Determination of Normal Renal Size Among Children in Maiduguri, Borno State, North-eastern Nigeria

Abstract

Background: Measurement of the length and width of the kidneys using ultrasound scan is used to evaluate its rate of growth and the extent of kidney affectation by disease. Renal growth correlates well with somatic growth and is influenced by changes in the age, nutritional status and disease. Knowing renal size in relation to age and body size of a child will help to detect deviation from normal especially in diseased conditions that causes enlargement or reduction in renal size. Objectives: To determine the renal size of normal children by ultrasonography and correlation of renal size with age of the children. Methods: The data for renal size (renal length), sex and age of 404 children aged 1 month to 14 years were obtained. The (bipolar) lengths of both right and left kidneys were measured with ultrasonography by a sonographer. The age and sex each child was recorded in a preformed proforma. The weight was measured in the Children Outpatient Department (COPD) of State Specialist Hospital Maiduguri, Borno state using a standard weighing scale. Results: Four hundred and four (404) normal children aged 1 month to 14 years had abdominal ultrasound scan (USS) done. Their mean age was 7.9 (± 4.2 SD) years. There were 208 (51.5%) females and 196 (48.5%) males with female to male ratio of 1.1: 1. The mean age of females was 7.8 ± 4.2 SD while that of males was 8.0± 4.2 SD. There was no significance difference in their mean ages; p=0.494. There was rapid increase in the renal length in the first year of life and there was no statistically significant difference (p=0.50) in the mean renal length between males and females. There is good correlation between age and right renal length (r = 0.680) but low correlation (r = 0.290) between age and left kidney. Conclusion: There was rapid increase in the renal length in the first year of life and there is good correlation between age and renal size.