Correlation of Sonographically Determined Renal Sizes with Demographic Parameters in Nigerian Adults

Abstract

Renal dimensions are important for the diagnosis and the prognosis of nephropathies. Information on renal dimensions among normal Africans is scanty. The study aimed to define sonographically measured renal sizes and their relations to age, sex, height and weight among Nigerians in a hospital setting. A total number of 132 consecutive subjects, mean age 37.8 + 12.8 years (range 18-76years), were studied. Mean renal dimensions were obtained for both kidneys. The relationships of renal dimensions to age, height, weight and sex were determined. Renal dimensions were correlated with these parameters. Data were presented as mean ± SD and analyzed using SPSS 14.0 software. A p-value < 0.05 was considered as statistically significant. Mean Renal Dimensions: Mean renal lengths were 10.2+0.7cm (left side) and 10.0+0.8 cm (right side), p< 0.0001. Median renal volumes were 125.5+35.1 cm3 and 118.7+33.3
cm3 respectively. There were statistically significant correlations between the patients’ weight, height, renal length and renal volume and Body Surface Area, but not with Body Mass Index. A simple linear regression equation obtained predicted renal lengths based on height: renal length = 6.1078 + 0.0248 (height) cm, p< 0.001. Another equation obtained predicted renal length based on body surface area (BSA): renal length = 0.8839BSA+ 8.6260, p< 0.001. Thus, patient average renal lengths increased by 0.24cm for each cm of height and 0.88cm for each unit of BSA. This study shows the values of renal sizes in Nigerians, which may be helpful in clinical settings.

Key words: Kidney dimensions, ultrasonography