This paper describes the vitamin B12 and folate concentrations of HIV-infected Ugandan children aged 1-5 years and the effect of 2RDA of 14 multiple micronutrients that contained vitamin B12 and folate versus the 'standard of care' multivitamins in 1RDA without vitamin B12 and folate. Almost a third of the children had low vitamin B12 and low folate concentrations at baseline. Very low serum concentrations were uncommon. MMS containing vitamin B12 and folate improved both vitamin B12 and folate concentrations compared to the 'standard of care' multivitamins.
Vitamin B12 and folate concentrations in our study are comparable or slightly lower than what has been reported in children living in other low-income countries [1, 2, 4, 17]. Our findings are also comparable to what other studies in HIV infected adults reported before the HAART era. These studies showed that low vitamin B12 concentrations were relatively common with a prevalence ranging between 10 and 35% [18–22].
There are few studies that have examined vitamin B12 and folate in HIV infected children in Africa. The prevalence of low vitamin B12 concentrations in our study was much higher than the prevalence of 5% reported in South African HIV infected children . Contrary to our findings a study of HIV infected children in New York showed elevated vitamin B12 and folate status . Our study included younger children, the majority of whom were symptomatic and not on HAART compared to the New York study. In our study the lack of differences between the HAART and non-HAART stratum in baseline vitamin B12 or folate concentrations could be explained by the short duration of HAART compared to other studies.
Twice the recommended dietary allowance of multiple micronutrients improved vitamin B12 and folate status compared to the 'standard of care'. This is not surprising since the standard of care supplement did not contain vitamin B12 and folate. This implies that the standard of care multivitamin is not enough and many more micronutrients may be required to correct micronutrient deficiencies. A significant number of children still had low concentrations of vitamin B12 and folate at the end of 6 months, implying that the duration of supplementation needed to be extended.
Low vitamin B12 could be related to folate deficiency or to low vitamin B12 binding proteins. Although we did not find an association between low vitamin B12 and white blood cell count this does exclude the possibility that low vitamin B12 concentrations could be related to neutropenia.
We observed that there was an association between low folate concentrations and low haemoglobin which indicates that the anaemia could partly be attributed to low folate concentrations. In both treatment groups the haemoglobin improved compared to baseline levels. We could not conclusively attribute the anaemia to low folate concentrations since we did not measure red blood cell folate concentrations. Measuring both serum folate and Red cell folate would have yielded more diagnostic information of folate deficiency. However sub-normal serum folate is a useful indicator of folate status that warrants reporting. In a landscape of multiple deficiencies, such as HIV-infected children in a low-income country, there is always the potential for other deficiencies to alter the response, for instance, iron deficiency (the supplement did not contain iron). Folate deficiency has been reported in almost one in two anaemic HIV infected patients . Other authors have reported associations between anaemia, gender and folate deficiency in children whose HIV infection status was not known .
Neither MMS nor the 'standard of care' MV improved the immunological status of the study children. In fact there was a slight deterioration in the CD4+ cell counts among the HAART naïve MMS group. This was contrary to findings of a trial in HAART treated HIV infected adults living in the USA where multiple micronutrient supplementation was associated with improved CD4+ cell count compared to a placebo . The lack of effect on CD4+ cell count in our study could be explained by the natural immunological deterioration or it may be apparent due to the small numbers in the HAART group. It is also possible that the supplementation was not long enough to show an impact on CD4+ cell count since one in five children still had low vitamin B12 and folate concentrations at 6 months of follow up.
In our setting it is possible that low concentrations of vitamin B12 and folate may be related to consumption of marginal or low levels of vitamin B12 and folate since twice the recommended dietary intakes increased serum concentrations as opposed to the multivitamin supplement which did not contain vitamin B12 or folate. Some authors have shown that Vitamin B12 deficiency is rare in HIV infected persons consuming vitamin B12 well above the recommended nutrient intakes . In Uganda one third of children aged between 6 and 24 months are likely to be getting diary products in their diet and very few are likely to be getting other animal source foods .
We are not certain whether our findings are similar to children in the general population since we had no control group of HIV uninfected children. A study of both HIV-infected and exposed uninfected children in Brazil showed no differences in micronutrient status . However another study indicated that HIV infected children had significantly lower folate levels than the reference children while vitamin B12 was similar .
We were unable to measure serum homocysteine and methyl malonic acid concentrations which are more reliable indicators of vitamin B12 deficiency because of the limited amount of blood that we could draw from the children as we had multiple micronutrients to test for. We also did not conduct absorption studies to examine the impact of malabsorption on baseline micronutrient and post-supplementation status. This paper does not describe the dietary habits of the study children and whether they had an impact on the outcome.