Seeing the “40th Anniversary” cover of MLO
in October reminded us that with the first issue in 1969, Chuck had
already been working as a phlebotomist for two years. The lab was a
different world then. In most labs not only were eating, drinking, and
allowed while processing specimens, but if you did not dine there, you
probably went hungry. Forget using purifying bleach that left counter
surfaces dull; some labs used furniture or metal polish. Many lab techs
got their intro to the lab as phlebotomists, glassware washers, or media
makers. Yes, lab techs did their own phlebotomy and collected samples
for blood cultures and blood gases, performed bleeding times and
clotting times at the bedside, along with collecting blood from babies
for sweat chloride tests. In some hospitals, lab techs also performed
X-rays and assisted with cardiac catheterizations.
Lab technology was easily as much an art as a
science. We made their own bacteriology media, and odor was a
significant part of bacterial identification. In many labs, manual cell
counting for WBC, RBC, and platelets in blood was the rule rather than
the exception. Coagulation testing meant tilt-tube. Mouth pipetting was
the norm; only with WBC/RBC pipettes would tubing and a mouthpiece be
used. Many techs have tales about getting a mouthful of urine, serum,
spinal fluid, or reagent. How did we survive? The mystery is that most
of us did.
Lab techs often made their own chemistry controls
from pooled “normal” and “abnormal” sera, establishing values by running
aliquots for as many tests as appropriate. Most chemistry analyzers required
controls to be run every 10 patient samples, so a lot of controls got used.
Three items that, today, are taken for granted were
hard-fought for by lab-tech pioneers — many hospitals just did not think
that certain items were cost-effective or even necessary: 1) gloves (seldom
used unless the lab tech had a known hepatitis patient); 2) needle
boxes, especially in patient rooms (needles were recapped and later cut or
ground up to dispose of them); and 3) antihepatitis vaccinations (unless the
lab professionals wanted to pay for those themselves).
The lab was, and is, a wondrous place to work. We
have witnessed wonderful and exciting advancements during these past four
decades. The new generation of laboratorians will find this work as
challenging and rewarding as we did — and a whole lot safer.
MBA, MT(ASCP), CLDir(NCA);
and Barbara Millstein, MT-CLS(NCA), MedLabSupv(TN)
Do you know about shiga-toxin assays?
As a recently retired hospital-lab microbiology
supervisor [30+ years' to the bone yard], my concerns center around droves
of “baby boomers” following my footsteps out the door, while
well-educated-but-inexperienced techs begin filling these vacancies. This
column is dedicated to providing answers and suggesting solutions to a
variety of lab problems — and other things that just plain tick me off. What
impact will this have on patients and providers? I discovered firsthand how
diverse and inconsistent culturing and reporting practices are from one
institution to another when our lab began participating in College of
American Pathologists' site inspections.
Shiga-toxin assays: Assays for the
detection of shiga-toxin-producing Escherichiae coli have been around
for several years, yet many microbiology labs have not incorporated this
test into their routine stool-culture batteries. Amazingly, it has taken a
long time to get labs to even culture for the most common of the shiga-toxin
producers, E coli O157:H7.
Enterohemorrhagic Escherichiae coli (EHEC)
produce two potent cytotoxins called shiga-like toxins (SLT). These
cytotoxins are produced not only by E coli O157:H7 but also by other
serotypes. Studies have shown that an EIA (enzyme-linked immunoassay) for
EHEC detects approximately 40% more EHEC O157:H7 than does conventional
culture and also is able to detect 20% more shiga-toxin-producing E coli
that are non-O157:H7. I believe it.
In my lab, we gathered our own in-house data to
decide for ourselves the value of the shiga-toxin assay. We sent all
specimens positive by the shiga-toxin assay to our state health department
for confirmation and serotyping. Only 50% were confirmed as E coli
O157:H7. The other half were non-O157:H7 serotypes or non-typeable strains
of shiga-toxin-producing E coli. This was a no-brainer.
Consider the repercussions of missing a shiga-toxin-producing
E coli, in this age of antibiotic overuse. Providers are too quick to
start an antibiotic regimen on patients with acute gastrointestinal illness
before lab results are available. Treating a patient infected with a shiga-toxin-producing
E coli with antibiotics can literally shut down the kidneys! Renal
failure is life threatening, especially in the very young.
Want to hear some really interesting excuses for not
incorporating the shiga-toxin assay into the stool-culture battery? “How do
we bill for this?” My answer: Look in your codebooks; it is there.
“Why do we not see this organism in our lab?” you ask. “How do you know if
you do not do the test?”This test should be an integral part
of the stool-culture battery, not an orderable test. Whether this test
should be done should not be left up to the provider. It should replace
specific plating media and latex serotyping kits for E coli O157:H7.
To emphasize the importance of detecting and reporting shiga-toxin-producing
strains of E coli, we always add a comment to a positive result:
Stool specimen positive for shiga toxins:
Antimicrobial agents should not be used to treat shiga-toxin-producing E
coli. There is no evidence that the use of antimicrobial agents will
change the course of disease or is beneficial in any way. Moreover,
antibiotic therapy may result in the release of more toxins from the
bacteria and contribute to hemolytic uremic syndrome. Antimicrobial therapy
does not accelerate recovery.
Gannon, MT(AMT) HEW
the “Nancy Grace” for labs