Enteral zinc supplementation and growth in extremely-low-birth-weight infants with chronic lung disease

The Role of Zinc in Developed Countries in Pediatric Patients: A 360-Degree View

Zinc is an important trace element for growth and health at pediatric ages. Zinc is fundamental in inflammatory pathways, oxidative balance, and immune function. Zinc exhibits anti-inflammatory properties by modulating Nuclear Factor-kappa (NF-κB) activity and reducing histamine release from basophils, leukocytes, and mast cells. Furthermore, its antioxidant activity protects against oxidative damage and chronic diseases. Finally, zinc improves the ability to trigger effective immune responses against pathogens by contributing to the maturation of lymphocytes, the production of cytokines, and the regulation of apoptosis. Given these properties, zinc can be considered an adjunctive therapy in treating and preventing respiratory, nephrological, and gastrointestinal diseases, both acute and chronic. This review aims to deepen the role and metabolism of zinc, focusing on the role of supplementation in developed countries in pediatric diseases.

Nutritional Needs of the Infant with Bronchopulmonary Dysplasia

Growth failure is a common problem in infants with established bronchopulmonary dysplasia (BPD). Suboptimal growth for infants with BPD is associated with unfavorable respiratory and neurodevelopmental outcomes; however, high-quality evidence to support best nutritional practices are limited for this vulnerable patient population. Consequently, there exists a wide variation in the provision of nutritional care and monitoring of growth for infants with BPD. Other neonatal populations at risk for growth failure, such as infants with congenital heart disease, have demonstrated improved growth outcomes with the creation and compliance of clinical protocols to guide nutritional management. Developing clinical protocols to guide nutritional management for infants with BPD may similarly improve long-term outcomes. Given the absence of high-quality trials to guide nutritional practice in infants with BPD, the best available evidence of systematic reviews and clinical recommendations can be applied to optimize growth and decrease variation in the care of these infants.

Select micronutrients for the preterm neonate

If premature neonates are not provided with adequate nutrition, they will quickly become deficient because of increased requirements and a lack of nutrient stores to achieve adequate growth. The provision of many of the recommended micronutrients for pediatric and adult patients is challenging in premature neonates because of the limited data surrounding the true needs of premature neonates and the difficulty in assessing adequate serum levels of these nutrients in this patient population. Parenteral and enteral nutrition shortages further complicate providing adequate micronutrients to premature neonates. This review will discuss select micronutrients and their importance to the preterm neonate, with special emphasis on micronutrients with limited evidence and more challenging supplementation and repletion strategies.

A review and guide to nutritional care of the infant with established bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) remains the most common long-term morbidity of premature birth, and the incidence of BPD is not declining despite medical advancements. Infants with BPD are at high risk for postnatal growth failure and are often treated with therapies that suppress growth. Additionally, these infants may display excess weight gain relative to linear growth. Optimal growth and nutrition are needed to promote lung growth and repair, improve long-term pulmonary function, and improve neurodevelopmental outcomes. Linear growth in particular has been associated with favorable outcomes yet can be difficult to achieve in these patients. While there has been a significant clinical and research focus regarding BPD prevention and early preterm nutrition, there is a lack of literature regarding nutritional care of the infant with established BPD. There is even less information regarding how nutritional needs change as BPD evolves from an acute to chronic disease. This article reviews the current literature regarding nutritional challenges, enteral nutrition management, and monitoring for patients with established BPD. Additionally, this article provides a practical framework for interdisciplinary nutritional care based on our clinical experience at the Comprehensive Center for Bronchopulmonary Dysplasia.

Perspectives on developing and sustaining a small baby program

The Small Baby Program at Nationwide Children's Hospital was launched in 2004 in response to a need for better care for infants born extremely preterm. Standardization of care, decreased variability, multidisciplinary support, and robust research and quality improvement have allowed us to greatly improve our outcomes. In addition to the numerous medical and technological advances during this time, a strong commitment to kangaroo care and family-centered care have been integral to the growth and success of our program. The following review of the program aims to highlight the above areas while detailing the specific processes that have contributed to its ongoing success. Key areas of focus have been on respiratory management, neurodevelopmental care, and nutritional optimization. The implementation and continued refinement of the Small Baby Program has allowed us to improve the survival of extremely preterm infants, decrease certain morbidities, and improve long-term neurodevelopmental outcomes.

Zinc status and growth in infants and young children with cystic fibrosis

BACKGROUND

Zinc deficiency is associated with poor growth in children without cystic fibrosis (CF), but its impact on growth in children with CF is unknown.

OBJECTIVE

To determine the prevalence of low serum Zn (sZn) and its relationship with growth in the first 3 years of life in children with CF.

METHODS

We utilized data from infants with CF who were enrolled in a longitudinal study of nutrition and lung health and had sZn measured as part of clinical care. Cross-sectional correlations between sZn levels and growth z scores were assessed by Pearson's correlation coefficient. To identify factors associated with sZn status and its association to longitudinal growth patterns, multiple regression analysis with repeated measures were performed using generalized estimating equations.

RESULTS

A total of 106 sZn measurements from 53 infants were identified. Seventeen infants (32%) had intermittent Zn insufficiency, defined as at least one sZn <70 mcg/dl in their first 3 years of life. There were no significant cross-sectional associations between sZn and growth z scores. However, analysis of longitudinal growth patterns revealed that weight- and length-for-age z scores in children with intermittent Zn insufficiency were lower during early infancy and their weight-for-length z scores at age 3 years were also lower compared to those who were always Zn sufficient.

CONCLUSION

Low sZn occurs in one-third of children with CF in the first 3 years of life. Cross-sectional and longitudinal analyses revealed discrepant associations between sZn and growth. Therefore, prospective studies are needed to understand the role of Zn in growth in CF.

Nutrition and growth in infants with established bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) remains the most common late morbidity of preterm birth. Ongoing clinical care and research have largely focused on the pathogenesis and prevention of BPD in preterm infants. However, preterm infants who develop BPD have significant medical needs that persist throughout their neonatal intensive care unit course and continue post-discharge, including those associated with growth and nutrition. The objective of this manuscript was to provide a review on nutrition and growth in infants with established BPD after discharge from the hospital and to identify the knowledge and research gaps to provide direction for future studies.

Malnutrition, poor post-natal growth, intestinal dysbiosis and the developing lung

In extremely preterm infants, poor post-natal growth, intestinal dysbiosis and bronchopulmonary dysplasia are common, and each is associated with long-term complications. The central hypothesis that this review will address is that these three common conditions are interrelated. Challenges to studying this hypothesis include the understanding that malnutrition and poor post-natal growth are not synonymous and that there is not agreement on what constitutes a normal intestinal microbiota in this evolutionarily new population. If this hypothesis is supported, further study of whether "correcting" intestinal dysbiosis in extremely preterm infants reduces postnatal growth restriction and/or bronchopulmonary dysplasia is indicated.

The Role of Nutrition in the Prevention and Management of Bronchopulmonary Dysplasia: A Literature Review and Clinical Approach

Bronchopulmonary dysplasia (BPD) remains the most common severe complication of preterm birth, and nutrition plays a crucial role in lung growth and repair. A practical nutritional approach for infants at risk of BPD or with established BPD is provided based on a comprehensive literature review. Ideally, infants with BPD should receive a fluid intake of not more than 135-150 mL/kg/day and an energy intake of 120-150 kcal/kg/day. Providing high energy in low volume remains a challenge and is the main cause of growth restriction in these infants. They need a nutritional strategy that encompasses early aggressive parenteral nutrition and the initiation of concentrated feedings of energy and nutrients. The order of priority is fortified mother's own milk, followed by fortified donor milk and preterm enriched formulas. Functional nutrient supplements with a potential protective role against BPD are revisited, despite the limited evidence of their efficacy. Specialized nutritional strategies may be necessary to overcome difficulties common in BPD infants, such as gastroesophageal reflux and poorly coordinated feeding. Planning nutrition support after discharge requires a multidisciplinary approach to deal with multiple potential problems. Regular monitoring based on anthropometry and biochemical markers is needed to guide the nutritional intervention.

Role of zinc in neonatal growth and brain growth: review and scoping review

This manuscript includes (1) a narrative review of Zinc as an essential nutrient for fetal and neonatal growth and brain growth and development and (2) a scoping review of studies assessing the effects of Zinc supplementation on survival, growth, brain growth, and neurodevelopment in neonates. Very preterm infants and small for gestational age infants are at risk for Zinc deficiency. Zinc deficiency can cause several complications including periorificial lesions, delayed wound healing, hair loss, diarrhea, immune deficiency, growth failure with stunting, and brain atrophy and dysfunction. Zinc is considered essential for oligodendrogenesis, neurogenesis, neuronal differentiation, white matter growth, and multiple biological and physiological roles in neurobiology. Data support the possibility that the critical period of Zinc delivery for brain growth in the mouse starts at 18 days of a 20-21-day pregnancy and extends during lactation and in human may start at 26 weeks of gestation and extend until at least 44 weeks of postmenstrual age. Studies are needed to better elucidate Zinc requirement in extremely low gestational age neonates to minimize morbidity, optimize growth, and brain growth, prevent periventricular leukomalacia and optimize neurodevelopment. IMPACT: Zinc is essential for growth and brain growth and development. In the USA, very preterm small for gestational age infants are at risk for Zinc deficiency. Data support the possibility that the critical period of Zinc delivery for brain growth in the mouse starts at 18 days of a 20-21-day pregnancy and extends during lactation and in human may start at 26 weeks' gestation and extend until at least 44 weeks of postmenstrual age. Several randomized trials of Zinc supplementation in neonates have shown improvement in growth when using high enough dose, for long duration in patients likely to or proven to have a Zinc deficiency. Studies are needed to better elucidate Zinc requirement in extremely low gestational age neonates to minimize morbidity, optimize growth and brain growth, prevent periventricular leukomalacia and optimize neurodevelopment.

Enteral zinc supplementation for prevention of morbidity and mortality in preterm neonates

BACKGROUND

Preterm and low birth weight infants are born with low stores in zinc, which is a vital trace element for growth, cell differentiation and immune function. Preterm infants are at risk of zinc deficiency during the postnatal period of rapid growth. Systematic reviews in the older paediatric population have previously shown that zinc supplementation potentially improves growth and positively influences the course of infectious diseases. In paediatric reviews, the effect of zinc supplementation was most pronounced in those with low nutritional status, which is why the intervention could also benefit preterm infants typically born with low zinc stores and decreased immunity.

OBJECTIVES

To determine whether enteral zinc supplementation, compared with placebo or no supplementation, affects important outcomes in preterm infants, including death, neurodevelopment, common morbidities and growth.

SEARCH METHODS

Our searches are up-to-date to 20 February 2020. For the first search, we used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 8), MEDLINE via PubMed (1966 to 29 September 2017), Embase (1980 to 29 September 2017), and CINAHL (1982 to 29 September 2017). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs. We ran an updated search from 1 January 2017 to 20 February 2020 in the following databases: CENTRAL via CRS Web, MEDLINE via Ovid, and CINAHL via EBSCOhost.

SELECTION CRITERIA

We included RCTs and quasi-RCTs that compared enteral zinc supplementation versus placebo or no supplementation in preterm infants (gestational age < 37 weeks), and low birth weight babies (birth weight < 2500 grams), at any time during their hospital admission after birth. We included zinc supplementation in any formulation, regimen, or dose administered via the enteral route. We excluded infants who underwent gastrointestinal (GI) surgery during their initial hospital stay, or had a GI malformation or another condition accompanied by abnormal losses of GI juices, which contain high levels of zinc (including, but not limited to, stomas, fistulas, and malabsorptive diarrhoea).

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal. Two review authors separately screened abstracts, evaluated trial quality and extracted data. We synthesised effect estimates using risk ratios (RR), risk differences (RD), and standardised mean differences (SMD). Our primary outcomes of interest were all-cause mortality and neurodevelopmental disability. We used the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

We included five trials with a total of 482 preterm infants; there was one ongoing trial. The five included trials were generally small, but of good methodological quality. Enteral zinc supplementation compared to no zinc supplementation Enteral zinc supplementation started in hospitalised preterm infants may decrease all-cause mortality (between start of intervention and end of follow-up period) (RR 0.55, 95% CI 0.31 to 0.97; 3 studies, 345 infants; low-certainty evidence). No data were available on long-term neurodevelopmental outcomes at 18 to 24 months of (post-term) age. Enteral zinc supplementation may have little or no effect on common morbidities such as bronchopulmonary dysplasia (RR 0.66, 95% CI 0.31 to 1.40, 1 study, 193 infants; low-certainty evidence), retinopathy of prematurity (RR 0.14, 95% CI 0.01 to 2.70, 1 study, 193 infants; low-certainty evidence), bacterial sepsis (RR 1.11, 95% CI 0.60 to 2.04, 2 studies, 293 infants; moderate-certainty evidence), or necrotising enterocolitis (RR 0.08, 95% CI 0.00 to 1.33, 1 study, 193 infants; low-certainty evidence). The intervention probably improves weight gain (SMD 0.46, 95% CI 0.28 to 0.64; 5 studies, 481 infants; moderate-certainty evidence); and may slightly improve linear growth (SMD 0.75, 95% CI 0.36 to 1.14, 3 studies, 289 infants; low-certainty evidence), but may have little or no effect on head growth (SMD 0.21, 95% CI -0.02 to 0.44, 3 studies, 289 infants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Enteral supplementation of zinc in preterm infants compared to no supplementation or placebo may moderately decrease mortality and probably improve short-term weight gain and linear growth, but may have little or no effect on common morbidities of prematurity. There are no data to assess the effect of zinc supplementation on long-term neurodevelopment.

Heavy Metals and Pesticides Toxicity in Agricultural Soil and Plants: Ecological Risks and Human Health Implications

Environmental problems have always received immense attention from scientists. Toxicants pollution is a critical environmental concern that has posed serious threats to human health and agricultural production. Heavy metals and pesticides are top of the list of environmental toxicants endangering nature. This review focuses on the toxic effect of heavy metals (cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn)) and pesticides (insecticides, herbicides, and fungicides) adversely influencing the agricultural ecosystem (plant and soil) and human health. Furthermore, heavy metals accumulation and pesticide residues in soils and plants have been discussed in detail. In addition, the characteristics of contaminated soil and plant physiological parameters have been reviewed. Moreover, human diseases caused by exposure to heavy metals and pesticides were also reported. The bioaccumulation, mechanism of action, and transmission pathways of both heavy metals and pesticides are emphasized. In addition, the bioavailability in soil and plant uptake of these contaminants has also been considered. Meanwhile, the synergistic and antagonistic interactions between heavy metals and pesticides and their combined toxic effects have been discussed. Previous relevant studies are included to cover all aspects of this review. The information in this review provides deep insights into the understanding of environmental toxicants and their hazardous effects.

Association Between Low Zinc Levels and Severity of Acute Respiratory Distress Syndrome by New Coronavirus SARS-CoV-2

BACKGROUND

We verify the prevalence of low zinc levels among critically ill patients infected by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in the intensive care unit (ICU) who required invasive mechanical ventilation, as well as its association with severity of acute respiratory distress syndrome (ARDS).

METHODS

This is an observational study composed of patients admitted to the ICU. Demographics, anthropometric data for calculating body mass index (BMI), and laboratory data were obtained at admission: blood count, ferritin, arterial blood gas, serum zinc levels, and C-reactive protein. Also, arterial oxygen tension (PaO₂ ) divided by fractional inspired oxygen (FiO₂ ) was calculated by the first arterial blood gas after intubation. A diagnosis of severe ARDS was determined if the PaO₂ /FiO₂ ratio was ≤100 mm Hg. Low zinc levels were established if zinc levels were <70 μg/dL.

RESULTS

A total of 269 patients met inclusion criteria; 51.3% were men; median age was 74 (66-81) years; 91.1% (245 of 269) were elderly. The median BMI was 30.1 (24.7-32.1) kg/m² , with 59.9% (161 of 269) of patients having overweight and obesity. The prevalence of low zinc levels was 79.6% (214 of 269) and severe ARDS was 56.5% (152 of 269). There was an association of low zinc levels and severe ARDS (odds ratio [OR], 14.4; 95% CI, 6.2-33.5; P < .001), even after adjusting for baseline variables (OR, 15.4; 95% CI, 6.5-36.3; P < .001).

CONCLUSION

Critically ill patients infected by SARS-CoV-2 with severe ARDS have a high prevalence of low serum zinc levels.

Zinc deficiency limiting head growth to discharge in extremely low gestational age infants with insufficient linear growth: a cohort study

OBJECTIVE

To assess the relationship of size for age with zinc deficiency in extremely low gestational age (GA) infants (23-28 weeks, ELGANs) who had insufficient linear growth despite optimizing other nutrients and to analyze changes in fronto-occipital circumference (FOC), weight and length with zinc supplementation.

STUDY DESIGN

Retrospective cohort study.

RESULTS

Among 302 ELGANs, a serum zinc concentration was obtained in 52 with insufficient linear growth (17%). Zinc deficiency (serum concentration <0.74 mcg/ml) was diagnosed in 8 of 24 (33%) small for GA (SGA) compared to 35 of 278 (13%) non-SGA infants (P = 0.01). Zinc supplementation for >2 weeks improved FOC growth to discharge or 50 weeks postmenstrual age in infants with Zn deficiency. However, neither linear growth nor weight gain improved with Zn supplementation.

CONCLUSION

Zinc deficiency was diagnosed in 14% ELGANs in this cohort. Zinc supplementation for >2 weeks improved FOC growth but not linear growth or weight gain.

Subchronic continuous inhalation exposure to zinc oxide nanoparticles induces pulmonary cell response in mice

OBJECTIVES

We used mice as an animal model to investigate the entry of ZnO nanoparticles from the ambient air into the lungs and other organs, subsequent changes in Zn levels and the impact on the transcription of Zn homeostasis-related genes in the lungs.

METHODS

The mice were exposed to two concentrations of ZnO nanoparticles; lower (6.46 × 104 particles/cm3) and higher (1.93 × 106 particles/cm3), allowed to breathe the nanoparticles in the air for 12 weeks and subjected to necropsy. Characterization of the ZnO nanoparticles was done using transmission electron microscopy (TEM). Energy-dispersive X-ray (EDX) spectroscopy was used to quantify ZnO nanoparticles in the lungs, brain, liver and kidney. The total zinc content in the lungs, brain, liver, kidney, red blood cells and plasma was estimated by inductively coupled plasma mass spectroscopy (ICP-MS). Transcription rate of the genes was evaluated by RealTime PCR.

RESULTS

The two concentration of ZnO nanoparticles in the ambient air produced two different outcomes. The lower concentration resulted in significant increases in Zn content of the liver while the higher concentration significantly increased Zn in the lungs (p < 0.05). Additionally, at the lower concentration, Zn content was found to be lower in brain tissue (p < 0.05). Using TEM/EDX we detected ZnO nanoparticles inside the cells in the lungs, kidney and liver. Inhaling ZnO NP at the higher concentration increased the levels of mRNA of the following genes in the lungs: Mt2 (2.56 fold), Slc30a1 (1.52 fold) and Slc30a5 (2.34 fold). At the lower ZnO nanoparticle concentration, only Slc30a7 mRNA levels in the lungs were up (1.74 fold). Thus the two air concentrations of ZnO nanoparticles produced distinct effects on the expression of the Zn-homeostasis related genes.

CONCLUSION

Until adverse health effects of ZnO nanoparticles deposited in organs such as lungs are further investigated and/or ruled out, the exposure to ZnO nanoparticles in aerosols should be avoided or minimised.

Lactobacillus plantarum IS-10506 supplementation increases faecal sIgA and immune response in children younger than two years

The immature intestinal immune system in young children develops as it comes into contact with dietary and microbial antigens in the gut. Intestinal microbiota plays a significant role in host defence mechanisms as shown by inflammatory responses towards potential pathogens. We investigated the probiotic function of Lactobacillus plantarum IS-10506 of 'dadih' origin in modulating immune response in young children. We aimed to assess its effect on their immune response by assessing transforming growth factor-β1 (TGF-β1) and tumour necrosis factor-α (TNF-α) responses and faecal secretory immunoglobulin A (sIgA) titre in a randomised, double-blinded placebo-controlled trial in 12-24-month-old children (n=38). We used four treatment groups for a 90-day supplementation period: placebo (n=11), probiotic (n=9), zinc (n=8) and probiotic and zinc (n=10). Faecal sIgA, plasma TGF-β1 and TNF-α titre were evaluated using the enzyme-linked immunosorbent assay standard technique. Statistical analysis divided the results (pre/post treatment) into high (>1) and low (<1) ratios. The results showed that faecal sIgA titre increased in all treatment groups compared with the control (placebo) and significantly increased in the probiotic group (P=0.05). In addition, the TGF-β1 ratio in the zinc group was significantly higher (P=0.05) than that in the placebo group. We observed a significant positive correlation between TGF-β1/TNF-α and faecal sIgA (r=0.27, P=0.04). Post hoc test results revealed that zinc supplementation has a significant effect on body-weight gain. Taken together, probiotic L. plantarum IS-10506 supplementation stimulates TGF-β1, which in turn increases the production of sIgA, in line with the significant correlation between TGF-β1/TNF-α and faecal sIgA.

Nutrition Management of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) is one of the most significant causes of morbidity and mortality among premature infants. The exact cause is considered multifactorial and related to gastrointestinal immaturity, inflammation and enteral feeding. The role of nutrition is vitally important in NEC. The main modifiable risk factor is the introduction and advancement of enteral feedings. After an infant has recovered from NEC, enteral feeds should be cautiously resumed to prevent injury from prolonged use of parenteral nutrition. The logistics of how, when, and what to feed are somewhat unclear and often depend on the severity of the disease. For patients with an enterostomy, refeeding the distal intestine with the small-intestinal ostomy output may improve bowel growth and prevent long-term complications.

Challenges in breast milk fortification for preterm infants

PURPOSE OF REVIEW

To outline new evidence published from 2013 to 2014 about breast milk fortification in preterm infants.

RECENT FINDINGS

Breast milk is the feeding choice for preterm infants because of its immunoprotective properties. However, breast milk's nutrient content is not sufficient for preterm infants, and interindividual variation is high. The variation challenges standard fortification, which assumes a standard breast milk composition. Two new fortification strategies (adjustable fortification and target fortification) optimize macronutrient intake and improve growth. Adjustable fortification uses blood urea nitrogen levels to adjust fortifier strength. Target fortification analyzes breast milk and fortifies macronutrients individually to achieve targeted intake. Its feasibility is shown in clinical routine. Current breast milk analyzers used for target fortification achieve acceptable precision for protein and fat but not for lactose and energy. Evidence of benefits for postdischarge breast milk fortification is lacking. Eliminating cow's milk products and feeding exclusively breast milk may decrease the occurrence of feeding intolerance and necrotizing enterocolitis. To facilitate exclusively breast milk diets, a collaboration of prenatal, nutrition and lactation stakeholders is key. Fortification increases osmolality; however, safety cutoffs to prevent necrotizing enterocolitis are unclear. There is also new evidence that composition and structure of various macronutrients and micronutrients affect growth and development, and might play a role in future fortification concepts.

SUMMARY

Recent research focuses on the variability of breast milk composition, its impact on postnatal growth patterns and the usefulness of target fortification. As well, diets exclusively composed of human milk are a promising approach to improve feeding tolerance. For safe fortification, osmolality cutoff levels are needed.

The Impact of Neonatal Illness on Nutritional Requirements-One Size Does Not Fit All

Sick neonates are at high risk for growth failure and poorer neurodevelopment than their healthy counterparts. The etiology of postnatal growth failure in sick infants is likely multi-factorial and includes undernutrition due to the difficulty of feeding them during their illness and instability. Illness also itself induces fundamental changes in cellular metabolism that appear to significantly alter nutritional demand and nutrient handling. Inflammation and physiologic stress play a large role in inducing the catabolic state characteristic of the critically ill newborn infant. Inflammatory and stress responses are critical short-term adaptations to promote survival, but are not conducive to promoting long-term growth and development. Conditions such as sepsis, surgery, necrotizing enterocolitis, chronic lung disease and intrauterine growth restriction and their treatments are characterized by altered energy, protein and micronutrient metabolism that result in nutritional requirements that are different from those of the healthy, growing term or preterm infant.

Zinc deficiency and toxicity in pediatric practice

PURPOSE OF REVIEW

Zinc is a commonly overlooked deficiency in developed countries, occurring in infants, children, and adolescents during critical growth periods. The purpose of this review is to present the evidence of zinc deficiencies and toxicities as well as treatment in pediatrics.

RECENT FINDINGS

During the last decade, the significance of zinc deficiency in childhood growth, morbidity, and mortality has been recognized by a number of large-scale supplementation trials in underdeveloped countries. Recognition of the recent nationwide shortage of injectable zinc available for total parenteral nutrition supplementation over the last 2 years focused attention on the possibility of zinc deficiency in the United States.

SUMMARY

Although primarily thought of as a problem reserved for underdeveloped countries, zinc deficiency has increasing pediatric prevalence in the USA. Zinc is an essential trace element in the body that is responsible for numerous structural, catalytic, and biochemical functions. Deficiencies can occur because of poor dietary intake, long-term parenteral nutrition without supplementation, and enteral causes such as malabsorption. Zinc deficiency is closely associated with stunting, respiratory infections, diarrhea, and dermatitis. Deficiency is hard to define solely by the serum levels. Clinicians should utilize a combination of serum zinc levels, presenting signs and symptoms, and nutritional intake via oral, enteral, and parenteral routes to accurately assess the deficiency risk and diagnosis.