Patient-derived iPSCs show premature neural differentiation and neuron type-specific phenotypes relevant to neurodevelopment

Ras/MAPK pathway signaling is a major participant in neurodevelopment, and evidence suggests that BRAF, a key Ras signal mediator, influences human behavior. We studied the role of the mutation BRAFQ257R, the most common cause of cardiofaciocutaneous syndrome (CFC), in an induced pluripotent stem cell (iPSC)-derived model of human neurodevelopment. In iPSC-derived neuronal cultures from CFC subjects, we observed decreased p-AKT and p-ERK1/2 compared to controls, as well as a depleted neural progenitor pool and rapid neuronal maturation. Pharmacological PI3K/AKT pathway manipulation recapitulated cellular phenotypes in control cells and attenuated them in CFC cells. CFC cultures displayed altered cellular subtype ratios and increased intrinsic excitability. Moreover, in CFC cells, Ras/MAPK pathway activation and morphological abnormalities exhibited cell subtype-specific differences. Our results highlight the importance of exploring specific cellular subtypes and of using iPSC models to reveal relevant human-specific neurodevelopmental events.

Serum and Hair Mineral Levels in Children with Failure to Thrive According to the Type of Feeding Difficulties

This study evaluated serum and hair mineral and trace element levels as well as levels of other nutritional factors affecting growth and appetite in young children with non-organic failure to thrive (NOFTT) based on the presence or types of feeding difficulty (FD). Between August 2012 and July 2015, 136 children less than 6 years of age with NOFTT were included. FD was diagnosed based on Wolfson criteria and divided into subtypes according to Chatoor's classification. Clinical data were reviewed, and serum and hair mineral levels were measured. Of all assessed serum and hair minerals, only hair sulfur contents differed significantly between subjects with and without infantile anorexia (39,392 ± 2211 vs. 40,332 ± 2551 μg/g, P = 0.034). There were no differences in serum and hair mineral levels between children with and without sensory food aversion. Hair copper contents were significantly lower in children with FD of reciprocity (12.3 ± 6.0 vs. 22.4 ± 25.1 μg/g, P = 0.049). While hair zinc contents were also lower, the difference was not statistically significant (49.2 ± 26.8 vs. 70.6 ± 41.0 μg/g, P = 0.055). Only hair manganese contents were significantly lower in children with posttraumatic FD (0.12 ± 0.04 vs. 0.26 ± 0.73 μg/g, P = 0.037). In conclusion, there were no differences in most serum and hair mineral levels in children with NOFTT, except for relatively lower hair levels of sulfur, copper and possibly zinc, and manganese in infantile anorexia, reciprocity, and posttraumatic types of FD, respectively.

Rasopathies - dysmorphic syndromes with short stature and risk of malignancy

OBJECTIVES

The term ´Rasopathies´ represents a group of five neurodevelopmental syndromes (Noonan, LEOPARD, Costello, Cardio-facio-cutaneous, and Neurofibromatose-Noonan syndrome) caused by germline mutation in genes encoding proteins involved in RAS/MAPK (rat sarcoma/mitogen-activated protein kinase) signaling pathway. The RAS/MAPK signaling pathway participates in regulation of cell determination, proliferation, differentiation, migration, and senescence and dysregulation of this pathway can lead to the risk of tumorigenesis. In this review, we aim to summarize the current clinical and molecular genetic knowledge on Rasopathies with special attention for the risk of cancer. We propose also clinical and therapeutic approach for patients with malignancy.

METHODS

We are reviewing the clinical and molecular basis of Rasopathies based on recent studies, clinical examination, and molecular diagnostics (mutation analysis of causal genes for Rasopathies) in Slovak pediatric patients.

RESULTS

Some clinical features, such as short stature, a specific facial dysmorphology and cardiac abnormalities are common to all of Rasopathy syndromes. However, there are unique signs by which the syndromes can differ from each other, especially multiple lentigo in LEOPARD syndrome, increased risk of malignancy in Costello syndrome, dry hyperkeratotic skin in patients with cardio-facio-cutaneous syndrome, and neurofibromas and cafe-au-lait spots in neurofibromatosis-Noonan syndrome.

CONCLUSION

Despite the overlapping clinical features, Rasopathy syndromes exhibit unique fenotypical features and the precise molecular diagnostics may lead to confirmation of each syndrome. The molecular diagnostics may allow the detection of pathogenic mutation associated with tumorigenesis.

Late vitamin K deficiency bleeding leading to a diagnosis of cystic fibrosis: a case report

Vitamin K deficiency bleeding (VKDB) in infants still occurs despite worldwide use of prophylaxis. Clinical manifestations can be dramatic with over 50% of patients presenting with intracranial haemorrhage and a mortality rate of 20% in late vitamin K deficiency bleeding. Special attention should be given to infants with a high risk profile (preterm, breast feeding, cholestasis, malabsorption). A tentative diagnosis can be made observing quick normalisation of some easy-to-perform haemostatic parameters (PT, aPTT) after administration of vitamin K. Nowadays, VKDB can still be the first clinical sign of diseases causing malabsorption of fat-soluble vitamins. In this case report, VKDB led to the diagnosis of cystic fibrosis, the most common fatal autosomal recessive disease among Caucasian people.

Mutational and functional analysis in human Ras/MAP kinase genetic syndromes

The Ras/mitogen-activated protein kinase (MAPK) pathway is essential in regulation of the cell cycle, cell differentiation, growth, and cell senescence, each of which are critical to normal development. A class of developmental disorders, the "RASopathies," is caused by germline mutations in genes that encode protein components of the Ras/MAPK pathway which result in dysregulation of the pathway and profound deleterious effects on development. One of these syndromes, cardiofaciocutaneous (CFC) syndrome, is caused by germline mutations in BRAF, MAP2K1 (MEK1) and MAP2K2 (MEK2), and possibly KRAS genes. Here, we describe the laboratory protocols and methods that we used to identify mutations in BRAF and MEK1/2 genes as causative for CFC syndrome. In addition, we present the techniques used to determine the effect these mutations have on activity of the Ras/MAPK pathway through Western blot analysis of the phosphorylation of endogenous ERK1/2, as well as through the use of an in vitro kinase assay that measures the phosphorylation of Elk-1.

Inhibition of milk ingestion and growth after administration of a neutral cannabinoid CB1 receptor antagonist on the first postnatal day in the mouse

We have shown previously that neonatal exposure to the cannabinoid CB1 receptor antagonist/inverse agonist rimonabant (SR141716) interfered with suckling and development. However, it was not clear whether the developmental deficiencies were induced by neutral CB1 receptor blockade, thereby inhibiting endogenous cannabinoid "tone," or by inverse agonist reduction of constitutive CB1 receptors. CB1 receptor blockade supports our hypothesis that low CB1 receptor concentrations and/or reduced endocannabinoid levels underlie infant nonorganic failure to thrive (NOFTT). Inverse agonism implies that lower constitutive CB1 receptor activity may be responsible for impaired food intake in newborns. In the present study, we injected the neutral CB1 receptor antagonist 5-(4-chlorophenyl)-3-[(E)-2-cyclohexylethenyl]-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole (VCHSR1) to 1-d-old mouse pups and recorded weight gain, gastric milk contents (milkbands), axillary temperature, and survival between age 1 and 10 d. The results showed a dose-related interference with all measures. These data show that (1) growth failure induced by rimonabant is generalized to another CB1 antagonist and (2) cannabinoid CB1 receptor activation by endocannabinoids is essential for normal milk ingestion and development in mice. This supports our hypothesis that endocannabinoid deficiency and perhaps CB1 receptor dysfunction represents the uncharacterized biologic vulnerability, which underlies NOFTT.

Evidence for impaired insulin production and higher sensitivity in stunted children living in slums

The objective of the present study was to investigate the changes in glucose and insulin metabolism in nutritionally stunted children that can be involved in the appearance of chronic diseases in adulthood. For this purpose, sixty-one children were selected, thirty-five boys and twenty-six girls, residents of slums in São Paulo, Brazil. The children were classified according to the height-for-age as stunted (<or=-1.5 Z-score; n 21) or non-stunted (>-1.5 Z-score; n 40). The glucose and insulin plasma levels were determined and, from these values, the indexes that evaluate the pancreatic beta-cell function (homeostasis model assessment (HOMA-B)) and insulin sensitivity (HOMA-S) were assessed. Stunted children showed lower values of fasting insulin than those of the non-stunted group (boys: 29.7 (SD 14.9) v. 50.4 (SD 29.2) pmol/l, P=0.019; girls: 34.4 (SD 12.6) v. 62.3 (SD 28.7) pmol/l, P=0.016) but the glucose levels were similar (boys: 4.6 (SD 0.3) v. 4.5 (SD 0.3) mmol/l; girls: 4.2 (SD 0.3) v. 4.4 (SD 0.3) mmol/l). Stunted children showed lower HOMA-B values (boys: 83 (SD 22) % v. 115 (SD 36) %, P=0.011; girls: 107 (SD 23) % v. 144 (SD 46) %, P=0.045) and higher HOMA-S values (boys: 196 (SD 92) % v. 120 (SD 62) %, P=0.014; girls: 159 (SD 67) % v. 98 (SD 57) %, P=0.016). The results show a decreased activity of beta-cell function and increased insulin sensitivity in stunted children. The decreased beta-cell function of this group may strongly predict type 2 diabetes.

[Growth failure in a boy with Klinefelter syndrome and IUGR]

BACKGROUND

Children born with a history of Intra-Uterine Growth Retardation (IUGR) may be susceptible for reduced growth velocity and growth deficiency. The causes of GH/IGF-1 resistance are unknown. Klinefelter syndrome is characterized by excessive growth, resulting from hypogonadism, open bone age and a prolonged growth.

OBJECTIVES

The case of a 6-year-old boy with Klinefelter syndrome born with IUGR and deep growth deficiency was studied.

A CASE REPORT

A 6-year-old boy with birth weight 2300 g born of term in 38 Hbd is presented. The cariotype was 47XXY. The phenotype was typical for a child with IUGR. GH in the clonidin test was 37.4 microIU/ml, IGF-1 -- 111 ng/ml. Increased IGF-1 level from 178.1 ng/ml to 360.9 ng/ml was founded in the IGF-1 generation test.

CONCLUSIONS

The cause of growth deficiency in this case could be GH/IGF-1 resistance.

Ophthalmic manifestations of congenital disorder of glycosylation type 1a

PURPOSE

To present the ophthalmic manifestations of patients with congenital disorder of glycosylation type Ia (CDG-Ia) due to the frequent R141H/F119L PMM2 genotype.

METHODS

Ophthalmic records of 23 patients (age: 10 months to 20 years) were evaluated. They had had at least one ophthalmic reexamination.

RESULTS

Measurements of refractive error showed that 18 patients were myopic, two were hypermetropic, and three could not be measured. Serial measurements in 12 patients indicated a progression towards myopia of 0.80 diopters (D) per year. Congenital esotropia and delayed visual maturation (DVM) were consistent findings. Two children developed good visual acuity (VA), 16 had low vision, and five were legally blind. Pallor of the optic disc was noted in five patients. Electroretinography (ERG) performed in nine patients showed reduced rod responses, while cone responses were only slightly reduced.

CONCLUSIONS

The present study illustrates the difficulties in examining severely disabled children. Consistent ophthalmic manifestations of CDG-Ia patients due to the R141H/F119L genotype were congenital esotropia, DVM, and a reduced rod response in ERG-examined patients. The vast majority of patients had reduced VA and developed myopia. We speculate that there is a relationship between the glycosylation defect in CDG-Ia and the development of myopia. We recommend that CDG-Ia patients be followed annually by an ophthalmologist.

Congenital disorder of glycosylation type Ia (CDG-Ia): phenotypic spectrum of the R141H/F119L genotype

AIMS

To delineate common and variable features and outcome of children with congenital disorder of glycosylation type Ia (CDG-Ia) caused by the frequent R141H/F119L PMM2 genotype.

METHODS

Clinical data on 25 patients (mean age 7.6 years, range 0-19) were analysed.

RESULTS

All patients had an early presentation with severe feeding problems and failure to thrive, hypotonia, hepatic dysfunction, inverted nipples, and abnormal subcutaneous fat pads. Eighteen patients were hospitalised in the neonatal period. Developmental delay was obvious before age 6 months. During the first seven months mean standard deviation score (SDS) for weight and length decreased 2.7 (SD = 2) and 2.4 (SD = 2), respectively. Mental retardation, ataxia, muscular atrophy, and febrile seizures were consistent features after infancy. Variable features included pericardial effusions, afebrile seizures, and stroke like episodes. Computed tomography/magnetic resonance imaging of the brain was normal in two patients examined before 4 months of age, but 18 children examined after 3 months of age had cerebellar atrophy, and 10 children also had supratentorial atrophy. Subsequent imaging showed progression of the cerebellar and supratentorial atrophy in eight and four of 10 children, respectively. Mean head circumference SDS declined from zero to -1.9 SD from age 3 months to 5 years. Motor ability ranged from none to walking with a rolator, and vocabulary ranged from none to comprehensible speech. The overall mortality ascribed to CDG-Ia was 18%.

CONCLUSION

Patients with the R141H/F119L genotype have an early uniform presentation including severe failure to thrive, but their functional outcome is variable. This genotype may well cause clinical manifestations in the severe end of the spectrum of CDG-Ia.

Distal renal tubular acidosis with severe hypokalaemia, probably caused by colonic H(+)-K(+)-ATPase deficiency

We describe a 21 month old male infant who presented with failure to thrive associated with severe hypokalaemia and metabolic acidosis, together with hypomagnesaemia. Evaluation revealed marked renal and probable faecal potassium wasting, distal renal tubular acidosis, mild urinary magnesium wasting, and a normal gastric pH (gastric H(+)-K(+)-ATPase). Hypokalaemic forms of metabolic acidosis, such as diabetic ketoacidosis and proximal renal tubular acidosis were ruled out from the clinical picture. The hypokalaemia of distal renal tubular acidosis usually improves with alkali therapy, but this was not observed: despite correction of acidosis with 5 mmol/kg potassium citrate per day, an additional 5 mmol/kg potassium chloride was required to bring serum potassium to 3.5 mmol/l. At 3 years of age potassium was provided in the absence of potential alkali and acidosis ensued; serum bicarbonate fell to 10 mmol/l. Although a specific genetic analysis is not yet possible, the abnormalities are consistent with a novel form of distal renal tubular acidosis. The pathophysiology probably does not stem from defects in the vacuolar H(+)-ATPase but more likely from deficient activity of the colonic isoform of H(+)-K(+)-ATPase that is resident in the medullary collecting duct and mediates potassium absorption and proton secretion.

Resting energy expenditure and prediction equations in young children with failure to thrive

OBJECTIVE

To compare predicted and measured resting energy expenditure (REE) in young children (birth to 3 years) with failure to thrive (FTT).

METHODS

REE (kcal/d) was measured by indirect calorimetry and compared with predicted REE from 3 sex and age group equations: World Health Organization (WHO), Schofield weight-based (SCH-WT), and Schofield weight- and height-based (SCH-WT-HT). The clinical characteristics associated with inaccuracy of predicted REE were examined.

RESULTS

Forty-five subjects (47% female) were evaluated. Their clinical characteristics (mean +/- SD) included age 1.2 +/- 0.7 years, length/height z score -2.1 +/- 1.3, weight z score -2.7 +/- 1.0, and measured REE 438 +/- 111 kcal/d. All prediction equations were within 10% accuracy <50% of the time. However, SCH-WT-HT did not significantly differ from measured REE (450 +/- 138 vs 438 +/- 111 kcal/d, P =.2) and was least likely to underestimate REE. Younger age and more severe growth failure (based on weight, length/height, or both) were associated with underestimation of REE by prediction equations.

CONCLUSION

REE should be measured in young infants and children with moderate to severe FTT when knowledge of caloric needs is required for optimal clinical care. The SCH-WT-HT equation was least likely to underestimate REE and is therefore preferred when REE cannot be measured in this group of children.

Metabolic stroke in isolated 3-methylcrotonyl-CoA carboxylase deficiency

A mildly retarded infant with failure to thrive developed hypoglycaemia, focal seizures, respiratory failure and hemiparesis during a febrile episode at the age of 16 months. A brain scan was initially normal and showed hemilateral focal edema and gliosis at later stages. 3-Methylcrotonyl-CoA carboxylase deficiency was suggested by elevated urinary excretion of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine, and confirmed by enzyme assays. The patient was treated with protein restriction and carnitine and remained stable during the following 5 years. Hemiparesis and some developmental delay persisted. In acute focal brain disease, metabolic disorders must be considered. 3-Methylcrotonyl-CoA carboxylase deficiency adds to the list of possible causes of "metabolic stroke".

Genetic analysis of the G4.5 gene in families with suspected Barth syndrome

Mutations have recently been identified in the G4.5 gene (Xq28), encoding the tafazzin protein, in patients with Barth syndrome. We performed mutational analysis in 5 families with suspected Barth syndrome. In 4 families a male child had all the cardinal features of this syndrome, and mutations of G4.5 were found in each case. A mutation was also found in a fifth family with an extensive history of early infant death from heart disease. The recognition of 5 unrelated families in 1 hospital during a 7-year period suggests that this disease may be underdiagnosed.

Infant growth and aorta total lipid fatty acids

Abnormal fetal and infant growth have increasingly been correlated with adult onset cardiovascular disease. To date, there is little known about the lipid fatty acid profiles in infant cardiovascular tissue. Therefore, we analysed total lipid fatty acids from thoracic and abdominal aorta intima and media from 24 normally grown sudden infant death syndrome cases. Aorta from small for gestational age (n = 2), failure to thrive from birth (n = 3), and premature (n = 1) infants were also examined. Dihomo-gamma-linolenic acid (C20:3n-6) and oleic acid (C18:1n-9) concentrations were significantly lower in the thoracic than in the abdominal aorta. Similar dietary related differences were found in the subgroup (n = 15) of infants fed on formula milks. Both abdominal and thoracic intimal arachidonic (C20:4n-6) to dihomo-gamma-linolenic acid ratios were greater in the infants with retarded growth after birth than in their normally grown counterparts. Growth restriction in infancy might disrupt the normal accretion of vascular endothelial polyunsaturated fatty acids.

Encephaloneuropathy with lysosomal zebra bodies and GM2 ganglioside storage

An 11-year-old girl died of a neuronal storage disorder that clinically was characterized by failure to thrive and muscular hypotonia from birth, with the subsequent evolution of motor neuron disease, epilepsy, and dementia. A wide range of metabolic disorders, including all forms of GM2 gangliosidosis, could be excluded. Electron microscopy demonstrated neuronal zebra body inclusions, and immunohistochemistry demonstrated that GM2 ganglioside was a major constituent of the storage material. We suggest that the patient died of a lysosomal storage disease that is clinically and biochemically different from Tay-Sachs disease, Sandhoff disease, and other GM2 gangliosidoses described previously. This case also further demonstrates that significant accumulation of GM2 ganglioside, which is crucial for dendritic formation, may occur in neuronal storage diseases lacking known defects in ganglioside catabolism.

[Pathogenesis and intensive care of infants with toxic-dystrophic syndrome]

Eighty-two children with the toxic dystrophic syndrome coursing in the presence of acute enteric infection were examined. A number of pathogenetically significant disorders were revealed: salt-deficient exsicosis, exsication, hypopotassemia, anemia, hypoproteinemia, stable metabolic acidosis, protein and energy insufficiency. Among the causes of protein and energy insufficiency associated with progressive weight loss the principal were impaired cavitary digestion, decrease of the absorption capacity of the intestine for proteins, fats, and carbohydrates, and long inadequate nutrition because of protracted diarrhea. Newly developed three-staged intensive care protocol with correction of homeostasis, provision with energy and nutrients, and repair of cavitary digestion and absorption capacity of the intestine helped reduce the mortality in this patient population from 13.4 to 4.8%.

Resting energy expenditure and body composition in pediatric HIV infection

One of the most striking features of HIV disease is the "wasting syndrome" or failure to thrive. Eighty percent of all perinatally HIV-infected children fail to grow normally. OBJECTIVE. Because severe malnutrition increases the morbidity of HIV infection and may shorten the already limited life expectancy of this population, we assessed resting energy needs, body composition, and nutrient intake in nine children perinatally HIV-infected, age 4 months to 4 years. DESIGN. Subjects were studied using measurements of resting energy expenditure (REE) by indirect calorimetry, body composition measurements by dual-energy X-ray absorptiometry (DEXA) and skinfolds, nutrient intake analysis by 24-hour recall, and serum protein levels. The HIV-infected children were free of secondary opportunistic infection at the time of the study. Subjects were reevaluated within the following year. RESULTS. REE correlated well (r = .856) with the predicted value from the World Health Organization (WHO) equation for basal energy expenditure. Measurement of percent body fat by skinfolds correlated well with DEXA percent body fat (r = .61). There was no significant difference between body fat assessed from skinfolds compared to published age-matched standards. All subjects met their recommended dietary allowance (RDA) for calories and protein. All subjects had adequate visceral protein stores for age. CONCLUSION. Perinatally infected children were not hypermetabolic when not secondarily infected and were able to maintain normal growth with the provision of adequate nutrition.

Resting energy expenditure in clinical pediatrics: measured versus prediction equations

OBJECTIVE

To evaluate the use of resting energy expenditure (REE) prediction equations compared with measured REE in children referred for REE to aid clinical care.

SUBJECTS

One hundred two patients, aged 0.2 to 20.5 years, 55% female, with a nutritional diagnosis of failure to thrive (76%), obesity (19%), or other (5%).

METHODS

We measured REE by indirect calorimetry and compared with prediction equations: Food and Agriculture/World Health Organization/United Nations University (FAO/WHO/UNU) equation, Harris-Benedict (H-B) equation, and two equations from Schofield, one using weight (SCHO-WT) and one using weight and height (SCHO-HTWT).

RESULTS

The SCHO-HTWT equation more closely predicted measured REE (100% +/- 19%), compared with the WHO equation (99% +/- 22%), the SCHO-WT equation, (99% +/- 21%), and the H-B equation (92% +/- 25%). The SCHO-HTWT equation was the best at predicting REE for obese subjects (95% +/- 17%), for those with failure to thrive (101% +/- 20%), and for children from birth to 3 years of age (101% +/- 23%). Nevertheless, the prediction equations closely predicted REE in only about 40% of subjects.

CONCLUSION

These findings suggest that the SCHO-HTWT equation predicts REE in children with clinical nutritional problems better than equations that use weight alone. In view of the wide variability in REE measurements, however, we believe that REE should be measured in patients for whom knowledge of caloric expenditure is required for clinical care.

Energy expenditure in congenital heart disease

Growth failure is a well recognised consequence of severe congenital heart disease. Total daily energy expenditure (TDEE) was investigated in eight infants with severe congenital heart disease to determine whether an increase in this parameter is an important factor in their failure to thrive, and to estimate the energy intake that would be required to allow normal growth. The infants were studied over a seven day period before surgery using the doubly labelled water method. Growth failure was evident; their mean age standardised body mass index was 80% of the expected value. Mean TDEE was 425 kJ/kg, significantly greater than in healthy infants (mean TDEE/kg SD score = +1.4; 95% confidence interval +0.27 to +2.57). In contrast, their energy intake was only 82% of the estimated average requirements. It was estimated that in early infancy a gross energy intake of 600 kJ/kg/day is required for normal growth in patients with congenital heart disease. This is unlikely to be achieved by energy supplements alone and early recourse to nasogastric feeding should be considered.

Increased energy expenditure in a patient with diencephalic syndrome

Total energy expenditure, measured in an infant with diencephalic syndrome with doubly labeled water, was 30% to 50% higher than that reported for other healthy infants whose energy expenditure was measured by the same technique and 13% higher than the patient's energy intake. This result suggests that the weight loss and cachexia of the diencephalic syndrome are the result of abnormally increased energy expenditure.

An atypical case of cytochrome c oxidase deficiency with biochemical heterogeneity in fibroblasts

A patient presenting in the first year of life with feeding difficulties and failure to grow had variable but persistent lactic acidemia noted at age 20 months. Nonspecific nutritional and biochemical therapy was accompanied by improvement in general clinical status, growth, gait, and development. However, she died in a catastrophic illness at the end of the third year of life. Studies in intact fibroblast mitochondria were consistent with an isolated but partial defect in cytochrome c oxidase. On direct assay of this enzyme complex in fibroblast homogenates and mitochondria, activity was much more severely depressed (less than or equal to 8% of control). Her fibroblasts normally synthesized the three cytochrome c oxidase subunits encoded on the mitochondrial genome. These data confirm that this patient had cytochrome c oxidase deficiency and demonstrate significant biochemical heterogeneity, since the results of the intact mitochondrial studies correlate better with her clinical course than do those of the direct enzymatic assays.

The effects of high-energy feeding on energy balance and growth in infants with congenital heart disease and failure to thrive

Failure to thrive (FTT) in infants with congenital heart disease (CHD) can be attributed to their low energy intakes and high resting energy expenditures. Energy intake, energy expenditure and growth were studied in infants with CHD on normal formula feeds and then on feeds supplemented with glucose polymer to see whether supplementation improved energy retention and growth. Mean gross energy intakes increased by 31.7% on high-energy feeding and mean weight gain improved from 1.3 g/kg per d on control to 5.8 g/kg per d on high-energy feeding. Resting oxygen consumption (VO2 ml/kg per min) was not significantly different on the two feeding regimens, although respiratory quotient rose on high-energy feeding reflecting the increased carbohydrate intake. Estimated energy costs of growth on high-energy feeding fell within the previously described range for normal infants. It is recommended that infants with CHD known to be associated with FTT are fed on high-energy diets from the time of diagnosis in order to optimize growth.

Vitamin B12 and folic acid absorption and hematological status in children with postenteritis enteropathy

In a group of nine children with postenteritis enteropathy (i.e., persisting small-intestinal mucosal damage and failure-to-thrive after an acute episode of gastroenteritis), absorption capacities for vitamin B12 and folic acid were studied and compared with hematological status in peripheral blood. The fractional absorptions of vitamin B12 (FAB12) and folic acid (FAFol) were determined by means of a double-isotope technique employing a single-stool-sample test. The children were examined when growth retardation was maximal, and examinations were repeated during the late recovery period. In spite of considerable small-intestinal mucosal damage, only the absorption of vitamin B12 was markedly affected, while that of folic acid was almost intact. When growth retardation was maximal, FAB12 was below the normal age-correlated range in half of the children. FAB12 was also severely reduced in all longitudinally observed children when compared with the results obtained during the late recovery period (p less than 0.005). FAFol was below the normal range in one fourth of the children, but the reduction was modest and insignificant when compared with the results of repeated examinations during the late recovery period. A moderate iron deficiency was detected in half the children. High levels of plasma vitamin B12, folic acid, and erythrocyte folate were detected at both early and later examinations, indicating that these parameters were not affected by the reduced absorption capacities. However, if malabsorption and chronic diarrhea are combined with low dietary intake of vitamin B12, as is the case for many children in the Third World, depletion of vitamin B12 stores may result.

Abnormal sweat electrolytes in a case of celiac disease and a case of psychosocial failure to thrive. Review of other reported causes

Sweat electrolytes were initially elevated in a child who was diagnosed as having celiac disease and also in one with psychosocial failure to thrive. Subsequent sweat tests were normal after nutritional status of the patients had improved with therapy. The reports of elevated sweat electrolytes in conditions other than cystic fibrosis are discussed. It is emphasized that sweat test methods other than the quantitative pilocarpine iontophoresis method are not reliable. The occurrence of false-positive sweat tests demonstrates the need for care in the interpretation of elevated sweat electrolytes and the necessity of performing repeat quantitative pilocarpine iontophoresis for the establishment of the diagnosis of CF. Celiac disease and malnutrition from other causes may cause sweat electrolytes to be elevated.

Environmental deprivation and transient elevation of sweat electrolytes

We report five children who had transient elevations in sweat electrolyte values in association with environmental deprivation. The high electrolyte values were not always associated with malnutrition, and normalized more rapidly than weight. The reason for these abnormalities is unknown. In as much as elevated sweat electrolytes are rarely associated with environmental deprivation, repeat studies are recommended before diagnosing cystic fibrosis in such children.

Follow-up studies on children with severe dietary chloride deficiency during infancy

Ten children who had severe dietary chloride deficiency during early infancy have grown normally during their first 4 to 5 years. With the exception of one child who did not get into the sitting position alone until he was 9 1/2 months of age, the patients reached the usual developmental milestones of the first 2 years during the expected age intervals. Developmental and psychological testing indicates that all of the children have at least average ability. However, three children have shown behavior patterns that may interfere with successful school performance. Serum creatinine and urea nitrogen concentrations appear to be normal as does renal concentrating capacity. During a 4-year follow-up, one child has shown persistent and a second intermittent microscopic hematuria.