CASE 25 (March 2008)
The patient is a 52-year-old woman with a history of rheumatoid arthritis that was diagnosed 10 years ago: clinical and radiological criteria, and rheumatoid factor >160 IU/mL.
From two years ago she presents persistent microscopic hematuria (6-50 erythrocytes/HPF) without proteinuria or renal dysfunction. No casts in the urinalysis, but there is deformed erythrocytes.
Treatment: methotrexate, prednisone and NSAIDs from several years ago. Chloroquine from 8 months ago. She does not have received gold compounds. She received one dose of rituximab three months before the renal biopsy.
The patient does not present gastrointestinal, cardiorespiratory or gynecological symptoms. She presented papillary thyroid carcinoma 18 years ago, surgically treated, without relapse.
Other tests: ANAs: 1:180 homogeneous pattern, ENAs negative, native anti-DNA negative.
She does not have blood hypertension, edema or skin lesions. Deformities in joints due to their underlying disease.
The urological and gynecological examination and the renal ultrasonography were normal. It was concluded that hematuria is glomerular.
With the diagnosis of persistent isolated microscopic hematuria (without proteinuria or renal dysfunction) a renal biopsy was undertaken.
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See the images.
Figure 1. Mild mesangial cell proliferation: >3 nuclei/mesangial area (H&E, X400).
Figure 2. Some glomeruli appear almost normal (H&E, X400).
Figure 3. PAS stain, X400.
Figure 4. Methenamine-silver stain, X400.
Figure 5. Cellularity in mesangial areas near to glomerular hilium is not adequate to evaluate mesangial hipercellularity (Methenamine-silver stain, X400).
Direct immunofluorescence for IgA, IgG, IgM, C3, C1q, and kappa and lambda light chains: Negative (12 glomeruli).
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