This patient has a family history of hematuria. The urine shows dysmorphic red cells and labs are notable for a BUN of 38 mg/dL and a serum creatinine of 2.1 mg/dL. The pic shows an electron micrograph of the patient's renal biopsy. What does the picture show and what is the likely cause for the hematuria.
The answer to the quiz of 1/14/12 is: large vessel vasculitis. The rash is livedo reticularis. The renal biospy shows a small interlobular artery with massive fibrinoid necrosis of the wall
and complete occlusion of the lumen by fibrin, necrotic debris and inflammatory
cells. This lesion usually result
in infarction of the parenchyma; the sediment is often bland or reflects the
acute tubular necrosis. In this picture the upper portion of the arterial wall
is completely destroyed, with fibrinoid material
invading the parenchyma.
The organization of this lesion will result in the formation of a
aneurysm. Large vessel vasculitides are usually
ANCA-negative.
This is a renal biopsy of a 55 year old patient with a 1 month history of general achiness and the development over the past 6 months of hypertension. He has noted a blotchy rash on his lower extremities. He is on amlodipine 10 mg/day. Examination shows a white male in no distress, blood pressure 152/94 mmHg, afebrile. Otherwise negative exam except for some mild epigastric tenderness and a rash on his lower extremities (see pic). He On routine evaluation, his BUN was 42 and serum creatinine 1.8 mg/dL. Urinalysis is bland. ANA and ANCA are negative. Complements are normal. Antiphospholipid antibody assay is negative. Cryoglobulins are negative. A renal biopsy is performed (see pic below).
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Lower extremity rash
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Renal biopsy
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