Which of the following is a cause for false-elevated ESR values?

The cause for false-elevated erythrocyte sedimentation rate (ESR) values is typically associated with the presence of anemia. When anemia is present, particularly in its inflammatory or chronic forms, it can lead to changes in the plasma composition, which in turn affects the sedimentation of red blood cells.

In states of anemia, there can be an increase in the number of acute phase reactants, such as fibrinogen, that enhance the aggregation of red blood cells. This aggregation leads to a faster sedimentation rate, which results in falsely elevated ESR values. Additionally, anemia may cause a decrease in red cell mass relative to plasma volume, allowing for more pronounced sedimentation effects.

While the other factors mentioned can influence ESR readings, they do not directly lead to a significant elevation in values like anemia does. For instance, while decreased temperature of the specimen might influence the rate slightly, it would not specifically cause a false elevation. A decrease in cytokines generally would not support the inflammatory response that raises the ESR, and while a high platelet count may have some relationship with inflammation, it is not a direct cause of falsely elevated ESR in the same way as anemia.