Changes in plasma phosphate during in-patient treatment of children with severe acute malnutrition: an observational study in Uganda

High Incidence of Refeeding Syndrome during the Transition from F75 to Ready-to-Use Therapeutic Feeds among Children 6 to 59 Months with Severe Acute Malnutrition at the Pediatric Nutritional Unit of Mulago Hospital

Background

Refeeding syndrome is a complication developed by children being managed for severe acute malnutrition (SAM). It is caused by changes in electrolyte balance once high-caloric feeding is reinitiated. Phosphorus, potassium, and magnesium are the main electrolytes affected when it occurs. However, hypophosphatemia is the hallmark of the diagnosis of refeeding syndrome. WHO recommends inpatient management of patients with complicated SAM with initially F75 which is low in calories and later transitioned to RUTF which is high in calories but also has a higher phosphorus content.

Objective

This study aims to determine the incidence and factors associated with refeeding syndrome in the transition phase when treating children aged 6 to 59 months with severe acute malnutrition at the Mwanamugimu Nutritional Unit, Mulago.

Methods

We conducted a prospective cohort study at the Mwanamugimu Nutritional Unit of Mulago National Referral Hospital. A total of 150 children between 6 and 59 months with SAM were enrolled into the study. We measured serum electrolytes (phosphorus, sodium, and potassium) at admission, initiation of RUTF, and 48 hours after transition. The refeeding syndrome was diagnosed by a drop in serum phosphorus of more than 0.3 mmol from baseline. The data were analyzed using STATA 17.0. Incidence of refeeding syndrome was determined as the proportion of participants whose serum phosphorus declined by more than 0.3 mmol from baseline. For factors associated, a multivariate-modified Poisson regression analysis reporting relative risk was performed with a 0.2 level of significance at bivariate and 0.05 at multivariate analyses.

Results

Of the 150 children recruited, 35 were lost to follow-up and 115 children had their data analyzed. Of the 115 participants in the study, 40 developed refeeding syndrome indicating a cumulative incidence of 34.8% with a 95% CI of 26.5-44%. A low baseline serum sodium (RR: 0.89, 95% CI: 0.80-0.99, and P value: 0.038) and having edematous malnutrition (RR: 0.90, 95% CI: 0.81-0.99, and P value; 0.042) at admission were found to be significant (P < 0.05) risk factors of refeeding syndrome.

Conclusion

The cumulative incidence of RFS of 34.8% is very high. RFS is found to be associated with low baseline sodium and pedal edema. Children with a low baseline sodium and edema should undergo a cautious transition of feeds.

Micronutrient status in children aged 6-59 months with severe wasting and/or nutritional edema: implications for nutritional rehabilitation formulations

Undernutrition remains a global struggle and is associated with almost 45% of deaths in children younger than 5 years. Despite advances in management of severe wasting (though less so for nutritional edema), full and sustained recovery remains elusive. Children with severe wasting and/or nutritional edema (also commonly referred to as severe acute malnutrition and part of the umbrella term "severe malnutrition") continue to have a high mortality rate. This suggests a likely multifactorial etiology that may include micronutrient deficiency. Micronutrients are currently provided in therapeutic foods at levels based on expert opinion, with few supportive studies of high quality having been conducted. This narrative review looks at the knowledge base on micronutrient deficiencies in children aged 6-59 months who have severe wasting and/or nutritional edema, in addition to highlighting areas where further research is warranted (See "Future Directions" section).

Effects of dairy and plant protein on growth and growth biomarkers in a piglet model

The increasing world population with improved living conditions has increased the demand for food protein. This has intensified the search for sustainable alternative plant-derived high-quality protein sources for human nutrition. To study the effect of plant and milk proteins on growth in weaned pigs as a model for humans, 96 weaned pigs were divided into 48 pens and fed one of 4 different diets for 3 weeks. The dietary protein originated from either 50% rice + 50% 00-rapeseed protein (RICE + RAPE), 50% milk protein (MPC) + 50% 00-rapeseed protein (MPC + RAPE), 50% milk + 50% rice protein (MPC + RICE), or 100% MPC, and were supplemented with crystalline amino acids to meet the amino acid requirements. Weekly feed intake and body weights were recorded and after 3 weeks, a blood sample was taken 1 hour after a fixed meal, while organ weights were measured, and liver- and muscle tissue, and bone samples were collected at euthanasia. All pigs had a high daily gain and a low feed-to-gain ratio (F : G, feed intake per kg weight gain), but feed intake and daily gain was lowest and F : G highest in the RICE + RAPE diet. Metacarpal bones were longer and heavier in MPC + RICE and MPC fed pigs compared to pigs fed diet RICE + RAPE (P < 0.05), and intermediate in MPC + RAPE fed pigs, with no differences in bone thickness (P > 0.05). Plasma levels of all essential amino acids except Cys and Lys decreased markedly when fed a diet containing only plant protein. The differences were not associated with differences in plasma insulin or IGF-1, nor in the abundance of mRNA related to growth in liver and longissimus dorsi muscle. In conclusion, the growth of piglets fed a combination of milk and rice protein did not differ from the pure dairy-based diet, whereas the pure plant-based diet consisting of rice and rapeseed protein led to reduced growth. This was most likely caused by a lower feed intake and a lower than expected amino acid digestibility of the 00-rapeseed protein. There were no indications that the milk protein, beyond a favourable amino acid composition and high digestibility, specifically stimulated growth factors or other biomarkers of growth via the IGF-1 and insulin signalling pathways.

Hypophosphataemia in severe acute malnutrition: a prospective observational study

Severe acute malnutrition (SAM) is a major cause of child mortality and morbidity. Children treated for SAM are at risk of refeeding hypophosphataemia (HP). The study was done to find out the incidence and various predictors of moderate/severe HP in SAM among North Indian children. This prospective observational study was conducted from August 2014 to July 2015 in the inpatients' department of Department of Paediatrics at King George's Medical University, Lucknow, Uttar Pradesh, North India, a tertiary care teaching hospital. Before inclusion, ethical approval and written informed consent was obtained. Included in the study were sixty-five children aged 6-59 months of age, who were admitted to the hospital with SAM as per the WHO guidelines. SAM was defined as a mid-upper arm circumference <115 mm and/or weight-for-height/length <-3 z-scores of the WHO growth standards and/or have bilateral oedema. Serum P levels were measured on admission and for five consecutive days after starting feed. HP was defined as mild, moderate and severe with a cut-off of 1·19-0·65, 0·65-0·32 and <0·32 mmol/l, respectively. About 60 % children had HP, with 20 % having moderate/severe HP at admission. The proportion of HP increased to 83·1 %, with 38·5 % having moderate/severe HP on day 3 after feeding. It was concluded that HP is a common biochemical abnormality in SAM. Considering its impact on the health of the child, serum P levels should be monitored in patients with SAM who are treated with enteral feeding.

Transition from F-75 to ready-to-use therapeutic food in children with severe acute malnutrition, an observational study in Uganda

BACKGROUND

World Health Organization now recommends the transition from F-75 to ready-to-use therapeutic foods (RUTF) in the management of severe acute malnutrition (SAM). We described the transition from F-75 to RUTF and identified correlates of failed transition.

METHODS

We conducted an observational study among children aged 6-59 months treated for SAM at Mulago hospital, Kampala, Uganda. Therapeutic feeding during transition phase was provided by first offering half of the energy requirements from RUTF and the other half from F-75 and then increasing gradually to RUTF as only energy source. The child was considered to have successfully transitioned to RUTF if child was able to gradually consume up to 135 kcal/kg/day of RUTF in the transition phase on first attempt. Failed transition to RUTF included children who failed the acceptance test or those who had progressively reduced RUTF intake during the subsequent days. Failure also included those who developed profuse diarrhoea or vomiting when RUTF was ingested.

RESULTS

Among 341 of 400 children that reached the transition period, 65% successfully transitioned from F-75 to RUTF on first attempt while 35% failed. The median (IQR) duration of the transition period was 4 (3-8) days. The age of the child, mid-upper arm circumference, weight-for-height z-score and weight at transition negatively predicted failure. Each month increase in age reflected a 4% lower likelihood of failure (OR 0.96 (95% CI 0.93; 0.99). Children with HIV (OR 2.73, 95% CI 1.27; 5.85) and those rated as severely ill by caregiver (OR 1.16, 95% CI: 1.02; 1.32) were more likely to fail. At the beginning of the rehabilitation phase, the majority (95%) of the children eventually accepted RUTF while only 5% completed rehabilitation in hospital on F-100.

CONCLUSION

Transition from F-75 to RUTF for hospitalized children with SAM by gradual increase of RUTF was possible on first attempt in 65% of cases. Younger children, severely wasted, HIV infected and those with severe illness as rated by the caregiver were more likely to fail to transit from F-75 to RUTF on first attempt.

Changes in serum phosphate and potassium and their effects on mortality in malnourished African HIV-infected adults starting antiretroviral therapy and given vitamins and minerals in lipid-based nutritional supplements: secondary analysis from the Nutritional Support for African Adults Starting Antiretroviral Therapy (NUSTART) trial

Malnourished HIV-infected patients starting antiretroviral therapy (ART) are at high risk of early mortality, some of which may be attributed to altered electrolyte metabolism. We used data from a randomised controlled trial of electrolyte-enriched lipid-based nutritional supplements to assess the association of baseline and time-varying serum phosphate and K concentrations with mortality within the first 12 weeks after starting ART. Baseline phosphate results were available from 1764 patients and there were 9096 subsequent serum phosphate measurements, a median of 6 per patient. For serum K there were 1701 baseline and 8773 subsequent measures, a median of 6 per patient. Abnormally high or low serum phosphate was more common than high or low serum K. Controlling for other factors found to affect mortality in this cohort, low phosphate which had not changed from the previous time interval was associated with increased mortality; the same was not true for high phosphate or for high or low K. Both increases and decreases in serum electrolytes from the previous time interval were generally associated with increased mortality, particularly in the electrolyte-supplemented group. The results suggest that changes in serum electrolytes, largely irrespective of the starting point and the direction of change, were more strongly associated with mortality than were absolute electrolyte levels. Although K and phosphate are required for tissue deposition during recovery from malnutrition, further studies are needed to determine whether specific supplements exacerbate physiologically adverse shifts in electrolyte levels during nutritional rehabilitation of ill malnourished HIV patients.

Correlates of thymus size and changes during treatment of children with severe acute malnutrition: a cohort study

Background

The impairment of immune functions associated with malnutrition may be one reason for the high mortality in children with severe acute malnutrition (SAM), and thymus atrophy has been proposed as a marker of this immunodeficiency. The aim of this study was to identify nutritional and clinical correlates of thymus size in children with SAM, and predictors of change in thymus size with nutritional rehabilitation.

Methods

In an observational study among children aged 6–59 months admitted with SAM in Uganda, we measured thymus area by ultrasound on hospital admission to treatment with F75 and F100, on hospital discharge and after 8 weeks of nutritional rehabilitation with ready-to-use therapeutic food, as well as in well-nourished healthy children. We investigated anthropometric, clinical, biochemical and treatment-related correlates of area and growth of the thymus.

Results

Eighty-five children with SAM with a median age of 16.5 months were included. On admission 27% of the children had a thymus undetectable by ultrasound. Median thymus area was 1.3 cm² in malnourished children, and 3.5 cm² in healthy children (p < 0.001). Most anthropometric z-scores, hemoglobin and plasma phosphate correlated positively with thymus area. Thymus area correlated negatively with caretaker-reported severity of illness, plasma α-1 acid glycoprotein, and C-reactive protein >5 mg/L. At follow-up after 8 weeks, median thymus area had increased to 2.5 cm² (p < 0.001). Increase in thymus area during treatment was associated with simultaneous increase in mid-upper-arm circumference, with 0.29 cm² higher increase in thymus area per cm larger increment in MUAC (p = 0.03). Children whose F-75 had partially been replaced by rice porridge during their hospital admission had less increase in thymus area after 8 weeks.

Conclusion

Malnutrition and inflammation are associated with thymus atrophy, and thymus area seems positively associated with plasma phosphate. Substituting therapeutic formula with unfortified rice porridge with the aim of alleviating diarrhea may impair regain of thymus size with nutritional rehabilitation. This calls for research into possible effects of phosphate status on thymus size and other immunological markers.

Trial registration

The study is based on data from the FeedSAM study, ISRCTN55092738.

Risk factors for death in children during inpatient treatment of severe acute malnutrition: a prospective cohort study

BACKGROUND

Children who receive in-hospital treatment of severe acute malnutrition often have high mortality rates, and the reasons are not well understood.

OBJECTIVE

We assessed risk factors for death in children who were treated for malnutrition in a hospital.

DESIGN

In a prospective observational study of 120 children who were receiving in-hospital treatment of severe acute malnutrition in Uganda with therapeutic formulas F-75 and F-100, we collected data on symptoms, clinical findings, plasma markers of refeeding syndrome (electrolytes and phosphate), and acute phase reactants, and recorded the nutritional therapy given in hospital.

RESULTS

Seventeen children (14%) died. Clinical risk factors for death were the presence of oral thrush (HR: 5.0; 95% CI: 1.6, 15.2), a caretaker-reported severity of illness on a visual analog scale (HR: 1.7; 95% CI: 1.1, 2.6), impaired consciousness (HR: 16.7; 95% CI: 3.1, 90.4), and a capillary refill time >2 s (HR: 3.9; 95% CI: 1.4, 11.3). HIV infection was not associated with mortality (HR: 3.0; 95% CI: 0.7, 12.4), which was most likely due to low power. Biochemical risk factors were a plasma C-reactive protein concentration >15 mg/L on admission and low plasma phosphate that was measured on day 2 (HR: 8.7; 95% CI: 2.5, 30.1), particularly in edematous children. The replacement of F-75 with unfortified rice porridge to ameliorate diarrhea was associated with a higher risk of death, particularly if given during the first 2 d (HR: 5.0; 95% CI: 1.9, 13.3), which was an association that remained after adjustment for potential confounders (HR: 69.5; 95% CI: 7.0, 694.6).

CONCLUSIONS

Refeeding syndrome may occur in children who are treated for malnutrition, even with moderately low plasma phosphate, and, in particular, in children with edematous malnutrition. The replacement of F-75 with unfortified rice porridge is associated with increased risk of death, which is possibly mediated by lowering plasma phosphate. The identified clinical risk factors may potentially improve the triage of children with malnutrition. This trial was registered at www.isrctn.com as ISRCTN55092738.

Changes in whole-blood PUFA and their predictors during recovery from severe acute malnutrition

Children with severe acute malnutrition (SAM) with complications require in-patient management including therapeutic feeding. Little attention has been given to the effects of these feeds on the essential fatty acid status of children with SAM. The objective of this study was to describe changes in the PUFA composition in whole blood in children with SAM during treatment and to determine predictors of change. This prospective study took place in a paediatric nutrition rehabilitation unit in Kampala, Uganda, and assessed whole-blood fatty acid composition of children with SAM at admission, transition, discharge and follow-up (8 and 16 weeks). ANCOVA was used to identify predictors of change in whole-blood PUFA. The study included 120 children with SAM and twenty-nine healthy control children of similar age and sex. Among the SAM children, 38 % were female and 64 % had oedema. Whole-blood n-6 PUFA proportions increased from admission to follow-up, except for arachidonic acid, which decreased by 0·79 (95 % CI 0·46, 1·12) fatty acid percentage (FA%) from admission to transition and 0·10 (95 % CI 0·23, 0·44) FA% at discharge. n-3 Long-chain (LC) PUFA decreased by 0·21 (95 % CI 0·03, 0·40) FA% at discharge and 0·22 (95 % CI 0·01, 0·42) FA% at 8 weeks of follow-up. This decrease was greater in children from families with recent fish intake and those with nasogastric tube feeding. Current therapeutic feeds do not correct whole-blood levels of LCPUFA, particularly n-3 LCPUFA, in children with SAM. Increased attention is needed to the contents of n-3 LCPUFA in therapeutic feeds.