few non-thermal processes were discussed (high pressure processing, microwave irradiation). This narrative review presents an overview of methods of human milk preservation that have been explored to improve the safety and quality of donor milk.

A Modified Holder Pasteurization Method for Donor Human Milk: Preliminary Data

Background: Holder pasteurization (HoP) is the recommended method of pasteurization for donor human milk (DHM). The aim of the present study was to compare nutritional and microbiological impact on DHM of a new technique of pasteurization based on technical changes of HoP. Methods: We analyzed milk samples from 25 donors. Each sample, derived from one breast milk expression, was subdivided into three aliquots according to pasteurization: The first was not pasteurized, the second pasteurized by HoP, and the third was pasteurized by modified HoP (MHoP). Each aliquot was assessed as to its microbiological and nutritional profile. Nutritional profile included calcium and triglycerides concentrations detected by spectrophotometry and amino acid levels assessed by high-performance liquid chromatography (HPLC). Results: Triglycerides were significantly lower in pasteurized, by both methods, than in not pasteurized aliquots, while calcium and amino acids concentration were similar. Microbiological profile did not differ between HoP and MHoP aliquots. Conclusions: HoP and MHoP seem to have similar efficacy in preserving some nutritional characteristics of DHM and to confer similar microbiological safety. MHoP is time-saving and potentially costs-effective when compared to HoP, and it is; therefore, potentially of more interest from a practical point of view. Further studies are needed to confirm these findings.

Human Breast Milk-acquired Cytomegalovirus Infection: Certainties, Doubts and Perspectives

Breast Milk (BM) is the best source of nutrition for newborns, especially if premature. In fact, its beneficial impact on short- and the long-term neonatal outcome has was deeply described. Unfortunately, BM could not be always so safe, especially due to the possible presence of maternal viruses that can be shed and transferred to the breastfed neonate. Among these, Cytomegalovirus (CMV) can potentially lead to a serious and acute illness, mostly in case of low gestational age. Some studies also report the association of CMV-acquired infection to an increased risk of structural and functional brain modifications and neurological impairment. Due to these reasons, a strategy to remove CMV from BM with a minimal or absent impact on its beneficial components would be desirable. Up to now, pasteurization, freezing, ultraviolet- C or microwave irradiation are the available techniques; they show different levels of efficacy and variable effects on BM composition, even if many studies are still needed to fully clarify these implications. In this review, we provide an update of the current evidence about these topics. We focus on the factors promoting CMV shedding through BM; moreover, the possible occurrence of a severe disease in preterm neonates is also described. Finally, we investigate the potential effects showed on BM properties by the strategies that prevent or reduce viral transmission, therefore influencing newborns' health, and the new techniques which could show a relevant role in the next future, such as metabolomics.

High-Temperature Short-Time Treatment of Human Milk for Bacterial Count Reduction

Background: Human milk (HM) for preterm infants will often be pasteurized for cytomegalovirus (CMV) inactivation and reduction of its bacterial count. High-temperature short-time (HTST) treatment compared to standard Holder pasteurization (HoP) reduces the impact of heat treatment on bioactive HM proteins while effectively inactivating CMV. No data are available for the efficacy of bacterial count reduction using HTST treatments that are available for clinical use. Objective: To test the antiviral and antibacterial efficacy of HTST treatment protocols in HM using a modified HTST treatment device compared to standard HoP. Methods: Holder pasteurized 95 mL HM samples were inoculated with Staphylococcus aureus (ATCC 6538), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Serratia marcescens (Smarc 00697), two different strains of Klebsiella pneumoniae (ATCC 700603 and Kpn 01605) or spiked with 2 × 105 50% tissue culture infective dose of CMV (AD169) and subsequently subjected to HoP (62.5°C/30 min) or HTST treatment (62°C/5 s, 62°C/15 s, 72°C/5 s, 72°C/15 s, 87°C/2 s, and 87°C/5 s). Bacterial count was determined after treated HM was cultured for 24 h. CMV infectivity was determined by the number of specific CMV immediate early antigen stained nuclei after inoculating human fibroblasts with appropriately prepared HM samples. Results: Holder pasteurized samples revealed no growth after 24 h incubation. Viable bacterial cultures were retrieved from all tested strains after HTST treatment with the default HTST protocol (62°C/5 s) that is available for clinical use. Using other time-temperature combinations, growth rates of S. aureus, E. faecalis, P. aeruginosa, K. pneumoniae, K. pneumonia, and S. marcescens were depending on treatment time, treatment temperature, bacterial genera and strain. Only after treatment temperatures above 72°C no bacterial growth was observed. CMV was inactivated by any tested time-temperature combination. Conclusions: HTST treatment inactivates CMV in 95 mL HM samples but is less effective than HoP in bacterial count reduction at a time-temperature combination of 62°C/5 s. For a reliable bacterial count reduction HTST treatment at 87°C was required in this study.

Retrospective cohort analysis on pancreatic enzyme substitution in very low birthweight infants with postnatal growth failure

OBJECTIVE

To evaluate the effects of pancreatic enzyme substitution (PES) in selected very low birthweight (VLBW) infants with poor postnatal growth despite intensified nutritional support.

DESIGN

Retrospective historic cohort study with matched controls.

SETTING

Single level III neonatal intensive care unit.

PATIENTS

Infants with a gestational age at birth <32 weeks and birth weight <1500 g born between 1 January 2005 and 31 December 2014 (n=26) who received PES for restricted postnatal growth despite intensified enteral nutritional support in comparison with infants matched for birth weight, birth year, gestational and postnatal age (n=52).

INTERVENTIONS

PES 15-93 mg/g fat with enteral feeds.

MAIN OUTCOME MEASURES

The difference in SD score (SDS) differences for weight during the 7 days before and after onset of PES and weight gain in g/kg/d. Data are presented as median (P10-P90).

RESULTS

Gestational age was 26.6 (24.4-29.9) weeks in enzyme substituted versus 26.4 (24.7-29.9) weeks in matched controls, and birth weight was 648(420-950)g versus 685(453-949)g. SDS differences for weight improved after onset of PES by 0.18(-0.12 to 0.53) in PES infants versus -0.04(-0.31 to 0.44) in controls. Weight gain increased in the PES group from 13.6 (4.2-22.9) g/kg/day in the week before to 19.0 (10.9-29.1) g/kg/day in the week after the onset of PES. There was no difference in weight gain in substituted subgroups receiving formula/pasteurised human milk versus unpasteurised human breast milk or who had pancreatic-specific elastase-1 concentrations in stool >200 µg/g versus≤200 µg/g. No adverse effects were noted.

CONCLUSIONS

PES in selected VLBW infants with growth failure despite intensified enteral nutritional support was associated with a significant increase in weight gain in the first 7 days of PES.k.

High-Temperature Short-Time Pasteurization System for Donor Milk in a Human Milk Bank Setting

Donor milk is the best alternative for the feeding of preterm newborns when mother's own milk is unavailable. For safety reasons, it is usually pasteurized by the Holder method (62.5°C for 30 min). Holder pasteurization results in a microbiological safe product but impairs the activity of many biologically active compounds such as immunoglobulins, enzymes, cytokines, growth factors, hormones or oxidative stress markers. High-temperature short-time (HTST) pasteurization has been proposed as an alternative for a better preservation of some of the biological components of human milk although, at present, there is no equipment available to perform this treatment under the current conditions of a human milk bank. In this work, the specific needs of a human milk bank setting were considered to design an HTST equipment for the continuous and adaptable (time-temperature combination) processing of donor milk. Microbiological quality, activity of indicator enzymes and indices for thermal damage of milk were evaluated before and after HTST treatment of 14 batches of donor milk using different temperature and time combinations and compared to the results obtained after Holder pasteurization. The HTST system has accurate and simple operation, allows the pasteurization of variable amounts of donor milk and reduces processing time and labor force. HTST processing at 72°C for, at least, 10 s efficiently destroyed all vegetative forms of microorganisms present initially in raw donor milk although sporulated Bacillus sp. survived this treatment. Alkaline phosphatase was completely destroyed after HTST processing at 72 and 75°C, but γ-glutamil transpeptidase showed higher thermoresistance. Furosine concentrations in HTST-treated donor milk were lower than after Holder pasteurization and lactulose content for HTST-treated donor milk was below the detection limit of analytical method (10 mg/L). In conclusion, processing of donor milk at 72°C for at least 10 s in this HTST system allows to achieve the microbiological safety objectives established in the milk bank while having a lower impact regarding the heat damage of the milk.

Evaluation of Fetal Intestinal Cell Growth and Antimicrobial Biofunctionalities of Donor Human Milk After Preparative Processes

BACKGROUND

Donor human milk is considered the next best nutrition following mother's own milk to prevent neonatal infection and necrotizing enterocolitis in preterm infants who are admitted at neonatal intensive care unit. However, donor milk biofunctionalities after preparative processes have rarely been documented.

OBJECTIVE

To evaluate biofunctionalities preserved in donor milk after preparative processes by cell-based assays.

MATERIALS AND METHODS

Ten pools of donor milk were produced from 40 independent specimens. After preparative processes, including bacterial elimination methods (holder pasteurization and cold-sterilization microfiltration) and storage conditions (-20°C freezing storage and lyophilization) with varied duration of storage (0, 3, and 6, months), donor milk biofunctionalities were examined by fetal intestinal cell growth and antimicrobial assays.

RESULTS

At baseline, raw donor milk exhibited 193.1% ± 12.3% of fetal intestinal cell growth and 42.4% ± 11.8% of antimicrobial activities against Escherichia coli. After bacteria eliminating processes, growth promoting activity was better preserved in pasteurized donor milk than microfiltrated donor milk (169.5% ± 14.3% versus 146.0% ± 11.8%, respectively; p < 0.005), whereas antimicrobial activity showed no difference between groups (38.3% ± 14.1% versus 53.7% ± 17.3%, respectively; p = 0.499). The pasteurized donor milk was further examined for the effects of storage conditions at 3 and 6 months. Freezing storage, but not lyophilization, could preserve higher growth-promoting activity during 6 months of storage (163.0% ± 9.4% versus 72.8% ± 6.2%, respectively; p < 0.005). Nonetheless, antimicrobial activity was lost at 6 months, regardless of the storage methods.

CONCLUSIONS

This study revealed that fetal intestinal cell growth and antimicrobial assays could be applied to measure donor milk biofunctionalities and support the utilization of donor milk within 3 months after preparative processes.

Composition and Variation of Macronutrients, Immune Proteins, and Human Milk Oligosaccharides in Human Milk From Nonprofit and Commercial Milk Banks

BACKGROUND

When human milk is unavailable, banked milk is recommended for feeding premature infants. Milk banks use processes to eliminate pathogens; however, variability among methods exists. Research aim: The aim of this study was to compare the macronutrient (protein, carbohydrate, fat, energy), immune-protective protein, and human milk oligosaccharide (HMO) content of human milk from three independent milk banks that use pasteurization (Holder vs. vat techniques) or retort sterilization.

METHODS

Randomly acquired human milk samples from three different milk banks ( n = 3 from each bank) were analyzed for macronutrient concentrations using a Fourier transform mid-infrared spectroscopy human milk analyzer. The concentrations of IgA, IgM, IgG, lactoferrin, lysozyme, α-lactalbumin, α antitrypsin, casein, and HMO were analyzed by mass spectrometry.

RESULTS

The concentrations of protein and fat were significantly ( p < .05) less in the retort sterilized compared with the Holder and vat pasteurized samples, respectively. The concentrations of all immune-modulating proteins were significantly ( p < .05) less in the retort sterilized samples compared with vat and/or Holder pasteurized samples. The total HMO concentration and HMOs containing fucose, sialic acid, and nonfucosylated neutral sugars were significantly ( p < .05) less in retort sterilized compared with Holder pasteurized samples.

CONCLUSION

Random milk samples that had undergone retort sterilization had significantly less immune-protective proteins and total and specific HMOs compared with samples that had undergone Holder and vat pasteurization. These data suggest that further analysis of the effect of retort sterilization on human milk components is needed prior to widespread adoption of this process.

Effect of HTST and Holder Pasteurization on the Concentration of Immunoglobulins, Growth Factors, and Hormones in Donor Human Milk

Donor human milk (DHM) is submitted to Holder pasteurization (HoP) to ensure its microbiological safety in human milk banks but this treatment affects some of its bioactive compounds. The objective of this work was to compare the effects of HoP and high temperature short time (HTST) treatments on some bioactive compounds found in DHM. A total of 24 DHM batches were processed in a continuous HTST system (70, 72, and 75°C for 5-25 s) and by HoP (62.5°C for 30 min). The concentrations of immunoglobulins (Igs) A, G, and M, transforming growth factor-beta 2 (TGF-β₂), adiponectine, ghrelin, and leptin were measured using a multiplex system, whereas the concentration of epidermal growth factor (EGF) was determined by ELISA. In relation to Igs, IgG showed the highest preservation rates (87-101%) after HTST treatments, followed by IgA (54-88%) and IgM (25-73%). Ig retention after any of the HTST treatments was higher than after HoP (p < 0.001). Treatment times required to reduce the concentration of IgM by 90% (D-value) were 130, 88, and 49 s at 70, 72, and 75°C, while the number of degrees Celsius required to change the D-value by one factor of 10 (z-value) was 11.79°C. None of the heat treatments had a significant effect on the concentrations of TGF-β₂, EGF, adiponectin, and ghrelin. In contrast, leptin was detected only in 4 of the samples submitted to HoP, whereas it was present in all samples after the different HTST treatments, with retention rates ranging between 34 and 68%. Globally, the concentration of IgA, IgG, IgM, and leptin in DHM was significantly higher after HTST pasteurization performed in a continuous system designed to be used in human milk banks than after the HoP procedure that is routinely applied at present.

Analysis of the IGF-system in milk from farm animals - Occurrence, regulation, and biomarker potential

IGFs and IGF-binding proteins (IGFBPs) are abundantly present in milk and in dairy products. Compared to the IGFs, the IGFBP have received less attention in milk, although truncated IGFBPs and IGFBP-glycosylation have been described in milk. Thereby, complex control of local IGF-effects can be assumed on the levels of IGFBPs, proteases, and protease inhibitors. The present review collects the current knowledge both on presence and regulation of IGFs and IGFBPs in milk particularly from dairy animal species. As a rule higher levels of IGF-I, IGF-II, and IGFBPs are measured around parturition if compared to later time-points of lactation. In all farm animal species included in this review, it is found that the relative abundancies of IGFBPs in milk and serum are similar, with IGFBP-3 and -2 characterized by higher concentrations if compared to IGFBP-4 or -5. The concentrations of IGFs and IGFBPs in milk or dairy products can be altered by hormones, dairy processing, or fermentation. Because milk can be used for non-invasive biomarker research, quality management, and health monitoring, we discuss novel directions of IGF-analysis and potential on-site biomarker research in milk.

High-temperature short-time pasteurisation of human breastmilk is efficient in retaining protein and reducing the bacterial count

AIM

Milk banks are advised to use Holder pasteurisation to inactivate the cytomegalovirus, but the process adversely affects the bioactive properties of human breastmilk. This study explored the antibacterial efficacy of an alternative high-temperature short-time (HTST) treatment of human breastmilk and its effect on marker proteins, compared with the Holder method.

METHODS

Breastmilk samples were obtained from 27 mothers with infants in a German neonatal intensive care unit. The samples were either heated to 62°C for five seconds using HTST or processed using Holder pasteurisation, at 63 ± 0.5°C for 30 minutes. Immunoglobulin A, lactoferrin, lysozyme, alkaline phosphatase and bile salt-stimulated lipase concentrations and bacterial colony-forming units/mL were measured before and after heating.

RESULTS

HTST-treated samples retained higher rates of immunoglobulin A (95% versus 83%), alkaline phosphatase (6% versus 0%) and bile salt-stimulated lipase (0.8% versus 0.4%) than Holder pasteurisation samples (all p < 0.01), but not lactoferrin (32% versus 20%, p = 0.18) and lysozyme (72% versus 65%, p = 1). No difference in antibacterial efficacy was noted between the two groups (p = 0.29).

CONCLUSION

Using the HTST treatment protocol retained some of the bioactive properties of human breastmilk and appeared to have similar antibacterial efficacy to Holder pasteurisation.

Human Milk Processing: A Systematic Review of Innovative Techniques to Ensure the Safety and Quality of Donor Milk

Pasteurization, performed at 62.5°C for 30 minutes (holder pasteurization), is currently recommended in all international human milk banks guidelines, but it affects some human milk bioactive and nutritive components. The present systematic review is aimed at critically reviewing evidence on the suitability of human milk processing techniques other than holder pasteurization, both thermal and nonthermal, to ensure microbiological safety, and on the effects of these techniques on biologically active donor milk components. A systematic review of English and non-English articles using Medline, PubMed, Embase, SCOPUS, and CAB Abstracts, with no restriction in publication date was performed. Search terms included: human, breast, donor, or banked milk, breastmilk, breast fed, breastfed, breastfeed; HTST, Flash, High Pressure, UV, ultrasonic or nonthermal; process, pasteuris, pasteuriz. Only primary research articles published in peer-reviewed journals were included, providing or not a comparison with holder pasteurized human milk, provided that the pasteurization technique was clearly described, and not intended for domestic use. Additional studies were identified by searching bibliographies of relevant articles. Twenty-six studies were identified as being relevant. Two examined both High Pressure Processing and High-Temperature-Short-Time pasteurization; 10 only examined High Pressure Processing; 10 only examined High-Temperature-Short-Time; 2 articles examined ultraviolet irradiation; 2 articles examined (thermo-)ultrasonic processing. The results indicate that data about safety for microbiological control are still scarce for most of the novel technologies, and that consensus on processing conditions is necessary for nonthermal technologies, before any conclusions on the qualitative and nutritional advantages of these techniques can be drawn.

Human Milk-Treatment and Quality of Banked Human Milk

The aim of human milk banks is to deliver safe and high quality donor human milk. Treatment of human milk has to destroy most microorganisms while preserving immunological and nutrient components, which is obtained when using low time low temperature pasteurization. However it destroys bile-simulated lipase, reduces lactoferrin, lysozyme, immunoglobulins, and bactericidal capacity of human milk. New methods are under investigation such as high temperature short time pasteurization, high pressure processing, or ultraviolet irradiation. They have been tested in experimental conditions and there are promising results, but they have to be tested in real conditions in human milk bank.

Postnatal Cytomegalovirus Infection Through Human Milk in Preterm Infants: Transmission, Clinical Presentation, and Prevention

Cytomegalovirus (CMV) is reactivated in the lactating breast in up to 96% of CMV seropositive mothers. There is a relevant entity of postnatally acquired symptomatic CMV infection and disease of preterm infants through raw breast milk (BM). Actual data support negative influence on long-term cognitive development. Concerning prevention, only heat inactivation eliminates virus infectivity, and short-term heat inactivation is most preservative; this can be applied effectively under routine conditions. Short-term heat inactivation for 5 minutes at 62°C maintains the benefits of feeding BM without the disadvantages of CMV transmission.

Effect of Early Expressed Human Milk on Insulin-Like Growth Factor 1 and Short-Term Outcomes in Preterm Infants

Aims

Preterm breast milk contains high levels of bioactive components, including insulin-like growth factor 1 (IGF-1), that are reduced by Holder pasteurization. Animal studies have shown that milk-borne IGF-1 is likely absorbed intact in a bioactive form by the intestines. The aim of this study was to assess if early non-pasteurized expressed breast milk nutrition may affect IGF-1 plasma levels in premature infants. We also investigated the possible association between early expressed milk nutrition and short-term outcomes.

Methods

Fifty-two preterm infants with gestational age < 31 weeks were divided into two groups according to expressed breast milk intake (< or ≥ 50 mL/Kg/day) until 32 weeks of postmenstrual age when blood sampling for IGF-1 analysis was performed.

Results

In our population, early expressed breast milk does not affect IGF-1 plasma levels (p 0.48). An association was observed between early expressed milk nutrition and a lower incidence of bronchopulmonary dysplasia, sepsis, feeding intolerance, need for parenteral nutrition and length of hospitalization.

Conclusions

Contrary to the results in some animal studies, our results did not seem to show that early expressed breast milk can help to maintain postnatal IGF-1 near foetal levels in preterm infants. The observed protective effect of expressed breast milk on short-term outcomes can be the starting point for further study of the effects of non-pasteurized human milk in preterm infants.

The Effect of Holder Pasteurization on Nutrients and Biologically-Active Components in Donor Human Milk: A Review

When a mother's milk is unavailable, the best alternative is donor milk (DM). Milk delivered to Human Milk Banks should be pasteurized in order to inactivate the microbial agents that may be present. Currently, pasteurization, performed at 62.5 °C for 30 min (Holder Pasteurization, HoP), is recommended for this purpose in international guidelines. Several studies have been performed to investigate the effects of HoP on the properties of DM. The present paper has the aim of reviewing the published papers on this topic, and to provide a comparison of the reported variations of biologically-active DM components before and after HoP. This review was performed by searching the MEDLINE, EMBASE, CINHAL and Cochrane Library databases. Studies that clearly identified the HoP parameters and compared the same DM samples, before and after pasteurization, were focused on. A total of 44 articles satisfied the above criteria, and were therefore selected. The findings from the literature report variable results. A possible explanation for this may be the heterogeneity of the test protocols that were applied. Moreover, the present review spans more than five decades, and modern pasteurizers may be able to modify the degradation kinetics for heat-sensitive substances, compared to older ones. Overall, the data indicate that HoP affects several milk components, although it is difficult to quantify the degradation degree. However, clinical practices demonstrate that many beneficial properties of DM still persist after HoP.

Increased Cytomegalovirus Secretion and Risks of Infant Infection by Breastfeeding Duration From Maternal Human Immunodeficiency Virus Positive Compared to Negative Mothers in Sub-Saharan Africa

BACKGROUND

Breastfeeding imparts beneficial immune protection and nutrition to infants for healthy growth, but it is also a route for human immunodeficiency virus (HIV) and human cytomegalovirus (HCMV) infection. In previous studies, we showed that HCMV adversely affects infant development in Africa, particularly with maternal HIV exposure. In this study, we analyzed infants risks for acquisition of HCMV infection from breastfeeding and compared HIV-positive and HIV-negative mothers.

METHODS

Two cohorts were studied in Zambia. (1) Two hundred sixty-one HIV-infected and HIV-uninfected mothers were compared for HCMV deoxyribonucleic acid (DNA) loads and genotypes (glycoprotein gO) in milk from birth to 4 months postpartum. (2) Maternally HIV-exposed and HIV-unexposed infants were compared for HCMV infection risk factors. The second cohort of 460 infants, from a trial of micronutrient-fortified complementary-food to breastfeeding, were studied between 6 and 18 months of age. Human cytomegalovirus seroprevalence was assayed, and logistic regression was used to calculate risk factors for HCMV infection, including maternal HIV exposure and breastfeeding duration.

RESULTS

Human cytomegalovirus was detected in breast milk from 3 days to 4 months postpartum, with significantly raised levels in HIV-positive women and independent of genotype. In infants, HCMV antibody seroprevalence was 83% by 18 months age. Longer breastfeeding duration increased infection risk in maternally HIV-unexposed (odds ratio [OR] = 2.69 for 18 months vs <12 months; 95% confidence interval [CI], 0.84-8.59; P = .03) and HIV-exposed infants (OR = 20.37 for >6 months vs never; 95% CI, 3.71-111.70; P < .001).

CONCLUSIONS

Prolonged breastfeeding, which is common in Africa, increased risk of HCMV infection in infants. Both HIV-positive and HIV-negative women had extended milk HCMV secretion. Women who were HIV-positive secreted higher HCMV levels, and for longer duration, with their children at increased infection risk. Human cytomegalovirus control is required to maintain health benefits of breastfeeding.

Effects of Holder pasteurization on the protein profile of human milk

BACKGROUND

The most widespread method for the treatment of donor milk is the Holder pasteurization (HoP). The available literature data show that HoP may cause degradation of some bioactive components. The aim of this study was to determine the effect of HoP on the protein profile of human milk (HM) using a GeLC-MS method, a proteomic approach and a promising technique able to offer a qualitative HM protein profile.

METHODS

HM samples were collected by standardized methods from 20 mothers carrying both preterm and term newborns. A aliquot of each sample was immediately frozen at -80 °C, whilst another one was Holder pasteurized and then frozen. All samples were then analyzed by GeLC-MS. The protein bands of interest were excised from the gel, digested with trypsin and identified by nano-HPLC-MS/MS analysis.

RESULTS

The protein profile before and after HoP showed qualitative differences only in 6 samples out of 20, while in the remaining 14 no detectable differences were found. The differences interested only colostrums and transitional milk samples and regarded the decrease of the electrophoretic bands corresponding to alpha and beta-casein, tenascin, lactoferrin and immunoglobulin.

CONCLUSIONS

In the majority of samples, HoP did not cause any modification, thereby preserving the biological activity of HM proteins.

Pasteurization of breastmilk decreases the rate of postnatally acquired cytomegalovirus infections, but shows a nonsignificant trend to an increased rate of necrotizing enterocolitis in very preterm infants--a preliminary study

AIM

This study assessed whether feeding preterm infants unpasteurized breastmilk (1) decreases the rate of late-onset sepsis and necrotizing enterocolitis and (2) increases the rate of postnatally acquired cytomegalovirus infections.

SUBJECTS AND METHODS

Between January 2008 and July 2013, preterm infants below 32 completed weeks of gestational age admitted to the neonatal intensive care unit of Innsbruck Medical University (Innsbruck, Austria) (n=344) were eligible for the study. Of those, 323 fed breastmilk were retrospectively enrolled in the study. Two groups were formed, with 164 infants being fed unpasteurized and 159 infants being fed pasteurized breastmilk.

RESULTS

There was no significant difference in the rate of late-onset sepsis or necrotizing enterocolitis between the unpasteurized and pasteurized breastmilk groups (late-onset sepsis, 15.9% versus 15.1% [p=0.486]; necrotizing enterocolitis, 2.4% versus 4.4% [p=0.254]). The number of infants diagnosed with postnatally acquired cytomegalovirus infection was significantly higher in the unpasteurized group (39.3%) compared with the pasteurized group (4.2%) (p=0.008).

CONCLUSIONS

Feeding preterm infants unpasteurized breastmilk increases the rate of postnatally acquired cytomegalovirus infections. However, we also demonstrate a nonsignificant trend to a decreased rate of necrotizing enterocolitis in the unpasteurized group, which needs to be confirmed in larger studies.

[Study of the effects of the implementation of a human milk donor bank in preterm newborns in Aragon]

INTRODUCTION

Numerous obstacles may prevent a premature or sick neonate receiving their mother's milk. In these cases, pediatric scientific societies recommend feeding with donor human milk. In this article, it is explained what a milk bank is, how it works, the donors' selection method, and the benefits. We also describe the current situation in Aragon (Spain) is also described.

MATERIAL AND METHODS

A retrospective and descriptive study was conducted on the perinatal sample characteristics, as well as an analytical observational study, comparing two sample groups: pre- and post-human milk bank. Finally, differences in the post-bank stage between those patients fed with own-mother's or donor human milk were determined.

RESULTS

The study included a total of 234 patients: 104 females and 130 males. Two groups: pre and post-bank, with 152 and 82 patients, respectively, which had similar characteristics at birth; length and head circumference were significantly higher in the post-bank group and a lower rate of necrotizing enterocolitis was also found. No statistically significant differences were found in other variables between subgroups fed with own-mother's milk and donor human milk.

DISCUSSION

The establishment of the human milk donor bank has a beneficial effect, as it reduces neonatal morbidity in cases of necrotizing enterocolitis. Human milk feeding could be a protective factor against neonatal sepsis due to improve immunity.

CONCLUSIONS

The incidence of necrotizing enterocolitis is lower after the establishment of the milk bank. Studies with more patients may demonstrate differences in other variables.

Transmission of human cytomegalovirus via breastmilk and potential risks to very preterm infants

Breastfeeding has clear short-term benefits for the baby1. Additionally, based on a prospective long-term cohort study from Brazil, breastfeeding is associated with improved IQ scores and increased educational attainment 30 years later2. During lactation, mother-to-infant transmission of viral infections like HIV, hepatitis B (HBV), and human cytomegalovirus (HCMV), may occur. The article presented here will focus on the dynamics of HCMV shedding into breastmilk, describe the short- and long-term risks of HCMV infection of small preterm infants, and options for prevention.

Blood transfusion and breast milk transmission of cytomegalovirus in very low-birth-weight infants: a prospective cohort study

IMPORTANCE

Postnatal cytomegalovirus (CMV) infection can cause serious morbidity and mortality in very low-birth-weight (VLBW) infants. The primary sources of postnatal CMV infection in this population are breast milk and blood transfusion. The current risks attributable to these vectors, as well as the efficacy of approaches to prevent CMV transmission, are poorly characterized.

OBJECTIVE

To estimate the risk of postnatal CMV transmission from 2 sources: (1) transfusion of CMV-seronegative and leukoreduced blood and (2) maternal breast milk.

DESIGN, SETTING, AND PARTICIPANTS

A prospective, multicenter birth-cohort study was conducted from January 2010 to June 2013 at 3 neonatal intensive care units (2 academically affiliated and 1 private) in Atlanta, Georgia. Cytomegalovirus serologic testing of enrolled mothers was performed to determine their status. Cytomegalovirus nucleic acid testing (NAT) of transfused blood components and breast milk was performed to identify sources of CMV transmission. A total of 539 VLBW infants (birth weight, ≤ 1500 g) who had not received a blood transfusion were enrolled, with their mothers (n = 462), within 5 days of birth. The infants underwent serum and urine CMV NAT at birth to evaluate congenital infection and surveillance CMV NAT at 5 additional intervals between birth and 90 days, discharge, or death.

EXPOSURES

Blood transfusion and breast milk feeding.

MAIN OUTCOMES AND MEASURES

Cumulative incidence of postnatal CMV infection, detected by serum or urine NAT.

RESULTS

The seroprevalence of CMV among the 462 enrolled mothers was 76.2% (n = 352). Among the 539 VLBW infants, the cumulative incidence of postnatal CMV infection at 12 weeks was 6.9% (95% CI, 4.2%-9.2%); 5 of 29 infants (17.2%) with postnatal CMV infection developed symptomatic disease or died. A total of 2061 transfusions were administered among 57.5% (n = 310) of the infants; none of the CMV infections was linked to transfusion, resulting in a CMV infection incidence of 0.0% (95% CI, 0.0%-0.3%) per unit of CMV-seronegative and leukoreduced blood. Twenty-seven of 28 postnatal infections occurred among infants fed CMV-positive breast milk (12-week incidence, 15.3%; 95% CI, 9.3%-20.2%).

CONCLUSIONS AND RELEVANCE

Transfusion of CMV-seronegative and leukoreduced blood products effectively prevents transmission of CMV to VLBW infants. Among infants whose care is managed with this transfusion approach, maternal breast milk is the primary source of postnatal CMV infection.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00907686.

Cytokines, Chemokines, and Growth Factors in Banked Human Donor Milk for Preterm Infants

BACKGROUND

There has been a recent increase in availability of banked donor milk for feeding of preterm infants. This milk is pooled from donations to milk banks from carefully screened lactating women. The milk is then pasteurized by the Holder method to remove all microbes. The processed milk is frozen, banked, and sold to neonatal intensive care units (NICUs). The nutrient bioavailability of banked donor milk has been described, but little is known about preservation of immune components such as cytokines, chemokines, and growth factors (CCGF).

OBJECTIVE

The objective was to compare CCGF in banked donor milk with mother's own milk (MOM).

METHODS

Aliquots (0.5 mL) were collected daily from MOM pumped by 45 mothers of NICU-admitted infants weighing < 1500 grams at birth. All daily aliquots of each mother's milk were pooled each week during 6 weeks of an infant's NICU stay or for as long as the mother provided MOM. The weekly pooled milk was measured for a panel of CCGF through multiplexing using magnetic beads and a MAGPIX instrument. Banked donor milk samples (n = 25) were handled and measured in the same way as MOM.

RESULTS

Multiplex analysis revealed that there were levels of CCGF in banked donor milk samples comparable to values obtained from MOM after 6 weeks of lactation.

CONCLUSION

These data suggest that many important CCGF are not destroyed by Holder pasteurization.

DoMINO: Donor milk for improved neurodevelopmental outcomes

BACKGROUND

Provision of mother's own milk is the optimal way to feed infants, including very low birth weight infants (VLBW, <1500 g). Importantly for VLBW infants, who are at elevated risk of neurologic sequelae, mother's own milk has been shown to enhance neurocognitive development. Unfortunately, the majority of mothers of VLBW infants are unable to provide an adequate supply of milk and thus supplementation with formula or donor milk is necessary. Given the association between mother's own milk and neurodevelopment, it is important to ascertain whether provision of human donor milk as a supplement may yield superior neurodevelopmental outcomes compared to formula.Our primary hypothesis is that VLBW infants fed pasteurized donor milk compared to preterm formula as a supplement to mother's own milk for 90 days or until hospital discharge, whichever comes first, will have an improved cognitive outcome as measured at 18 months corrected age on the Bayley Scales of Infant Development, 3(rd) ed. Secondary hypotheses are that the use of pasteurized donor milk will: (1) reduce a composite of death and serious morbidity; (2) support growth; and (3) improve language and motor development. Exploratory research questions include: Will use of pasteurized donor milk: (1) influence feeding tolerance and nutrient intake (2) have an acceptable cost effectiveness from a comprehensive societal perspective?

METHODS/DESIGN

DoMINO is a multi-centre, intent-to-treat, double blinded, randomized control trial. VLBW infants (n = 363) were randomized within four days of birth to either (1) pasteurized donor milk or (2) preterm formula whenever mother's own milk was unavailable. Study recruitment began in October 2010 and was completed in December 2012. The 90 day feeding intervention is complete and long-term follow-up is underway.

DISCUSSION

Preterm birth and its complications are a leading cause long-term morbidity among Canadian children. Strategies to mitigate this risk are urgently required. As mother's own milk has been shown to improve neurodevelopment, it is essential to ascertain whether pasteurized donor milk will confer the same advantage over formula without undue risks and at acceptable costs. Knowledge translation from this trial will be pivotal in setting donor milk policy in Canada and beyond.

TRIAL REGISTRATION

ISRCTN35317141; Registered 10 August 2010.

High rate of symptomatic cytomegalovirus infection in extremely low gestational age preterm infants of 22-24 weeks' gestation after transmission via breast milk

BACKGROUND

Very immature preterm infants are at risk of developing symptomatic or severe infection if cytomegalovirus is transmitted via breast milk. It is still a matter of debate whether human cytomegalovirus (HCMV) infection may lead to long-term sequelae.

OBJECTIVES

We hypothesized that symptomatic and severe HCMV infection transmitted via breast milk affects extremely immature infants at a very high rate.

METHODS

In 2012, untreated breast milk was fed to extremely low birth weight infants after parental informed consent was obtained. We retrospectively analyzed data on HCMV infection of infants born in 2012 between 22 and 24 weeks of gestation.

RESULTS

17 infants were born to HCMV IgG-seropositive mothers. 11 (65%) of these were diagnosed with symptomatic infection. In all cases, thrombocytopenia was the reason to analyze the infant's urine. HCMV infection was diagnosed at a median time of 12 weeks after birth. In 5 (45%) infants, thrombocytopenia was the only symptom and resolved without antiviral therapy or platelet transfusion. 6 (55%) infants developed sepsis-like disease with mildly elevated CRP values and showed signs of respiratory failure. 3 (27%) were able to be stabilized on CPAP, 3 (27%) had to be intubated and mechanically ventilated. 4 children were treated with ganciclovir and/or valganciclovir. 55% failed otoacoustic emissions and/or automated auditory brainstem response testing at discharge.

CONCLUSIONS

In very immature infants born at the border of viability and suffering from multiple preexisting problems, HCMV infection may trigger a severe deterioration of the clinical course.