Nutrition of Preterm Infants and Raw Breast Milk-Acquired Cytomegalovirus Infection: French National Audit of Clinical Practices and Diagnostic Approach

Handling of human milk to prevent acquired cytomegalovirus infection in Japanese neonatal intensive care units: The first nationwide survey

BACKGROUND

Human milk (HM) has been proven to provide immunological and nutritional advantages to neonates; however, acquired cytomegalovirus (CMV) infection can be associated with raw HM. In Japan, there are no standardized guidelines concerning HM handling. This cross-sectional survey was performed to reveal specific trends in HM handling in neonatal intensive care units (NICUs) in Japan.

METHODS

A questionnaire was sent to 255 NICUs participating in the Japanese Neonatologist Association in May 2020. It involved HM handling practices, such as maternal screening, pasteurization, storage, and the workforce.

RESULTS

Of 255 NICUs, 174 (67.8%) responded to the survey. Maternal CMV screening was carried out in 37 units (22.2%), and CMV inactivation in HM was performed in 44 units (26.5%). For CMV inactivation, a freeze-thawing method was employed in about 90% of units. In 70% of units providing CMV inactivation, CMV inactivation was conducted regardless of bodyweight and corrected gestational age of infants until the infants' discharge. Acquired CMV infection in preterm neonates was observed in 43 units (25.7%) in the survey period.

CONCLUSION

A wide range of HM handling practices are used in Japanese NICUs. A national guideline for handling HM in NICUs should be created to promote the infection control of CMV.

Prospective cohort study for postnatal cytomegalovirus infection in preterm infants

AIM

Cytomegalovirus (CMV) is a virus that can cause congenital and postnatal infections. Postnatal CMV is mainly transmitted via breast milk and blood transfusions. Frozen-thawed breast milk is used to prevent postnatal CMV infection. A prospective cohort study was conducted to determine the infection rate, risk, and clinical findings of postnatal CMV infection.

METHODS

This prospective cohort study included infants born at 32 weeks or earlier than the gestational age (GA). Participants were prospectively screened for infection in the urine by performing urine CMV DNA tests twice, that is, once within the first 3 weeks of life and again after 35 weeks postmenstrual age (PMA). Postnatal CMV infection was defined as a case of CMV negative tests within 3 weeks of birth and CMV positive tests after 35 weeks PMA. CMV-negative blood products were used for transfusions in all cases.

RESULTS

A total of 139 patients were subjected to two urine CMV DNA tests. The prevalence of postnatal CMV infection was 5.0%. One patient died of sepsis-like syndrome. The risk factors of postnatal CMV infection were younger GA and older age of the mother. The characteristic clinical findings of postnatal CMV infection were pneumonia.

CONCLUSIONS

Frozen-thawed breast milk feeding is not fully effective in preventing postnatal CMV infection. The prevention of postnatal CMV infection is important to further improve the survival rate of preterm infants. Development of guidelines on breast milk feeding for the prevention of postnatal CMV infection is necessary in Japan.

Cytomegalovirus-related sepsis-like syndrome in very premature infants in Japan

BACKGROUND

Very premature infants are at high risk of developing a symptomatic postnatal cytomegalovirus (CMV) disease, such as CMV-related sepsis-like syndrome (CMV-SLS). To address the limited data regarding its clinical features, a nationwide survey of CMV-SLS was conducted.

METHODS

A questionnaire regarding CMV status and the clinical outcomes of CMV-SLS was sent to centers with reported cases of CMV-SLS.

RESULTS

Twelve CMV-SLS cases, nine confirmed and three probable cases, were reported during the 3-year survey period. The median gestational age and birthweight were 25 weeks and 547 g, respectively. At disease onset, the median age was 49 days, and the corrected age was 31 weeks. Untreated breast milk was given in four cases (33%), whereas frozen breast milk was given in nine (75%). No specific symptoms and laboratory data regarding CMV-SLS were found.

CONCLUSIONS

Very premature infants developed CMV-SLS after 1 month of age. There are no symptoms and signs specific for the diagnosis of CMV-SLS, so CMV-SLS should be considered as a differential diagnosis for premature infants who have unexplained sepsis-like symptoms during the convalescent phase.

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.

Incidence of Postnatal CMV Infection among Breastfed Preterm Infants: a Systematic Review and Meta-analysis

BACKGROUND

We performed a systematic review and meta-analysis to evaluate the incidence of breast milk-acquired cytomegalovirus (CMV) infection in preterm infants born to CMV-seropositive mothers.

METHODS

PubMed, Embase, and Cochrane Library databases were searched using the terms: ("breast feeding" or "breast milk" or "human milk" or "breast") and ("HCMV" or "cytomegalovirus") and ("infant, extremely premature" or "premature birth" or "newborn" or "neonate" or "low birth weight" or "very low birth weight" or "premature" or "preterm infant"). Studies that had information on CMV status and breast feeding were included in the meta-analysis.

RESULTS

A total of 2,502 newborns from 19 studies were included in this meta-analysis. The rate of postnatally acquired CMV infection among breastfed infants with CMV-seropositive mothers was 16.5% (95% confidence interval [CI], 0.10-0.26; P < 0.001). The infection rate was 26% with fresh breast milk, 8% with a combined diet of fresh and freeze-thawed breast milk, and 11% with freeze-thawed breast milk. Among cases where the CMV status of breast milk was determined, CMV shedding into breast milk occurred in 80.5% (95% CI, 0.71-0.87; P < 0.001) of CMV seropositive mothers. The breast milk-acquired CMV infection rate among infants fed CMV-positive breast milk was 20.7% (95% CI, 0.14-0.30; P < 0.001).

CONCLUSION

This meta-analysis examined the rate of breast milk-acquired CMV infections in preterm infants with CMV-seropositive mothers; the CMV infection rate was higher in preterm infants fed fresh breast milk. Until further data are available, we cautiously suggest the use of freeze-thawed breast milk, rather than fresh breast milk, for preterm infants or very low birth weight infants.

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.

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.

Challenges and Clinical Implications of the Diagnosis of Cytomegalovirus Lung Infection in Children

PURPOSE OF REVIEW

Pulmonary cytomegalovirus (CMV) infection is a potential lethal disease in children, but it remains a diagnostic challenge. The differentiation between latent CMV infections with viral shedding and active infections is difficult and may lead to false positives in bronchoalvolar lavage (BAL) PCR detection. This review summarizes current diagnostic approaches for CMV lung infection in children including progress in the identification of underlying immune defects linked to this condition.

RECENT FINDINGS

There is increasing literature supporting that the combined assessment of host risk factors and lung disease pattern is essential for the diagnosis of pulmonary CMV infection in children. The most important host risk factor is an immunecompromised state that has expanded from primary or acquired immunodeficiency (e.g., HIV) to include a myriad of immune-dysregulation syndromes (e.g., CTLA4, PIK3 defects). Newborns, paricularly those born premature, are also a high-risk group. At the pulmonary level, active CMV infection is typically characterized by alveolar compromise leading to hypoxemia, ground-glass opacities, and intra-alveolar infiltrates with CMV inclusions in lung biopsy. The identification of active CMV lung infection should trigger additional evaluation of immune defects (primary or secondary) impairing T and NK cell function or innate antiviral responses as well as other immune dysregulation disorders. Lung CMV infections in children are more prevalent in immunocompromised hosts and premature newborns. Lung CMV infections should prompt further investigation into conditions altering immune mechanisms usually in place to contain CMV infections. Common clinical and radiological patterns such as hypoxemia and ground-glass pulmonary opacities may allow early identification and treatment of CMV lung infection and underlying causes in the pediatric population.