Alcian blue PAS hematoxylin is used for the detection of which condition?

• A. Intestinal metaplasia
• B. Basal cell carcinoma
• C. Crohn’s disease
• D. Colitis

Answer: (A)

The main idea this stain tests is the ability to detect intestinal-type mucin in tissue, which signals intestinal metaplasia. Alcian blue stains acidic mucins blue, while PAS stains neutral mucins magenta, and hematoxylin provides a blue nuclear counterstain. In intestinal metaplasia, gastric or esophageal mucosa adopts an intestinal-type epithelium with goblet cells that produce acidic mucins. Seeing blue-stained goblet cells (and the characteristic AB-PAS pattern) highlights these intestinal mucins, making the change easy to identify. This is particularly important in conditions like Barrett’s esophagus or gastric intestinal metaplasia, where the presence of goblet cells indicates a metaplastic transformation. The other conditions listed—basal cell carcinoma, Crohn’s disease, and colitis—do not rely on identifying intestinal-type mucins with this staining pattern, so Alcian blue PAS hematoxylin isn’t used to diagnose them.