Vitamin A status of pre-school children in Ibadan (South West Nigeria), risk factors and comparison of methods of diagnosis.

Vitamin A deficiency (VAD) and protein energy malnutrition (PEM), sharing common aetiological factors, are important public health problems in many developing, countries. A cross-sectional survey of the vitamin A status of 128 well nourished and 230 malnourished pre-school children was carried out in order to define factors associated with increased risks of VAD and also to determine the predictive values of CIC-T in identifying serum retinol of < 10 microg/dl in these children. The proportional morbidity rates of VAD defined by serum retinol concentrations (7.3%) and CIC-T (6.2%) was similar (p>0.05), and children aged < 3 years accounted for 70% of VAD cases. VAD occurred in 6.3% and 7.8% of well-nourished and malnourished children respectively. The risk of VAD was increased following measles, history of persistent diarrhoea and wasting. The predictive value of CIC-T is highly dependent on CIC-T such that abnormal and normal smears classification appears to be very robust and predictive of serum retinol of < 10 microg/dl, with sensitivity of 83.3% (95%CI: 61.8-94.5), and specificity of 73.3% (95%CI: 68.3-78.5). Judging by the proportional morbidity rate in this study, VAD appears to be a significant public health problem in both malnourished and well-nourished Nigerian children, especially in children < 3 years of age. The history of measles and persistent diarrhoea appear to increase the risk of VAD. The simplicity, sensitivity and specificity of CIC-T suggest that this procedure is a good screening tool for epidemiological survey of vitamin A status.