CASE 160 (June 2019)
A 74-year-old man is evaluated for presenting nonspecific symptoms in the last month, he reports malaise, easy fatigue and edema. Personal history: systemic arterial hypertension diagnosed 15 years ago, with good control; prostatectomy 8 years ago due to hyperplasia. No known family history of kidney disease. At the physical examination: blood pressure: 160/100; normal mental sphere; edema of lower limbs, up to the knees. There are no skin lesions.
Paraclinical: Hb: 10.6 mg/dL, Ht: 31%, platelets: 290,000/mm2, normal leukogram. Serum Cratinin: 4.8 mg/dL, BUN: 87 mg/dL; C3 and C4 normal; ANA: negative. PR3-ANCA: positive: 10 IU/mL. Proteinuria: 1.8 g/24h. Urinary sediment with erythrocyte and leukocyte casts. Studies for viruses: negative. Cryoglobulins: negative. Protein electrophoresis: without monoclonal peak.
See the images of the renal biopsy.
Figure 1. Masson's trichrome stain, X200.
Figure 2. H&E, X400.
Figure 3. H&E, X400.
Figure 4. Masson's trichrome stain, X400.
Figure 5. Masson's trichrome stain, X400.
Figure 6. Masson's trichrome stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Methenamine-silver stain X400.
Figure 9. Masson's trichrome stain, X400.
Direct immunofluorescence for IgA, IgG, IgM, C3, C1q, kappa, and lambda: Negative.
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