Cytomegalovirus colitis in intensive care unit patients: Difficulties in clinical diagnosis

Purpose: Cytomegalovirus (CMV) infection occurs increasingly in critically ill patients in intensive care units (ICUs). We reported CMV colitis which has rarely been recognized in the ICU patients. Methods: CMV DNA was detected by polymerase chain reaction (PCR) for blood and/or stool samples. Definite diagnosis of CMV colitis required histopathology or CMV immunohistochemical staining of colorectal biopsies. We reviewed ICU patients characterized by positive blood or stool CMV-PCR with colorectal bleeding or water diarrhea. Results: We identified 18 patients (biopsy-proved, n = 8; probable cases, n = 10). The most common comorbidities were chronic renal disease, diabetes mellitus, and coronary artery disease. Stool CMV-PCR was positive in 7 of 10 patients (2 of 3 biopsy-proved and 5 of 7 probable cases). Colonoscopy was performed for 15 patients, revealing ulcerative or polypoid lesions. The endoscopists obtained colonic biopsies from 9 patients. Yet, the pathologists reported CMV colitis for 4 patients. Additional 4 patients were confirmed using immunohistochemical stain by the request of clinical physicians. Pseudomembranous colitis was found in 4 patients. Conclusion: Diagnosis of CMV colitis seems difficult in clinical practice and need persistent communication between clinicians. The positive stool CMV-PCR result was a useful hint for adding immunohistochemical stain in mucosal biopsies to make a definite diagnosis of CMV colitis.