Thickness of Subcutaneous Fat Is a Predictive Factor of Incisional Surgical Site Infection in Crohn’s Disease Surgery: A Retrospective Study

Abstract

Background Incisional surgical site infection (iSSI) is a frequent postoperative complication of abdominal surgeries in patients with Crohn's disease (CD). In this study, we investigated the association between thickness of subcutaneous fat (TSF) and iSSI in patients with CD undergoing intestinal resections. Patients and Methods Patients with CD who had undergone abdominal surgery from January 2014 to January 2017 were included in this retrospective study. Patients' TSF and other possible predictors of iSSI, including clinical characteristics, preoperative medications, hematological index, surgery-related data, and postoperative outcomes, were collected. Univariate and multivariate statistical analyses were used to examine the potential factors. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive value of factors. Results The patient cohort comprised 246 patients (167 male (67.9%); mean age 35.7 ± 12.4 years; mean disease duration 69.6 ± 60.8 months). The incidence of iSSI was 24.8% (61/246). TSF was a significant predictor of iSSI (OR 1.079, 95% CIs (1.020, 1.142), P = 0.008), being 13.7 mm in patients with iSSI and 9.9 mm in those without iSSI (P < 0.001). Additionally, C-reactive protein (CRP) concentrations (OR 1.059, P = 0.003) were also possible predictors of iSSI, as indicated by both univariate and multivariate analysis. A model of iSSI comprising TSF and CRP concentrations was moderately accurate (AUC 0.827, CIs (0.766, 0.888)). Conclusions Preoperative TSF and CRP independently affect iSSI in patients with CD undergoing intestinal resections.

Thickness of subcutaneous fat is a risk factor for incisional surgical site infection in acute appendicitis surgery: a prospective study

“…Second, we found that TSF is a predictor for incisional SSI in patients undergoing open appendectomy. This finding confirms what other studies have shown that TSF was independently associated with SSI in a variety of surgical procedures, including Crohn's disease surgery, elective colorectal surgery, abdominal hysterectomy, and cervical spine fusion surgery [14,15,24,25]. In our study, BMI was shown to be linearly related with TSF as evidenced by multicollinearity.…”

“…However, other study has reported a markedly lower cut-off TSF value of 10.2 mm for patients undergoing Crohn's disease surgery [14]. This difference can be explained as Crohn's disease is a type of wasting disease and thus differs from other diseases [14]. This highlights the need for a differential cut-off value for TSF depending on diseases involved.…”

“…Similarly, two studies reported cut-off value for TSF of 20 mm and 30 mm for patients who developed incisional SSI after undergoing elective colorectal surgery and abdominal hysterectomy, respectively [15,25]. However, other study has reported a markedly lower cut-off TSF value of 10.2 mm for patients undergoing Crohn's disease surgery [14]. This difference can be explained as Crohn's disease is a type of wasting disease and thus differs from other diseases [14].…”

“…However, BMI has increasingly been recognized as a rather poor indicator of percent of body fat and does not capture on distribution of fat in the body [26]. Indeed, several studies did not find association between BMI and SSI [14,15,24,27], thus showing a mixed result whether BMI measurement can provide utility in predicting wound infection risk after surgery. Our study indicates that TSF can be a more useful indicator in predicting incisional SSI rather than BMI.…”

“…Several studies have reported TSF as an independent risk factor of incisional SSI in colorectal surgery [14,15]. In these retrospective studies, preoperative TSF was evaluated using computed tomography (CT) scan.…”