| |
|
|
| |
|
|
| |
|
| |
electrophoretic methods - electrophoresis and immunofixation |
| |
| Reproducibility of the results, even
for the same commercial method, although gradually
improving as the studies advance, it
is still insufficient, particularly for low concentrations
and clearly inferior to that of nephelometry and turbidimetry.
Collaboration is required with producers to achieve a
necessary better standardization of electrophoretic methods
in general.
The sensitivity of commercial Electrophoresis
(EPh) and Immunofixation (IFX), on the samples examined,
is inferior to nephelometry and turbidimetry.
Detection limit should be comparable to those of immunochemical
methods (around 0.5 mg/dl) |
| |
|
| |
| immunochemical methods – nephelometry and turbidimetry |
| |
Reproducibility of results, in all
studies performed, is confirmed as very good,
even for low concentrations with all the reagents used.
Sensitivity is very good, both with
reagents for “Total” Light Chains (Bound and
Free Light Chains) and those for Free Light Chains.
Expression of the “Total” Light Chain result
is formally different between Behring and Beckman on a
3.33 factor. Uniformity would be convenient.
|
| |
|
| |
| operational recommendations |
|
Meetings held after the experiments have allowed the
two “most advanced” groups to formalize some
“Operational Recommendations” drafts: |
| |
|
| Their document proposes
some base characteristics which the methods and protocols
used for BJP qualitative and quantitative determination
should comply with. |
| |
|
| |
Their document integrates
the above and complementing it with two proposals:
• mask for the report
• assessment proposal for quantitative determination |
| |
|
| |
| considerations for the report |
| |
Given the focus multiplicity and different characteristics
of the routine methods used, it has been considered
convenient that the laboratory report should:
• clearly indicate the use of a “Screening
method” and in which case, detail
the need of a “confirmation test” in
the event of a positive result
• include information on sample
type and methods used, particularly
on their sensitivity, to achieve a starting
point base for comparing the results obtained from the different
laboratories
A specific report example, contemplating these considerations,
is that proposed by the “Liguria” commission |
| |
| “Liguria” Commission report proposal |
|
| |
Test Name: Bence Jones Protein
study
First level test:
Sample:
random urine, 24h urine, etc.
Method: EPh,
Nephel., etc. (sensitivity ???? mg/dl)
Result: [_]
Negative
[_] Confirmation test needed
(Waiting
time: ?????)
Confirmation test:
Sample: random
urine, 24h urine, etc.
Method: IFX
(detail characteristics) (sensitivity ???? mg/dl)
Result: ??????????????? |
| |
|
| |
| other “positive effects” |
| |
Other positive effects obtained thanks
to the strategy adopted with multicentric studies
are:
• Better “state-of-the-art” knowledge
and comparison of the participating laboratories
• Evidencing methods have turned out to be not very
reliable and subsequent abandon: Total Proteins
• Progressive improvement of the characteristics of
the methods used
• Advances in the BJP study uniformity
• Availability of samples verified in the multicentric
works and consequently the possibility of objective comparison
of the different methods available
• Possibility of applying and expanding the same strategy
and work methodology adopted to subsequent studies |
| |
|
|
|
|