Abstract
BACKGROUND: Renal size is an important parameter in the assessment of a child with renal disease. Renal size can be estimated by measuring renal length, renal volume, and cortical volume or thickness. Renal length depends on different factors, which include size, body mass index and gender. Ultrasonography is useful, non-invasive and easily available method for reliably performing the measurement of kidney length. This study was conducted to find out correlation between renal length and age and anthropometric variables in healthy children. This prospective cross sectional study was carried out with the following objectives: (a) To determine the anthropometric variable that correlated best with renal length in healthy children. (b) To develop a nomogram for renal length in healthy children. METHODS: Five hundred healthy children were included in this study. Sonographic assessment of renal length was performed using real time mechanical sector scanner with 5 MHz and 8 MHz frequency. The renal length was correlated with somatic parameters like age, weight, height, body surface area and body mass index. Regression equations were derived for each pair of dependent and independent variables. RESULTS: We performed the measurement of renal length in 500 healthy children. In our series, renal measuring parameters showed a good correlation with studied body parameters, height having the best correlation. Data from left and right kidneys are shown separately since there was small but statistically significant difference between them. Based on our study, using the height of the child, renal length may be calculated by using following equation: Left renal length (cm) = 0.052 × height (cm) + 1.042, Right renal length (cm) = 0.052 × height (cm) + 0.867. CONCLUSIONS: This study provides values of renal length (mean ± 2SD) in normal Indian children and its correlation with body parameters. Renal length may be easily calculated by derived linear regression equation. Nomograms of renal length with respect to age and height have been formulated. Renal Length was found to correlate best with height of the child.