FABP1 and autosomal dominant polycystic kidney disease: Although the association of urinary L-FABP with the progression of ADPKD remains unexplained, the increase in the urinary L-FABP level in patients with ADPKD, especially in those with decreased renal function, in comparison with that in healthy individuals has been reported, suggesting the association of urinary L-FABP level with ADPKD progression28.