title: An unusual cause of acute kidney injury due to oxalate nephropathy in systemic scleroderma.
abstract: Oxalate nephropathy is an uncommon cause of acute kidney injury. Far rarer is its association with scleroderma, with only one other published case report in the literature. We report a case of a 75-year-old African-American female with a history of systemic scleroderma manifested by chronic pseudo-obstruction and small intestinal bacterial overgrowth (SIBO) treated with rifaximin, who presented with acute kidney injury with normal blood pressure. A renal biopsy demonstrated extensive acute tubular injury with numerous intratubular birefringent crystals, consistent with oxalate nephropathy. We hypothesize that her recent treatment with rifaximin for SIBO and decreased intestinal transit time in pseudo-obstruction may have significantly increased intestinal oxalate absorption, leading to acute kidney injury. Oxalate nephropathy should be considered in the differential diagnosis of acute kidney injury in scleroderma with normotension, and subsequent evaluation should be focused on bowel function to include alterations in gut flora due to antibiotic administration.
authors.forename: Heather M
authors.initials: HM
authors.lastname: Mascio
authors.forename: Christie A
authors.initials: CA
authors.lastname: Joya
authors.forename: Richard A
authors.initials: RA
authors.lastname: Plasse
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Baker
authors.forename: Michael F
authors.initials: MF
authors.lastname: Flessner
authors.forename: Robert
authors.initials: R
authors.lastname: Nee
mesh_terms: D058186:Acute Kidney Injury / Q000209:etiology* / Q000378:metabolism; D000368:Aged; D002129:Calcium Oxalate / Q000737:chemistry*; D005260:Female; D005769:Gastrointestinal Motility / Q000502:physiology; D005772:Gastrointestinal Transit / Q000502:physiology; D006801:Humans; D007408:Intestinal Absorption / Q000187:drug effects; D007410:Intestinal Diseases / Q000209:etiology; D007418:Intestinal Pseudo-Obstruction / Q000209:etiology; D007421:Intestine, Small / Q000382:microbiology; D009395:Nephritis, Interstitial / Q000209:etiology* / Q000378:metabolism; D019384:Nucleic Acid Synthesis Inhibitors / Q000009:adverse effects; D012294:Rifamycins / Q000009:adverse effects; D000078262:Rifaximin; D012595:Scleroderma, Systemic / Q000150:complications*
chemical_list: D019384:Nucleic Acid Synthesis Inhibitors; D012294:Rifamycins; D002129:Calcium Oxalate; D000078262:Rifaximin