A Case of Elevated Troponin I Level After Packed Red Blood Cell Transfusion With Normal Coronary Angiography

Area of Science:

• Clinical Biochemistry
• Cardiology
• Laboratory Medicine

Background:

• Elevated cardiac troponin I (cTnI) levels are a key biomarker for acute coronary syndrome (ACS).
• However, numerous non-ACS clinical conditions, including pulmonary embolism, heart failure, myocarditis, sepsis, and renal failure, can also elevate cTnI.
• Analytical interferences, such as fibrin clots, heterophile antibodies, and hemolysis, can lead to falsely elevated cTnI results.

Observation:

• A 66-year-old female presented with pleuritic chest pain.
• Following transfusion of three units of packed red blood cells, her cTnI level was measured at 35.5 ng/mL.
• A comprehensive evaluation for ACS, including coronary angiography, was negative for obstructive coronary artery disease.

Findings:

• The elevated cTnI level in this patient was not attributable to acute coronary syndrome.
• Post-transfusion laboratory interference is a potential cause of elevated cTnI, mimicking cardiac ischemia.
• This case underscores the importance of considering analytical interferences in the interpretation of cTnI results.

Implications:

• Clinicians should consider non-ischemic causes and analytical interferences when interpreting elevated cTnI levels, especially in the post-transfusion setting.
• Careful patient history and sample assessment are crucial to avoid misdiagnosis of ACS.
• Further investigation into transfusion-related interferences with cTnI assays may be warranted.