A case of sodium chlorate poisoning mimicking hemolytic anemia

Abstract

Introduction：Sodium chlorate is a non-selective herbicide known to cause various toxic effects following oral ingestion, including hemolysis, methemoglobinemia, disseminated intravascular coagulation, and renal dysfunction. To date, no cases of sodium chlorate poisoning with delayed medical intervention have been reported in the medical literature.

Case presentation：A 67-year-old woman presented to her primary care physician with fatigue. She was found to have anemia, jaundice with predominantly indirect hyperbilirubinemia, acute kidney injury, and signs of enhanced fibrinolysis. She was referred to our hospital on the same day for further evaluation. Her serum appeared dark gray, and peripheral blood smear analysis revealed no schistocytes but did show ghost cells and spherocytes. Upon further history-taking, it was revealed that she had ingested an herbicide that contained 50％ sodium chlorate approximately 10 days prior. Her methemoglobin level was mildly elevated, at 3.3％. Continuous renal replacement therapy was initiated on hospital day 2, continued for one week, and then transitioned to intermittent renal replacement therapy. The renal replacement therapy was discontinued on day 17, and the patient was transferred to another facility on day 29.

Conclusion：We report a rare case of sodium chlorate poisoning that required differentiation from other causes of hemolytic anemia. Despite a 10-day delay, the renal dysfunction was reversible, thus highlighting the importance of considering toxic etiologies in patients with unexplained hemolytic anemia and acute kidney injury.