ObjectiveTo investigate the clinical values of serum histidine decarboxylase (HDC), D-lactate, and alpha-glutathione S-transferase (α-GST) for diagnosing intestinal mucosal injury of patients with intestinal obstruction. MethodsThe expression levels of serum HDC, D-lactate, and α-GST in 28 patients with strangulated intestinal obstruction, 19 patients with simple intestinal obstruction, 17 patients with acute simple appendicitis, and 20 healthy volunteers were determined by enzyme linked immunosorbent assay (ELISA) before the treatment, and then the area under receiver operating characteristic curve (AUC) of these diagnostic indices were compared. In addition, the occurrence rates of systemic inflammatory response syndrome (SIRS) and infectious complications (abdominal cavity infection and pulmonary infection) were closely observed. The relevances of SIRS and infectious complications and the expression levels of these three diagnostic indices were analyzed. ResultsThe expression levels of serum HDC, D-lactate, and α-GST of the patients with strangulated intestinal obstruction were the highest among all the patients (Plt;0.01), and the expression levels of these three indices in the patients with simple intestinal obstruction were higher than those of the patients with acute simple appendicitis (Plt;0.05). The AUC of HDC (0.913) was larger than that of D-lactate (0.872) and α-GST (0.836) (P=0.000, P=0.000, respectively). When the cut off value of HDC was 31.00 μg/L, the sensitivity, specificity, false negative rate, and false positive rate of HDC were 74.5%, 94.6%, 25.5%, and 5.4%, respectively, which were all better than those of D-lactate and αGST. The occurrence rates of SIRS and abdominal cavity infection of the patients with strangulated intestinal obstruction were significantly higher than those of patients with simple intestinal obstruction (P=0.046) and acute simple appendicitis (P=0.027); while there was not significantly different of pulmonary infection among all the patients (P=0.728). The expression level of serum HDC in patients with strangulated intestinal obstruction suffered from SIRS (P=0.000) or abdominal cavity infection (P=0.002) was significantly higher than that of not-suffered from SIRS or uninfected patients. Meanwhile, the expression levels of serum D-lactate and α-GST in the patients with strangulated intestinal obstruction suffered from SIRS were higher than those of notsuffered from SIRS patients (P=0.032, P=0.021, respectively). The expression levels of HDC, D-lactate, and α-GST were significantly correlated with SIRS and abdominal cavity infection (Plt;0.05), among which the level of HDC and the incidence of SIRS had the highest correlation (r=0.608, P=0.001). ConclusionHDC may be a more effective index for diagnosing intestinal mucosal injury of patients with intestinal obstruction.