Table 4.

Comparison between patients with transient versus persistent AKI

Characteristics of Patients	Transient AKI (n = 4)	Persistent AKI (n = 51)	P-value
SCr (µmol/L) at admission, mean ± SD)	87 ± 27	116 ± 106	0.16
SCr (µmol/L) at AKI, mean ± SD)	81 ± 36	147 ± 109	0.02
SCr (µmol/L) 48h after AKI, mean ± SD)	69 ± 29	196 ± 226	<0.001
Defined using SCr criteria, n (%) Defined using diuresis criteria, n (%)	1/4 (25) 3/4 (75)	46/51 (90) 25/51 (49)	0.14
AKI Stage 1, n (%)	1/4 (25)	20/51 (39)	0.18
AKI Stage 2, n (%)	3/4 (75)	16/51 (31)
AKI Stage 3, n (%)	0	15/51 (30)
Fluid balance 48 h after AKI (mL), mean ± SD	6146 ± 2519	8767 ± 4429	0.36
Fluid balance 72 h after AKI (mL), mean ± SD	8070 ± 3732	12 805 ± 6378	0.29
Minimum diuresis (mL/kg/h), mean ± SD	0.6 ± 0.2	0.5 ± 0.3	0.67
Urinary Na+ (mmol/L), mean ± SD	81 ± 75	53 ± 40	0.52
Urinary K+ (mmol/L), mean ± SD	34 ± 22	44 ± 21	0.46
Urinary urea (mmol/L), mean ± SD	291 ± 80	327 ± 164	0.69
Urinary osmolarity (mmol/L), mean ± SD	637 ± 330	515 ± 182	0.52
FeNa+ (%), mean ± SD	0.6 ± 0.7	0.6 ± 0.9	0.96
FeUrea (%), mean ± SD	39 ± 11	33 ± 12	0.35
UNa+/UK+ ratio, mean ± SD	2.3 ± 1.6	1.7 ± 2	0.54
Proteinuria/creatininuria (mg/mmol), median (IQR)	124 (38–203)	82 (54–140)	0.62
Albuminuria/creatininuria (mg/mmol), median (IQR)	6 (6–8)	9 (5–32)	0.31
Albuminuria/proteinuria (%), mean ± SD	8 ± 6	23 ± 20	0.03
Haematuria, n (%)	3/4 (75)	35/51 (69)	1
Leucocyturia, n (%)	1/4 (25)	24/51 (47)	0.62
Glycosuria, n (%)	0 (0)	2/51 (4)	1
RRT, n (%)	NR	10/51 (20)	NA
Date of RRT initiation, median (IQR)	NR	8 (4–10)	NA
Indication of RRT initiation, n (%)	NR	N = 10	NA
Anuria ≥72h		7/10 (70)
[K+] >6 mmol/L		1/10 (10)
pH <7.15		2/10 (20)
Acute pulmonary oedema		0 (0)
Death, n (%)	0 (0)	2/51 (4)	1

Fe, fractional excretion; K⁺, potassium; Na⁺, sodium; NA, not available; NR, not relevant; UNa⁺/K⁺ ratio, urinary sodium/potassium ratio.