CASE 157 (March 2019)
A 21-year-old man is evaluated for having evening edemas in the lower limbs. In the physical examination, systemic hypertension is documented, without other alterations. Laboratory tests: mild anemia and elevated creatinine: 3.6 mg/dL, BUN: 75 mg/dL. In the urinalysis there is no hematuria or leukocyturia, proteinuria: 450 mg/24h. Studies of autoimmunity and infections: negative. On ultrasound, both kidneys are slightly enlarged, with punctate cysts and poor corticomedullary differentiation.
There is no pathological personal history. Family history: an uncle and a brother died with end-stage renal disease without clear cause; his mother died at 36 years of age due to a ruptured cerebral aneurysm and apparently had kidney disease, without knowing more about it.
See the images of the renal biopsy.
Figure 1. H&E, X100.
Figure 2. H&E, X100.
Figure 3. H&E, X200.
Figure 4. H&E, X400.
Figure 5. H&E, X200.
Figure 6. PAS, X400.
Figure 7. PAS, X100.
Figure 8. Masson's trichrome, X200.
Figure 9. Masson's trichrome, X100.
Figure 10. Methenamine-silver, X200.
All the glomeruli in the biopsy had severe dilation of Bowman's space, with retraction of the tuft (as seen in the previous images).
Direct immunofluorescence for IgA, IgG, IgM, C3, C1q, kappa, and lambda: Negative.
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