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What is A pathologist examines a renal biopsy from a 45 year old man with nephrotic syndrome and requested a congo red stain to confirm the nature of an amorphous acidophillic extracellular hyalin substances localized within the mesengial matrix of the glomeruli A positive test confirms the presence of and explain in detail?
The answer is B. A positive congo red test confirms the presence of amyloid. Apple green birefringence is abserved under polarized light.