Cryoglobulinemia has been reported rarely to cause false elevation in platelet and/or leukocyte counts due to temperature-dependent protein precipitates that interpreted as blood cells at room temperature. Upon heating to 37°C, these blood counts decrease to normal levels as cryoproteins dissolve. Here, we report two cases with this rare phenomenon that may lead to inappropriate investigations in clinical practice and have diagnostic significance when kept in mind.

Cryoglobulinemia has been reported rarely to cause false elevation in platelet and/or leukocyte counts due to temperature-dependent protein precipitates that interpreted as blood cells at room temperature. Upon heating to 37°C, these blood counts decrease to normal levels as cryoproteins dissolve. Here, we report two cases with this rare phenomenon that may lead to inappropriate investigations in clinical practice and have diagnostic significance when kept in mind.