Coulter S Plus STKR histograms detect spurious elevation of leucocyte and platelet counts associated with cryoglobulinaemia.

Abnormalities in the size frequency histogram generated by the Coulter S Plus STKR at room temperature raised the possibility of the presence of a cryoglobulinaemia in a man admitted to the hospital with pneumonia. The leucocyte and platelet counts generated by the Coulter S Plus STKR were higher when counts were done at room temperature than counts done at 37 degrees C. Further investigation of the patient revealed the presence of Non-Hodgkin's Lymphoma which had not been suspected on clinical grounds. The importance of testing samples at 37 degrees C, where an abnormality in the Coulter S Plus STKR histogram has been detected at room temperature, is emphasized.