A 38-years-old woman, housewife, with hypothyroidism treated from two years ago, and high blood pressure from eigth months ago, treated without drugs, presented with one month of general weakness, and facial and legs edema. There are not cardiorespiratory, neurologic, neither cutaneus symptoms.
On physical examination, she appeared well, with facial and legs edema. The blood pressure was 150/100 mm Hg, the pulse 72 beats per minute, ritmic, respiratory frequence: 20 per minute. She did not have fever. Pulmonary sounds were disminished in both basal areas.
Laboratory tests: Hb: 10.5 mg/dL, Hto. 32%; white cells: 4,900 per mm3, neutrophils: 73%; lymph.: 21%; Eosinoph.: 4%; platelets: 227,000 per mm3, creatinine 1,9 mg/dL, BUN 35 mg/dL. Glycemia: 85 mg%; total cholesterol: 185 mg/dL; calcium: 9,5 meq/L.
Urinalysis: pH: 5.0; density: 1,015; proteins: >300 mg/dL, 3,1 g/24h.; urinary volume:1,600 cc; erythrocytes: 250 HPF.
Renal sonography show size increase with normal cortico-medullary differentiation. Pulmonary radiography show bilateral effacement of costophrenic angle due to liquid.
Immunological test: ANAs, ANCAs, anti-DNA, HIV, and serum complement levels were ordered but the results are not arrived at biopsy procedure moment. Tests for hepatitis virus were negative.
A renal biopsy was undertaken.
What is your clinical diagnosis?
See the images.
Figure 1. H&E, x400.
Figure 2. H&E, x400.
Figure 3. H&E, x400.
Figure 4. H&E, x400.
Figure 5. H&E, x400.
Figure 6. Immunofluorescence using antiserum to IgG (left) and IgA (right), X400.
Figure 7. Immunofluorescence using antiserum to C3 (left) and C1q (right), X400.
Immunofluorescence for IgM was positive too and the image was similar to IF for C3.
What is your diagnosis? ¿Are there any particular microscopic feature?