Title: A Unique Case Report of High-Anion-Gap Metabolic Acidosis with Pseudohyponatremia in Setting of Hypertriglyceridemia

Author(s): Rupalakshmi Vijayan, MD; Elizabeth Herrera Perez, MD; Ghazaleh Bigdeli, MD; Kathleen Padgitt, MD; Milad Saleh Abusag, MD

Introduction:  In cases of hypertriglyceridemia, spurious low values of bicarbonate can occur mainly due to lipolysis-induced hydrogen ions displacing bicarbonate molecules. There is a lab discrepancy between ABG and BMP panels because of TGL molecules scattering light in photometric analysis of blood tests.

Case: A 38-year-old male with significant past medical history of alcohol abuse, essential hypertension, gastritis, ADHD who was sent as he was told he looked yellow. Patient had a long history of alcohol abuse and familial history of hypercholesterolemia.

Initial lab work in the ER done showed severe hyponatremia with sodium 113, chloride of 75 a bicarb less than 2, creatinine 1.7 and a gap was not able to be calculated. The patient had a lactic acid of 5.3. LFTs showed an alk phos of 808 ALT of 159 AST of 360 total bilirubin of 17. His alcohol level was elevated to 221. CBC showed a WBC of 5.7 H&H of 8.8/26 point MCV of 2.6 with a platelet count of 165. On further assessment, electrolyte repletion was started, and nephrology was consulted. Despite bicarbonate repletion, bicarbonate levels in blood remained low but ABG showed normal pH of blood and near normal bicarb levels. Hence, lipid panel was ordered. Lipid panel showed elevated TGL and cholesterol. Endocrinology was then consulted, and they suggested insulin drip to lower TGL levels and long-term lipid lowering agents to reduce TGL levels for clinical improvement of the patient.

Conclusion: Clinical suspicion of hypertriglyceridemia should occur when physicians note major discrepancies in laboratory values of venous and arterial blood studies of bicarbonate and electrolyte levels. Analyzers that use ion selective electrode method helps with more accuracy in lab values. Lipids are heavier molecules which reduce aqueous quality and increase turbidity of blood, falsely lowering electrolyte values. Considering hypertriglyceridemia as a differential diagnosis in electrolyte abnormalities is quintessential in regular clinical practice to help prevent unnecessary investigations and interventions.