Vitamin A deficiency in pre-school children in Kenya.

OBJECTIVE: To determine the prevalence of vitamin A in pre-school children in Kenya. DESIGN: Cross-sectional survey. SETTING: Fourteen districts randomly selected from the eight provinces in Kenya. SUBJECTS: Six thousand four hundred and twenty five pre-school children (3298 boys and 3127 girls) aged 6-72 months in 27 clusters randomly selected from fourteen districts. MAIN OUTCOME MEASURES: Serum retinol levels and xerophthalmia were determined using High Pressure Liquid Chromatography (HPLC) and ophthalmological assessment respectively. RESULTS: The mean serum retinol was 0.84 mmol/l +/- 0.58 SD. The mean serum retinol by sex was 0.82 +/- 0.51 SD and 0.87 +/- 65 SD (p=0.005) for boys and girls respectively. Over seven per cent of the children were severely vitamin A deficient (<0.35 mmol/l) and 32.9% had marginal vitamin A deficiency (0.70 mmol/l). In the age group six to eleven months, 11.2% and 40.7% of the children were severely and marginally vitamin A deficient, respectively. Clinical examination results indicated that 0.1% of children had corneal xerosis (X2), and one per cent of the children had Bitot's spots (XIB). Geographically, the results show that the problem is most prevalent in Kwale, Mombasa, Kitui, Baringo, Kisumu, Kisii, Bungoma, Garissa and Mandera. CONCLUSION: This survey demonstrated that regardless of the assessment method used, vitamin A deficiency is a significant public health problem in Kenya which requires urgent interventions. The group at highest risk was children aged six to twenty three months. Boys were at more risk than girls.

Measurement of physiological concentrations of dapsone and its monoacetyl metabolite: a miniaturised assay for liquid or filter paper-absorbed samples.

A modification of existing HPLC assay methods is described for the measurement of dapsone and monoacetyldapsone in 50-microliter samples of plasma and whole blood. This method, in particular the use of small sample volumes dried onto filter paper strips, is applicable to multi-sample clinical and pharmacokinetic studies in children with malaria, who are often anaemic, and where sample volume must be kept to a minimum. Basified samples were extracted into 5 ml of ethyl acetate-tert.-butylmethyl ether (1:1, v/v), chromatographed on a mu BondapaK C18, 10-micron column with water-acetonitrile-glacial acetic acid (81:17.5:5, v/v) containing 2 g/l l-octanesulphonic acid as the mobile phase and detected at 274 nm.