Factors Associated with Cytomegalovirus (CMV) Procto-Colitis in Immunocompetent Adults: A Systematic Review

Objective: The pathophysiology of CMV procto-colitis in immunocompetent adults is poorly understood. We aimed to systematically review the literature to explore factors, presenting symptoms and endoscopy findings associated with CMV procto-colitis in immunocompetent adults. Methods: Following PRISMA guidelines, we conducted a narrative systematic review by searching MEDLINE, EMBASE, EMCARE and CINAHL for manuscripts published up to August 2023. One author screened manuscript abstracts; two authors independently conducted a full text review. We included manuscripts which included primary data of immunocompetent adults with CMV procto-colitis except case reports. Quality and risk of bias was assessed independently by two authors using the Joanna Briggs institute critical appraisal tools. Results: 8 manuscripts were included in the final review from the USA (n=2), China (n=2), Korea (n=2), India (n=1) and Brazil (n=1) and consisted of 6 case series, one casecontrol study and one cross-sectional study published between 1988-2022. We identified demographic and behavioural factors (older age, lower BMI, receptive anal sex), infection factors (urinary tract infections, shigellosis, Hepatitis C, COVID-19, sepsis, antimicrobial use), medical conditions (cardiovascular disease, respiratory disease, renal disease, autoimmune disease, diabetes) and hospitalisation factors (intensive care admission, longer length of hospital stay) associated with CMV procto-colitis in immunocompetent adults. Patients presented with rectal bleeding, diarrhoea, melaena, fever, nausea/vomiting, abdominal pain/bloating and constipation. Large bowel endoscopy findings were ulcers, erosions, and erythema and polyp/mass lesions. Conclusion: We have highlighted factors, presenting symptoms and endoscopy findings associated with CMV procto-colitis in immunocompetent patients which provides insight for clinical guideline development and future research.