Urine liver fatty acid binding protein and chronic kidney disease progression

Abstract

Excretion of the tubular protein liver fatty acid binding protein (L-FABP) is a potential novel biomarker of renal dysfunction. We examined whether urine L-FABP excretion adds prognostic information to the well-established risk markers, blood pressure (BP), albumin excretion and baseline GFR, regarding progression of chronic kidney disease (CKD). In a prospective study design a cohort of 74 stage 3-4 CKD patients (age 61 ± 13 years) were included. Glomerular filtration ratio (GFR, Cr-EDTA-clearance), 24-hour ambulatory BP, 24-hour urinary albumin/creatinine ratio (UAC) and urinary L-FABP/creatinine ratio (U-L-FABP/C) weredetermined at baseline and after 18 months of follow-up. For comparison 25 age-matched healthy controls were included. The U-L-FABP/C was elevated in CKD patients when compared to controls (mean U-L-FABP/C 2.3 [95% CI 1.7-2.9] μg/mmol vs 0.6 [0.5-0.7] μg/mmol, p < .001). In CKD patients, log U-L-FABP/C at baseline and at follow-up were positively associated (Pearson correlation coefficient r = 0.74, p < .001). Baseline log U-L-FABP/C was negatively correlated with baseline GFR (r = -0.32, p < .001) and directly correlated with UAC (r = 0.67, p < .001). The relative change in GFR from baseline to follow-up correlated with baseline UAC (p < .001), 24-hour systolic BP (p = 0.05) and log U-L-FABP/C (p < .001). Using multiple regression analysis adjusting for baseline GFR, UAC, BP, age and gender, baseline log U-L-FABP/C was associated with a decline in GFR only in patients with UAC <3 mg/mmol (n = 29, p = 0.001) and not in patients with UAC ≥3 mg/mmol (n = 44, p = 0.21). In conclusion urine L-FABP/C is permanently elevated in CKD patients, but only associated with GFR decline in those without albuminuria.

Evaluation of liver-type fatty acid binding protein (L-FABP) and interleukin 6 in children with renal cysts

“…Evaluation of the correlation between the tested markers and biochemical parameters and blood pressure values concentration in the urine correlates with the loss of renal function only in the absence of significant albuminuria. 33 Matsui et al followed 244 adult CKD patients for 3 years and confirmed that elevated urinary L-FABP concentration was associated with progression to ESRD and the incidence of severe cardiovascular events in these patients. 34 In literature, no one before conducted research on the evaluation of L-FABP in a selected group of children with cystic kidney disease, nor did anyone make comparisons between groups of children with single and multiple renal cysts.…”

Changing Trends in Lipid Profile and Biomarkers of Renal Function and Bone Metabolism Before and After Switching From Tenofovir Disoproxil Fumarate to Tenofovir Alafenamide: a Prospective Observational Study

“…Because L-FABP was reported as a potential marker of CKD for patients without albuminuria (16), the detection of subclinical changes using urinary L-FABP prior to the progression to CKD is important in patients taking TAF, especially in those with low body weight.…”

A review of urinary angiotensin converting enzyme 2 in diabetes and diabetic nephropathy

“…Urine albumin is currently used in diagnosis and prognosis diabetic nephropathy while urinary nephrin and L-FABP are indicators of glomerular and tubulointerstial injury that occurs in the early stages of kidney disease. Like urinary ACE2, both nephrin and L-FABP were significantly increased among normoalbuminuric patients, positively correlated with proximal tubular dysfunction and negatively associated with eGFR ( 14 , 37 , 38 ). These observations suggest that urinary ACE2 rises in early stages of diabetes and could reflect the state of kidney function, an attribute of a good diagnostic and prognostic biomarker.…”