Relationship between peripheral blood endotoxin, toll-like receptor 4 expression, and postoperative infection following surgery for acute appendicitis

Table 1 Comparison of general characteristics, mean ± SD or n

Index	Infected group (n = 36)	Uninfected group (n = 117)	t/χ2	P value
Sex			0.224	0.636
Male	21	63
Female	15	54
Age, years	38.36 ± 7.19	39.01 ± 6.71	0.498	0.619
Pathological type1			7.136	0.008
Uncomplicated	2	31
Purulent or gangrenous	34	86
Operation method1			4.366	0.037
Traditional open surgery	34	93
Laparoscopic surgery	2	24
Surgery time, minutes2	59.96 ± 7.41	51.91 ± 6.32	6.417	< 0.001
Incision length, cm1	5.36 ± 1.26	4.78 ± 0.99	2.890	0.004
White blood cell count, × 109/L	8.54 ± 1.03	8.35 ± 1.31	0.800	0.425
Neutrophil count, %	59.75 ± 10.30	56.40 ± 9.72	1.783	0.077
CRP, mg/L	18.31 ± 3.14	19.41 ± 4.03	1.502	0.135
Diabetes	10	32	0.003	0.960
Hypertension	8	27	0.011	0.915

¹P < 0.05, χ²-test.

²P < 0.05, t-test.

CRP: C-reactive protein.

Table 2 Non-conditional logistic regression analysis of risk factors of postoperative incision infection in patients

Factor	B	SE	Exp (B)	Wald	Sig
Pathological type	2.243	0.842	9.419 (1.809-49.051)	7.097	0.008
Operation method	1.859	0.851	6.418 (1.210-34.037)	4.770	0.029
Surgery time	0.190	0.042	1.209 (1.114-1.312)	20.805	< 0.001
Incision length	0.470	0.232	1.601 (1.016-2.521)	4.117	0.042
Constant	-21.780	4.041	-	29.051	< 0.001

Table 3 Comparison of laboratory data between two groups, mean ± SD

Group	ETX (EU/mL)	TLR4 (ng/mL)
Infected group (n = 36)	0.36 ± 0.13	3.00 ± 0.83
Uninfected group (n = 117)	0.20 ± 0.06	2.17 ± 0.70
T	10.207	5.953
P value	< 0.001	< 0.001

ETX: Endotoxin; TLR4: Toll-like receptor 4.

Table 4 Predictive value of peripheral blood endotoxin, toll-like receptor 4 expression for postoperative incision infection

Index	Cutoff value	AUC	95%CI	P value	Sensitivity, %	Specificity, %
ETX	0.31	0.841	0.743-0.939	< 0.001	72.22	94.85
TLR4	2.94	0.769	0.679-0.858	< 0.001	52.84	88.00
Joint detection	-	0.922	0.873-0.972	< 0.001	86.11	85.54

AUC: Area under the curve; CI: Confidence interval; ETX: Endotoxin; TLR4: Toll-like receptor 4.