Stratégie de prise en charge nutritionnelle de l'enfant et de l'adolescent (Nutrition orale, entérale, parentérale)

Children are especially threatened by malnutrition, because of the high protein-energy cost of growth. Any nutritional deficiency is the source of protein energy malnutrition, which compounds the problems of underlying disease. The protein-energy cost of catch-up growth is particularly high, and should lead to a rigorous adjustment of nutritional supply to prevent metabolic disorders associated with refeeding syndrome (directly related to the homeostatic change secondary to severe protein energy malnutrition). If the gastrointestinal tract can be used for refeeding, it should be used (oral or enteral nutrition). When the gastrointestinal tract is unable to meet the protein and energy requirements, parenteral nutrition is required. Catch-up growth may be achieved by using appropriate nutritional support.     

Stratégies de dépistage de la dénutrition chez l''enfant hospitalisé

Metabolic stress modifies homeostasis, therefore nutrient's metabolism and nutritional needs. Stress is a risk factor of malnutrition, which increases morbidity and short-term mortality, and, in the child, can threaten long-term growth. Nutritional assessment is difficult in critically ill children. Nutritional support must be undertaken early as possible, especially in malnourished children and with severe agression. Enteral nutrition must be privileged. Parenteral nutrition is indicated when enteral nutrition is impossible, badly supported or insufficient to satisfy needs. Monitoring must be rigorous because aggression increases the risk of metabolic complications.     

Aspects récents de la régulation hormonale de la lipoprotéine lipase adipocytaire

Lipoprotein lipase, an important enzyme in lipid and lipoprotein metabolism is synthetized, glycosylated and secreted by adipocytes. These processes are stimulated by:

-- Insulin, through a decrease in the adipocyte AMPc level.

-- Adenosine, probably by an increase in pro-LPL levels and glucose uptake.

-- Gastrine which is insulino-mimetic in this respect and has a common site of action with insulin.

-- Pancreozymin by a glucoindependent action on proenzyme synthesis.

The role of AMPc is important but it is not the exclusive messenger for these regulation processes: digestive hormone effects are not AMPc dependant and adenosine acts as a facilitating factor for insulin action.     

Évaluation de l'état nutritionnel et des besoins de l'enfant et de l'adolescent

Ten to fifteen percent of hospitalized children suffer from malnutrition. Children suffering from chronic diseases are at particularly high risk for malnutrition. A systematic screening for malnutrition and nutritional risk can improve nutritional care in this population. Simple measures (weight and height at admission) can be used to calculate nutritional indices (weight for height ratio or body mass index). Nutritional risk depends on: 1) the severety of the principal diagnosis, 2) the ability to feed oneself, and 3) the pain intensity. The oral or enteral route is preferred when the gut is functional. In all cases nutritional status must be followed throughout hospitalisation. Furthermore, it is preferable to begin nutritional care before malnutrition sets in. Nutritional care can improve the outcome and well-being of hospitalized children.     

Mécanismes de la dénutrition chez l'enfant et l'adolescent

Malnutrition in child and adolescent is observed in various situations where there is an imbalance between the food intakes and caloric and proteic needs. Child is particularly vulnerable because its reserves are weak and its high caloric and proteic needs because of its growth. Various mechanisms leading to malnutrition were brought back and correspond to distinct clinical entities. The situations of malnutrition by exclusive mechanism of intake deficiency meet primarily in third world where they can take the form of starvation, extreme adaptive situation with prolonged fast. During situations known as of aggression like severe sepsis, polytraumatism, extended burn, surgery, malnutrition can settle quickly. Mechanism brought back in situation of acute aggression is defined classically like related to hypermetabolism with hypercatabolism. Kwashiorkor, another type of caloric and proteic malnutrition concerning child in third world, cannot be regarded as a simple caloric and proteic deficiency. It currently seems that a deficiency at the same time in macronutriments and micronutriments plays a part in genesis of this pathology. The glutathion seems in particular, to play a fundamental part in the kwashiorkor's pathophysiology. The most documented hypothesis relates imbalance between production of free radicals and mechanisms of defence. Mechanisms of repair would be insufficient, and persistence of membrane deteriorations would cause anomalies observed in kwashiorkor like oedema, hepatic overload, neurological disorders and diarrhoea.     

Influence d'une supplémentation en vitamine E sur le sélénium au cours d'une nutrition parentérale exclusive chez l'enfant

Double supplementation in selenium and vitamin E during total parenteral nutrition (TPN) now appears essential to avoid clinical manifestations of their deficiencies. We studied children of 1 month to 12 years of age deficient in selenium (plasmatic selenium : P-Se : 40–80 μg/L) and vitamin E (ratio vitamin E on total lipids : VE/LT = 1.10 − 1.80 mg/g). Prior to supplementation, the ratio VE/LT is negatively correlated to P-Se (r = −0.81) and positively to erythrocyte selenium (RBC-Se, r = +0.64). These results suggest a balance between both. The parenteral alimentation was then supplemented with sodium selenite (3 μg/kg/d) and weekly with IM vitamin E (Protocol 1 : P1 : 30 to 60 mg according to age; Protocol 2 : P2 : twice these doses). The ratio VE/LT returned to normal faster in P2 than in P1 (P2 : 15–30 days; P1 : about 120 days). Selenium supplementation restores P-Se quickly (45–60 days) contrary to RBC-Se which is a slow process (120 d). High vitamin E intakes do not seem to have an effect upon selenium stores : no statistical differences were found between P1 and P2 during the same period. Such intakes may however be indicated during the first month of TPN to balance the time course for repletion of RBC-Se which is long (120 days).     

Complications hépatiques de la nutrition artificielle chez l'enfant : stratégies thérapeutiques

Parenteral nutrition-associated complications in children can result in the deterioration of hepatic structure and function which ultimately leads to cirrhosis. The frequency and prevalence of these complications are difficult to clarify; moreover, their presentation is polymorphous (lithiasis, steatosis, cholestasis, fibrosis) and nonspecific. Patients at risk need to be clearly identified, since preventive intervention and treatment can slow down the disease's progression. However, when intestinal functions become severely impaired with absolute dependency on parenteral nutrition, intestinal transplantation becomes the sole treatment.     

Stratégies de prise en charge nutritionnelle spécifiques : l'enfant en cancérologie

In children with cancer, malnutrition may antedate the diagnosis or be a result of aggressive chemotherapeutic regimens. The prevalence of malnutrition at diagnosis is related to the type of tumour and the extent of the disease, ranging from < 10% in patients with standard-risk acute lymphoblastic leukaemia to 50% in children with advanced neuroblastoma. The pathogenis of the energy imbalance that underlies the development of malnutrition is complex, including increased breakdown of fat and protein as well as energy-consumptive changes in carbohydrate metabolism (Cori cycle). Despite several confounding factors (different definitions of nutritional status and the wide variety of measures used for its assessment), studies have shown decreased tolerance of chemotherapy associated with altered metabolism of antineoplastic drugs, increased infection rates, altered quality of life and possibly poor clinical outcome in malnourished patients. In this article, we review guidelines for the nutritional management of a child with cancer and we purpose an algorithm for nutritional support.     

Biodisponibilité de la glutamine et réponse du métabolisme protéique à l'apport de glutamine chez l'homme

Glutamine is synthetized in most tissue and accounts for two-thirds of the free amino acid pool in skeletal muscle. Glutamine is not only an interorgan nitrogen shuttle but a precursor of urinary ammonium, and a favorite fuel of the immune system and the gut (which uses ≠ 17 g of glutamine per day). Because they were designed at a time when glutamine was considered both unstable and non-essential, « tradtionalparenteral nutrition (PN) solutions are devoid of glutamine. Although « classicPN is able to maintain normal rates of glutamine turnover in healthy subjects or unstressed patients, classic PN solutions are unable to correct the precipitous depletion of glutamine pool that accompagnies catabolic illness. Glutamine becomes a « conditionally essentialamino acid in these situations. Replenishment of glutamine pool seems to stimulate protein synthesis, and improve nitrogen balance in catabolic patients. Supplementation of PN with glutamine-containing dipeptides or α-ketoglutarate (at doses of 15–50 g/d) is as effective as glutamine itself. The enteral route represents an attractive alternative for the supply of glutamine since : 1) glutamine is efficiently absorbed ; 2) nearly 50 % of enterally infused glutamine reaches systemic blood ; 3) glutamine residues present in a bound form in peptides seem to be bioavailable ; and 4) in addition to its protein anabolic effect, glutamine affects intestinal absorption and trophicity.     

Éducation des familles et de l'enfant en nutrition artificielle à domicile

The techniques of artificial nutrition came of age since the seventies (1969 for enteral nutrition and 1973 for parenteral nutrition). Artificial nutrition has considerably modified the outcome of a great number of children with severe digestive tract pathologies or many other disorders making impossible or ineffective oral food administration. There are currently two techniques of artificial nutrition: enteral nutrition (the most physiological using the digestive tract) and parenteral nutrition (by central venous line, more demanding and more complications). Home parenteral and enteral nutrition emerged with new realities: increase in the number of children needing a nutritional assistance, increase in the number of indications and a constant need to make autonomous the child and the family leading to a better quality of life. The best care for these children needs a multidisciplinary approach (physicians, nurses, dieteticians, pharmacists, speech therapist, psychologists…) and a close relation between primary care and hospital. This also requires a significant investment of parents who are sometimes assisted by private nurses. Parents are thus educated with techniques of enteral nutrition and parenteral nutrition: use of the material, training with the care, learning the action to be taken in case of problem. They have thus a role of caregiver: heavy responsibility necessary to the return at home of their child. The educational role of the hospital team thus takes a paramount importance with the aim to provide an optimal home return and the most adequate care by the family.     

Nutrition parentérale prolongée chez l'enfant : utilisation de triglycérides à chaîne moyenne

Data concerning the long-term parenteral administration of medium chain triglycerides (MCT) to children are lacking. The goal of this study was to evaluate the effect and tolerance of a 50% LCT/MCT mixture. We studied 12 children (1,5–17 yrs old) who were on TPN for 6 months to 12 years. Cyclic TPN included 4 to 7 nocturnal infusions a week with mean daily intakes of 214 ± 92 mg/kg nitrogen and 47 ± 17 kcal/kg of non-protein energy, including 10 to 32% as lipid (Intralipid® 20%). At the start of the study all the patients were switched to receive a 50% MCT/LCT mixture (Bruneau®) at the same rhythm, amount and rate as before. The following parameters were studied at day 0 and after 1, 3 and 6 months : plasma lipid status including apolipoprotein A-I, A-II, B and essential fatty acids (EFA) (plasma and red blood cells) ; liver function tests, hemoglobin (Hb), platelets (Pt) fibrin (FI), proaccelerin (FV), plasma protein (PP) and bicarbonates (BIC). Twenty-four-hour urine samples were assessed for ketone bodies and dicarboxylic acids. No clinical signs of intolerance were observed ; there was no difference in triglycerides, cholesterol, phospholipid, apo B, EFA, liver function tests results excepts for gammaglutamyl transpeptidase (GGT) or Hb, Pt, FI, FV, PP and BIC. The main differences were a significant increase in apolipoprotein A at 1, 3 and 6 months and a decrease in GGT at the 6th month. Mild urinary excretion of adipic, suberic and sebacic acids appeared at the concentrations of 13.3 ± 5.2, 17.6 ± 11 and 44 ± 39 μmol/mmol creatinin respectively. These results show no clinical or biological side-effects together with a mild benefit concerning Apo A and GGT. Omega oxidation was moderately involved, as demonstrated by urinary dicarboxylic acid excretion ; a 50% reduction in EFA intake did not affect the EFA status of these pediatric patients.     

Quelques dérivés de l'amino-11 vinburnine à propriétés protectrices cérébrales

Quelques dérivés de l'amino-11 vinburnine (amides, aminoamides, urée, carbamates) sont préparés. Leurs propriétés protectrices contre l'œdème cérébral provoqué chez le rat par le triéthylétain sont évaluées.     

Conséquences de la dénutrition chez l'enfant et l'adolescent. Mortalité, morbidité, conséquences médicoéconomiques

In the developed countries, the sick children are at risk of protein-energy malnutrition (PEM). Marasmus is the most common form of severe PEM in such children. Its major characteristics are low muscle and fat masses with the presence of marked facial, axillary and inguinal skinfolds. Furthermore the marastic children are irritable and depressed. When the PEM is moderate, which is more frequent, the affected children present a failure to thrive. Severe and moderate PEM have multiple functional consequences on different systems and organs with an impact on mortality, morbidity and costs. In this paper, the functional consequences on the immune system, digestive tract, liver, lung, heart, kidney, skin, bone and brain are passed in review. To end, some comments are done about the particularities of PEM in mental anorexia and obesity.