CASE 64 (June 2011)
An otherwise healthy 42-year-old woman presented with a 1-month history of edemas and general malaise; no other symptoms.
On physical examination, the patient appears well; blood pressure of 135/85 mm Hg, pulse rate of 71 bpm, no fever. Edema in both lower limbs. Bilateral legs edema, without ascites. No abnormalities of the skin or mucosal.
Laboratory: complete blood cell count and coagulation studies were normal. Serum creatinine: 1.8 mg/dL, BUN: 29 mg/dL. Parathormone: normal range. Urinalysis: density: 1,018, proteins: 500 mg/dL, 12-15 erythrocytes/HPF, leukocytes: 2-3/HPF, no casts. Proteinuria: 6.8 g/24h. Studies for hepatitis viruses: negative. HIV: negative; ANA: 1:80 speckled; anti-DNA: negative; C3: 68 mg/dL (90-180); C4: 12 mg/dL (10-40); cryoglobulins: negative; ANCA: negative. Creatinine clearance: 44.2 ml/min. Serum albumin: 2.5 g/dL. Total cholesterol: 234 mg/dL; LDL: 145 mg/dL; triglycerides: 149 mg/dL. Renal ultrasound: mild increase in size and echogenicity, with preserved cortico-medullary differentiation.
What is your clinical diagnosis?
A renal biopsy was done. See the images.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. Masson's trichrome stain, X400.
Figure 4. Methenamine-silver stain, X400.
Figure 5. Methenamine-silver stain, X400.
Figure 6. PAS, X400.
Figure 7. Direct immunofluorescence using antiserum to IgG, X100.
Figure 8. Direct immunofluorescence using antiserum to IgG, X400.
Figure 9. Direct immunofluorescence using antiserum to C3, X400.
Immunofluorescence staining for IgA, IgM, C1q, kappa and lambda: Negative.
What is your diagnosis?