Congo Red Stain Tutorial: What does it show?
Positive Congo red staining in tissue with apple-green birefringence under polarized light is diagnostic of the presence of amyloid fibrils. Image A shows a glomerulus with Congo red positive mesangial staining while image B shows a renal biopsy with diabetic nephropathy that is negative for Congo red. Accurate interpretation of this stain hinges upon proper optimization so that there is elimination of nonspecific background staining.
Quick note: This post is to be used for informational purposes only and does not constitute medical or health advice. Each person should consult their own doctor with respect to matters referenced. Arkana Laboratories assumes no liability for actions taken in reliance upon the information contained herein.