Serum phosphate and magnesium in children recovering from severe acute undernutrition in Ethiopia: an observational study

Abstract

BackgroundChildren with severe acute malnutrition (SAM) have increased requirements for phosphorus and magnesium during recovery. If requirements are not met, the children may develop refeeding hypophosphatemia and hypomagnesemia. However, little is known about the effect of current therapeutic diets (F-75 and F-100) on serum phosphate (S-phosphate) and magnesium (S-magnesium) in children with SAM.MethodsProspective observational study, with measurements of S-phosphate and S-magnesium at admission, prior to rehabilitation phase and at discharge in children aged 6–59 months admitted with SAM to Jimma Hospital, Ethiopia. Due to shortage of F-75, 25 (35 %) children were stabilized with diluted F-100 (75 kcal/100 ml).ResultsOf 72 children enrolled, the mean age was 32 ± 14 months, and edema was present in 50 (69 %). At admission, mean S-phosphate was 0.92 ± 0.34 mmol/L, which was low compared to normal values, but increased to 1.38 ± 0.28 mmol/L at discharge, after on average 16 days. Mean S-magnesium, at admission, was 0.95 ± 0.23 mmol/L, and increased to 1.13 ± 0.17 mmol/L at discharge. At discharge, 18 (51 %) children had S-phosphate below the normal range, and 3 (9 %) had S-phosphate above. Most children (83 %) had S-magnesium above normal range for children. Both S-phosphate and S-magnesium at admission were positively associated with serum albumin (S-albumin), but not with anthropometric characteristics or co-diagnoses. Using diluted F-100 for stabilization was not associated with lower S-phosphate or S-magnesium.ConclusionHypophosphatemia was common among children with SAM at admission, and still subnormal in about half of the children at discharge. This could be problematic for further recovery as phosphorus is needed for catch-up growth and local diets are likely to be low in bioavailable phosphorus. The high S-magnesium levels at discharge does not support that magnesium should be a limiting nutrient for growth in the F-100 diet. Although diluted F-100 (75 kcal/100 mL) is not designed for stabilizing children with SAM, it did not seem to cause lower S-phosphate than in children fed F-75.

A cross-sectional analysis of factors associated with the development of refeeding syndrome in children 0 – 59 months diagnosed with severe acute malnutrition in a South African setting

“…Hypophosphatemia was present in 20% (n=25) of the 126 children in the current study (Table 3), which concurs with other studies that have reported low phosphate levels on hospital admission for children with SAM [9,18]. In agreement with the findings of Mbethe and Mda [4], hypophosphatemia was significantly (p=0.04) associated with RFS in the current study [5].…”

Serum Phosphate Profile of Children With Severe Acute Malnutrition Treated With Locally Prepared Therapeutic Feeds: A Prospective Observational Study

“…There was no significant difference in phosphate levels of children with or without diarrhea and dehydration. This was in accordance with studies done by Kimutai et al [3], Hother et al [4] and Okinyi et al [9]. However, Namusoke et al [5] reported a significant difference in hypophosphatemia prevalence at transition in children with or without diarrhea.…”

“…Prevalence of hypophosphatemia in our study was 25%, 23.3% and 8.3% on admission, during transition and at discharge, respectively. The prevalence on admission was comparable with studies by Namusoke et al (37%) and Dakshayani et al (17%) [5,8], while Kimutai et al (86%), Hother et al (93%) and Chanchal et al (60%) reported very high prevalence [3,4,7]. Higher prevalence in the study by Kimutai et al could be explained by difference in study population as they enrolled only children with edematous malnutrition.…”

“…Treatment with diets high in carbohydrate but with inadequate amount of phosphorus, magnesium, potassium and thiamine can result in refeeding syndrome which is characterized by hypophosphatemia, hypomagnesemia, hypokalemia and other abnormalities. On reviewing the literature, several studies reported varying prevalence of hypophosphatemia ranging from 17% to 93% [3][4][5][6][7][8][9]. Most of commercial premix (F-75) has added extrinsic phosphorus to meet United Nations procurement specifications of more than 60 mg/100 mL.…”

Hypophosphataemia in severe acute malnutrition: a prospective observational study

“…Other studies have reported a decrease in serum P on day 2 of treatment ( 21 , 22 , 27 , 28 ) . However, other studies ( 26 , 30 ) found increasing concentrations of serum P throughout the treatment period. This difference may be attributed to the type of therapeutic food used.…”