Journal of Blood Disorders & Transfusion

Primary cold agglutinin disease (CAD) associated lymphoproliferative disease: A new entity

3^rd International Conference on Hematology & Blood Disorders

November 02-04, 2015 Atlanta, USA

Ulla Randen

Oslo University Hospital, Norway

Scientific Tracks Abstracts: J Blood Disord Transfus

Abstract:

Primary chronic cold agglutinin disease (CAD) is a rare hemolytic disease (1:1.000.000) mediated by monoclonal IGHV4-34- encoded cold agglutinins with a predominant specificity for the blood group antigen I. These patients have previously been given a variety of diagnoses on bone marrow biopsies, from �??no signs of lymphoid infiltration�?? to an overt lymphoma, most often lymphoplasmacytic lymphoma (Mb. Waldenström). However, studies including flow cytometry have shown that >90% of them, if not all, have a monoclonal B-cell proliferation. We have therefore performed studies on a larger group of CAD patients and examined bone marrow aspirates and biopsies to better type the underlying lymphoproliferative disorder. Bone marrow biopsies typically showed small infiltrates (median infiltration: 10% of marrow cells) with a mature B-cell immunophenotype. Morphologically, the infiltration did not fit with lymphoplasmacytic lymphoma, as neither mast cells nor plasmacytoid cells were present, nor did the small B-cells express plasma cell differentiation-associated markers. A limited number of mature monoclonal IgM+ plasma cells were present outside the lymphoid nodules and were diffusely scattered throughout the marrow and regarded as part of the lymphoproliferative disease, as these produce the monoclonal anti-I antibodies. Of interest, the MYD88 L265P mutation, typical of lymphoplasmacytic lymphoma was not detected. We conclude that cold agglutinin-associated lymphoproliferative disease displays homogeneous histological and immunophenotypic features that distinguishes this entity from lymphoplasmacytic lymphoma and thereby distinguishes chronic cold agglutinin disease from Mb. Waldenström.

Biography :

Ulla Randen is a Consultant Pathologist at Oslo University Hospital with a specialty in Hematopathology including Flow Cytometry. She has performed research on different small B-cell lymphoproliferative diseases with a special interest in patients with chronic cold agglutinin disease (CAD).

Email: uranden@ous-hf.no