What is a key requirement for patient preparation before infection imaging with tagged white blood cells?

The key requirement for patient preparation before infection imaging with tagged white blood cells involves gathering lab work and information about recent blood transfusions. This is essential because tagged white blood cell scans are used to identify infections, and recent blood transfusions can interfere with the accurate interpretation of the imaging results. The presence of transfused cells can obscure the location and severity of an infection by introducing foreign cells that may create misleading imaging findings. Therefore, having a clear understanding of a patient's transfusion history, including timing, helps in assessing the imaging results accurately and ensuring optimal diagnostic efficacy.

In this context, while fasting, medication discontinuation, or smoking cessation may be relevant in other medical imaging scenarios, they do not hold the same significance for tagged white blood cell imaging. The procedural effectiveness and accuracy of the scan rely heavily on understanding the patient's hematological background, particularly in relation to any recent transfusions.