Primary hyperoxaluria: report of a patient with livedo reticularis and digital infarcts.

Primary hyperoxaluria encompasses 3 rare genetic disorders of glyoxylate metabolism characterized by excessive urinary excretion of oxalic acid, resulting in oxalosis. Patients typically have recurrent calcium oxalate nephrolithiasis and nephrocalcinosis, leading to chronic renal failure and death from uremia. Oxalate can deposit in extrarenal sites such as the heart, walls of arteries and veins, bone, and skin. We report a patient who presented with acute renal failure and later experienced livedo reticularis and peripheral gangrene before the diagnosis of primary hyperoxaluria was established. A skin biopsy specimen demonstrated numerous characteristic elongate to diamond-shaped, radially oriented, pale yellow translucent oxalate crystals within the vessels, and vessel walls of the subcutaneous fat that were strongly birefringent under polarized light.