s e c t io n v i.
Serum Protein Electrophoresis
Serum immunofixation electrophoresis of two patients with monoclonal gammopathies. Pattern A represents IgG(/tr)
monoclonal gammopathy and pattern B represents IgA(/c) monoclonal gammopathy, as indicated by arrows. The
procedure consists of serum protein electrophoresis (SPE) separation, reaction of each track with the exception of SPE
with specific respective antiserum, followed by protein staining to make visible the respective bands.
presence of a homogeneous class of protein (Figures
VI- lc and VI-2). Such a pattern should be further
investigated using other laboratory and clinical
findings to rule out multiple myeloma.
Means of investigation include quantitation of im-
munoglobins, immunofixation electrophoresis to iden-
tify the class and type of monoclonal immunoglobulin
(Figure VI-3), bone marrow aspiration and biopsy to deter-
mine plasmacytosis, and radiological examination to iden-
tify osteolytic lesions. Multiple myeloma is a disorder of
neoplastic proliferation of a single clone of plasma cells in
the bone marrow that leads to overproduction of any one of
the five immunoglobulins (IgG, IgA, IgM, IgD, or IgE) or
light chains
or A). Less commonly, biclonal or triclonal
gammopathy also occurs. If the light chains are overpro-
duced, they pass through the glomeruli and appear in the
urine; this is known as
Bence Jones proteinuria.
In a given
individual, Bence Jones proteinuria refers to either
or A
light chains but not both. Persons over age forty may be
affected and the initial findings may include spontaneous
fractures, bone pain, anemia, or infections. Hypercalcemia
may be found after bone destruction. Multiple myeloma is
a progressive disorder and is usually fatal due to renal dam-
age and/or recurrent infections. Cytotoxic measures (e.g.,
melphalan, a nitrogen mustard) are used in the treatment
of multiple myeloma, and serum and/or urine monoclonal
immunoglobulin or light chain levels serve in monitoring
Although the monoclonal spike is usually observed in
region, it is occasionally seen in the
region. In
pregnancy, a monoclonal spike in the
region may be due
to elevated transferrin levels. A serum electrophoretic pat-
tern of hypogammaglobulinemia requires further studies
of serum and urine (e.g., immunoglobulin measurement
and immunofixation electrophoresis) to rule out multiple
myeloma. The presence of monoclonal immunoglobu-
lin in the serum is a characteristic feature of a majority
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