Systemic Oxalosis Mimicking Transthyretin Amyloid Cardiomyopathy

Figures

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  Figure 1. Cardiac Imaging and Biopsy Findings From Our Patient with False Positive Scintigraphy Because of Systemic Oxalosis (A) Transthoracic echocardiography in parasternal short-axis views with concentric left ventricular hypertrophy (interventricular septal diastolic thickness: 1.47 cm) and biatrial enlargement (left) and in apical 4 chamber (right) view; (B) technetium-99m pyrophosphate scintigraphy scintigraphy with diffuse grade 3 myocardial uptake on planar imaging (left) and single-photon emission computed tomography fusion image in axial plane shows circumferential uptake in the left ventricle, most pronounced in the lateral wall (right); (C) endomyocardial biopsy with hematoxylin and eosin stain under depolarized light without evidence of amyloid deposition; and (D) retrospective re-evaluation of the endomyocardial biopsy obtained pre mortem, with hematoxylin and eosin stain under polarized light, now revealing deposition of crystals (performed post mortem following autopsy findings).

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  Figure 2. Autopsy Images Demonstrating Myocardial and Renal Oxalate Deposition in the Setting of Systemic Oxalosis (A) Myocardium pathology demonstrating numerous colorless, birefringent, rosette-shaped calcium oxalate crystals. There is no inflammatory reaction. (B) Kidney pathology demonstrates large chunks of calcium oxalate deposits, which also shows findings of chronic kidney disease, including glomerulosclerosis, tubular atrophy, and interstitial fibrosis.