Lipemia-Induced Hemoglobin Overestimation and Correction by Plasma Replacement in a Pediatric Acute Lymphoblastic...

Pre-analytical and analytical errors in laboratory testing can lead to clinical misinterpretation. This case highlights a falsely elevated hemoglobin level due to lipemia and the corrective laboratory intervention.

A 3-year-7-month-old girl with acute lymphoblastic leukemia underwent a follow-up complete blood count which reported a hemoglobin level of 16.9 g/dL. The hemoglobin result was inconsistent with previous clinical findings and hematocrit. A simultaneously drawn venous blood gas sample showed a hemoglobin value of 9.2 g/dL. The biochemistry sample showed visible lipemia, with a lipemia index of 3041. The same sample revealed a triglyceride level of 8042 mg/dL (1:50 dilution) and total cholesterol of 492.2 mg/dL. These findings indicated a falsely elevated hemoglobin due to lipemia. The patient was not on parenteral nutrition. Pediatric endocrinology consultation attributed lipemia to L-asparaginase and corticosteroids in the treatment regimen. To eliminate lipemic interference, the EDTA blood sample was centrifuged at 1000 x g for 10 minutes, and the lipemic plasma was replaced with an equal volume of 0.9% NaCl solution. The sample was gently mixed to restore whole blood integrity. After this plasma replacement procedure, hemoglobin was measured as 10.2 g/dL, consistent with the blood gas result and clinical picture.

This case emphasizes the need to correlate laboratory results with clinical and biochemical data. In lipemic samples, plasma replacement may provide a practical correction method for falsely elevated hemoglobin values when resampling is not feasible. Recognition and prompt correction of lipemia-induced errors are crucial to avoid inappropriate clinical decisions.