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The biopsy is from a 61-year-old man with a history of intermittent microscopic hematuria for many years who presents with recent 18-pound weight loss and nephrotic syndrome.  His creatinine is mildly elevated at 1.3 mg/dL.  He has 12.5 g of proteinuria and his serum albumin is 2.6 mg/dL.  The biopsy shows diffuse mild mesangial matrix expansion with no necrosis or proliferative lesions (Fig. 1).  Immunofluorescence microscopy shows extensive granular mesangial IgA deposits (3+) (Fig. 2), compatible with IgA nephropathy.  Interestingly, the Jones methenamine silver stain also shows argyrophilic spikes involving capillary loops, which are most suggestive of spicular amyloid deposits...

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