CASE 91 (September 2013)
The patient is a 81-year-old man with a history of diabetes mellitus and arterial hypertension of many years of evolution, apparently well controlled. He is evaluated by presenting lower limb edema for about a month. No other symptoms. Medications: ACE inhibitors and glibenclamide.
A renal biopsy was performed. See the images.
Figure 1. H&E, X400.
Figure 2. H&E, X400.
Figure 3. Masson's trichrome stain, X400.
Figure 4. PAS, X400.
Figure 5. Methenamine-silver stain, X400.
Figure 6. Methenamine-silver stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Direct immunfluorescence for IgG, X400.
Figure 9. Direct immunfluorescence for C3, X400.
Figure 10. Direct immunfluorescence for kappa light chains, X400.
Figure 11.Direct immunfluorescence for lambda light chains, X400.
Figure 12. Direct immunfluorescence for IgG subclasses: upper left: IgG1, upper right: IgG2, lower left: IgG3 (the only positive); lower right: IgG4. Original magnification: X400.
Immunofluorescence for IgA, IgM and C1q: Negative.
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