Case report Capillary immunotyping electrophoresis and high resolution two-dimensional electrophoresis for the detection of μ-heavy chain disease V. Maisnar a, ⁎ ,1 , M. Tichy b,c,1 , J. Stulik b , P. Urban d , Z. Adam e , E. Kadlckova d , J. Vavrova c , V. Palicka c , L. Jebavy a,b , R. Kodet g , T. Buchler f,1 , R. Hajek e,1 a 2nd Department of Internal Medicine - Division of Clinical Haematology, Charles University Hospital, Hradec Králové, Czech Republic b Faculty of Military Health Sciences, Hradec Králové, University of Defence, Brno, Czech Republic c Institute of Clinical Biochemistry and Diagnostics, Charles University Hospital, Hradec Králové, Czech Republic d Department of Clinical Biochemistry, Bat'a Hospital, Zlín, Czech Republic e Department of Internal Medicine - Haematooncology, University Hospital, Brno, Czech Republic f Department of Oncology, Thomayer University Hospital, Prague, Czech Republic g Institute of Pathology and Molecular Medicine, Charles University Hospital, Prague, Czech Republic Received 6 September 2007; received in revised form 30 October 2007; accepted 30 October 2007 Available online 6 November 2007 Abstract Heavy chain disease with monoclonal incomplete μ-heavy chains (μ-HCD) is a rare disorder usually associated with an underlying lymphoproliferative malignancy. Laboratory diagnosis of patients with μ-HCD is usually challenging and the monoclonal protein is not detected by electrophoresis in up to 75% of μ-HCD cases. We describe a patient with multiple malignancies in whom we detected and characterized monoclonal μ-heavy chains using immunofixation electrophoresis, capillary zone electrophoresis with immunotyping, and high resolution two- dimensional electrophoresis. The high resolution 2D electrophoresis enabled us to determine the molecular weight of the μ-heavy chains. The abnormal protein concentration in the serum was unusually high, 38 g/l measured in our patient is the highest reported value in the literature so far. © 2007 Elsevier B.V. All rights reserved. Keywords: μ-Heavy chain disease; Diagnosis; Capillary zone electrophoresis; 2-Dimensional electrophoresis 1. Introduction Heavy chain diseases are characterized by proliferation of a single clone of B-lymphocytes that produces structurally ab- normal (incomplete) immunoglobulin (Ig) heavy chains without association with light chains [1,2]. Laboratory diagnosis of patients with heavy chain disease is usually challenging. The pathological protein is not detected during electrophoresis in about 20% of observed patients with heavy chain γ, in 50% of observed patients with heavy chain α and in up to 75% patients with μ-heavy chain disease [2]. Immunoelectrophoresis and immunofixation provide only indirect evidence for the presence of free heavy chains by showing a band reacting with heavy but not with light Ig chains. Immunoselection has been used as the gold standard for diagnosis of heavy chain disease [3]. Two-dimensional (2D) gel electrophoresis is useful in this situation because of its high resolution and the possibility to determine the molecular weight of the monoclonal protein [4]. We report on a patient with μ-heavy chain disease (μ-HCD) diagnosed using capillary zone electrophoresis (CZE) with im- munotyping and high resolution 2D electrophoresis followed by immunoblotting. 2. Case report A 63-year-old woman was initially diagnosed with vulvar carcinoma and treated with chemotherapy and radiotherapy. Ten Available online at www.sciencedirect.com Clinica Chimica Acta 389 (2008) 171 – 173 www.elsevier.com/locate/clinchim ⁎ Corresponding author. 2nd Department of Internal Medicine - Division of Clinical Haematology, Charles University Hospital, Sokolská 581, 500 05 Hradec Králové, Czech Republic. Tel.: +420 495833848; fax: +420 495832011. E-mail address: maisnar@seznam.cz (V. Maisnar). 1 Czech Myeloma Group, Czech Republic. 0009-8981/$ - see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.cca.2007.10.035