Laboratory Detection of Pseudohyperkalaemia in a Trauma Patient: A Case Report

Pseudohyperkalaemia refers to a spuriously elevated serum potassium concentration resulting from laboratory artefacts and frequently poses a diagnostic and therapeutic challenge in routine clinical practice. Its significance is heightened in acute care settings, where timely and appropriate clinical decisions are critical. The present report describes the case of a 53-year-old male who developed pseudohyperkalaemia following polytrauma with extensive lower limb injuries, including a crush injury to the left foot. Initial potassium levels were within the normal range; however, subsequent elevations were observed in the absence of Electrocardiographic (ECG) changes or clinical features suggestive of true hyperkalaemia. Further evaluation revealed thrombocytosis, a recognised cause of pseudohyperkalaemia due to potassium release from activated platelets during clot formation. The present case is notable because the diagnostic dilemma occurred in a critically injured trauma patient, where differentiating true hyperkalaemia from pseudohyperkalaemia had significant therapeutic implications. Prompt recognition prevented unnecessary administration of potassium-lowering therapy, which could have resulted in iatrogenic hypokalaemia. Correlation of laboratory findings with clinical assessment, along with the use of plasma rather than serum samples, aided in confirming the diagnosis. The present report highlights the importance of maintaining a high index of suspicion for pseudohyperkalaemia in patients with thrombocytosis or leukocytosis, particularly in trauma and critical care settings. Awareness of this phenomenon can prevent mismanagement, enhance patient safety, and guide rational treatment decisions.