The patient is a 37 year old Hispanic woman. She presented in October 2006 with purulent rhinorrhea, fever: 39 ºC from two weeks ago; she noticed low urinary volume and pigmented urine, and increasing ankle oedema over the previous 3 days. On examination BP 160/100 mmHg; heart rate: 90. Skin, chest, abdomen, and nervous system exam showed no abnormalities. There was marked pedal and pre-tibial oedema. There is purulent and sanguineous material in the nasal cavities.
Urinalysis showed proteins 300 mg/dL, eritrocites: >60 HPF, and red blood cell casts. Serum creatinine was 13.5 mg/dL; BUN: 89; ANAs negative, anti-DNA negative, HBSAg, HCV, HIV, ANCA, and cryoglobulins all negative. C3: 33 (80-160); C4 23 (17-40).
Renal sonography showed increase in the renal size with normal cortex/medulla ratio.
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A renal biopsy was performed.
See the images.
Figure 1. Masson's trichrome stain, x200.
Figure 2. Methenamine silver stain, x200.
Figure 3. H&E, x400.
Figure 4. Masson's trichrome stain, x400.
Figure 5. Methenamine silver stain, x400.
Figure 6. Methenamine silver stain, x400.
Figure 7. Immunofluorescence using antiserum to IgG, x400. Staining was diffuse.
Figure 7. Immunofluorescence using antiserum to C3, x400. Staining was diffuse.
Immunofluorescence for IgA, IgM, and C1q were negative.
Epithelial crescents in 9 of 12 glomeruli.
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