OBJECTIVE To explore the distribution of pathogens isolated from the cardiac surgery children with postoperative catheter-related bloodstream infection (CRBSI) and observe the transforming growth factor β1(TGF-β1) gene polymorphisms and the change of high-sensitivity C-reactive protein (hs-CRP), Smad homologue 2 and Smad 3 levels.

METHODS A total of 88 children who received peripherally inserted central catheter (PICC) puncture after cardiac surgery and were complicated with postoperative CRBSI in the First People′s Hospital of Zunyi from Aug. 2019 to Oct. 2023 were assigned as the infection group. Meanwhile, 110 children who were treated with PICC and did not have postoperative CRBSI were randomly chosen as the non-infection group. The baseline data, TGF-β1 gene polymorphisms and the levels of hs-CRP, Smad 2 and Smad 3 were compared between the two groups. The distribution of the pathogens isolated from the infection group was observed. The values of hs-CRP, Smad 2 and Smad 3 in diagnosis of the postoperative CRBSI in the cardiac surgery children were analyzed by receiver operating characteristic (ROC) curves.

RESULTS The proportions of patients with intravenous catheter indwelling no less than 10 days, length of intensive care unit (ICU) stay no less than 5 days, the frequencies of CC genotypes and C allele at TGF-β1+869C/T locus were higher in the infection group than those in the non-infection group (P < 0.05). Acinetobacter baumannii was the predominant species of pathogen isolated from the infection group, accounting for 24.20%. The levels of serum hs-CRP, Smad 2 and Smad 3 of the infection group were (24.65±7.65)mg/L, (13.54±2.45)pg/ml and (13.65±2.65)pg/ml, respectively, higher than those of the non-infection group (all P < 0.001). The area under the curve (AUC) of the joint detection of hs-CRP, Smad 2 and Smad 3 was highest in diagnosis of the postoperative CRBSI in the cardiac surgery children (P < 0.05).

CONCLUSIONS A. baumannii is dominant among the pathogens isolated from the cardiac surgery children with postoperative CRBSI. The postoperative CRBSI may be associated with the intravenous catheter indwelling time and length of ICU stay. The C allele at TGF-β1+869C/T locus may be the susceptibility gene for the postoperative CRBSI. The joint detection of hs-CRP, Smad 2 and Smad 3 has the highest value in diagnosis of the postoperative CRBSI.