CASE 206 (April 2023)

Clinical information

The patient is a 56-year-old woman who is evaluated for presenting edema of several weeks' evolution. In the paraclinical studies nephrotic proteinuria was documented: 3.6 g/24h, creatinine 1.2 mg/dL; BUN 16 mg/dL. Negative studies for viruses and autoimmunity. Normal serum complement. Serum albumin: 3.1 g/dL. In the urinary sediment: 8-10 erythrocytes/hpf, leukocytes 3/hpf, no casts were reported.

Renal biopsy is done, look at the images.

Figure 1. H&E, X100.

Figure 2. H&E, X400.

Figure 3. PAS, X400.

Figure 4. Masson´s trichrome stain, X400.

Figure 5. Metenamina-silver stain, X400.

Figure 6. Metenamina-silver stain, X400.

Figure 7. Immunofluorescence for IgG, X400.

Figure 8. Immunofluorescence for light chains kappa, X400.

Figure 9. mmunofluorescence for light chains lambda, X400.

Figure 10. Immunohistochemistry for CD68 (monocytes / macrophages), X400. In addition to positive cells in glomeruli, there are interstitial cells with similar characteristics.

Figure 11. Electron microscopy, original magnification, X1.500.

Figure 12. Electron microscopy, original magnification, X2.100.

Figure 13. Electron microscopy, original magnification, X1.500.

Figure 14. Electron microscopy, original magnification, X4.000. The granules or crystals are in the cytoplasm of intracapillary cells.

Direct immunofluorescence for IgA, IgM, C3 and C1q: Negative.

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