The presence of serum cold agglutinin can be the initial presentation of lymphoproliferative diseases. Conditions with persistent cold agglutinins are a spectrum of diseases that vary from benign lymphoproliferation of the "autoimmune-like chronic cold agglutinin disease" to malignant lymphoma. We report a case of a 72-year-old woman who presented with severe anaemia, hepatosplenomegaly and episodes of peripheral haemagglutination precipitated by cold exposure. The haemoglobin was 5.6 g/dL with a cold agglutinin titer of 1:256 at 4 degrees C and 1:8 at room temperature (30 degrees C). The cold agglutinin showed anti-I specificity and kappa light chain restriction. Peripheral blood showed atypical lymphoid cells with a B-cell immunophenotype. Immunoglobulin gene rearrangement study by polymerase chain reaction (PCR) showed an amplified band at 100 bp, consistent with a clonal proliferation of B-lymphocytes. We believe that our patient had cold antibody haemolytic anaemia as the initial presentation of a low-grade non-Hodgkin's lymphoma. The association of cold antibody haemolytic anaemia with low-grade B-cell lymphoma is unusual.
Rearrangement of the immunoglobulin heavy chain (IgH) gene has been used as a marker of lineage and clonality in the diagnosis of B lymphoproliferative disorders. A number of PCR-based techniques have been developed to overcome the disadvantages of Southern blotting, the standard technique in detecting IgH gene rearrangement. Using an established seminested PCR technique with consensus primers to the V and J regions of the IgH gene, we analysed DNA prepared from peripheral blood and/or bone marrow specimens from 30 cases of known B cell malignancies (16 chronic lymphocytic leukemia, 11 acute lymphoblastic leukemia and 3 Non-Hodgkin Lymphoma), 3 cases of T lymphoproliferative disease and 3 cases of reactive lymphocytosis diagnosed in Hospital UKM to detect rearranged IgH gene. We found that monoclonality as represented by the presence of rearranged IgH gene were demonstrated in all the 30 cases. The PCR findings showed 100% concordance with the Southern blot analysis results which also showed rearranged IgH bands in all the 30 cases. We also found that none of the cases of T lymphoproliferative diseases and reactive lymphocytosis showed presence of rearranged IgH band, suggesting that the amplification using the IgH primers is lineage-specific. In conclusion, we find the PCR a useful method to detect IgH gene rearrangement in peripheral blood and bone marrow specimen. Since the PCR results are comparable to that of the Southern blotting in demonstrating B cell monoclonality and owing to its many advantages we feel that it can replace the Southern blot technique for the diagnosis of B cell malignancies.