CASE 80 (October 2012)
The patient is a 57-year-old man with back pain and paresthesias in the lower limbs. Multiple pathological vertebral fractures were evidenced. On electrophoresis was found a small gamma peak.
Other laboratory tests: serum creatinine: 1.4 mg/dL, BUN 30 mg/dL, creatinine clearance 57 mL/m2/h. Proteins in urine 24 hours: 2.3 g. There are also glucosuria, hypophosphatemia and mild hypokalemia (probably Fanconi).
A renal biopsy was undertaken. See the images.
Figure 1. H&E, X200.
Figure 2. H&E, X400.
Figure 3. H&E, X400.
Figure 4. H&E, X400.
Figure 5. Masson's trichrome stain, X400.
Figure 6. Methenamine-silver stain, X100.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Masson's trichrome stain, X400.
Figure 9. Masson's trichrome stain, X400.
Figure 10. PAS, X400.
Figure 11.Masson's trichrome stain, X400.
Figure 12. Immunofluorscence for kappa light chain, X200.
Figure 13. Immunofluorscence for kappa light chain, X400.
Figure 14. Immunofluorscence for lambda light chain, X400.
Direct immunofluorescence for IgA, IgG, IgM, C3 and C1q: Negative.
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