Clinical assessment of neutrophil gelatinase-associated lipocalin as a potential diagnostic marker for neonatal sepsis: a prospective cohort study

Figures & data

Figure 1. Cases selection criteria.

Table 1. Demographic and clinical characteristics of the studied groups.

Variables	Cases (n = 30 neonates)	Control (n = 30 neonates)	P-value
Gestational age (weeks)	36 (35.0 to 37.0)	36 (35.7 to 37.0)	.557
Mode of delivery
Cesarean section	16 (53.3%)	22 (73.3%)	.108
Normal vaginal delivery	14 (46.7%)	8 (26.7%)
Gender
Male	16 (53.3%)	13 (43.3%)	.438
Female	14 (46.7)	17 (56.7%)	–
Age (days)	1.0 (1.0 to 4.0)	2.0 (1.75 to 3.00)	.478
Weight (Kg)	2.81 ± 0.44	3.0 ± 0.28	.039^a
Creatinine(mg/dl)	1.13 ± 0.32	0.6 ± 0.24	<.001^a
Urea (mg/dl)	49.81 ± 6.18	23.8 ± 4.15	<.001^a
Na+ (mEq/l)	135.81 ± 6.09	136.8 ± 6.81	<.001^a
K+ (mEq/l)	4.54 ± 0.84	3.91 ± 0.38	<.001^a
Total leucocyte count (×10^3/µl)	13.70 (7.90 to 26.56)	8.15 (7.80 to 8.30)	.002^a
Haemoglobin (g%)	12.8 ± 2.25	15.4 ± 0.89	˂.001^a
Platelet (×10^3/µl)	160..57 ± 74.86	257.13 ± 38.5	˂.001^a
C-reactive protein, mg/l	14.0 (5.75 to 24.25)	4.0 (3 to 6)	˂.001^a
NGAL (pg/ml)	1428 ± 440.8	239.17 ± 32.4	˂.001^a
Non-survivors	13 (43.3%)	–	–
Complications
Disseminated intravascular coagulation	4 (13.3%)	–	–
Heart failure	2 (6.6%)	–	–
Inter-ventricular haemorrhage	1 (3.3)	–	–
Necrotizing enterocolitis	3 (10%)	–	–
Pneumonia	5 (16.6)	–	–
Septic Shock	2 (6.6%)	–	–

Parametric data are expressed as mean ± SD, and non-parametric data are expressed as median (interquartile range). Qualitative data are expressed as frequency (percentage).

NGAL: Neutrophil Gelatinase-associated Lipocalin

^ap< .05 is significant.

Table 2. Clinical characteristics among the survived and non-survived cases.

Variables	Survivors	Non-survivors	P-value
	(n = 17 neonates)	(n = 13 neonates)
Total leucocyte count (×10)^3/µl	8.2 (6.65 to 11.8)	26.8 (18.95 to 29.35)	˂.001^a
Haemoglobin (g%)	14.25 ± 1.82	10.9 ± 0.99	˂.001^a
Platelets (×10^3/µl)	203.3 ± 57.5	104.67 ± 56.2	˂.001^a
C-reactive protein at 0 h, mg/l	6.0 (5.0 to 11.5)	25.0 (17.5 to 29.5)	˂.001^a
C-reactive protein after 96 h, mg/l	10.0 (3.0 to 31.5)	120 (58.5 to 163.5)	˂.001^a
NGAL at 0 h, pg/ml	1382 ± 141	1489 ± 660	.574
NGAL after 96 h, pg/ml	600 (562.5 to 625.0)	3000 (1725 to 3175)	˂.001^a
Clinical Sepsis Score (CSS)	3.0 (2.0 to 4.0)	6.0 (4.5 to 6.0)	˂.001^a
Hematological Sepsis Score (HSS)	3.0 (2.0 to 4.0)	6.0 (4.5 to 6.0)	˂.001^a

Data are expressed as mean ± SD for Gaussian data and median (interquartile range) for non-Gaussian data.

NGAL: Neutrophil Gelatinase-associated Lipocalin

^ap< .05 is significant.

Table 3. Correlation analysis between the NGAL levels of the entire cohort at 0 h, septic cases at 96hs and other different parameters.

	NGAL at 0 h (pg/ml)		NGAL after 96 h (pg/ml)
	Coefficient	P-value	Coefficient	P-value
Weight (Kg)	−0.072	.706	−0.453	.012^a
Creatinine (mg/dl)	0.053	.512	0.061	.542
Urea (mg/dl)	0.081	.632	0.21	.534
Total leucocyte count (×10)^3/µl	0.417	.022^a	0.88	<.001^a
Haemoglobin (g%)	−0.19	.316	−0.684	<.001^a
Platelets (×10)^3/µl	−0.258	.169	−0.682	<.001^a
C-reactive protein at 0 h, mg/l	0.472	.009^a	0.925	<.001^a
C-reactive protein after 96 h, mg/l	–	–	0.848	<.001^a
Clinical sepsis score	0.458	.011^a	0.952	<.001^a
Hematological Sepsis Score	0.507	<.004^a	0.917	<.001^a

NGAL: Neutrophil gelatinase-associated Lipocalin

^ap< .05 is significant.

Figure 2. Receiver-operating characteristic (ROC) curve of (A) NGAL, CRP, and TLC; (B) haemoglobin and platelets for discrimination between septic patients and controls. CRP: C-reactive protein; NGAL: Neutrophil gelatinase-associated lipocalin; Plat: platelets; TLC: Total leucocyte count.

Table 4. Diagnostic performance of NGAL and other studied parameters as diagnostic markers for neonatal sepsis.

	Area under the curve	95% Confidence Interval		Cut-off		Sensitivity (%)	Specificity (%)
		Lower bound	Upper bound
NGAL, pg/ml	1	1	1	475		100.00%	100.00%
C-reactive protein, mg/l	0.869	0.775	0.964	10.5		66.70%	100.00%
Total leucocyte count (×10)3/µl	0.736	0.592	0.879	10.55		63.30%	100.00%
Haemoglobin (g%)	0.829	0.713	0.945	14.35		73.30%	93.30%
Platelet (×10)3/µl	0.867	0.76	0.974	215		80.00%	96.70%

NGAL: Neutrophil gelatinase-associated Lipocalin.

Data availability statement

Data are available upon reasonable request by contacting the corresponding author.