Pseudo-Blood Leak Alarm and Pseudo-Lactic Acidosis: A Hydroxocobalamin-Ethylene Glycol Combination

Introduction: Blood leak alarms exist on intermittent hemodialysis machines to prevent contaminated blood from returning to the patient when errors occur. While the risk of this occurring is low, hydroxocobalamin has been linked with causing pseudo-blood leak alarms. Ethylene glycol intoxication, while deadly, has been associated with pseudo-lactic acidosis on whole blood analysis. We present a case of a pseudo-blood leak and pseudo-lactic acidosis from hydroxocobalamin and ethylene glycol. Case Description: A 23-year-old female presented to the hospital for encephalopathy. Initial labs revealed: potassium of 6.5 mmol/L, chloride of 112 mmol/L, bicarbonate of 5 mmol/L, Blood Urea Nitrogen of 11 mg/dL, and serum creatinine of 1.11 mg/dL. Venous blood gas revealed a pH of 6.8 and pCO2 of 21. The whole blood analysis lactate was 26 mmol/L; however, serum lactate was 2.4 mmol/L. Due to concern for acute cyanide ingestion, the patient was given hydroxocobalamin. Serum osmolality was 326 mOSM/KG, with an osmolar gap of 29. Ethylene Glycol level was 31 mg/dL. Urine microscopy revealed calcium oxalate monohydrate crystals. Given acute intoxication with ethylene glycol, fomepizole was administered, and intermittent hemodialysis was initiated with a Fresenius 2008T hemodialysis machine. A blood leak alarm then occurred. A second Fresenius 2008T was used, however a recurrent blood leak alarm triggered. The patient was transitioned to continuous kidney replacement therapy with NxStage, which functioned appropriately. The patient survived and was weaned from kidney replacement therapy. Discussion: This case presents a phenomenon of hydroxocobalamin-induced blood leak alarms in certain intermittent hemodialysis machines. Given the increase in use of hydroxocobalamin, as it is deemed a safe treatment for cyanide poisoning, treatment of other toxic ingestions with dialysis may be impacted. This may lead to a delay in appropriate treatment for toxic ingestions as it may disrupt the ability to start clearance of toxins by dialysis. Pseudo-lactic acidosis can occur during ethylene glycol breakdown and excretion, as glycolic acid is created. Glycolic acid is reported as lactic acid on whole blood analysis, causing a pseudo-lactic acidosis, which is not present when measured in serum lactic acid levels.