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.

Retinoblastomas in Ibadan Nigeria: II--Clinicopathologic features.

Retinoblastomas are primary malignant intraocular neoplasms of childhood displaying photoreceptor differentiation. The present study reviews clinicopathological features of these neoplasms in Ibadan, Nigeria. Clinical, surgical pathology, and histological material of 44 histologically verified cases of retinoblastoma indexed in the Cancer Registry, University of Ibadan were analyzed. Retinoblastomas accounted for 1.1% of all malignant neoplasms and were equally frequent in male and female children. The mean age of our patients at the time of diagnosis was 32.3 months, which exceeds a corresponding age of 16-21.5 months recorded among Caucasian children. Leukocoria was the most common clinical manifestation. Eighteen percent of our patients had bilateral neoplasms. These patients were significantly younger than those with unilateral retinoblastomas. Flexner-Wintersteiner rosettes occurred in 61% and optic nerve involvement in 78% of the cases and the sites of predilection were regional lymph nodes, scalp, jaw, brain, skull, long bones, and gum.

Conjunctival impression cytology with transfer in the assessment of vitamin A status in Nigerian children.

OBJECTIVE: To determine vitamin A status by conjunctival impression cytology with transfer (CIC-T) and assess its ability to predict low and deficient serum retinol concentrations. STUDY DESIGN: CIC-T was performed on 128 healthy, well-nourished and 230 malnourished children aged under 6 years by a 3-5-second application of cellulose acetate paper to each bulbar conjunctiva followed by transfer of the adhered cells onto glass slides. The slides were stained with Alcian green 2GX, and smears were classified as normal, borderline normal, borderline abnormal and deficient. Corresponding serum retinol levels were determined in each subject. RESULTS: The results showed that CIC-T is a simple procedure with a failure rate of 7.3% caused by tearing and agitation. The power of CIC-T to predict vitamin A status varied with both the CIC-T smear classification used and serum retinol concentration threshold. CIC-T smear classification as abnormal and normal appears to be the most robust and predictive of serum retinol, < 10 and > 10 < 20 micrograms/dL, respectively. CONCLUSION: The simplicity, sensitivity and specificity of CIC-T suggest that this procedure is a good screening tool for epidemiologic survey of vitamin A status.

Retinoblastomas in Ibadan: treatment and prognosis.

This study reviews the influence of different clinicopathological features of retinoblastoma on outcome and prognosis in 44 Nigerian patients. Twenty-five of the patients had a fatal outcome. These patients were younger and more frequently had bilateral retinoblastomas, orbital tumour recurrence and tumour metastases, compared to patients who had disease free survival. Postoperative tumour recurrence occurred in eleven patients and was commoner in patient who had tumour metastases. Tumour metastases occurred in eighteen of the patients. Though there has been an improvement in the prognosis of retinoblastoma at Ibadan with the advent of radiotherapy, the outlook for children with this neoplasm in this environment is still bleak in comparison with what obtains in developed countries.

Tumours of the eye and orbit in Ibadan.

Four hundred and forty ocular and orbital tumours seen in Ibadan over 11-year-period (1980-1990) are reviewed. Three quarters of the 252 patients who had enucleation had malignant neoplasms, of which 55% were retinoblastomas. The mean age of patients with retinoblastomas (3.2 years) was less than that of patients with carcinoma and malignant melanomas (47 years). Malignant melanomas were rare neoplasms in Ibadan. The commonest orbital lymphoma was Burkitt's lymphoma. Only 24% of the enucleated eyes had inflammatory conditions, of which 38% gave a positive history of trauma. Inflammatory lesions were the commonest benign ocular diseases accounting for 33% of these latter cases. Postmeasles keratitis was a significant associated finding in these patients.