title: A case of IgD myeloma representing a missed biclonal paraproteinemia or isotype switch in a patient previously diagnosed with IgA-lambda myeloma.
abstract: BACKGROUND
  Multiple myeloma is a clonal plasma cell neoplasm that is identified in the laboratory by a presence of a monoclonal immunoglobulin or increased plasma light chain levels.
  
  
  METHODS
  The most commonly identified and tested immunoglobulins are IgA, IgG and IgM.
  
  
  RESULTS
  Rare cases of multiple myeloma present with monoclonal IgD and IgE paraproteins.
  
  
  CONCLUSIONS
  We present a case of IgD myeloma diagnosed in a patient who had achieved partial remission from a previously diagnosed IgA myeloma, possibly representing a missed biclonal paraproteinemia or isotype switch after treatment.
authors: Mount Sinai Hospital, Dept of Pathology, Gustave L Levy Place, Box 1194, New York, NY 10128, USA. Electronic address: juliechepovetsky@gmail.com.
authors: Julie
authors: J
authors: Chepovetsky
authors: Ajai
authors: A
authors: Chari
authors: Sundar
authors: S
authors: Jagannath
authors: Lakshmi
authors: L
authors: Ramanthan
mesh_terms: D000328:Adult; D002999:Clone Cells; D057210:Delayed Diagnosis; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood*; D017578:Immunoglobulin Class Switching; D007072:Immunoglobulin D / Q000097:blood*; D007146:Immunoglobulin lambda-Chains / Q000097:blood*; D008297:Male; D009101:Multiple Myeloma / Q000097:blood / Q000175:diagnosis* / Q000276:immunology
chemical_list: D007070:Immunoglobulin A; D007072:Immunoglobulin D; D007146:Immunoglobulin lambda-Chains
keywords: Biclonal myeloma; IgD; Immunofixation; Isotype switch; Multiple myeloma