Figures 16, 17. (16) CT scan obtained in a 67-year-old man who developed PMC 1 week after undergoing surgery for spine infection shows thickening of the colon wall and haustral folds limited to the rectosigmoid colon. (17) CT scan obtained in a 78-year-old woman who developed PMC following antibiotic therapy shows nodular wall thickening limited to the rectosigmoid colon (arrows).