Table 2.

Patient characteristics of the KIdney of MONofunctional Origin (KIMONO) study cohort

CharacteristicSFKCongenital SFKAcquired SFKP Value
Patients, n (%)77 (100)26 (34)51 (66)
Male, n (%)48 (62)20 (77)28 (55)0.06
Median age (yr)14.6 (10.4–17.6)13.7 (10.4–17.4)15.7 (10.3–17.5)0.46
Height SD score−0.7±1.2−0.5±1.2−0.8±1.20.25
Weight SD score0.1±1.60.2±1.70.1±1.60.70
Body mass index SD score0.6±1.50.5±1.40.6±1.60.34
Body surface area (m2)1.5±0.41.5±0.41.5±0.40.94
Renal variables
 Median serum creatinine (mg/dl)0.81 (0.63–0.97)0.67 (0.56–0.95)0.85 (0.70–1.04)0.18
 Median serum cystatin C (mg/l)0.88 (0.81–1.06)0.89 (0.76–0.96)0.88 (0.82–1.07)0.81
 Median BUN (mg/dl)14.6 (12.0–17.1)14.0 (10.8–16.7)14.8 (12.0–17.1)0.45
 GFR-inulin (ml/min per 1.73 m2)82±2485±2381±250.43
 eGFR-Schwartz (ml/min per 1.73 m2)82±2790±2778±260.07
 Ccreat (ml/min per 1.73 m2)112±46128±50104±420.03
 eGFR-Zappitelli1 (ml/min per 1.73 m2)85±2488±2683±240.45
 eGFR-Zappitelli2 (ml/min per 1.73 m2)85±2692±2882±240.27
 eGFR-CKiD1 (ml/min per 1.73 m2)80±2082±2179±200.46
 eGFR-CKiD2 (ml/min per 1.73 m2)83±2290±2380±210.05
 CKD stage 2 or higher, n (%)a44 (57)15 (58)29 (57)0.73
 Increased serum cystatin C, n (%)27 (35)8 (31)19 (37)0.57
  • Median values are expressed with interquartile ranges. Data expressed with a plus/minus sign are the mean ± SD. P values represent differences between congenital SFK and acquired SFK. SFK, solitary functioning kidney; GFR-inulin, GFR based on inulin single-injection method; eGFR-Schwartz, estimated GFR based on serum creatinine; Ccreat, urinary creatinine clearance; eGFR-Zappitelli1, estimated GFR based on serum cystatin C; eGFR-Zappitelli2, estimated GFR based on serum cystatin C and creatinine; eGFR-CKiD [Chronic Kidney Disease in Children] 1, estimated GFR based on serum cystatin C; eGFR-CKiD2, estimated GFR based on serum cystatin C, creatinine, and BUN.

  • a Based on GFR-inulin.