Clinical value of soluble urokinase-type plasminogen activator receptor in predicting sepsis-associated acute kidney injury

Figures & data

Figure 1. Flowchart of participants included in this study.

Table 1. Baseline characteristics.

	S-AKI (n = 63)	Non-AKI (n = 116)	p Value
Baseline variables
Age (years)	61.92 ± 14.85	60.24 ± 15.86	0.490
Male/female, n (%)	45/18	84/32	0.888
ICU stay (days)	9 (4.0, 13.0)	6.0 (4.0, 11.0)	0.203
APACHE II score	19 (12, 27)	15 (11, 20)	0.014
SOFA score	5 (4, 8)	4 (3, 6)	0.003
28-d mortality, n (%)	31 (49.2%)	17 (14.7%)	< 0.001
Mechanical ventilation	56 (88.9%)	75 (64.7%)	< 0.001
Vasopressor use, n (%)	24 (38.1%)	32 (27.6%)	0.148
Renal replacement therapy, n (%)	1 (1.6%)	1 (0.9%)	0.659
Septic shock, n (%)	19 (30.2%)	26 (22.4%)	0.254
Blood culture positivity, n (%)	39 (61.9%)	46 (39.7%)	0.004
Admission after surgery, n (%)	20 (31.7%)	39 (33.6%)	0.799
Urine output	2290.0 (1597.5, 3208.8)	2485.0 (1957.5, 3367.5)	0.206
Coexisting conditions, n (%)
Hypertension	27 (42.9%)	35 (30.2%)	0.089
Coronary heart disease	7 (11.1%)	25 (21.6%)	0.083
Diabetes mellitus	10 (15.9%)	24 (20.7%)	0.434
Site of infection, n (%)
Lung	24 (38.1%)	49 (42.2%)	0.590
Abdominal	15 (23.8%)	28 (24.1%)	0.961
Urinary	2 (3.2%)	9 (7.8%)	0.223
Others	22 (34.9%)	30 (25.9%)	0.202
Blood routine parameters
WBC (10^9/L)	13.05 (7.94, 16.87)	10.64 (7.31, 15.37)	0.124
Neutrophil (10^9/L)	11.77 (6.30, 15.56)	9.41 (5.99, 13.84)	0.196
Lymphocyte (10^9/L)	0.68 (0.42, 1.13)	0.67 (0.41, 1.10)	0.693
RBC (10^12/L)	3.01 (2.64, 3.87)	3.40 (2.91, 3.82)	0.126
Platelet (10^9/L)	97.00 (58.00, 209.00)	114.5 (74.25, 210.75)	0.162
Liver parameters
ALT (U/L)	38.0 (22.2, 107.0)	32.0 (15.1, 65.8)	0.076
AST (U/L)	53.0 (29.1, 122.4)	42.7 (24.0, 82.0)	0.077
Albumin (g/L)	30.1 ± 6.2	29.0 ± 5.0	0.213
Total bilirubin (μmol/L)	23.9 (12.8, 65.4)	19.8 (11.0, 42.1)	0.123
Renal parameters
Creatinine (μmol/L)	67 (49, 84)	56 (46, 77)	0.061
BUN (mmol/L)	9.8 (6.8, 14.1)	7.3 (5.4, 10.3)	0.001
eGFR (mL/min/1.73m^2)	95.2 ± 23.7	102.2 ± 26.0	0.076
Coagulation parameters
PT (s)	15.1 (13.3, 17.7)	13.9 (12.8, 16.2)	0.014
APTT (s)	31.8 (28.6, 38.8)	30.1 (27.1, 37.2)	0.396
D-dimer (mg/L)	6.66 (2.29, 11.20)	4.03 (2.12, 8.29)	0.067
Inflammation parameters
CRP (mg/L)	116.79 (55.48, 189.62)	131.44 (82.13, 199.71)	0.241
PCT (ng/mL)	3.89 (1.30, 11.22)	5.06 (0.93, 13.66)	0.978
Blood gas parameters
pH	7.414 (7.362, 7.477)	7.444 (7.400, 7.477)	0.041
PaCO2 (mmHg)	35.6 (30.0, 43.3)	34.7 (31.2, 40.1)	0.610
PaO2 (mmHg)	98.5 (77.1, 117.2)	92.9 (74.4, 124.0)	0.579
SaO2 (mmHg)	97.0 (95.6, 98.1)	97.1 (95.1, 98.4)	0.887
Lactic acid (mmol/L)	1.81 (1.43, 2.91)	1.73 (1.33, 2.45)	0.197

AKI: acute kidney injury; ICU: intensive care unit; APACHE II: Acute Physiology and Chronic Health Evaluation; SOFA: Sequential Organ Failure Assessment; WBC: white blood cell; RBC; red blood cell; ALT: alanine aminotransferase; AST: aspartate aminotransferase; BUN: blood urea nitrogen; eGFR: estimated glomerular filtration rate; PT: prothrombin time; APTT: Activated partial thrombin time; CRP: C-reactive protein; PCT: procalcitonin

Bolded values represent values with p < 0.05.

Table 2. Comparison of suPAR levels between S-AKI and non-AKI groups at four time-points after sepsis diagnosis.

suPAR (ng/mL)
Time after sepsis diagnosis (h)	S-AKI (n = 63)	Non-AKI (n = 116)	Z/t value	p Value
0	5.91 (4.14, 8.57)	5.55 (3.78, 7.43)	−0.401	0.688
12	6.69 ± 2.18	5.26 ± 2.15	4.234	<0.001
24	6.72 (5.11, 8.89)	4.83 (3.55, 6.55)	−2.893	0.004
48	6.22 (4.73, 8.51)	4.68 (3.08, 6.57)	−2.187	0.029

suPAR: soluble urokinase-type plasminogen activator receptor; S-AKI: sepsis-associated acute kidney injury; non-AKI: non-acute kidney injury

Bolded values represent values with p < 0.05.

Figure 2. The receiver operating characteristic curve of suPAR for predicting sepsis-associated acute kidney injury (S-AKI) in patients with sepsis.

Table 3. Receiver operating characteristic analysis for predicting S-AKI based on the suPAR level.

Time after sepsis diagnosis	Patients(n)	S-AKI (n)	AUC	p	95%CI	Cutoff	Sensitivity	Specificity
0 h	179	63	0.547	0.295	0.456–0.638	–	–	–
12 h	179	63	0.681	<0.001	0.601–0.760	5.56 ng/mL	71.4%	58.6%
24 h	179	63	0.700	<0.001	0.621–0.779	6.31 ng/mL	61.9%	71.6%
48 h	179	63	0.671	<0.001	0.591–0.751	4.72 ng/mL	76.2%	51.7%

suPAR: soluble urokinase-type plasminogen activator receptor; S-AKI: sepsis-associated acute kidney injury; AUC: area under the curve; CI: confidence interval

Table 4. Logistic regression analysis of the risk factors for S-AKI.

Variables	Univariate analysis
	B	SE	Wald	OR	95%CI	p Value
APACHE II score	0.060	0.021	8.418	1.062	1.020–1.105	0.004
SOFA score	0.152	0.055	7.491	1.164	1.044–1.298	0.006
Mechanical ventilation	1.476	0.445	10.972	4.373	1.827–10.471	0.001
BUN (mmol/L)	0.119	0.034	12.198	1.127	1.054–1.205	<0.001
PT (s)	<0.001	0.013	<0.001	1.000	0.974–1.027	0.983
pH	−3.904	1.739	5.049	0.020	0.001–0.607	0.020
24-h suPAR	0.315	0.075	17.677	1.371	1.183–1.588	<0.001
Variables	Multivariate analysis
	B	SE	Wald	OR	95%CI	p Value
Mechanical ventilation	1.491	0.498	8.961	4.441	1.673–11.786	0.003
BUN (mmol/L)	0.071	0.034	4.232	1.073	1.003–1.148	0.040
pH	−3.401	1.770	3.694	0.033	0.001–1.070	0.055
24-h suPAR	0.311	0.084	13.678	1.364	1.157–1.608	<0.001

S-AKI: sepsis-associated acute kidney injury; SE: standard error; OR: odds ratio; CI: confidence interval; APACHE II: Acute Physiology and Chronic Health Evaluation; SOFA: Sequential Organ Failure Assessment; BUN: blood urea nitrogen; PT: prothrombin time; suPAR: soluble urokinase-type plasminogen activator receptor