Thermally induced popcorn red blood cells

A 1-year-old baby was admitted to the hospital after severe burns. He was critically scalded on up to half of his corporal surface. Automated analyzer (Advia 2120, Siemens Healthcare Diagnostics, Deerfield, IL) histograms indicated red blood cell (RBC) anomalies (anisocytosis, microcytosis, hyperdense RBCs) and platelet count artifactual increase at 1.200 x 10 9 /L. The blood smear showed (see figure, left, mosaic image, May Griinwald Giemsa staining, x630) anisopoikilocytosis with numerous fragments but no real shistocytes, microspherocytes, and membrane blebs with vesiculation. RBCs appeared characteristically to be budding off very small fragments. This peculiar picture of physaliferous RBCs is highly associated with severe thermal burns. It can be also observed after chemical injury when an exothermic reaction occurs. 1 We were able to obtain similar pictures heating control RBCs at 56°C for 100 seconds (see figure, right, mosaic image). Heat-induced degenerative changes have previously been reported with microwave treatment of RBCs 2 and might be used for experimental evaluation of automated blood cell counters to determine sphering, budding, and even fragmentation, 3 although thermal damage alone is not expected to cause the formation of schistocytes.