Acquired B Phenotype

Students learning about the ABO blood group system commonly get confused about two unique situations: The Acquired B phenotype and the Bombay phenotype.

These two entities are VERY different, but they are similar in this way: people are asked about both on exams all the time, but hardly anyone every actually SEES either one in real life! It is essential for students of blood banking to understand Acquired B clearly, as it remains a real possibility in everyday practice. I’ll cover Acquired B in this month’s blog, and next month I will discuss Bombay.

Routine ABO testing is performed in two distinct (but usually simultaneous) stages, known as “red cell grouping” (forward grouping or “front type”) and “serum grouping” (reverse grouping or “back type”). Here’s an example of how it works: If a person’s red blood cells (RBCs) react strongly with reagent anti-A but not anti-B, we would interpret their red cell grouping as blood group A. If there is no ABO discrepancy, that same person’s serum should have no reaction with reagent group A1 RBCs and strong reaction with reagent group B RBCs (demonstrating the expected presence of anti-B in the serum). Thus, the serum grouping interpretation would also be blood group A, and no ABO discrepancy would exist (see this illustrated in the figure below).

aboexample

ABO discrepancies occur any time the interpretations of a person’s red cell and serum grouping do not agree. ABO discrepancy takes on many forms, and acquired B is a great, if not terribly common, example.

Students learning about the ABO blood group system commonly get confused about two unique situations: The Acquired B phenotype and the Bombay phenotype.

Usually, Acquired B occurs when the RBCs from a blood group A patient come in contact with bacterial enzymes known as “deacetylases.” These enzymes, commonly carried by bacteria that live in the colon, catalyze the removal of the acetyl group from the residue that gives the A antigen its specificity, N-acetylgalactosamine (GalNAc). This modification leaves the A-specific sugar as galactosamine (N-acetylgalactosamine with the acetyl group removed = galactosamine). Recall that normally, the group B-specific sugar is galactose.

acqb

As a result of this modification, anti-B in both human group A serum and especially certain monoclonal reagents will weakly agglutinate the group A RBCs carrying the acquired B antigen. This means that the patient’s RBCs may have a weakly positive reaction with anti-B in serum grouping tests instead of the expected negative (see image below). The serum grouping for these patients is no different from that expected for a group A individual (negative with group A reagent RBCs, strong positive with group B RBCs).

acqbabotesting

So, what does this actually mean? How do these patients actually get transfused? This is where the recognition of the entity in a transfusion service or reference laboratory is essential. Several simple strategies can be employed to prove that this patient is really NOT group AB. First, I always advise people to check the patient history! The rare cases of acquired B that are still seen will often be associated with colorectal malignancy, gastrointestinal obstruction, or gram-negative sepsis (where those bacteria can contact the RBCs). Second, adding the patient’s own serum to his RBCs (autoincubation) reveals no incompatibility. In other words, this patient’s own very strong anti-B does not recognize the acquired B antigen (which is really just a partially modified group A antigen) as being an actual group B antigen. We already know that this patient has anti-B in his serum from his serum grouping results (see above), but the patient’s own anti-B completely ignores the acquired B antigen on his RBCs (even though human anti-B from other people will react). Third, the technologist can use a different form of monoclonal anti-B in the patient’s red cell grouping test. Certain clones are known to react with acquired B, while others are not (normally specified in the package insert), and choosing a different clone (often easier in reference lab settings) will render the forward grouping consistent with that of a group A person. Also, incubating the Acquired B RBCs with acetic anhydride will lead to “re-acetylation” of the modified A antigen and loss of the B-like activity. Finally, acidifying the reaction mixture of the patient’s RBCs with human anti-B (non-self) can eliminate the incompatibility with that source of anti-B.

In the end, Acquired B is a serologic problem that is fairly easy to recognize, especially on examinations (I always tell my students that when they see a problem that starts with words like, “A 73 year old male with colon cancer…”, check the answer for Acquired B!). In real life, experienced blood bankers can diagnose and confirm Acquired B fairly easily in the rare times that it is seen. These patients can receive group A blood without a problem, and the ABO discrepancy will disappear as the infection or other situation causing causing contact with bacterial enzymes clears. Thanks for your time and attention. See you next month when I will discuss the Bombay Phenotype!

 

Chaffin

-Joe Chaffin, MD, is the new Vice President and Chief Medical Officer for LifeStream, a Southern California blood center headquartered in San Bernardino, CA. He has a long history of innovative educational efforts and is most widely known as the founder and chief author of “The Blood Bank Guy” website (www.bbguy.org).

Resident Concerns, Part 1: Boards Prep

So I’m writing this blog while taking a break from the 2014 CAP Annual Meeting (I hate high heels and my feet are killing me from standing by my poster). As a resident, one of the most enjoyable parts of every conference that I attend is meeting and speaking with other residents. It’s even better if the conference planners organize specific events, networking receptions, or a resident lounge where residents can meet and socialize with each other and other trainees and pathologists. The CAP Annual Meeting is always good in terms of providing residents such outlets.

The best part for me is hearing stories of other resident experiences different than my own in addition to making new friends and colleagues. So my next couple blog posts will be about some of the topics that came up as the most important from the residents I spoke with: boards preparation, the fellowship application process, and networking/engagement opportunities for residents.

So, in terms of the boards, two themes seemed to emerge. First, many felt that the Resident-In-Service-Exam (RISE) does not correlate well with what we need to know to prepare for boards. For instance, this example was given to me: a decent percentage of questions on the RISE focused on forensics while most had heard that the boards have very questions dealing with forensics. My opinion on this topic is that it depends on what your expectations are concerning the RISE. If you are hoping that the breakdown of the RISE is a simulation of the boards in mini-form, then you might be disappointed. But if you like to advocate change for a different focus for the RISE, then I’d encourage you to bring your concerns to the RISE committee at rise@ascp.org and provide a cogent argument for your views…my motto is always, “you never know, the worse that they can say is no, so it’s better to try.” It certainly is not irrational to want our in-service exam to reflect what we need to know most for the boards and for real-world practice so let the RISE committee know.

Secondly, the topic came up of what is tested on the boards in terms of breakdown. I also wondered the same thing since I need to prepare chemistry and molecular pathology podcasts for for ASCP’s Lab Medicine Podcast Series and had no clue what would be high-yield topics that I could focus on (if you have a specific topic or test in these areas that you’d like a podcast on, please feel free to let email me and I’ll try my best).

So, I asked someone I know at the American Board of Pathology (ABP) about this issue. She directed me to the APCP Exam Blueprints which outlines the overall breakdown of number of questions in specific topic areas on the most recent board exam. I’ve also been told that they will post category codes for the various exams (ie – something like a “table of contents”) to the ABP website soon.

Looking at the blueprints, I have a better idea of some of the board topic areas that I will need to concentrate on (although there is nothing listed for molecular pathology but maybe there isn’t that much yet on the boards or it’s included within other AP/CP areas like soft tissue or hematology). And apparently, this is much more info than has been previously provided. But again, if you want a more detailed breakdown or other information that you can’t find on the ABP website, I also encourage you to communicate your concerns to Dr. Rebecca Johnson, the CEO of the ABP. Remember, positive change only occurs if there is a stimulus for change, and that stimulus can be you! As attendings, we need to be pro-active in questioning and changing the status quo for the better, so why not start practicing or acquiring those skills while a resident.

 

Chung

-Betty Chung, DO, MPH, MA is a third year resident physician at Rutgers – Robert Wood Johnson University Hospital in New Brunswick, NJ.

 

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.

 

 

What’s Your Number?

When I ask “what is your number,” I mean “what is the percentage of time you spend on the bench versus time in the office doing administrative work.” In my laboratory we currently have a chemistry supervisor on extended leave so myself and the hematology supervisor are 90/10 bench/office. I know what you’re thinking, how do you do the administrative portion while working the bench that much? The answer is simply, we can’t. Unless I work 60 hour work weeks there is no humanly possible way to be able to work on the bench and get done what I need to in the office. Prioritizing the administrative duties and taking advantage of slow days on the bench is the number one reason why I am somewhat successful at getting things done.

The biggest challenge I face is competency. One of CLIA’s six competency guidelines is physically watching each technologist/technician perform each test that is on our test menu. So let me break this down. I have 15 employees that need to complete competencies. We perform gel testing in blood bank as well as LISS, PEG, and Pre-warm screens in tube if necessary. Let’s round all of those tests to 45 minutes. 15 employees times 4 different methods is 60, times the 45 minutes is 2700 minutes, or 45 hours. Now don’t forget that I am in the hospital setting which is 24/7 so I have to be available for second and third shift if I want to make sure those employees are competent. So for simplicity sake I’m going to round those hours up to 48 which makes six 8 hour days of competency. If I get two office days a month, competency will take me four months to accomplish and that isn’t counting my other duties. This is also assumes uninterrupted time which we all know happens once a millennia. These are just four tests as well; we perform many others such as antigen testing, long crossmatching, etc. When looking at this it can be overwhelming but there are ways to accomplish the impossible without killing yourself.

One way to help yourself out is to look at the CLIA definitions of who can be a technical supervisor for competency testing. Chances are you have more than one employee who qualifies and as long as you sign them off as competent they can sign off other employees. This can drastically cut down the amount of time you need to spend individually with each employee. Another way is to have the employee’s videotape themselves performing the tests while explaining out loud what they are doing. This not only confirms their competency but you can watch back the tape at your leisure as well as show inspectors if they ask how you satisfy the observation portion of the competency. I now ask you in the comment section below write down your numbers and let me know what your biggest challenges are and some possible solutions. We can help each other out, and share in the continuous struggle. So, what’s your number?

 

Herasuta

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.

Generation Gap from a Resident’s POV

I was talking with my attending and fellow this week and was struck by the generation gap in terms of how we were/are trained. When my attending was in residency, he had to handle over 100+ CP calls in a week – he even keeps one of his call sheets to back up his stories. In some ways, we are spoiled because we can just say that there is an APP to do many of the calculations he had to do then and so we’re not even paged on these types of calls. These days, I may average 10+ CP calls/week at the same institution where he trained at. He also said that they didn’t have PAs back then and it wasn’t unusual to gross until close to midnight…and the grossing resident also covered all frozen sections at the same time, too. His is not the first attending story that I’ve heard like this. Obviously, this was before we had work hour reform. But I wonder what we’ve lost in training since his time?

I’ve often heard residents complain that we have too many service duties and that they feel that service duties supersede our education. Most of the time these complaints revolve around not having enough time to read and too much “scutwork” including grossing routine specimens. I’m no expert by any means but I feel that for me, I’ve learned more when I’ve had to do things as opposed to reading textbooks. And by doing things, I mean performing those duties that are required of my attending as close as possible to the real experience. And yes, that does include lots of reading, not just textbooks but also journal articles and other resources, but is not limited mainly to reading.

Gone are the days where I could skip (or attend) my medical school classes and watch a video of the lecture and read the textbook and do well on exams. The more important difference is that now the consequences of my actions can more directly harm patients so it’s vitally important to gain “attending skills” as well and as soon as I can. And even after graduation, I know that it will still take a few years before I am comfortable in my clinical competency. I know that I’ll be more stressed and OCD about details because it will be my name at the end of the report that is responsible for patient care decisions and also liable for medico-legal action. But I want to be as prepared as possible when that time comes.

Residency is the time when we should transition from passive learning (ie – learning mostly by reading textbooks) to active “on the job” learning. Sure, if no one at your program wants to teach you, then you may be stuck with textbooks and online resources. But I’ll take a bet that even at the most “malignant” programs, there is always at least one golden mentor (including non-attendings) who wants to teach. And remember, that during fellowship, your attendings will expect that you have most of these skills in your portfolio and that you have good time management skills. No one expects that we have knowledge of everything (even our attendings don’t have that), but they will expect that we know how to approach that situation if we find ourselves unsure.

Anyway, that’s not my most important point. I find that complaining just wastes my energy that can be directed to a more useful endeavor. Yes, if I feel something is truly unjust, I will be one of the first to say something. But I realize that the patient is the center of my training and not me, their needs supersede mine, and yes, there will always be scut but it depends on how I approach it what I get out of it. Plus, I realize that compared to other specialties, I didn’t have an intern year and don’t have to do overnights, so I’m thankful that my residency experience is not as bad as it could be.

A generation gap exists where our attendings can’t understand why we complain and where we don’t feel our attendings understand us. But I think that there is a middle ground. I don’t think that we should go back to unregulated work hours where we are dangerously fatigued and never get to see our family and friends. But I also don’t believe that residency training is there to spoon-feed me. It is the time for me to spread my wings (with supervision, of course) and learn how I’d navigate my clinical duties as a future independent attending.

For those going into surgical pathology, you may still end up working at a hospital where you may need to gross or at least, look at specimens or teach how to gross. The end of residency doesn’t necessarily mean the end of grossing (or insert you least favorite aspect of residency here). A friend was telling me that he overheard attendings at a networking reception complaining about a new hire they had who didn’t know how to gross. If that was at a private practice, I would expect that after a short time allowed for remediation, that if that new hire didn’t improve, s/he would be fired. There may be more leniency at an academic or VA institution, but I also believe that if a better replacement could be found, that person would still be fired.

So residency is the time to make sure we gain competency in skills like grossing, lab management, billing, CLIA regulations…even if these are usually the things that we find to be boring. Sign-out is not even half of what will be required of us when we are full-fledged attendings, especially if you want to work in private practice, which is where most of us end up since the compensation is greater.

Getting involved in leadership positions, whether at your hospital, state society, or within a national advocacy organization in my experience opens doors to many practical opportunities as well. For instance, I’ll be going with my hospital’s CAP lab accreditation inspection team this month to help inspect the hematology section of a lab in another state. Because my department chair knows I have an interest in hematopathology and because I performed well on my first CP rotation here, I was given this great opportunity. I’m now certified as a CAP inspector and will have a better idea of lab management issues after this experience. Due to my involvement as the junior member on CAP’s Council on Education, I’ve also been given the opportunity to serve as the ACCME/AMA compliance monitor at a joint CME activity of CAP and a state pathology society in the near future. I see this as active learning and a step toward gaining the competencies that I will need.

Right now, we are buffered from much more than we realize. Probably as a fellow, we will understand the end game better, just how much our attendings’ days are filled with more than just sign-out. I suggest reading the article, “Adequacy of Pathology Resident Training for Employment: A Survey Report from the Future of Pathology Task Group” that outlines specific competencies that employers wanted and that residents did not possess adequate competencies in. It goes on to state that 50% of employers felt that new graduates that they hired needed more support and guidance than was required 10 years ago. So what can we do now during training to ensure that we are not those new graduates who are perceived as needing “more” supervision at our first job?

 

Chung

-Betty Chung, DO, MPH, MA is a third year resident physician at Rutgers – Robert Wood Johnson University Hospital in New Brunswick, NJ.

CDC Update on the Ebola Outbreak

Yesterday Dr. Tom Frieden, Director of the Centers for Disease Control in Atlanta, briefed the media about the current Ebola outbreak in Africa and called for an immediate global response to the outbreak. “There’s nothing mysterious about what we need to do,” says Frieden. “The only real question is whether we’ll do it fast enough.”

Read the full transcript on the CDC website.

Read Maryn McKenna’s astute summary on the Superbug blog.

Laboratory Testing in A High-Containment Facility

The team at Emory that cared for the patients infected with the Ebola Virus have published a paper on Lab Medicine about laboratory testing within a high-containment facility. You can read the entire paper on the Lab Medicine website.