A 58-year-old woman presents with nephrotic syndrome (proteinuria 8 g/day, serum albumin 2.1 g/dL) and normal complement levels. Vital signs: BP 148/92, HR 88, RR 16, Temp 37°C, SpO2 98%. She denies recent infections and takes no immunosuppressants. Kidney biopsy shows glomerular deposits. The pathologist suspects amyloidosis. Which stain would demonstrate apple-green birefringence under polarized light microscopy if amyloidosis is confirmed?

  1. A)Mucicarmine
  2. B)Congo redGABARITO
  3. C)Prussian blue
  4. D)Periodic acid Schiff
  5. E)Masson trichrome

Explicação

Congo red binds beta pleated sheet structure in amyloid and produces apple green birefringence under polarized light. This is a classic pathologic test for confirming amyloid deposition. Ver explicação completa e trilha adaptativa →

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