TOPLINE:

Among patients with colonic diverticular disease, eosinophil and lymphocyte counts were increased in the submucosa at the diverticulum base of those undergoing emergency resection, and lymphocyte counts in adipose tissue were elevated in patients undergoing elective or emergency resections. 

METHODOLOGY:

• Previous studies reported mucosal eosinophilia in patients with colonic diverticular disease. Researchers explored whether the counts of eosinophils and other immune cells were increased in the submucosa and visceral adipose tissue of these patients.
• They analyzed resections from patients with colonic diverticular disease from an Australian pathology database between 2017 and 2019.
• Patients were classified based on surgical indication: elective or emergency. A separate control cohort comprised patients who underwent colonic resection for nondiverticular conditions.
• Among 82 colonic resections containing diverticula (patients’ median age, 71.5 years; 42 men), 37 were elective and 45 were emergency. The control cohort included 10 elective resections for colorectal cancer (patients’ median age, 68.5 years; 5 men).
• Stained slides of colonic resections were analyzed for eosinophil, neutrophil, and lymphocyte counts per five high-power fields in the submucosa and adipose tissue at the diverticulum base, neck, and ostia and at an adjacent normal region.

TAKEAWAY:

• At the submucosal base of diverticula, eosinophil counts were higher in emergency resections than in control resections (median, 12 vs 3.5; P = .01). Submucosal lymphocyte counts were markedly higher in emergency patients with nonperforated diverticulitis and perforated diverticulitis than in control patients (median, 310 and 317, respectively, vs 146; P ≤ .02).
• In the adipose tissue at the diverticulum base, lymphocyte counts were higher than in control resections in both elective (median, 56 vs 21; P = .02) and emergency resections (median, 66 vs 21; P = .007).
• Neutrophil and adipose eosinophil counts did not differ between colonic diverticular and control resections.

IN PRACTICE:

“This study suggests that, along with mucosal eosinophilia, increased submucosal eosinophils and adipose lymphocytosis may play a role in colonic diverticular disease pathophysiology,” the authors of the study wrote.

SOURCE:

This study, led by Raquel A. Cameron, University of Newcastle in Newcastle, Australia, was published online in the Journal of Gastroenterology and Hepatology.

LIMITATIONS:

Only 10 patients with nondiverticular conditions were included in the control cohort. Using colorectal cancer resections as nondiverticular controls was another limitation. Including twosymptomatic patients in the elective cohort may have influenced the findings.

DISCLOSURES:

This study was supported by Australia’s National Health and Medical Research Council. One author reported receiving support from Comvita Mānuka Honey, Brown University, and Microba. The same author reported holding patents or patent applications for several questionnaires and tools.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.