NGAL, KIM-1 and L-FABP levels in patients with vesicoureteral reflux

Reflux nephropathy which is the most serious complication of vesicoureteral reflux (VUR) can progress to end-stage chronic renal failure. The parameters allowing early detection of kidney damage are required.The aim of this study is to assess availability of urinary levels of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and liver-type fatty acid binding protein (L-FABP), as a non-invasive marker, in early diagnosis of reflux nephropathy and follow-up in patients with VUR. In this study, 123 (36 M, 87 F; mean age 9.4 years) patients with primary VUR and 30 (10 M, 20 F; mean age 9.5 years) healthy children as a control group were ,included. Children were divided into 5 groups; Group A: patients with reflux and scar, Group B: patients with reflux and without scar, Group C: ptients with scar and resolved reflux, Group D: patients with resolved reflux and without scar, and Group E: healthy control group. Urinary levels of NGAL, KIM-1 and L-FABP measured with micro ELISA method. Urinary level of NGAL was significantly higher in patients with scar (Group A and C) than patients without scar (Group B and D) and healthy control group (p=0.0001). Urinary level of KIM-1 was similar in all groups (p=0.417). Urinary level of L-FABP was significantly higher in Group A, Group B and Group C than Group D and healthy control group (0.014). After the wxclusion of healthy controls, we analyzed our data again and found that urinary level of NGAL was significantly higher only in patients with scar (Group A and C) than patients without scar (Group B and D) (p=0.020). In conclusion, urinary level of NGAL indicates the presence of scarring in patients with VUR. We also concluded that urinary level of NGAL can be used as a non-invasive diagnostic and prognostic marker for reflux nephropathy.