Published online by Cambridge University Press: 11 July 2009
INTRODUCTION
In 1952, Jan Waldenström introduced the term “essential hyperglobulinemia” to describe patients with a small spike in the electrophoretic pattern but no evidence of multiple myeloma (MM), Waldenström macroglobulinemia (WM), amyloidosis (AL), or related disorders. Benign, idiopathic, asymptomatic, nonmyelomatous, cryptogenic, lanthanic, and rudimentary monoclonalgammopathy; dysimmunoglobulinemia; idiopathic paraproteinemia; and asymptomatic paraimmunoglobulinemia have been used to describe the entity. According to Waldenström, the protein spike remained constant in size in contrast to the increasing protein spike of the protein in MM. The entity became known as “benign monoclonal gammopathy,” but this is misleading because a monoclonal (M) protein may remain stable or it may increase and develop into symptomatic MM, WM, AL, or a related disorder. Because of this, the term “monoclonal gammopathy of undetermined significance” is a more appropriate term.
Monoclonal gammopathy of undetermined significance (MGUS) is characterized by the proliferation of a single clone of plasma cells that produces a homogeneous monoclonal (M) protein. Each M protein consists of two heavy polypeptide chains of the same class and subclass and two light chain polypeptide chains of the same type. In contrast, polyclonal immunoglobulins are produced by many clones of plasma cells. They contain all heavy chain classes and both light chain types. Each M protein consists of two heavy polypeptide chains of the same class: gamma (γ) constitutes immunoglobulin G (IgG), alpha (α) is found in IgA, mu (μ) is present in IgM, delta (δ) occurs in IgD, and epsilon (ε) is present in IgE.
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.