A two year-old girld presented with complete nephrotic syndrome from 4 months ago. Proteinuria: 120 mg/m2/h, edema, hyperlipidemia and hypoalbuminemia. She does not have familial history of renal diseases.
Immunologic tests did not demonstrate alterations. In the urinalysis: erythrocytes: 3-4 HPF, proteins: >300 mg/dL. Seric creatinine: 0.6 mg/dL; creatinine clearance: 98 mL/min.
Treatment with steroids was started, 60 mg/m2/d, without response after two months of continue treatment.
With corticoresistant nephrotic syndrome diagnosis a renal biopsy was undertaken.
See the images.
Figure 1. H&E, X100.
Figure 2. H&E, X300.
Figure 3. H&E, X400.
Figure 4. Gomori`s trichrome, X400.
Figure 5. Metenamine-silver, X400.
Figure 6. Immunofluorescence using antiserum to C1q, X400. All the 11 glomeruli identified in the renal tissue for this technique show similar features.
Immunofluorescence for IgA, IgG, IgM, and C3 were negative.
What is your diagnosis?