Gut microbiota influence anastomotic healing in colorectal cancer surgery through modulation of mucosal proinflammatory cytokines.

OBJECTIVE: Colorectal cancer (CRC) is the third most diagnosed cancer, and requires surgical resection and reconnection, or anastomosis, of the remaining bowel to re-establish intestinal continuity. Anastomotic leak (AL) is a major complication that increases mortality and cancer recurrence. Our objective is to assess the causal role of gut microbiota in anastomotic healing. DESIGN: The causal role of gut microbiota was assessed in a murine AL model receiving faecal microbiota transplantation (FMT) from patients with CRC collected before surgery and who later developed or not, AL. Anastomotic healing and gut barrier integrity were assessed after surgery. Bacterial candidates implicated in anastomotic healing were identified using 16S rRNA gene sequencing and were isolated from faecal samples to be tested both in vitro and in vivo. RESULTS: Mice receiving FMT from patients that developed AL displayed poor anastomotic healing. Profiling of gut microbiota of patients and mice after FMT revealed correlations between healing parameters and the relative abundance of Alistipes onderdonkii and Parabacteroides goldsteinii. Oral supplementation with A. onderdonkii resulted in a higher rate of leaks in mice, while gavage with P. goldsteinii improved healing by exerting an anti-inflammatory effect. Patients with AL and mice receiving FMT from AL patients presented upregulation of mucosal MIP-1α, MIP-2, MCP-1 and IL-17A/F before surgery. Retrospective analysis revealed that patients with AL present higher circulating neutrophil and monocyte counts before surgery. CONCLUSION: Gut microbiota plays an important role in surgical colonic healing in patients with CRC. The impact of these findings may extend to a vast array of invasive gastrointestinal procedures.

Acute right-sided ischemic colitis in a COVID-19 patient: a case report and review of the literature.

INTRODUCTION: In addition to attacking the respiratory system, the coronavirus disease may attack the gastrointestinal tract in various ways, one of which is by creating a coagulopathy that may lead to acute ischemia of the bowel, increasing morbidity and mortality rates in these patients. PRESENTATION OF CASE: We present a case of a white 72-year-old European male, who was admitted to the intensive care unit after developing COVID-19-induced acute respiratory distress syndrome. On the third week, despite a favorable evolution of his respiratory symptoms, the patient became clinically septic; laboratory findings showed an augmentation of his D-dimer, fibrinogen, C-reactive protein, and procalcitonin levels. Imaging showed signs of ischemia of the right colon. The patient was taken to the operating room; only the right side of his colon was ischemic, with a well demarcated cut-off. A laparoscopic right hemicolectomy with a terminal ileostomy was performed. The patient was able to go home 2 weeks after surgery. DISCUSSION AND CONCLUSION: Ischemic colitis is an uncommon pathology in the general population, and is rare in COVID-19 patients. Most cases of ischemic colitis in COVID-19 patients in the literature were limited to the left colon, with < 10 cases involving the right colon. Accurate and quick diagnosis with appropriate management is the key to avoid any mortality in those patients who are already weakened by the coronavirus.

Sclerosing encapsulating peritonitis presenting as acute-on-chronic small-bowel obstruction in a patient with history of peritoneal carcinomatosis.

Sclerosing encapsulating peritonitis (SEP) is a whitish fibrous envelope that encapsulates intra-abdominal peritonealized organs. Although it pathophysiology is not well understood, several possible causes have been reported in the literature, including peritoneal dialysis, past abdominal surgeries, peritonitis, beta-blockers and peritoneal carcinomatosis (PC). Some idiopathic cases, with no apparent causes, were described. We present a SEP case in a 43-year-old woman with a surgical history of pancreatic and liver resection for metastatic pseudopapillary pancreatic tumor, followed by several peritonectomies for PC. She was admitted for acute-on-chronic small-bowel obstruction that did not resolve with conservative management. Surgical exploration revealed a fibrous sheath covering the small-bowel. Extensive dissection, along with small-bowel segmental resection and anastomosis, was performed. The specimen was cancer-free. The mechanism through which SEP develops in certain surgical patients is still unknown. This report presents a case of successful surgical management and a review of the literature.