The reporting process

· Serum protein electrophoresis (SPE) is commonly employed for both hospitalized subjects as well as for outpatients.

· The main purpose of the test is to detect the presence of monoclonal components, as well as to provide information concerning qualitative and semiquantative variations in the major plasma proteins.

Reporting

· SPE is a rather complex technique in terms of execution and interpretation.

· Further elements of complexity are determined the transmission of analytical data to the clinician by means of a document which clearly comunicates the obtained information.

Reporting

· From an analytical point of view, electrophoretic techniques (agarose gel, capillary) provide excellent electrophoretic patterns. Nevertheless, the post-analytical phase is still vague, as there is yet no real standardization both in the interpretation as well as in the reporting stages.

Interpretation of electrophoretic patterns

· Some remarks ought to be made regarding the interpretation of electrophoretic patterns.

· The first issue concern the appropriateness of the request: as specified by the SIBIOC Protein Study Group Document, Serum Protein Electrophoresis should mainly be aimed at detecting the presence of monoclonal components.

Interpretation of electrophoretic patterns

· Another crucial aspect concerns the reliability and reproducibility of the visual inspection of patterns.

· The operator's technical expertise, as well as the number of electropherograms analyzed on a daily basis and their pattern types, can undermine the diagnostic efficacy of these techniques.

Interpretation of electrophoretic patterns

· A final crucial consideration concerns the means by which the information is conveyed. Indeed, this information cannot only consist of numerical data, but should also be able to convey clear, extensive and homogeneous information to the clinician. This approach also highlights the professional expertise of laboratory staff.

Interpretation of electrophoretic patterns

· Differing visual ispections of poorly visible alterations may lead to contrasting interpretations of electrophoretic patterns across operators.

· The diffusion of mathematical softwares for electrophoretic pattern interpretation will a first step towards standardization. This is particularly true in the case of high-throughput sample analysis, where such softwares may provide interpretative aid.

Some remarks

· The diffusion of analytical methods employing agarose gel supports as well as  free phase (capillary) techniques render the use of cellulose acetate supports anachronistic and inefficient, due to their low sensitivity and specificity.

· Furthermore, a six zone electrophoretic separation is to be preferred, along with a good resolution of the beta1-beta2 fractions.

The Reporting Process

· Fractions should be reported as percentages, along with total protein concentration.

· Absence of abnormal features, relative to the presence of monoclonal components, should be reported in the following manner: "absence of abnormal features suggesting the presence of a monoclonal component, given the sensitivity of the method employed". Any qualitative or quantitative abnormalities should be reported, if observed.

The Reporting Process

· The previous note is aimed at overting legal medicine controversies. This is due to the possibility that laboratory staff may equivocate the absence of monoclonal components by SPE, which may subsequently be detected by means of immunofixation.

· Nevertheless, for screening purposes, the information obtained from the analysis of electrophoretic patterns should nevertheless be reported. Negative detection of monoclonal components must be clearly stated on the report.

The Reporting Process

· The possible presence of a monoclonal component must be clearly stated also using terms such as "net increase" or "homogeneous peak". Quantification should be performed when immunofixation reflex-testing is not offered by the laboratory. In this case, after the monoclonal component has been typed, the report should indicate both peak quantification as well as the identified monoclonal component.

The Reporting Process

· Monoclonal component quantification must always be performed upon initial detection, as well as during subsequent follow-ups. It must be expressed in terms of concentration and calculated as a percentage of total protein concentration.

·Due to their variability, these tests should always be performed in the same diagnostic center and with the same instrument.

·In case the electrophoretic system were to be replaced, these tests should be performed in parallel, running tests on both the old and the new analyzing platforms. Clinicians should be informed thereof.

The electropherogram

· The electropherogram may be attached to the report itself. An accurate comment including descriptive notes should be enclosed in the document.

· Undoubtedly, as like other diagnostic tests, the electropherogram will reflect the professionality of the laboratory staff.

Reporting IFE results

1) IFE is performed in order to characterize all new bands and to confirm monoclonality; during follow-up, IFE should not be repeated unless variations in electrophoretic mobility are observed. Conversely, upon appearance of additional bands, or if the paraprotein is no longer visible, a new IFE should be performed;

2) Small entity paraproteins in the non-gamma regions, or within polyclonal patterns, require IFE at each follow-up, in order to confirm their presence;

3) IFE is required to confirm the absence of a previously characterized paraprotein, in order to elaborate response criteria of remission. Generally, upon confirmation of complete remission, IFE is no longer required during follow-up, unless a new band is detected by electrophoresis, or if specifically requested by the clinician.

Reporting IFE results

4) If a paraprotein is detected in serum but the urine sample is unavailable, the report should include the following comment: "urine monoclonal component testing recommended".

5) Upon paraprotein detection in the urine, the presence of trace elements of intact  monoclonal components require the following comment to be included in the report: "serum monoclonal component testing recommended."

If only light chains are detected, the type of light chain should be reported, along with a statement indicating the presence of Bence-Jones Protein. The report should also include a further request of serum sample for serum immunofixation.

6) Problematic samples requiring the identification of small protein bands can be redirected to IFE reference laboratories for further IFE testing;

Final Remarks

· SPE is the appropriate method for monoclonal component detection and monitoring.

· The interpretation is also based on a set of criteria depending on the operator's experience and expertise, thus highlighting the importance of reporting comments homogeneously.

Final Remarks

· The appropriateness of the test requires its use for monitoring patients undergoing transplantation as well as in subjects treated with imunosoppressive drugs. It is also indicated for patients with demyelinating peripheral neuropathy, as the detection of a monoclonal component in such cases may be of aid in the diagnostic process.

Final Remarks

· From a proactive and personal perspective, I hold that SPE may also be extended to screening test for subjects above the age of 50, especially in light of literature studies reporting the incidence of MCs in over 4% of the population.

· Similarly to other diagnostic tests, it may be added to preventive medicine protocols.