Pseudospontaneous Platelet Aggregation and Spuriously Elevated Blood Cell Counts in Cryoglobulinemia

Cryoglobulinemia has been reported sometimes to cause false elevation in platelet and/or leukocyte counts in au tomated blood cell counters due to temperature-dependent pro tein precipitates that are falsely interpreted as blood cells at room temperature. Upon heating to 37°C, these blood counts decrease to normal levels as cryoproteins dissolve. Therefore, cryoglobulins could theoretically lead to erroneous diagnosis of spontaneous platelet aggregation in platelet counting and tur bidometric methods as platelet count and turbidity of the plate let-rich plasma decrease at 37°C, respectively. Here, the event of pseudospontaneous platelet aggregation is confirmed in two patients with mixed cryoglobulinemia, both had spuriously el evated blood cell counts.