A study of the age of onset, diet and the importance of infection in the pattern of severe protein-energy malnutrition in Ibadan, Nigeria

Edematous severe acute malnutrition is characterized by hypomethylation of DNA

Edematous severe acute childhood malnutrition (edematous SAM or ESAM), which includes kwashiorkor, presents with more overt multi-organ dysfunction than non-edematous SAM (NESAM). Reduced concentrations and methyl-flux of methionine in 1-carbon metabolism have been reported in acute, but not recovered, ESAM, suggesting downstream DNA methylation changes could be relevant to differences in SAM pathogenesis. Here, we assess genome-wide DNA methylation in buccal cells of 309 SAM children using the 450 K microarray. Relative to NESAM, ESAM is characterized by multiple significantly hypomethylated loci, which is not observed among SAM-recovered adults. Gene expression and methylation show both positive and negative correlation, suggesting a complex transcriptional response to SAM. Hypomethylated loci link to disorders of nutrition and metabolism, including fatty liver and diabetes, and appear to be influenced by genetic variation. Our epigenetic findings provide a potential molecular link to reported aberrant 1-carbon metabolism in ESAM and support consideration of methyl-group supplementation in ESAM.

Standing on giant shoulders: a personal recollection of the lives and achievements of eminent animal scientists 1965–2015

This article is a compilation of pieces that are part biographical sketches and part personal recollections of 18 scientists with whom the author was acquainted in three continents over almost 50 years. The subjects, from Australia, the United States and the United Kingdom, will be recognisable to many in the field, especially more experienced scientists. For younger scientists, the article also is intended to put a human face on a generation of famous researchers who otherwise would be familiar only as somewhat anonymous authors of classic papers and reviews.

Severe childhood malnutrition

The main forms of childhood malnutrition occur predominantly in children <5 years of age living in low-income and middle-income countries and include stunting, wasting and kwashiorkor, of which severe wasting and kwashiorkor are commonly referred to as severe acute malnutrition. Here, we use the term 'severe malnutrition' to describe these conditions to better reflect the contributions of chronic poverty, poor living conditions with pervasive deficits in sanitation and hygiene, a high prevalence of infectious diseases and environmental insults, food insecurity, poor maternal and fetal nutritional status and suboptimal nutritional intake in infancy and early childhood. Children with severe malnutrition have an increased risk of serious illness and death, primarily from acute infectious diseases. International growth standards are used for the diagnosis of severe malnutrition and provide therapeutic end points. The early detection of severe wasting and kwashiorkor and outpatient therapy for these conditions using ready-to-use therapeutic foods form the cornerstone of modern therapy, and only a small percentage of children require inpatient care. However, the normalization of physiological and metabolic functions in children with malnutrition is challenging, and children remain at high risk of relapse and death. Further research is urgently needed to improve our understanding of the pathophysiology of severe malnutrition, especially the mechanisms causing kwashiorkor, and to develop new interventions for prevention and treatment.

Defining malnutrition: A plea to rethink

In a recent consensus report in Clinical Nutrition the undernourished category of malnutrition was proposed to be defined and diagnosed on the basis of a low BMI or unintentional weight loss combined with low BMI or FFMI with certain cut off points. The definition was endorsed by ESPEN despite recent endorsement of a very different definition. The approach aims to assess whether nutritional intake is sufficient but is imprecise because a low BMI does not always indicate malnutrition and individuals with increasing BMI's may have decreasing FFM's. The pathophysiology of individuals, considered to be malnourished in rich countries and in areas with endemic malnutrition, results predominantly from deficient nutrition combined with infection/inflammation. Both elements jointly determine body composition and function and consequently outcome of disease, trauma or treatment. When following the consensus statement only an imprecise estimate is acquired of nutritional intake without knowing the impact of inflammation. Most importantly, functional abilities are not assessed. Consequently it will remain uncertain how well the individual can overcome stressful events, what the causes are of dysfunction, how to set priorities for treatment and how to predict the effect of nutritional support. We therefore advise to consider the pathophysiology of malnourished individuals leading to inclusion of the following elements in the definition of malnutrition: a disordered nutritional state resulting from a combination of inflammation and a negative nutrient balance, leading to changes in body composition, function and outcome. A precise diagnosis of malnutrition should be based on assessment of these elements.

Social, dietary and clinical correlates of oedema in children with severe acute malnutrition: a cross-sectional study

BACKGROUND

Severe acute malnutrition is a serious public health problem, and a challenge to clinicians. Why some children with malnutrition develop oedema (kwashiorkor) is not well understood. The objective of this study was to investigate socio-demographic, dietary and clinical correlates of oedema, in children hospitalised with severe acute malnutrition.

METHODS

We recruited children with severe acute malnutrition admitted to Mulago Hospital, Uganda. Data was collected using questionnaires, clinical examination and measurement of blood haemoglobin, plasma c-reactive protein and α1-acid glycoprotein. Correlates of oedema were identified using multiple logistic regression analysis.

RESULTS

Of 120 children included, 77 (64%) presented with oedematous malnutrition. Oedematous children were slightly older (17.7 vs. 15.0 months, p = 0.006). After adjustment for age and sex, oedematous children were less likely to be breastfed (odds ratio (OR): 0.19, 95%-confidence interval (CI): 0.06; 0.59), to be HIV-infected (OR: 0.10, CI: 0.03; 0.41), to report cough (OR: 0.33, CI: 0.13; 0.82) and fever (OR: 0.22, CI: 0.09; 0.51), and to have axillary temperature > 37.5 °C (OR: 0.28 CI: 0.11; 0.68). Household dietary diversity score was lower in children with oedema (OR: 0.58, CI: 0.40; 85). No association was found with plasma levels of acute phase proteins, household food insecurity or birth weight.

CONCLUSION

Children with oedematous malnutrition were less likely to be breastfed, less likely to have HIV infection and had fewer symptoms of other infections. Dietary diversity was lower in households of children who presented with oedema. Future research may confirm whether a causal relationship exists between these factors and nutritional oedema.

Infant feeding in Nigeria

A study by questionnaire of 1845 urban and 349 rural mothers in all regions of Nigeria is reported. 99% of all mothers commenced breastfeeding their infants. In urban areas most continued for at least 6 months and in rural areas for at least 12 months. In urban areas, 77% of the infants were given infant formula by the age of 3 months; in rural areas 40% were given infant formula. Cereals were also introduced early to many children. The reasons for and the effects of this pattern of infant feeding are not clear, but it presumably meets the overall needs of the population. Further investigation is needed before attempts are made to enforce change.

CD4 counts decline despite nutritional recovery in HIV-infected Zambian children with severe malnutrition

OBJECTIVE

The objective of this study was to establish the contribution that severe malnutrition makes to CD4 lymphopenia in HIV-infected and uninfected children and to determine the changes in CD4 count during nutritional rehabilitation.

METHODS

Fifty-six children with severe malnutrition and with and without HIV infection were recruited from a pediatric ward in Lusaka for measurement of CD4 counts on admission, on discharge, and at final nutritional recovery.

RESULTS

HIV-uninfected children with severe malnutrition had normal CD4 counts. In contrast, CD4 counts in HIV-infected children with severe malnutrition were reduced, more so in those without edema compared with those with edema. Mean CD4 count of HIV-infected SM children fell despite nutritional recovery so that at the time of full nutritional recovery, >85% of HIV-infected children required antiretroviral therapy.

CONCLUSIONS

Severe malnutrition did not reduce the CD4 counts of children without HIV. HIV-infected children with severe malnutrition may respond well to nutritional rehabilitation, despite low CD4 counts, but nearly all require early antiretroviral therapy to prevent disease progression.

Glutathione S-transferase polymorphisms may be associated with risk of oedematous severe childhood malnutrition

It has been estimated that more than 50% of deaths before the age of 5 years have undernutrition as an underlying cause. Severe childhood malnutrition, an extreme form of undernutrition, occurs as oedematous and non-oedematous syndromes. The reasons why only some children develop oedematous severe childhood malnutrition (OSCM) have remained elusive, but the heterogeneity of clinical appearances among children from relatively homogeneous backgrounds suggests that interindividual variation in susceptibility to OSCM may exist. We investigated variants of four glutathione S-transferase (GST) genes in a retrospective study among subjects (n136) previously admitted to the Tropical Metabolism Research Unit, Jamaica, for the treatment of either OSCM (cases) or non-oedematous severe childhood malnutrition (controls). We found that GSTP1 Val105 homozygotes were significantly more common among the cases (odds ratio (OR) 3·5; 95% CI 1·1, 10·8). We also found an association of borderline significance between non-deletion GSTT1 genotypes (i.e. +/+ or +/0) and OSCM (OR 2·4; 95% CI 1·0, 5·9). There was no significant association between OSCM and any of the other GST variants. These preliminary findings suggest that genetic variation within the GST superfamily may contribute to the risk of OSCM. Additional, larger data sets and studies of variants in other candidate genes are required in order to properly assess the true contribution, if any, of genetic variation to risk of OSCM. Such studies may improve our understanding of the causes of clinical heterogeneity in malnutrition.

Polymorphisms in genes involved in folate metabolism as risk factors for oedematous severe childhood malnutrition: a hypothesis-generating study

BACKGROUND

Severe childhood malnutrition (SCM) occurs as both oedematous and non-oedematous syndromes. The reasons why some children develop oedematous SCM (OSCM) have remained elusive but differences in clinical presentation among malnourished children from similar backgrounds suggests that there might be inter-individual variation in susceptibility to OSCM.

AIM

To estimate the strength of the association between variants of three genes involved in folate/methyl group metabolism [methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR) and cystathionine beta-synthase (CBS)] and risk of OSCM.

METHODS

Patients previously admitted to the Tropical Metabolism Research Unit (TMRU) for treatment of either OSCM (cases, n = 74) or non-oedematous SCM (NOSCM, controls, n = 50) were recruited. Genotypes at four sites within the three genes (MTHFR C677T, MTHFR A1298C, MTR A2756G and CBS 844ins68) were determined using PCR-based assays.

RESULTS

The MTHFR 677T [odds ratio (OR) 0.63, 95% CI 0.2-1.7] and MTR 2756G (OR 0.74, 95% CI 0.4-1.4) alleles were associated with moderate reduction in risk of OSCM whereas the CBS 844ins68 allele (OR 1.4, 0.7-2.4) was associated with an increased risk. None of these risks was significant at the 5% level.

CONCLUSIONS

Genetic variation within folate/methyl group metabolic pathways might have a small but potentially important influence on risk of OSCM. Additional, larger data-sets will be required to test the specific hypotheses (about the putative effect size and direction of association) generated in this preliminary study. Such observations have the potential to improve our understanding of the pathogenesis of clinical heterogeneity in severe malnutrition.

Feeding patterns of children with protein-energy malnutrition in Nigeria

The feeding patterns of 115 consecutive cases of children suffering from protein-energy malnutrition (PEM) seen at Ile-Ife University Teaching Hospital, were investigated. The majority of the children were from Ile-Ife township and nearly all their mothers were working outside their respective homes. The survey shows an earlier mean age (27 months) of onset of kwashiorkor compared with Naismith's (1973) study. About two-thirds of the mothers had stopped breastfeeding their children by the age of 17 months. Artificial milk was introduced briefly, in token quantity, and was replaced by “corn-pap” and other starchy foods such as “yam” and “hard-pap”. Over 80% of mothers would not feed their children on meat and fish because they believed these foods would cause worms which, in turn, would cause abdominal pain and loss of weight. Cow's milk, groundnut and cowpeas were said to cause diarrhoea by about two-thirds of the mothers.

Our study shows that cessation of breastfeeding, inadequate feeding on artificial milk, and cultural beliefs about appropriate weaning diets for the infants were the major causes of PEM in this part of the world.

High-density-lipoprotein-cholesterol in protein-energy malnutrition

1. Plasma total cholesterol, high-density-lipoprotein (HDL)-cholesterol total protein, albumin and globulin levels were estimated in blood samples from thirty children with kwashiorkor, thirty-five with marasmus, twenty-eight with marasmic-kwashiorkor and twenty-seven control children. 2. HDL-cholesterol was estimated after the very-low-density and low-density lipoproteins were precipitated from the plasma with heparin and manganese chloride. 3. The distribution of HDL-cholesterol in the control and in the children with PEM was skewed and the range of values was wide. The values were independent of age and sex. 4. After logarithmic transformation of the HDL-cholesterol and HDL-cholesterol:total cholesterol values, the geometric mean values for the three groups of children with PEM were significantly decreased when compared with values for the control children. 5. The decrease in the mean HDL-cholesterol value for the children with kwashiorkor was more than for children with marasmus and marasmic-kwashiorkor.

Measurements of skinfold thickness and musculature in the assessment of growth and nutritional status of malnourished children

Measurements of the mid-upper arm circumference and the triceps skin-fold thickness were made at six montly intervals in 15 malnourished children. From these measurements, values were obtained for 'muscle bulk' and 'fat bulk' using local standards. Over a 12 month period, both measurements increased among the overtly malnourished children. The fat increased most in the children who were initially underweight (marasmic children). All these indicated an improvement in the nutritional status of these children. The Oje group of children deteriorated in all the parameters without any evidence of acute illness. A possible reason for this situation was a false sense of confidence on the part of the children's mothers and consequently, inadequate provision of food. The use of subcutaneous fat as an index of inadequate intake, and skeletal muscle for evidence of protein depletion, was also highlighted.