PT  - JOURNAL ARTICLE
AU  - Avashia, Jay H.
AU  - Walsh, T. Declan
AU  - Valenzuela, Rafael
AU  - Quevedo, J. Fernando
AU  - Clough, John
TI  - Pseudohypoproteinemia and multiple myeloma
DP  - 1990 May 01
TA  - Cleveland Clinic Journal of Medicine
PG  - 298--300
VI  - 57
IP  - 3
4099  - http://www.ccjm.org/content/57/3/298.short
4100  - http://www.ccjm.org/content/57/3/298.full
SO  - Cleve Clin J Med1990 May 01; 57
AB  - Paraproteinemia is an important diagnostic feature of multiple myeloma. The M-protein level reflects tumor burden and helps to determine the response to chemotherapy. A case is described that illustrates the phenomenon of reversible in vitro gelification of an M-protein. Paraprotein IgG,-kappa formed a concentration- and temperature-dependent gel, which was reversed by agitation. Measurement of paraprotein without previous vortexing of the specimen can erroneously lower the apparent M-protein level as well as reduce serum viscosity levels. This phenomenon can downstage the disease at diagnosis, produce inappropriate assessment of treatment response, or lead to premature withdrawal of chemotherapy. In addition, misdiagnosis of hyperviscosity syndrome can occur with serious clinical consequences.