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 Children whose F-75 had partially been replaced by rice porridge during their hospital admission had less increase in thymus area after 8 weeks.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 .

[Oedematous malnutrition can also be seen in Danish children].

We describe two children with oedematous malnutrition; one admitted to a nutrition unit in Uganda and another to a paediatric department in Denmark. Both children received nutritional therapy and recovered. Although oedematous malnutrition is rarely seen in industrialized countries, the condition has been associated with chronic diseases. It is a life-threatening condition, and the pathogenesis remains unknown. Specialized nutrition products have been developed for low-resource clinics in developing countries, however, no specific protocols or products are available for physicians in Denmark.

Essential fatty acid composition and correlates in children with severe acute malnutrition.

BACKGROUND: Severe acute malnutrition (SAM) is a common condition in children living in low-income countries and may be associated with reduced polyunsaturated fatty acids (PUFA) blood levels. The purpose of this study was to describe whole blood fatty acid composition and correlates of PUFA in children admitted with SAM. METHODS: We conducted a cross-sectional study among children admitted with SAM at Mulago National Referral Hospital and healthy controls. Whole blood fatty acid composition was measured and correlated with clinical data such as oedema, levels of haemoglobin, C-reactive protein and HIV-infection status. Multiple linear regression analyses were used to identify correlates of PUFA. RESULTS: The relative contribution of saturated fatty acid to the fatty acids in whole blood (FA%) were lower in 108 children with SAM compared to 24 well-nourished controls whereas most monounsaturated fatty acids were higher in children with SAM. Total and all n-6 PUFA including linoleic (18:2n-6, LA) and arachidonic acid (20:4n-6, AA), as well as total n-3 PUFA and docosahexaenoic acid (22:6n-3, DHA) were lower in children with SAM. The n-6:n-3 PUFA ratio was also lower in the children with SAM. Haemoglobin was a positive correlate of AA, n-3 docosapentaenoic acid (22:5n-3, n-3 DPA), DHA, total n-6 long chain (LC) PUFA and total n-3 LCPUFA. HIV infected children had 0.87 (0.47; 1.58) %-points less n-6 LCPUFA and 0.61 (0.03; 1.19) %-points less AA than the un-infected children. CONCLUSION: Children with SAM presented with lower FA% of LCPUFA. HIV infection and low haemoglobin were also associated with lower FA% of LCPUFA, which may be related to lower numbers of blood cells. Nutrition rehabilitation interventions need to pay more attention to the intake of PUFA.