Creative Photography Entry Bone Marrow

I saw this creative photography site and thought, "why not enter?" I just finished taking pictures of bone marrow for a hematology class and I took this photo in an area of the slide that you couldn't look at for morphology because everything's all mooshed together. But it was a good place to get a feel for the diversity of cell types and the presence of fat. It also kind of looks like marble. This was taken on an Olympus microscope under 100X oil emersion lenses and given a little touch of yellow in photoshop for contrast.

Blood Banking 101 Part 1

The blood bank is probably the most mysterious place in the hospital. Most people have no idea what goes on there - you order blood, it appears, end of story. Of all the places in the hospital lab, the blood bank is the one with the fastest pace and the greatest drama. It's also the place many people refuse to work because small errors there can evolve into huge problems later on and the federal government has recently decided that it will no longer pay for the sequalea of such - a mixed blessing to be sure.



The other night we had a patient who had 5 perviously undetected alloantibodies - antibodies to blood groups she had been exposed to through transfusion. This is an incredibly difficulty person to transfuse because the chance of finding a unit of blood that lacks all the antigens she had antibodies to is about one in three hundred. When you only have 20 units of her type in your refrigerator, there's no way you're going to find something on-site. We have to send out to reference labs to get special prescreened blood for people like her.



There are a number of reasons people develop these antibodies - some are naturally occurring, some are acquired after transfusion and some develop after a pregnancy. Of the naturally occurring antibodies, there's really only one group that anyone cares about most of the time- the ones to the ABO group. The ABO antigens are carbohydrate antigens that we are exposed to and make antibodies to without previous transfusion. They are IgM antibodies with an expanded thermal range and react well at body temp. The rest of the naturally occurring antibodies are "cold reacting" - they react at room temp but not at 37C. This means that they are a nuciance to us in the blood bank because they will make patients hard to cross-match for transfusion (cross match reactions are done at room temp) but for the most part, the patient isn't going to die from an antibody that doesn't react at body temperature.



The antibodies that really cause problems are the warm reacting ones which are ususally acquired after exposure to someone else's blood. The most important of these are antibodies to the Rh group of antigens and antibodies to antigens in the Kell and Kidd group. You'll notice that the two most important groups (ABO and Rh) are the ones we type everyone for which is why they are on the label of the blood bag you get but it's certainly possible to be sensitized to C and E antigens in the Rh group or other random antigens.

Way You Can Tell You've Been Hanging Around A Pathologist

1. When someone tells you that a relative died, your first question is, "What'd they die of?"
2. You're watching a horror movie and someone says, "Wow! They got that splatter pattern just right."
3. You know random things like what the number one cause of amputation is in the U.S.
4. You can't talk about work without radically departing from the norm of polite dinner conversation
5. When you complain, they say, "it could be worse, you could be dead!"

This post about pregnancy screening tests, called the triple screen or quad screen, evoked some strong discussion. There seems to be widespread confusion about these tests.

First, it's important to consider what conditions they potentially detect.

1. Down syndrome or trisomy 21


2. Trisome 18


3. Neural tube defects
   

What is actually measured is three or four substances in the serum of the mother. These are:

1. alpha-fetoprotein, a protein made by immature livers which is also produced by certain types of liver cancer (this test is used by itsself as a tumor marker when cancer is suspected)


2. human chorionic gonadotropin - a substance made by the placenta which is also used as the marker in pregnancy tests


3. unconjugated estriol - also a placental product although low levels can be found in adults


4. inhibin A - inhibin A is made largely by the dominant follicle/corpus luteum in a woman. It inhibits the production of FSH in vitro and is produced in large amounts by the placenta and fetus.

There are several things to keep in mind about these tests. First, they are only predictors of risk. False positives far outnumber the true positives. Second, the only way to really know if the fetus has a trisomy is from a direct genetic test like amniocentesis or chorionic villus sampling. So when you get a positive, chances are still pretty good that nothing is wrong. Also, the tests can be totally negative and you can still have a child with the screened-for disease.

Discussion among parent's groups talk about what people would do if the test was positive. Would you abort or not? Is it important to have the test to make sufficient plans? But I think what never comes up is what happens if the test is false positive? If you abort and then find out there is no abnormality. What about those people who opt for amnio and then miscarry a "normal" baby? These tests have to be interpreted with caution and with a fuller understanding than the average 15 minute doctor visit can provide.

Additional information about this screening can be found at WebMD and at the American Pregnancy Association.

You Should Be in Pictures

AKA - Reason 523 why lab people will never be replaced by machines.

We had a hum-zinger of a case the other day. A CSF was sent down with so many WBCs and bacteria it almost seemed like pus. We took it to the pathologist immediately - if it was really CSF that patient was in for a seriously bad time (or he was dead).

The pathologist headed up to the unit where he was staying and stuck her head in the room. The patient was sitting in bed playing a videogame on the new system we just got installed. Since it was clearly impossible that someone with CSF full of bacteria would be calmly jumping Mario over turtles, she headed over to the nurse's station to ask some questions.

Yes, the patient did have a spinal tap not too long ago.
No, he hasn't improved dramatically in the last few minutes.
Yes we can find his doctor for you - hold on.

The doctor reported that the CT scan showed nothing and that he could pull the X-ray (Pathologist - "gosh that's a great idea") and sure enough between L2 and L3 there was an abscess that the radiologist had missed. The CT scan had stopped just short of the region that was infected.

Things started to happen. Neurosurgery was called. The patient had the spinal abscess drained and eventually recovered. The CLS involved got to go home knowing she had saved a guy's life because instead of just reporting the result (as a machine might have) or rejecting the sample she followed up and set into motion the chain of events that got this patient the treatment he needed.

We don't get to be heros very often - this was very cool.

Baby Bacteria

Baby microbiota has recently been analyzed anew in an article by Palmer et al. While this does not directly relate to the clinical lab per se, I thought it interesting from a clinical microbiology perspective. The study followed 14 babies (including one set of twins) from birth to one year, with samples taken monthly. Also, the mothers, fathers, and siblings were also sampled. In addition to stool samples, they swabbed the mother's vaginal tract and analyzed samples of their milk. There were several findings in the study that I thought were particularly interesting:

1. The microbial community of the gut was extremely varied between babies but converged on the adult "distribution" near the end of the first year, when the babies started on more solid food.



2. Bifidobacteria did not appear in most babies until several months after birth and were an insignificant part of the overall population of the gut. My favorite line in the study: "we suspect that the emphasis on Bifidobacteria in studies and reviews of the infant GI microbiota may be out of proportion to its prevalence, abundance, and relevance to health."



3. The only babies that had gut flora with significant similarity were the two (fraternal) twins. The researchers concluded that the environment is the source of the bacteria that colonize the gut and that children in different households have a gut flora that resembles their unique exposures / experiences.



4. Major changes occurred in the gut flora in short periods - almost like a succession of communities for no apparent reason (except in one case, when major changes occurred after a baby was given antibiotics)
   

This study was conducted using DNA microarrays that allow scientists to scan thousand (to millions) of DNA sequences in order to find those that exist in a sample. Ten years ago, this study could not have been done - both because the microarray technology was not sophisticated enough and because insufficient numbers of microbes had been sequenced to construct good phylogenetic trees that compared discovered sequences to those that were known. The paper's authors include such luminaries as David Relman (who discovered Bartonella hensleae, the causitive agent of most cases of cat scratch fever, from 16s ribosomal RNA long it was ever cultured - a first for microbiology) and Patrick Brown, the man who is credited with doing the most groundbreaking work with microarrays, using them to characterize yeast gene expression and differentiate between different human cancers (work which could make anatomic pathologists obsolete someday).

The tantalizing question we are left with is what caused the shifts in those baby's gut flora? Will they have long term effects on the adult flora (and does that even matter?) Do c-section babies have a different flora from those birthed vaginally? And finally, even if we knew the answers to the first three questions, would we be able to do anything with the information, or would it be wise to try? I left the research world a while ago but studies like these always get my "what if" juices flowing again.

Why Students Are Good For Us

I just worked with a new batch of students today. They were great! Fresh and interested, this class has a sense of humor and it shows. They were joking and talking with each other like they'd been friends for years. More importantly, they were excited about starting something new and excited to be training. There's a sort of contact high you get being around so much positive energy. I love working with them.

I've read other people talk about how different professions "eat their young" and we do too in the lab sometimes - although not as much as you might think. There's usually a period of hazing, especially in areas with a lot of structure. I think what we do is a little different than what nurses do - our hazing is less based on displaced aggression and more based in a total discomfort with change so complete it is, at times, pathological. The fact that most of us are over 50 doesn't help much.

I try to help the students as much as I can. I tell them to ask their trainers how their doing because most of us are too shy to give feedback, even when they're driving us nuts. I also encourage them to be little happy rays of sunshine. Working amongst perfectionists, we forget to talk about the 85% of things that are good and focus only on the depressing (and all consuming at times) 15% that is less than ideal. One of my favorite people to work with is a wonderful woman who sprinkles praise in her conversation like the sugar covered raisins in raisin bran. People like her are all the more noticeable for their rarity.

I've also seem some great changes in local labs as more new people have come in - the more experienced folks are kinder (in some cases) to the newbies and really try to recruit them so there's one more person to cover Christmas. And new people means more tolerance for change - a slow shift. I'm looking forward to seeing how things are altered over the next ten years because I think replacing half the staff with energetic newbies will make it a much more exciting and fun place to work. When they ask questions, we'll be forced to peer into the darker more cobwebby bits of our memories for the answers (or to discover just how much you can find out at labtests online.) The new crew also is increasingly international which should make the pot lucks exciting. Fun times ahead!