Vitamin A has well recognised benefits for the reduction in severity of
diarrhoeal episodes but the impact of therapeutic doses given during diarrhoea on
the biochemical and clinical outcomes is less clear. In this study these potential
therapeutic benefits were investigated to establish the optimum time for vitamin A
supplementation to improve vitamin A status. Establishing the optimum time for
vitamin A supplementation during an infectious stage would improve cost effectiveness
and clinical benefit.
Young children (174) between the ages of 3 and 60 months with severe
diarrhoea were randomised in a double - blinded placebo controlled trial into one
of 2 groups. The 1 st group received 60 mg of retinol as retinyl palmitate on
admission during the acute diarrhoeal stage. The 2nd group received the same
dose of vitamin A once symptoms had resolved, usually between 3 - 7 days. At
each of these two time points, children not receiving vitamin A were given an
identical placebo dose. Baseline (day 0) and day 3 serum samples were
collected for vitamin A, retinol binding protein (RBP) and other biochemical
markers. At four and eight weeks after discharge both morbidity and weight gain
were recorded. The modified dose response test (MRDR) was conducted at the
eight - week follow - up to estimate vitamin A liver stores.
Initially, most of the children presented with watery diarrhoea and
dehydration and were clinically very ill. At day 3 plasma retinol concentrations
improved in both groups viz. from 0.57umol/L to 0.97umol/L in the 1st group and
from 0.49umol/L to 0.90umol/L in the 2nd group. Similar improvements were
found in retinol binding protein viz. 21.28 mg/L to 31.06 mg/L in the 1st group and
17.05 mg/L to 24.80 mg/L in the 2nd group. At 8 weeks there was also no
significant difference between the two groups either for serum retinol (0.69umol/L
and 0.73umol/L respectively) nor for MRDR ratios (0.036 and 0.049 respectively).
The MRDR results at 8 weeks indicated that these children did not have
depleted vitamin A liver stores and that the low serum retinol levels seen at
baseline were probably due to the acute phase response during an infectious
episode.
The results of these analyses showed no significant difference between the
two treatment groups thus indicating that there was no benefit to giving vitamin A
on recovery from an infectious episode instead of on admission, as is currently
practised. / Thesis (M.Med.Sc.)-University of Natal, Durban, 2001.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ukzn/oai:http://researchspace.ukzn.ac.za:10413/8349 |
| Date | January 2001 |
| Creators | Elson, Karin Inga. |
| Contributors | Coutsoudis, Anna. |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
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