Maingay-de Groof, F.

The branched-chain amino acid requerement in neonates (Doctoral Thesis)

2012-09-26T00:00:00Z

Growth during the earliest stages of life is an important determinant of an individual’s later health and risk of chronic disease. Substantial evidence shows that growth in the first 2 years of life, especially high early weight gain, is associated with adverse health outcomes later in life, including increased blood pressure, increased weight gain and body fat deposition and increased risk of diabetes. Higher protein intake for infants who are formula fed may play a role with these health outcomes because formula-fed children reach a higher body weight and weight for length at one year of age compared to those fed breast milk. A lower protein intake in infant formula is associated with lower weight up at 2 years of age which might be beneficial because the slower pattern of growth in breastfed infants might be protective for the development of the metabolic syndrome. In preterm infants, however, a higher protein intake in the first month of life correlates with improved neurodevelopment. Preterm infants have higher protein turnover rates and protein losses than terms and thereby higher protein requirements. Excessive intake of amino acids has been shown to reduce (brain) growth and to influence neurotransmitter concentrations in the brain of rats which might put the developing brain at risk. Inadequate amino acid intake impairs protein synthesis, which is pivotal for growth. The growth rate of the preterm infant should mimic at least the growth rate of the intrauterine fetus at the same gestational age. Achieving appropriate growth and nutrition accretion of preterm neonates is often difficult during hospitalization because of metabolic and gastrointestinal immaturity and other complicating medical conditions. Many preterm neonates require total parental nutrition for their initial nutritional support but this is associated with several complications, including the increased risk of infection, mucosal atrophy and cholestatic jaundice. Therefore, transition to full enteral feeding and the cessation of TPN are accomplished as soon as feasible and safe, taking in consideration that enteral feeding is associated with a detrimental morbidity like necrotising enterocolitis. Enteral nutrition can be initiated immediately after birth by introducing small amounts to enhance the development of the gastro-intestinal tract and for this reason is referred to as “trophic”, “priming” or “minimal enteral feeding”.

Lysine requirement of the enterally fed term infant in the first month of life (Article)

2011-12-01T00:00:00Z

Background: Infant nutrition has a major impact on child growth and functional development. Low and high intakes of protein or amino acids could have a detrimental effect. Objective: The objective of the study was to determine the lysine requirement of enterally fed term neonates by using the indicator amino acid oxidation (IAAO) method. L-[1-13C]phenylalanine was used as an indicator amino acid. Design: Twenty-one neonates were randomly assigned to lysine intakes that ranged from 15 to 240 mg·kg-1·d-1. Breath, urine, and blood samples were collected at baseline and during the plateau. The mean lysine requirement was determined by using biphasic linear regression crossover analysis on the fraction of13CO2recovery from L-[1-13C] phenylalanine oxidation (F13CO2) and phenylalanine oxidation rates calculated from the L-[1-13C]phenylalanine enrichment of urine and plasma. Results: The mean (±SD) phenylalanine flux calculated from urine and plasma L-[1-13C]phenylalanine enrichment data were 88.3 ± 6.9 and 84.5 ± 7.4 μmol·kg-1·h-1, respectively. Graded intakes of lysine had no effect on phenylalanine fluxes. The mean lysine requirement determined by F13CO2was 130 mg·kg-1·d-1(upper and lower CIs: 183.7 and 76.3 mg·kg-1·d-1, respectively). The mean requirement was identical to the requirement determined by using phenylalanine oxidation rates in urine and plasma. Conclusions: The mean lysine requirement of enterally fed term neonates was determined by using F13CO2and phenylalanine oxidation rates calculated from the L-[1-13C] phenylalanine enrichment of urine and plasma. These methods yielded a similar result of 130 mg lysine·kg-1·d-1. This study demonstrates that sampling of13CO2in expired air is sufficient to estimate the lysine requirement by using the IAAO method in infants. This trial was registered at www.trialregister.nl as NTR1610.

Plasma water as a diagnostic tool in the assessment of dehydration in children with acute gastroenteritis (Article)

2010-07-01T00:00:00Z

Acute gastroenteritis is common in childhood. The estimation of the degree of dehydration is essential for management of acute gastroenteritis. Plasma water was assessed as a diagnostic tool in children with acute gastroenteritis and dehydration admitted to hospital. In a prospective cohort study, 101 patients presenting at the emergency department with dehydration were included. Clinical assessment, routine laboratory tests, and plasma water measurement were performed. Plasma water was measured as a percentage of water content using dry weight method. During admission, patients were rehydrated in 12 h. Weight gain at the end of the rehydration period and 2 weeks thereafter was used to determine the percentage of weight loss as a gold standard for the severity of dehydration. Clinical assessment of dehydration was not significantly associated with the percentage of weight loss. Blood urea nitrogen (r∈=∈0.3, p∈=∈0.03), base excess (r∈=-0.31, p∈=∈0.03), and serum bicarbonate (r∈=∈0.32, p∈=∈0.02) were significantly correlated with the percentage of weight loss. Plasma water did not correlate with the percentage of weight loss. On the basis of the presented data, plasma water should not be used as a diagnostic tool in the assessment of dehydration in children with acute gastroenteritis.

Extensive cerebral infarction in the newborn due to incontinentia pigmenti (Article)

2008-07-01T00:00:00Z

Introduction: Incontinentia pigmenti (IP) is a rare X-linked dominant neuroectodermal multisystem disorder characterized by skin lesions following Blaschko lines. In almost all patients the skin is involved and in 30-50% the central nervous system (CNS) is. Vascular occlusive phenomena probably play a role in CNS involvement. Whether these vascular changes are based on macro- or microvascular disease in the neonatal presentation is not fully understood. Patients and methods: We describe two patients with IP with neonatal seizures related to cerebral infarction. In comparison, we reviewed reports of ischaemic cerebrovascular injury in neonatal IP. Results: No descriptions of documented large artery occlusion in neonatal IP was found in the literature. One of our patients showed striatal arteriopathy, never described before in IP. Extensive injury in one of our cases was heterogeneous, mixing healthy with diseased areas within large arterial fields. Conclusions: We postulate that neonatal cerebral infarction in IP is a macrovascular disorder of medium sized or small arteries. The pattern of arterial involvement might follow hypothetical brain Blaschko lines. The extent of cerebral involvement probably results from genetic mosaicism in which Lyonisation leads to endothelial apoptosis, similar to the process in the skin.

Acute stress response in children with meningococcal sepsis: important differences in the growth hormone/insulin-like growth factor I axis between nonsurvivors and survivors (Article)

2002-01-01T00:00:00Z

Septic shock is the most severe clinical manifestation of meningococcal disease and is predominantly seen in children under 5 yr of age. Very limited research has been performed to elucidate the alterations of the GH/IGF-I axis in critically ill children. We evaluated the GH/IGF-I axis and the levels of IGF-binding proteins (IGFBPs), IGFBP-3 protease, glucose, insulin, and cytokines in 27 children with severe septic shock due to meningococcal sepsis during the first 3 d after admission. The median age was 22 months (range, 4-185 months). Eight patients died. Nonsurvivors had extremely high GH levels that were significant different compared with mean GH levels in survivors during a 6-h GH profile (131 vs. 7 mU/liter; P < 0.01). Significant differences were found between nonsurvivors and survivors for the levels of total IGF-I (2.6 vs. 5.6 nmol/liter), free IGF-I (0.003 vs. 0.012 nmol/liter), IGFBP-1 (44.3 vs. 8.9 nmol/liter), IGFBP-3 protease activity (61 vs. 32%), IL-6 (1200 vs. 50 ng/ml), and TNFalpha (34 vs. 5.3 pg/ml; P < 0.01). The pediatric risk of mortality score correlated significantly with levels of IGFBP-1, IGFBP-3 protease activity, IL-6, and TNFalpha (r = +0.45 to +0.69) and with levels of total IGF-I and free IGF-I (r = -0.44 and -0.55, respectively). Follow-up after 48 h in survivors showed an increased number of GH peaks, increased free IGF-I and IGFBP-3 levels, and lower IGFBP-1 levels compared with admission values. GH levels and IGFBP-1 levels were extremely elevated in nonsurvivors, whereas total and free IGF-I levels were markedly decreased and were accompanied by high levels of the cytokines IL-6 and TNFalpha. These values were different from those for the survivors. Based on these findings and literature data a hypothetical model was constructed summarizing our current knowledge and understanding of the various mechanisms.