I do not understand what you are saying. You are switching up terms,
although I have not seen documentation of false positives. Obviously,
you can have seminal fluid without spermatozoa. You can get Acid
Phosphatase (AP) positive with a female from the glands of Bartholin,
which are analogous to the Cowper's gland in the male, where AP is
excreted. The AP indicates sexual activity, but the gender of those
involved is not certain.
--- In forensic-science@yahoogroups.com, Donna Hansen <dhansen@...>
wrote:
>
> Would you be able to share the information or location about the false
positives with the RSID- semen test.
>
> From: forensic-science@yahoogroups.com
[mailto:forensic-science@yahoogroups.com] On Behalf Of johnsonethan95
> Sent: Friday, September 30, 2011 1:25 AM
> To: forensic-science@yahoogroups.com
> Subject: [forensic-science] Re: Wording of Serology Reports
>
>
>
> RSID test is no better. There is a fair amount of information on false
positives from RSID test. Seems like we have run out of options.
>
> --- In
forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.c\
om>, Donna Hansen dhansen@ wrote:
> >
> > I just wanted to say we were having the same issue with the semen
cassettes but we were getting false positives with our Seratec p30 test
cassettes and were going to switch to the ABAcard. We ended up switching
to a semen specific test called RSID-Semen; it tests for the presence of
Semenogelin which is only found in semen (as its documentation states
now just like p30 was specific back in the day). As for your conclusion
- we basically conclude the same way except we say "Semen was or was not
detected on Item ....". Where Semen was positive but no spermatozoa were
detected - we included that information on our report "Semen was
detected but no spermatozoa were observed". I cannot really address
option 4 but we were close (before we started using RSID-Semen) to using
an inconclusive result.
> >
> > Do you do a preliminary color test i.e. acid phosphatase - if you do
are those results taking into consideration as to how you conclude your
semen result?
> >
> > From:
forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.c\
om>
[mailto:forensic-science@yahoogroups.com<mailto:forensic-science%40yahoo\
groups.com>] On Behalf Of labgirl28
> > Sent: Wednesday, September 28, 2011 10:57 PM
> > To:
forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.c\
om>
> > Subject: [forensic-science] Wording of Serology Reports
> >
> >
> >
> > My laboratory is on the cusp of revamping our Serology SOP and the
way that we word some of our serology testing on our final reports. I
know that the "word of the day" when it comes to ISO, which is where
most of us are headed, is TRANSPARENCY. Nothing would make me happier
and more comfortable as a forensic scientist to be able to go to court,
clearly state what tests were used, and openly show/explain their
limitations. Anyone that has read about the North Carolina debaucle
understands that a scientist's report, despite their best intentions AND
following proper protocol, can be grossly misinterpreted without them
personally being present to explain it and in turn, ruin their career in
forensics.
> > Anyhow, several of my coworkers are facing some resistance by
administration when it comes to how we report out semen testing and what
"weight" we give to these tests in regard to probative value. Let me
also say that we were getting false (+)'s with ABAcard psa on known
semen-free samples. Their was some discussion about temperature, pH, and
viscosity issues that could cause these results. Due to these issues, we
switched to Seratec's product. I will also state that our DNA section
does tell the end of the story many times by stating whether foreign DNA
is present in our swabbings and cuttings which is a small comfort to us
serologists, but that sometimes, the mere reporting of semen being
present is all it takes for a jury to convict, even if DNA is not
obtained. I am trying to poll other forensic laboratories to see how you
guys report out the following testing so that I can attend our next
brainstorming meeting with some possible suggestions:
> > 1) Spermatozoa identified
> > 2) No Spermatozoa identified, (+) p30 result
> > 3) No Spermatozoa identified, (-) p30 result
> > 4) No Spermatozoa identified, p30 result(test line intensity is
lighter than internal standard of 4 ng/mL)
> >
> > For 1), we currently write "Semen was identified on.....".
> > For 2), we currently write "Semen was identified on.....".
> > For 3), we currently write "No semen was found on....".
> > For 4), we currently write "Tests for the presence of semen were
inconclusive.".
> >
> > Sadly, our current protocol dictates that if our test line is (+) or
less intense than the internal standard, we must repeat the test with
another p30 card of the same lot # (I don't see this as sound scientific
practice). If the second test is also (+), we follow 1) wording as
above. If the second test is (-), we are told to write "No semen was
found on..." (I don't agree with this.) I know that Seratec is very
sensitive. The manufacturer clearly shows examples of fainter lines
being still interpreted as (+) for p30. I also know that the test line,
results being based on a bell curve of concentration, may be fainter
because there's low quantities of p30 OR very high quantities,
approaching the high-dose hook effect level which would give you a false
(-).
> > Do any other laboratories interpret these faint lines as anything
other than (+)? Does your lab call this (+) for p30, a component of
semen OR (+) for semen?
> >
> > Do your reports give disclaimers about p30 being found in low levels
of other body fluids?
> >
> > Lastly, does your laboratory consider p30 testing to be
sensitive/specific enough to be called a confirmatory test for semen?
Ours has for years and doesn't want to even consider backing off on
report wording to view it as presumptive, which many of us feel is
imperative. There was some talk of describing it as "indicitive," but
that is what the poor soul in North Carolina used and we all know how
that turned out for him! We're all of the "worst-case scenario" mindset
and fear one day, major consequences could befall our laboratory or us
analysts though we are following SOP as set forth and attempting to
remain subordinate to our superiors.
> > I know I've rambled for a lengthy spell here, but we've got a burden
on our shoulders that needs resolution. Misinterpretation of data is not
an acceptable answer for me. I don't see anywhere on Seratec's website
where they consider any type of line in the Test area to be anything but
(+). That is the bottom line. My signature on a laboratory report means
something to me and I don't want it to lose its value.
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
> [Non-text portions of this message have been removed]
>
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