Clotted blood tube
(Serum gel separator clot activator tube)
Minimum blood volume: 5 mL
24 Hr urine:
U1 bottle
Paediatric clotted blood tube
Number of vials: 3
Minimum blood volume: 2.4 mL
Authorisation code required
No
No
24 Hr available service
No
No
Method
Electrophoresis on agarose gel, with interpretation by inspection
Quantitation of bands, if appropriate, by densitometry
Reference interval
See result interpretation session.
Clinical indication
Serum:
Detection and quantitation of paraprotein bands in e.g. multiple myeloma, Waldenström macroglobulinaemia and some lymphoproliferative
disorders
Less specific patterns are seen in association with liver disease, infection, other inflammatory states, nephrotic syndrome or specific protein deficiencies.
Urine:
Detection of light chain (Bence Jones) proteinuria and investigation of monoclonal gammopathies, hypogammaglobulinaemia, and suspected multiple myeloma (performed in conjunction with serum protein electrophoresis)
Assessment of protein selectivity in renal glomerular disease
24 Hr urine:
To quantitate excretion of light chains and other proteins
Result interpretation
The serum protein pattern may be visually interpreted by comparing the sample pattern with a control pattern. With the use of a densitometer, the relative percentage of each protein zone may be calculated. In either method, the presence of extra serum components or an increase or absence of normally occurring serum components indicates the necessity for further protein analyses. (Please see immunofixation electrophoresis.)
The first line investigation for suspected myeloma is serum protein electrophoresis. Urine protein electrophoresis for Bence Jones protein is only performed for prognostic purpose, or when Bence Jones myeloma is strongly suspected.
Monoclonal light chain proteinuria (Bence Jones proteinuria) is seen in patients with light chain myeloma, in approximately 50% of those with IgG and IgA myeloma, and in some patients with other lymphoproliferative disorders (e.g. macroglobulinaemia) and plasma cell dyscrasias (amyloid).
The electrophoretic pattern may also be helpful to distinguish glomerular from tubular proteinuria.
Measurement of uncertainty
Frequency of measurement
weekly