CASE 169 (March 2020)
The patient is a 14-year-old boy with insulin-requiring diabetes mellitus, diagnosed 3 years earlier. The control of his disease has been somewhat irregular, with HbA1c levels above 6.5%. Mild proteinuria is detected: between 350 and 600 mg/day (approximately 10 mg/m2/h) in the measurements of the last 6 months. Serum creatinine: 0.5 mg/dL, BUN: 11 mg/dL. There is no hematuria; urinary sediment: normal. Studies of autoimmunity and infections: negative. Serum complement: normal.
Due to the short time since the diagnosis of diabetes, it is decided to take renal biopsy. See the images.
Figure 1. PAS, X200.
Figure 2. Methenamine-silver stain, X100.
Figure 3. Masson's trichrome stain, X400. Normal.
Figure 4. PAS, X400. Glomerulus with normal appearance.
Figure 5. Methenamine-silver stain, X400. Capillary walls and mesangium without evident alterations.
Figure 6. EM. original magnification, X3,500.
Figure 7. EM. original magnification, X3,500.
Direct immunofluorescence for IgA, IgG, IgM, C3, and C1q: Negative.
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