The demonstration of chromaffin granules is used for the diagnosis of which condition?

• A. Pheochromocytoma
• B. Alzheimer disease
• C. Renal disease
• D. Hepatic disease

Answer: (A)

Chromaffin granules are the catecholamine-containing secretory vesicles found in adrenal medulla chromaffin cells. They can be demonstrated histochemically by the chromaffin reaction, where catecholamines are oxidized in the presence of chromium salts and the granules stain brown to black. This positive chromaffin reaction is a hallmark of cells derived from chromaffin tissue, which is why tumors like pheochromocytoma—arising from these chromaffin cells—show prominent chromaffin granules. The presence of these granules helps confirm pheochromocytoma because the other listed conditions—Alzheimer disease, renal disease, and hepatic disease—do not involve chromaffin tissue or rely on this specific histochemical demonstration.