Cytomegalovirus Colitis Presenting as a Cecal Pseudotumor Mimicking Colorectal Malignancy in a Patient With Advanced HIV: A Case Report.

Cytomegalovirus (CMV) is an opportunistic pathogen that frequently involves the gastrointestinal tract in immunocompromised patients, particularly those with advanced HIV infection. CMV colitis typically presents with nonspecific gastrointestinal symptoms and endoscopic ulcerations. Mass-forming lesions, however, are an exceptionally rare manifestation and may mimic malignancy.  We report a case of a 64-year-old man with untreated HIV/AIDS (CD4+ T-cell count 24 cells/μL, HIV RNA 2,748,289 copies/mL) who was brought to the emergency department by ambulance after a fall, along with progressive encephalopathy, and was found to have a cecal mass on imaging despite the absence of gastrointestinal complaints. Colonoscopy demonstrated multiple friable, fungating, malignant-appearing masses and a mass causing mild obstruction at the junction between the ascending colon and the cecum. Despite initial concern for colorectal adenocarcinoma, histopathology revealed CMV inclusions without evidence of malignancy. The patient underwent a right hemicolectomy prior to definitive diagnosis and was treated with ganciclovir followed by valganciclovir. This case highlights the importance of considering CMV in the differential diagnosis of gastrointestinal mass lesions in severely immunocompromised patients in order to potentially avoid unnecessary surgical intervention.