Prophylactic negative-pressure wound therapy after ileostomy reversal for the prevention of wound healing complications in colorectal cancer patients: a randomized controlled trial.

BACKGROUND: The aim of this study was to assess the usefulness of protective negative-pressure wound therapy (NPWT) in the reduction of wound healing complications (WHC) and surgical site infections (SSI) after diverting ileostomy closure in patients who underwent surgery for colorectal cancer. METHODS: In this prospective randomized clinical trial in a tertiary academic surgical center, patients who had colorectal cancer surgery with protective loop ileostomy and were scheduled to undergo ileostomy closure with primary wound closure from January 2016 to December 2018 were randomized to be treated with or without NPWT. The primary endpoint was the incidence of WHC. Secondary endpoints were incidence of SSI, length of postoperative hospital stay (LOS), and length of complete wound healing (CWH) time. RESULTS: We enrolled 35 patients NPWT (24 males [68.6%]; mean age 61.6 ± 11.3 years), with NPWT and 36 patients (20 males [55.6%]; mean age 62.4 ± 11.3 years) with only primary wound closure (control group). WHC was observed in 11 patients (30.6%) in the control group and 3 (8.57%) in the NPWT group (p = 0.020). Patients in the NPWT group had a significantly lower incidence of SSI (2 [5.71%] vs. 8 [22.2%] in the control group; p = 0.046) as well as significantly shorter median CWH (7 [7-7] days vs. 7 [7-15.5] days, p = 0.030). There was no difference in median LOS between groups (3 [2.5-5] days in the control group vs. 4 [2-4] days in the NPWT group; p = 0.072). CONCLUSIONS: Prophylactic postoperative NPWT after diverting ileostomy closure in colorectal cancer patients reduces the incidence of WRC and SSI. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov (NCT04088162).

New structures of the O-specific polysaccharides of Proteus. 2. Polysaccharides containing O-acetyl groups.

Structures of five new O-specific polysaccharides of Proteus bacteria were established. Four of them, Proteus penneri 4 (O72), Proteus vulgaris 63/57 (O37), Proteus mirabilis TG 277 (O69), and Proteus penneri 20 (O17), contain O-acetyl groups in non-stoichiometric quantities, and the polysaccharide of P. penneri 1 is structurally related to that of P. penneri 4. The structures were elucidated using NMR spectroscopy, including one-dimensional 1H- and 13C-NMR spectroscopy, two-dimensional 1H,1H correlation (COSY, TOCSY), H-detected 1H,13C heteronuclear multiple-quantum coherence (HMQC), heteronuclear multiple-bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY or ROESY), along with chemical methods. The structural data obtained are useful as the chemical basis for the creation of the classification scheme for Proteus strains.

Structure of the O-specific polysaccharide of Proteus mirabilis D52 and typing of this strain to Proteus serogroup O33.

The acidic O-specific polysaccharide chain (O-antigen) of the lipopolysaccharide (LPS) of Proteus mirabilis strain D52 was studied using chemical analyses along with 1H-NMR and 13C-NMR spectroscopy, including 2D COSY, TOCSY, ROESY, H-detected 1H,13C and 1H,31P HMQC experiments. The polysaccharide was found to contain D-ribitol 5-phosphate (D-Rib-ol-5-P) and ethanolamine phosphate (Etn-P) and has the following structure: D-Rib-ol-5-P (3) approximately 75% EtnP(6)-->2)-beta-D-Galp-(1-->3)-alpha-D-GlcpNAc-(1-->3)-beta-D-Glcp-(1-->3)-beta-D-GlcpNAc-(1-->). This structure is identical with that of the O-polysaccharide of P. mirabilis O33 strain 59/57, and, hence, P. mirabilis D52 belongs to the same Proteus serogroup O33. Serological studies with O-antiserum against P. mirabilis D52 confirmed this but showed that the LPS species of P. mirabilis 59/57 and D52 are not identical, having different epitopes in the core region. A serological cross-reactivity of P. mirabilis D52 O-antiserum was observed with LPS of two other Proteus strains, P. mirabilis O16 and P. penneri 103, which have structurally different O-polysaccharides. The role of charged groups, Rib-ol-5-P and Etn-P in the immunospecificity is discussed.