CASE 52 (June 2010)
A 56-year-old man presented with edema, which had developed over the previous months. Laboratory evaluation revealed proteinuria 3.8 g/24h, hypoalbuminemia (2.4 g/dL). No hematuria. Serum creatinine level of 1.2 mg/dL.
A renal biopsy was done, and a diagnosis of membranous nephropathy was made on the basis of the histology findings. This biopsy was studied without immunofluorescence.
We received, to interconsultation, the histological slides (H&E, Masson's trichrome, methenamine-silver and PAS) and the block of paraffin-embedded tissue.
See the images. What is your presumptive diagnosis? Would you suggest other stainings?
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. Methenamine-silver stain, X400.
Figure 4. Methenamine-silver stain, X400.
Figure 5. Methenamine-silver stain, X400.
Figure 6.Masson's trichrome stain, X200.
Figure 7. Masson's trichrome stain, X400.
Do you have a presumptive diagnosis?
What other techniques would you suggest on new sections of the paraffin-embedded tissue?