Table 2.

Performance of usual urinary markers for detecting patients with persistent AKI among patients with AKI, with the usual and optimal (*) cutoff values^a

Patient groups	FeNa > 1%	FeNa* > 0.58%	FeUrea < 35%	FeUrea* < 37%	U/P urea < 10	U/P urea* < 12	U/P creat < 20	U/P creat* < 12
All patients with AKI (n = 136; persistent AKI prevalence = 60.3%)
Sensitivity (%)	0.48	0.63	0.63	0.66	0.74	0.66	0.79	0.59
Specificity (%)	0.7	0.61	0.54	0.53	0.57	0.66	0.39	0.59
Positive predictive value	0.71	0.71	0.67	0.68	0.72	0.74	0.66	0.68
Negative predictive value	0.47	0.47	0.47	0.51	0.59	0.56	0.55	0.48
Positive likelihood ratio	1.6	1.61	1.37	1.4	1.72	1.94	1.3	1.44
Negative likelihood ratio	0.74	0.61	0.68	0.64	0.45	0.52	0.54	0.69
Younden's index	0.18	0.24	0.17	0.19	0.31	0.32	0.18	0.18
ROC AUC	0.62 (0.52 to 0.72)		0.59 (0.49 to 0.70)		0.71 (0.62 to 0.80)		0.62 (0.53 to 0.72)
Patients taking diuretics (n = 50; persistent AKI prevalence = 64%)
Sensitivity (%)	0.75	0.62	0.61	0.61	0.72	0.61	0.78	0.89
Specificity (%)	0.56	0.56	0.47	0.59	0.69	0.75	0.5	0.38
Positive predictive value	0.71	0.71	0.67	0.68	0.81	0.81	0.73	0.72
Negative predictive value	0.47	0.47	0.49	0.51	0.58	0.52	0.56	0.66
Positive likelihood ratio	1.7	1.41	1.15	1.49	2.32	2.44	1.56	1.44
Negative likelihood ratio	0.47	0.68	0.83	0.66	0.41	0.52	0.44	0.29
Younden's index	0.31	0.18	0.08	0.2	0.41	0.36	0.28	0.27
ROC AUC	0.69 (0.54 to 0.81)		0.58 (0.41 to 0.75)		0.82 (0.70 to 0.94)		0.71 (0.56 to 0.86)
Patients with sepsis (n = 94; persistent AKI prevalence = 65%)
Sensitivity (%)	0.5	0.65	0.63	0.63	0.8	0.67	0.87	0.93
Specificity (%)	0.86	0.56	0.52	0.57	0.63	0.63	0.42	0.37
Positive predictive value	0.87	0.73	0.71	0.73	0.8	0.63	0.74	0.73
Negative predictive value	0.48	0.46	0.43	0.45	0.63	0.51	0.63	0.74
Positive likelihood ratio	3.57	1.48	1.31	1.47	2.1	1.81	1.5	1.48
Negative likelihood ratio	0.58	0.63	0.71	0.65	0.32	0.52	0.31	0.19
Younden's index	0.36	0.19	0.15	0.2	0.43	0.3	0.29	0.3
ROC AUC	0.67 (0.56 to 0.79)		0.56 (0.43 to 0.68)		0.71 (0.60 to 0.82)		0.65 (0.53 to 0.77)

^aAKI: acute kidney injury; ROC: receiver operating characteristic; AUC: area under the curve.