generalist – Page 32

Name That Cytogenetic Abnormality

A 36-year-old male presents with recurrent epistaxis and fatigue of several days’ duration. Physical examination reveals numerous ecchymoses scattered over his limbs and trunk. A CBC shows the following:

Hgb 9.2 g/dL (normal = 13.5 – 17.5 g/dL)
WBC 31×10⁹/L (normal = 4.5 – 11 x 10⁹/L)
Platelet count 23 x 10⁹/L (normal = 150 – 450 x 10⁹/L)

Review of the blood smear shows numerous hypergranulated immature myeloid cells. Rare cells like the cell below are also present.

What cytogenetic abnormality is most likely present in the abnormal cells?

inv(16)
t(8;21)
t(14;18)
t(15;17)
t(11;14)

The answer is D, t(15;17). This is a case of acute promyelocytic leukemia (or AML-M3 in the old FAB classification). The key to the diagnosis is the cell in the image above, which is an immature myeloid cell containing innumerable Auer rods. This cell is called a faggot cell because the Auer rods resemble a bundle of sticks (or faggot). Faggot cells are specific for acute promyelocytic leukemia; they are not seen in any other hematologic malignancy.

Other clues to the diagnosis which are not entirely specific for acute promyelocytic leukemia include the anemia and thrombocytopenia (which point towards bone marrow failure), and the leukocytosis (which presumably is comprised mostly of the hypergranular myeloid cells noted on the blood smear).

Acute promyelocytic leukemia (APL) is a type of acute leukemia in which the predominant cell type is the promyelocyte. The malignant promyelocytes in APL have a distinctive appearance which is different from that of normal promyelocytes. In most cases, the malignant promyelocytes in APL contain innumerable small azurophilic granules – but in rare cases, the promyelocytes are hypogranular.

The characteristic morphologic finding in APL is the faggot cell, as shown above. When you see faggot cells, you can make the diagnosis of APL based on morphology alone, without waiting for molecular or cytogenetic studies (which will show the characteristic t(15;17) of APL – but which take some time to perform).

Making an immediate, morphologic diagnosis is critical in cases of APL, because patients with APL cannot be given routine acute myeloid leukemia chemotherapeutic agents. The granules in the malignant promyelocytes contain substances which quickly activate the coagulation system. Traditional chemotherapeutic agents cause cell lysis and release of the procoagulant substances, which puts the patient at high risk for disseminated intravascular coagulation (DIC).

Patients with APL are given a drug called all-trans retinoic acid (ATRA) that overcomes the maturation block caused by the translocation between chromosomes 15 and 17. Following ATRA therapy, the malignant promyelocytes mature into segmented neutrophils, and the risk of DIC diminishes.

The other cytogenetic translocations in this question are seen in different disorders: inv(16) is seen in some cases of acute myelomonocytic leukemia (AML-M4); t(8;21) is seen in some cases of acute myeloblastic leukemia with maturation (AML-M2); t(14;18) is seen in follicular lymphoma; and t(11;14) is seen in mantle cell lymphoma.

-Kristine Krafts, MD, is an Assistant Professor of Pathology at the University of Minnesota School of Medicine and School of Dentistry and the founder of the educational website Pathology Student.

Poll Friday

Internationally Safe

With the serious and concerning news about international contagious disease, it’s always appropriate to remind ourselves of safety, both personal and protective. What laboratory professional has not donned the gown, the mask, the gloves…in an effort to protect ourselves, and also protect the patients we serve? We all have…but we all have also occasionally been cavalier about it.

In these times of viruses and antibiotic-resistant strains of microbes—and who knows what iterations of the above are in the “evolutionary muck” of the future—we stand in the cautionary shadow of the devastation they can cause. The invention of the microscope only served to give us a view of our un-seeable enemies, and they are countless.

I travel extensively, internationally and within the USA, and the risks of contagion are all around. It helps to keep yourself personally prepared by encouraging a robust immune system, eating/sleeping and hydrating well, and staying as healthy as is possible—but as we all know that is not always enough. It will also serve us well, as laboratory professionals, to both practice and teach personal protection in compromised situations. When at work, it’s obvious…but when in someone else’s lab, or hospital, or clinic, or even railway station, we must be diligent and alert to the unseen dangers of contagious disease contamination. Laboratory scientists are trained to treat every single action, specimen, and encounter as if it were a threat to health and safety, and yet…do we?

Life is short, disease is inevitable, and safety precautions are a must…but also a choice. Choose wisely, and don’t compromise! If your hospital/laboratory/healthcare system is following PPE and international safety regulatory compliance, good for you and those around you. We are the most knowledgeable infectious control specialists on the planet, and we have the obligation to lead the way in international and personal safety.

And as I mentioned in my last blog, let’s roll up our lab coat sleeves—and put those gloves and masks on…we have a lot of work to do!

–Beverly Sumwalt, MA, DLM, CLS, MT(ASCP) is an ASCP Global Outreach Volunteer Consultant.

Dilutions: How Are You Doing Yours?

If you ask someone to dilute a sample in half, pretty much everyone will do it the same way – add an equal volume of sample to an equal volume of diluent, whether that’s 1 mL to 1 mL or 100 µL to 100 µL. But if you ask people to do a 1 to 2 dilution, you may be surprised to get different results. That’s because I’ve found that the convention for writing dilutions is taught differently at different Medical Laboratory Science (MLS) schools.

A 1 to 2 dilution should be written as ½. It means to dilute something in half. But many times it will be written as 1:2. These two forms are actually not equal, despite the fact that they are used interchangeably in the laboratory. One is a dilution and the other is a ratio. In the scientific literature, if you see “1:2”, it means to add 1part to 2 parts. That will be 1 mL added to 2 mL, for a total of 3 mL, or a 1/3 dilution.

Unfortunately, this problem is prevalent in the laboratory. I’ve seen 1 to 10 dilutions written both as 1/10 and 1:10. It’s very important to know how the technologists in the lab are performing that 1 to 10 dilution. Are they doing a true 1/10 (1 mL sample plus 9 mL diluent) or are they actually doing a 1 to 11 dilution (1 mL sample plus 10 mL diluent)? Your patient results may be different depending on who does the dilution!

Coming into this field from a scientific background rather than an MLS background, I prefer the convention of writing a dilution as 1 over something, ½, 1/10, rather than as a ratio, 1:2, 1:10. However, perhaps the majority of medical laboratory scientists are taught the ratio. Either convention works fine as long as it is clear to everyone in the lab what dilution they are actually performing and being asked to perform. You might want to just check your own MLS and see how they do their dilutions.

-Patti Jones PhD, DABCC, FACB, is the Clinical Director of the Chemistry and Metabolic Disease Laboratories at Children’s Medical Center in Dallas, TX and a Professor of Pathology at University of Texas Southwestern Medical Center in Dallas.

Management and Administration Housekeeping Items

A few items relevant to your interests have crossed the editor’s desk over the past few days.

1. As we mentioned several months ago, laboratories need to provide lab results to patients (or their representative) when requested to do so. The Privacy Rule amendments went into effect on October 6, 2014. Is your lab compliant? Read the regulations to be sure.

2. The Draft Guidance for the FDA regulation of LDTs has been published. You can read them here and here. The FDA will accept comments about the draft for the next 110 days.

Confirmed Case of Ebola Diagnosed in the United States

CNN is reporting that a patient in Dallas, Texas is the first person diagnosed with Ebola Virus in the United States.

According to the CDC, the patient traveled to the United States from Liberia on 9/19-9/20. The patient exhibited symptoms on 9/24, sought care on 9/26, and was admitted to the hospital on 9/28. Today, the CDC received and tested samples from the patient and confirmed the presence of the Ebola Virus by PCR methodologies.

The CDC and the Dallas County Health and Human Services will conduct contact interviews to determine if the patient may have had contact with anyone while infectious. If any contacts are identified, they will be quarantined and monitored for 21 days (the longest known incubation period for the virus).

CDC director Tom Frieden, MD, MPH says, “I have no doubt in my mind that we will stop it here.”

Be that as it may, it doesn’t hurt to be prepared. Lab professionals and pathologists should be familiar with the CDC’s Ebola information page.

Making Solutions

It often seems to me that the art (or science) of making solutions is becoming a lost one. In this current day and age when most of our solutions come in a pre-made form and only require mixing, or at most, thawing and mixing, I believe we’re losing the ability to make solutions ourselves.

This thought came to me when I overheard a comment in a hallway about a shortage of physiological saline. It was back-ordered and we’d be in dire straits soon if we didn’t get any in. And I wondered: if we have solid sodium chloride in the laboratory and we have water, how can we have a shortage of physiological saline? And physiological saline is incredibly easy because you don’t even need to know the molecular weight of sodium chloride. If you want 0.9% physiological saline, that 0.9 grams of NaCl in 100 ml of water.

The same is true for any other easily made-up solution. We’re so used to having them pre-made for us, that we’re forgetting everything we learned in school about how to make solutions. Of course, being able to make solutions from scratch does presuppose that the lab still has chemicals, a balance and a pure water source. My lab does, but that’s because we run a lot of laboratory developed tests (LDT). Most laboratories may no longer keep chemicals, and even if they do, using a home-made reagent turns your assay into a LDT. Plus so many pre-made reagents have proprietary formulas that making them up from scratch is not possible. But for simple reagents like physiological saline, that perhaps is being used to perform dilutions or wash cells, I find it kind of sad that we rely on “store bought” reagents so much that we never consider making them ourselves. In that respect, I guess I’m something of a lab dinosaur.

Don’t get me wrong. I’m totally in favor of making our lab lives as easy as possible and pre-made solutions are one of the wonderful things that do that for us. In addition, if you buy pre-made reagents, you remove one variable that can affect results – was the reagent made up correctly, using the correct chemicals. On the other hand, I believe it’s also a good idea to know how to make up a solution if you should need to do so.

It’s a little comforting to know that this loss of ability may not be confined to the lab. I heard a pharmacist talk about a shortage of total parenteral nutrition (TPN) solution, which I suspect at one time every pharmacist knew how to make up from scratch.

Pandora’s Box

Archived in the ever-rich and exotic mythologies of the Greeks is the story of Pandora’s Box. It was actually a “jar”—which is strangely close to a “test tube” in my opinion. Pandora was given a wedding gift, a beautiful jar, with instructions not to open it under any circumstances. Curiosity killed the cat, so to speak, and she finally couldn’t resist. When she opened it, all the evil contained in the jar escaped and spread over the earth. She tried to close it but too late—the contents had already escaped. Only one thing remained in the jar at the very bottom—the Spirit of Hope.

I’m not sure the World Health Organization would agree with me, but “Pandemic” is very close to “Pandora.” In a world where international travel is commonplace the spread of contagious disease is a major concern. Rats on ships carrying plague may be a thing of the past, but viral-loaded passengers on an international flight happen every hour of every day. Think of all the headlines in the past decade that have highlighted international health risk issues. It seems that Pandora has unleashed a few additional mutated “evils,” and I doubt we’re through with all her mischief.

As laboratory professionals, we are essential to solving the public health issues confronting our world today. Rapid diagnosis, evidence-based research, viral load monitoring, susceptibility and pharmacological validation, managing toxicity—familiar territory for us, and just think of how much relies on our expertise? We are called on daily to be the platform and framework for “pandemic control” measures. Sitting in our clean, efficient, well-lit, safe and busy laboratories throughout our country it’s easy to forget there are bacterial and viral war zones not far from our shores…all it takes is a small rat on a creaky ship (or a young child on a red-eye international flight) to initiate a modern day plague world-wide.

Next time you hear “pandemic”, remember Pandora. Wash your hands, put on a mask, and peer inside that jar of hers and shake out some Spirit of Hope. Sprinkle it liberally around our laboratories and colleagues, and let’s roll up our lab coat sleeves—we have a lot of work to do!

–Beverly Sumwalt, MA, DLM, CLS, MT(ASCP) is an ASCP Global Outreach Volunteer Consultant.

Perfection

When I was in school I learned a lot about science and the laboratory science body of knowledge. The one thing that was emphasized over and over was accuracy and precision. It wasn’t until I secured my first position and started training did I realize just how important those two words were. Not only are we counted on for our accuracy, we are counted on for the repeated accuracy of everything we report to physicians. I have heard some statistics reported that up to 80% of physician decisions on courses of treatment are based on lab results. I really do not get caught up in that number because if you think about it every single value we report is going into a patient’s clinical picture and can affect a decision on a treatment one way or another. So the question always comes up, how do we deal with errors? This question is multifaceted and as a supervisor/administrator we are responsible for much more than just the correction of the error.

I wrote this in my 5 year progress report article but I think it deserves repeating. Everyone makes mistakes, but, it is how you recover and learn from your mistake that is most important. Everyone has had that sinking feeling in their stomach when they learned they have either reported out an incorrect result or have mislabeled a specimen. As a laboratory professional it is our biggest fear and each and every day we sit down at the bench and are expected to be absolutely perfect. Zero errors are a standard that not even the most efficient manufacturers know is possible yet we are expected to perform on this level each and every day. Errors happen to everyone, and when they do it is what happens afterwards that is key to inhibiting that error to occur again. Especially with newer technologists it is important to teach them so that they are able to recover and not make the mistakes again.

The first thing I do when an error is discovered is address it with the technologist. Ask them, “do you remember this sample or this patient? Do you remember what you were doing at the time this error happened?” One thing to watch is how much the technologist can remember. If they cannot remember too many details, were they trying to do too much at once? If they mislabeled did they have a pile of tube and labels while also trying to result specimens? With mislabels I found it helpful for myself to read the name in my head as I was labeling the tube. That way if what I was reading in my head did not match the label underneath I would stop to look. If it is a procedural error why did the technologist deviate from the actual process? Did they learn a shortcut but that shortcut actually increases the chances of error? Going over this with the technologist also will help them with their problem solving skills. Especially with new technologists building problem solving skills is vital to the success or failure of a young technologist. We know humans are not perfect, but when you work in an industry that accepts nothing less, each error made is amplified but also that much more important.

–Matthew Herasuta, MBA, MLS(ASCP)CM is a medical laboratory scientist who works as a generalist and serves as the Blood Bank and General Supervisor for the regional Euclid Hospital in Cleveland, OH.

Enterovirus D68

Over the past few weeks, hospitals around the country have seen a sharp uptick in cases of respiratory distress in children. The majority of patients test positive for Enterovirus D68, and most seem to have a history of asthma.

Only select laboratories test for this strain of enterovirus. If a suspected case comes to your facility, contact the CDC or your local health department for information about specimen collection and shipping.