Confirmed Cryoglobulinemia and Hyperviscosity Syndrome Secondary to Multiple Myeloma-IgA Kappa from Routine Blood Test: a Case Report.

Background: Cryoglobulins and hyperviscosity syndrome (HS) sometimes occur in multiple myeloma (MM), which are considered clinical emergencies. In laboratory practice, aspiration failure in routine blood tests sometimes occurs when the sample is inadequate. Here, a case of cryoglobulinemia and HS associated with advanced multiple myeloma was reported, which unusually is initially confirmed by aspiration failure in a routine blood test with sufficient sample. Methods: A case of a 48-year-old female whose diagnosis of cryoglobulinemia and hyperviscosity syndrome secondary to MM-IgA kappa was confirmed from routine blood test. Results: The sufficient sample for routine blood test could not be analyzed in a hematology analyzer due to aspiration failure, which was found to be caused by high viscosity and poor liquidity. A peripheral blood smear showed numerous non-cellular clouds, erythrocyte rouleaux formation, and plasma cell infiltration. After a water bath, the non-cellular clouds evidently disappeared, and the routine blood test was successfully conducted. Centrifugation of the sample for biochemical test, which had previously failed, was also possible. The case was confirmed as complications of cryoglobulinemia and HS associated with advanced MM, and the non-cellular clouds were identified as cryoglobulins. Conclusions: This case report provides an effective way for clinicians to deal with this kind of abnormal sample and limited but important laboratory evidence to establish early diagnosis of cryoglobulinemia and HS secondary to MM.