Abstract: SA-PO0325
Digging Deeper: A Novel Etiology of Oxalate Nephropathy
Session Information
- AKI: Case Reports - Drug/Toxin Injury, Crystals, Obstruction, and Unusual Presentations
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Shehzad, AbdulMoid, Washington University in St Louis, St. Louis, Missouri, United States
- Bellas, Andrew James, Washington University in St Louis, St. Louis, Missouri, United States
- Sanchez, Juan E., Washington University in St Louis, St. Louis, Missouri, United States
- Goldberg, Seth, Washington University in St Louis, St. Louis, Missouri, United States
Group or Team Name
- Stone
Introduction
Oxalate nephropathy is a rare cause of kidney injury, accounting for ~1% of native kidney biopsies, with over half of affected patients progressing to kidney failure. The condition results from calcium oxalate crystal deposition within renal tubules and interstitium, triggering direct epithelial injury, tubular obstruction, and fibrosis. Causes include increased intestinal oxalate absorption or excessive exogenous oxalate intake, though the etiology is unknown in up to 17% of cases.
Case Description
We report the case of a 52-year-old female patient with a history of schizophrenia hospitalized with lethargy. Presenting blood pressure was 79/56, plasma creatinine 13.4 mg/dL (baseline 1.6-1.9), BUN 217 mg/dL, bicarbonate 16 mmol/L, anion gap 32. She was non-verbal on exam. Urine showed many WBCs, non-dysmorphic RBCs, no casts, no crystals. Ultrasonography and serologic workup were unrevealing. Despite fluid resuscitation, she remained anuric. Hemodialysis was started, with mental status recovering to baseline. Renal biopsy showed multiple polarizable calcifications within the tubules, consistent with calcium oxalate.
On further questioning, the patient revealed that she had been ingesting potting soil for 2 years, after a 42-year history of eating regular dirt. She estimates eating up to 1 cup/day, but increased to 2-3 cups/day over the 2 months prior to admission. She confirmed this to be “MiracleGro Potting Mix” when shown a picture of the product. The patient did not recover renal function and remained dialysis-dependent.
Discussion
Diagnosis of oxalate nephropathy is frequently delayed because the presentation is nonspecific and the underlying source of exposure is often not apparent. Geophagia, the ingestion of soil or clay, is a well-described subtype of pica associated with psychiatric comorbidities. Although soil and composted organic matter contain calcium oxalate as a fungal metabolic by-product, the link between soil or potting mix ingestion and oxalate nephropathy has not been previously reported.