FRI095 Pseudo Anion Gap Metabolic Acidosis Secondary To Severe Hypertriglyceridemia

Disclosure: G.C. Connery: None. S. Ward: None. K.E. Izuora: None. A. Champion: None. Background/Objective: Severe hypertriglyceridemia can falsely alter multiple lab parameters due to the high lipid fraction of the blood sample. We present a patient who initially presented with severe metabolic acidosis but proved to have normal pH and bicarbonate after correction for hypertriglyceridemia. Case Report: A 34-year-old female with past medical history of recurrent acute on chronic pancreatitis secondary to hypertriglyceridemia, type 2 diabetes, obesity, and hypertension presented to the emergency department with epigastric pain. The patient was initially diagnosed with acute pancreatitis, diabetic ketoacidosis (DKA), and hyponatremia. Initial labs showed sodium 116 mmol/L, glucose 617 mg/dL, bicarbonate < 5 mmol/L, blood ketones 0.8 mmol/L, lactic acid 2.57 mmol/L, and creatinine 0.95 mg/dL. A venous blood gas (VBG) revealed pH 7.42, pCO2 36 mmHg, pO2 62 mmHg, and bicarbonate 24 mmol/L. Her lipid panel revealed triglyceride levels > 4000 mg/dL. The discrepancy in bicarbonate levels between the blood chemistries and VBG were attributed to a pseudo-anion gap metabolic acidosis secondary to her hypertriglyceridemia. After treatment with insulin infusion, hypertriglyceridemia resolved and her bicarbonate levels on renal function panel normalized. Discussion: The high lipid fraction of blood plasma in patients with severely high triglyceride levels can confound other laboratory parameters. Pseudo hyponatremia secondary to elevated triglycerides is one example of a commonly known lab abnormality. In our patient, her initial bicarbonate levels on renal function panel led to concern for severe metabolic acidosis that was not consistent with her mild blood ketones and lactic acid levels. Further investigation with VBG revealed normal pH and bicarbonate levels. Conclusion: Severe hypertriglyceridemia may significantly alter bicarbonate measurement on blood chemistries. Further investigations with blood gasses should be pursued to confirm these abnormalities when suspected. Presentation: Friday, June 16, 2023