CASE 88 (June 2013)
The patient is a 67-year-old man with lower limbs edema for about a month. Complete nephrotic syndrome was documented. Serum creatinine 1.2 mg/dL, BUN 27 mg/dL, Hb: 10 mg/dL, hematocrit 29%, platelets and white blood cell count were normal. Studies for autoimmunity and viruses were negative.
See the images of the renal biopsy.
Figure 1. H&E, X400.
Figure 2. H&E, X400.
Figure 3. Masson's trichrome stain, X400.
Figure 4. Masson's trichrome stain, X400.
Figure 5. PAS, X400.
Figure 6. Methenamine-silver stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Immunostaining for kappa light chains, X400.
Figure 9. Immunostaining for lambda light chains, X400.
Figure 10. Immunostaining for A amyloid, X400.
Figure 11. Congo red with polarized light in diverse grades of lens rotation, X400.
Immunofluorescence for IgA, IgG, IgM, C3, and C1q: Negative.
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