KL and diabetic kidney disease: We measured the urinary levels of α-klotho with single random spot urine samples, although urine samples were collected at the outpatient clinic from patients without illness or renal diseases besides diabetic nephropathy; moreover, a moderate linear association was observed between the amount of urine α-klotho in 24 hours and urinary α-klotho/creatinine ratio in random urine specimens (r = 0.726, p<0.01) [5].