Fig. 12

POCUS study (a) using a high-frequency linear probe in multi-trauma patients who developed diarrhoea 2 weeks after starting antibiotic administration. The colonic wall is thickened with three distinct layers, mucosa (white arrow), submucosa (curved yellow arrow), and muscularis propria (interrupted arrow). Hyperechoic lines are seen covering the mucosa (arrowheads). These can be either pseudomembranes or air bubbles. These findings give the classical accordion sign of pseudomembranous colitis. Abdominal CT scan with intravenous contrast (b) which was performed at the same time shows the same accordion sign (white arrow). CT scan has the advantage of showing the hyperaemic mucosa with air bubble in the colonic wall (arrowhead)