CASE 61 (March 2011)
The patient is a 59-year-old man. He had a diagnosis of systemic hypertension for three years. He was referred to Nephrology because urinalysis showed proteinuria: 100 mg/dL. He had no diagnosis of diabetes mellitus, however one month ago his glycemia was 184 mg/dL, now it was 146 mg/dL. Glycosylated hemoglobin (HbA1c): 8.1% (3.8% - 6.4%). Serum creatinina 1.1 mg/dL, BUN: 15 mg/dL; his serum calcium was normal; proteinuria 1.6 g/24h. Creatinine clearance: 75 mg/m2/h. Urinalysis without erithrocytes, leukocytes or casts.
On physical examination: Good general condition, without edema; blood pressure: 135/85. No skin lesions. Ophthalmic Fundus examination was normal: no retinopathy.
Due to non-nephrotic proteinuria and a very recent diagnosis of diabetes mellitus, a renal biopsy was performed. View the images.
Figure 1. H&E, X100.
Figure 2. H&E, X100.
Figure 3. H&E, X400.
Figure 4. H&E, X400.
Figure 5. H&E, X400
Figure 6. H&E, X400.
Figure 7. Masson's trichrome stain, X400.
Figure 8. PAS stain, X400
Figure 9. Methenamine-silver stain, X400
Figure 10. Left: PAS; right: methenamine-silver; both X400
Figure 11. Direct immunofluorescence using antiserum to IgG, X400. "Pseudolineal".
Figure 12. Direct immunofluorescence using antiserum to IgM, X400. Focal and segmental immunostaining.
Figure 13. Direct immunofluorescence using antiserum to C3, X400. Focal and segmental immunostaining.
Immunofluorescence staining for IgA and C1q: Negative.
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