Assessment of normal renal size in healthy individuals in Pakistan and its influencing factors: A cross-sectional study

Background and objectives. In order to address the need to establish normative benchmark of kidney size in healthy population of Pakistan, this study aimed to assess and quantify the renal sizes in healthy individuals within the Pakistani population using ultrasound imaging. Secondary objectives included examining age-related variations, gender-specific differences, and the correlation between Body Mass Index (BMI) and kidney measurements. Materials and methods. A five-year retrospective investigation of 509 patients undergoing non-renal abdominal ultrasounds at NIKUD Research Hospital employed strict participant criteria, excluding those with diabetes, hypertension, abnormal eGFR, or urinalysis. Ultrasound data was collected from medical record of patients aged 18-80 years without a history or ongoing renal disease, excluding any conditions impacting renal size. Results. In 480 participants meeting stringent health criteria, the right kidney measured 10.45 ± 0.97 cm, and the left kidney measured 10.64 ± 0.95 cm. Age-related variations included increasing renal length until the fifth decade, followed by decline. Gender-specific differences, though statistically non-significant, suggested slightly larger renal sizes in females. A positive BMI and renal length relationship indicated increased sizes in obese individuals. Conclusions. This study establishes renal size benchmarks in a healthy Pakistani population, highlighting demographic factors' role in assessments. Variations across age, gender, and BMI underscore the need for population-specific norms in clinical evaluations.