Combination of early Interleukin-6 and -18 levels predicts postoperative nosocomial infection

Application value of combined detection of serum IL-6, SDF-1 and CD64 in the diagnosis of early postoperative infection after limb fractures

OBJECTIVE

To explore the application value of combined detection of serum interleukin-6 (IL-6), stromal cell-derived factor-1 (SDF-1) and neutrophils CD64 (CD64) in the diagnosis of early postoperative infection after limb fractures.

METHODS

419 patients with limb fractures un erwent surgical treatment in our hospital were selected as study subjects, and they were divided into infection group (n = 104) and non-infection group (n = 315) according to postoperative pathological results of puncture to detect the levels of serum IL-6, SDF-1 and CD64 in the two groups on the 1st, 3rd, 5th and 7th day after surgery, and to analyze the clinical diagnostic efficacy of single and combined detection of the three indexes in early postoperative infection after limb fractures by ROC curve.

RESULTS

The levels of serum IL-6, SDF-1 and CD64 in infection group were overtly higher than those in non-infection group at different time after surgery (P < 0.05), and the AUC value, specificity and sensitivity of combined detection were higher than those of single diagnosis. In this study, 14 patients in infection group underwent reoperation, 22 patients received conservative treatment in the later period, 6 patients had postoperative muscular dystrophy, and the remaining patients had a good prognosis.

CONCLUSION

Serum IL-6, SDF-1 and CD64 are closely related to the occurrence of early postoperative infection after limb fractures, and their combination is helpful to improve diagnostic accuracy of early postoperative infection and provide effective reference value for the treatment of postoperative infection in orthopedics.

Measuring serum and drainage fluid interleukin-6 and tumor necrosis factor-α levels for early detection of infectious complications after minimally invasive surgery for gastric cancer

OBJECTIVE

Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are inflammatory cytokines produced in response to biological invasion or infection. Their levels are elevated in the blood and locally. We examined whether measuring IL-6 and TNF-α levels in serum or drainage fluid on postoperative day (POD) 1 could detect infectious complications after minimally invasive surgery for gastric cancer.

METHODS

This cohort study included 205 consecutive patients who underwent laparoscopic or robot-assisted gastrectomy for gastric cancer between November 2020 and July 2023. We measured serum and drainage fluid IL-6 and TNF-α levels on POD 1 after gastrectomy. Receiver operating characteristic (ROC) curves were created to compare the diagnostic values of each cytokine and serum C-reactive protein levels for detecting postoperative infectious complications.

RESULTS

IL-6 and TNF-α levels in the serum or drainage fluid were significantly higher in patients with an infectious complication. In addition, drainage fluid IL-6 levels were significantly different in patients with versus without intra-abdominal abscess. In the ROC curve analysis, serum and drainage fluid IL-6 had the highest AUC values for any infectious complication and intra-abdominal abscess, respectively. POD 1 serum IL-6 level above 47 pg/mL could detect any infectious complication with sensitivity of 74.1 % and specificity of 71.8 %. POD 1 drainage fluid IL-6 level above 14,750 pg/mL had 100 % sensitivity for detecting intra-abdominal abscess with specificity of 56.0 %.

CONCLUSIONS

Measurement of IL-6 levels in blood and drainage fluid on POD 1 is valuable for early detection of postoperative infectious complications or intra-abdominal abscess after gastric cancer surgery.

Interleukin-6 on postoperative day three as an early predictor of infections following laparoscopic gastric cancer resection

BACKGROUND

To investigate the role of C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6) as early predictors of infectious complications after laparoscopic gastric cancer surgery.

METHODS

Patients who underwent laparoscopic gastric cancer surgery between January 2020 and June 2022 were retrospectively enrolled. IL-6, PCT, and CRP levels were assessed before surgery and on postoperative days (PODs) 3 and 5. Differences in serum IL-6, PCT, and CRP levels between the infected and non-infected groups were compared. The diagnostic accuracy was determined using the area under the receiver operating characteristic curve (AUC).

RESULTS

A total of 206 patients were enrolled, and 21 patients (10.19%) developed postoperative infections. Serum IL-6, PCT, and CRP levels in the infected group were significantly higher than those in the non-infected group on PODs 3 and 5. IL-6 with an optimal cutoff value of 84.00 pg/mL (AUC 0.84), PCT with an optimal cutoff value of 1.39 ng/mL (AUC 0.80), CRP with an optimal cutoff value of 150.00 mg/L (AUC 0.76) on POD 3 had superior diagnostic accuracy in predicting postoperative infections. Multivariate analysis identified PCT and IL-6 levels on POD 3 as independent risk factors, the AUC of the combination of IL-6 and PCT was 0.89. The Delong test showed no difference between the AUC of IL-6 alone and IL-6 combined with PCT prediction (P = 0.07, Z = 1.81).

CONCLUSIONS

IL-6 level on POD 3 is an excellent predictor of infectious complications following laparoscopic gastric cancer surgery. Patients with IL-6 levels lower than 84.00 pg/mL on POD 3 can ensure safe early discharge with a low probability of infection.