A Systematic Review on Sonographic Evaluation of Renal Size in Apparently Healthy Adults

Abstract

The normal size of a kidney is variable and is affected by both physiologic and pathological conditions. Since renal size is affected by various factors, it is necessary to establish population specific normative values. Ultrasonography has shown its usefulness as an essential tool in the evaluation of renal size. The study aimed at reviewing published articles in the evaluation of renal size and identifying gaps in order to make recommendation for further studies. All articles included in this review are prospective in design with the smallest sample size used being 100 participants and the largest 4,035 participants. The age of the participants ranged from 13 to 80 years. The overall mean renal size reported in this review ranged from 63±18.1 cm3 to 164.3±38 cm3 for the right kidney and 69.1±25.1 cm3 to 183.3±48.9 cm3 for the left kidney. Six of the reviewed articles reported a statistical significant difference between male and female mean renal size (p<0.05), while two articles revealed no statistical significant difference between male and female mean renal sizes (p>0.05). However, the remaining seven articles did not compare the mean renal size between male and female participants. Seven out of the articles reported a significant positive correlation between kidney dimensions and BMI, while other eight articles did not check the association between kidney dimensions and anthropometric parameters. This review showed only one article out of fifteen used a probability sampling method and only two articles used larger sample size. Eight of the reviewed articles did not perform creatinine clearance test before recruitment of their participants.