Reference values for glomerular filtration rate in patients with solitary kidney and multifactor analysis

Objective: To establish the GFR reference range of solitary kidney by ⁹⁹Tc^m-DTPA SPECT imaging and explore factors influencing renal compensation. Methods: A total of 108 patients (62 males, 46 females, age range: 5-83 (47 ± 19) years) with only one functional kidney who underwent ⁹⁹Tc^m-DTPA dynamic imaging from January 2011 to September 2015 were retrospectively analyzed. The GFR was measured to establish the reference range. Meanwhile, the potential influence factors were analyzed, including age, gender, location of the functional kidney, removal and causes of the non-functional kidney. Two-sample t test, one-way analysis of variance and Bonferroni test were used. Results: The GFR were (71.81± 23.23) ml/min in the 108 patients. There were no significant differences of GFR between male and female patients (t = 0.496), between patients with left functional kidney and those with right functional kidney(t = 0.999), between patients with and without removed non-function kidney(t = -1.966), and among patients with different causes of the non-function kidney(F =1.894; all P > 0.05). The GFR was significant different in different groups based on age(F = 13.924, P < 0.001). There was a negative correlation between the GFR and age(r = -0.570, P < 0.001). The GFR CF in different age groups (≤20 years, 20 years < age ≤ 40 years, 40 years 60 years) were 37.6%, 26.7%, 21.3%, 30.1%, respectively. Conclusions: It is objective and efficient to assess the renal compensation by establishing the reference values for GFR of the solitary kidney. There is a negative correlation between age and renal compensation, and the variation of renal compensation is larger in younger patients. (authors)