A Primer on HIV, Hepatitis, and Clinicals: A Bronx Tale

Hello again everyone! Last time on Lablogatory, I discussed the importance of patient advocacy and how it was especially poignant around the recent holiday season. We all have families, and sometimes those families and our medical professions intersect. Since then, I hope you’re all having a good start to the new year!

For me, the new year means a new start in medical school with clinical clerkships in New York City. Building off the theme I started last year, I hope to continue a message of patient advocacy through a laboratorian’s lens as I learn and navigate the clinical side of our field. My first such rotation is in a clinic serving a population with very significant statistics, both from the standpoint of laboratory data and epidemiology: HIV, hepatitis, and chronic infectious disease. As such, let me use this as a primer and explore what that really means for the patients in that community.

Now it’s no surprise that laboratory professionals like ourselves are deeply involved with public health efforts aimed at mitigating chronic/infectious diseases through screening, collaborating, and advancing technology. Last year I was fortunate enough to be part of the 2017 ASCP Annual Meeting in Chicago. Participating in sessions, and roundtable discussions, I was also able to listen to US Global AIDS Coordinator, Deborah L. Birx, MD had to say regarding ASCP’s global contributions to HIV/AIDS research and public health efforts. She spoke about resource limited laboratories and how ASCP has been an active and longstanding partner to the President’s Emergency Plan for AIDS Relief (PEPFAR), a global health initiative to address HIV/AIDS.

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Image 1. My wife Kathryn C. Booth, RN, MSN, CNL, and I, take part in a roundtable discussion at ASCP Chicago 2017. From Critical Values: 2017;11(1):34-39. doi:10.1093/crival/vax040
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Image 2. US Global AIDS Coordinator Deborah Birx, MD, delivers the scientific general session at ASCP 2017 in Chicago. From Critical Values: 2017;11(1):34-39. doi:10.1093/crival/vax040

The relationship between laboratory data and epidemiology is evident, as results from screening and routine testing demonstrates both snapshots of evolving health statistics as well as progress in public health initiatives like PEPFAR. ASCP’s global initiatives reach all the way to Africa as those resource-limited laboratories gain support from telecommunications and shared materials. From rapid HIV tests with Western Blots, to Zika seroprevalence research, laboratory data and public health are dependent on each other. So how does this manifest in a place like New York, specifically the Bronx where my clinical rotations are located?

First, let me illustrate a snap shot of the scene in this New York borough. Something that demonstrates important data are a region’s social determinants of health—something I have found in my research and experience to be invaluable pieces of information when trying to address health concerns and influence outcomes with particular patient populations.

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Figure 1. A clear layout of New York’s Boroughs. I currently live in Manhattan and go to clinical sites in the Bronx for my clerkship rotations. (Alamy stock photo. Photo credit: http://www.alamy.com/stock-photo-new-york-city-5-boroughs-map-96927034.html)

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Figures 2-5. 2015 NYC Rates of Persons Living with Diagnosed HIV compared against variable social determinants of health including poverty, high school education, median income, and income inequality. Accessed through AIDSVu.org interactive map, visit it here: https://tinyurl.com/y8u9op8v

It’s clear to see here that the Bronx area has the most significant epidemiologic presence of active and new HIV cases. Parallel to this, the data demonstrates that the social determinants of health illustrated in Figures 2-5 are clearly correlative. More so, in the most recent report by the New York City Department of Health and Mental Hygiene (DOHMH) and the office of HIV Epidemiology and Field Services Program (HEFSP), data collected since 1981 from reported clinical encounters, viral loads, CD4 counts, and HIV genotypes reveal significant social health statistics. According to their 2016 NYC HIV/AIDS Annual Surveillance Statistics, the Bronx remains plighted with high numbers for HIV. It would appear as well, that regardless of HIV status, an overwhelming majority of the population (>71%) live in very high poverty—defined as >30% of the federal poverty line. According to data from Community Board 6, the local representation for the Bronx and specifically the zip code around my clinical site, the median household income is $24,537. A majority of this population is comprised of minorities as well, >40% Black and >40% Latino. The data differs slightly between men and women (including transgendered men and transgendered women) with regard to transmission risk. For men the highest risk factor continues to be sexual transmission between homosexual men, or men who have sex with men (MSM). For women, the risk stratifies to a high majority of heterosexual transmission (>70%). Read the full 2016 NYC DOHMH report here: https://tinyurl.com/ycf82xld. According to AIDSVu.org nearly 3,000 people out of 100,000 residing in the Bronx are living with active diagnosis of HIV/AIDS. The same source reports that between 2011 and 2015, the number of new cases approaches 200 annually.

Another valuable function of the AIDSVu.org website is their HepVu.org companion site which provides incidence and infographic data about Hepatitis infections. The Hepatitis B and C Annual Report for 2014 published by the NYC DOHMH in 2016 also provides information about this chronic condition and how it affects the population. The maps below demonstrate that chronic Hepatitis is a serious and prevalent problem, and at a slight majority directly affects patients proportional to age.

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Figures 6-8. Maps from the DOHMH NYC Hepatitis B and C Annual Report for 2014 published in 2016. (Source: https://www1.nyc.gov/assets/doh/downloads/pdf/cd/hepatitis-b-and-c-annual-report.pdf)
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Figure 9. Mortality rates of HepB, HepC, and HIV in New York City at large. Note the decrease in HIV and slight increase in HepC. (Source: https://www1.nyc.gov/assets/doh/downloads/pdf/cd/hepatitis-b-and-c-annual-report.pdf)

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Figures 10-11. Maps that demonstrate that even though New York State has a lower-than-average HepC prevalence rate, it has a relatively higher rate of mortality. Source: https://hepvu.org/resources/

But what does all this data mean? First and foremost it means progress. Progress for our patient populations because we’re busy tracking and keeping ahead of health statistics as they happen, and progress in our innovative ways to test earlier, screen better, and use the data wisely. None of this would be possible without the lab. From every hepatitis viral load, antigen immunoassay, and serology, lab data becomes translated to health data. And, all the while, clinical encounters with real patients experiencing real chronic illnesses are reported into epidemiologic data. Together we use those two sets of data to improve patient outcomes—I talked about that a lot with Zika in Sint Maarten.

I am honored to be at that bridge between the lab and the patient. Translating data back and forth from bedside to primary source is something that brings me a real sense of purpose. As part of this clinical rotation I will have to be involved in patient education, delivering presentations and conducting follow-up with those in the community who these public health messages are targeted to. So, instead of boring you some more with facts about lab science, testing/screening opportunities, and a promising future for those with chronic illness, I’ll go ahead and get a presentation ready for them!

Talk to you soon with some more in-depth clinical case-based blogging! Thanks for reading!

 

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Constantine E. Kanakis MSc, MLS (ASCP)CM graduated from Loyola University Chicago with a BS in Molecular Biology and Bioethics and then Rush University with an MS in Medical Laboratory Science. He is currently a medical student at the American University of the Caribbean and actively involved with local public health.

New Year. New Skills.

I do not recall if it was an email or if I saw it on the ASCP website, but the byline caught my attention: New Year. New Skills. My mind quickly started racing. January marks a fresh beginning, the time to make new resolutions, the time to feel the excitement of new possibilities. 

The Issue

We are more than halfway through the month and I have yet to identify the skill I would next like to acquire. So many questions! So much to learn, so little time! How do you choose what to focus on? Where do you start? What can you manage? Is there anyone who can help or teach you? And if you are like me, you might also ask yourself, “Why do I always pile more on my plate?” Maybe this is the year you choose to learn to say no? Nah. So what’s it going to be?

The Solution

Since our lives are all different and there are millions of possible distinct scenarios, I will share what I decided to do. First, I evaluated my work-life balance and determined if I wanted to acquire a skill that would benefit my work (career and ambition) or lifestyle (health, pleasure, leisure, family) (1). I also took into consideration how much more I could fit onto my already overflowing plate.

I decided to work on something that would help me with both work and lifestyle (because who doesn’t like to maximize their return on investment?). I chose something I do not like to do, something that scares me, something I have difficulty with, something I avoid like the plague, but most importantly it’s something that I wish I could do better; a skill that I envy: having difficult conversations.

Communication is a vital component of our lives. We all communicate, but how many of us have mastered the skill of communicating? Also, there are many aspects of communication (2). Poor communication can make or break a situation or relationship. Being able to communicate well is a great skill to possess (3). Reference two provides a long list of skills that I highly recommend you also take a look at (https://www.thebalance.com/communication-skills-list-2063737). I went down the list and individually assessed which skills I feel that I do well with and which ones I do not (2). This little exercise served as a reality check as to where I stand in regard with my aptitude to communicate. I invite you to do the same. You may be surprised at what you find!

The Importance of Good Communication

As a laboratory director, many facets of my job depend on my ability to communicate well. I must communicate with clinicians, technologists, administrators, other coworkers, vendors, students, etc. Not only do I communicate with a variety of groups of people, in a multitude of different platforms (individually, small groups and meetings, or large groups; such as national conferences), but it is also important that my written, verbal, and non-verbal communication skills are clear and easily understood.

As laboratory professionals, one very important aspect of our job is to communicate critical results. It is essential that we not only relay the data, but it is equally important for us to communicate it well so that the clinician completely understands the information so that they can properly care for the patient. Moreover, we must not forget the golden rule: garbage in, garbage out. What I mean by this is that good communication should begin in the pre-analytical phase. We want the clinician to provide the laboratory with the best possible specimen so that in turn, we can provide them with the most accurate result. So how do we ensure that we obtain the best possible specimen? We communicate.

The laboratory communicates our needs to the provider in order to properly do our job. For example, we provide detailed information on how to properly collect specimens, which container type to use, how to handle the specimen, how much (volume) specimen to submit, which temperature to submit the specimen, etc. Properly communicating these details is essential.

The Difficult Conversation

As laboratory professionals, we are just one part of a larger healthcare team. If you stop to think about it, we all have to participate in difficult conversations as part of our jobs. Doctors have to tell patients that they are going to die, laboratory professionals have to tell clinicians we lost their specimen, executive administrators have to tell downstream leadership that the budget has been cut again, managers and supervisors have to tell employees they are being written up or worse. Being able to successfully have a difficult conversation would serve us all well. As such, most institutions provide classes or webinars to help employees develop this skill.

The definition of difficult is: not easily or readily done; requiring much labor, skill, or planning to be performed successfully; hard (4). Carrying out a difficult conversation with grace is an extraordinary skill that encompasses a variety of communication attributes. Regardless of the scenario, the communicator must be clear, articulate, and courteous. However, depending on the scenario, being concise, confident, strategic, diplomatic, convincing, empathetic, motivating, open-minded, and/or quick thinking may also be useful skills to possess during a difficult conversation. Other valuable skills are conflict management, being able to explain, and/or listening. 

The Conclusion

For many, the New Year marks the time to set new goals, to accept new challenges, and welcome new beginnings. Why not use this opportunity to learn a new skill? The good news is that no matter what your new skill will be, it will also benefit your health. In order to acquire a new ability, you must work to actively learn to become proficient in that ability; therefore learning a new skill will also benefit your brain function. There are many studies that demonstrate that active learning keeps the mind sharp (5). Challenging your mind improves brain function and active learning slows cognitive decline (6). If you want to be brave, then don’t only choose a skill that will be fun or helpful, but choose to learn something that also challenges you to face one of your fears. For me, I hope to learn how to master the art of having difficult conversations….successfully. In the words of Marie Curie, “Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less.”

Happy learning! Happy New Year!

 

The References

  1. Work-life Balance. https://en.wikipedia.org/wiki/Work–life_balance. Accessed January 16, 2018.
  2. The balance. List of Communication Skills for Resumes. https://www.thebalance.com/communication-skills-list-2063737. Accessed January 16, 2018.
  3. The balance. Communication Skills for Workplace Success. https://www.thebalance.com/communication-skills-list-2063779. Accessed January, 16, 2018.
  4. com. Difficult. http://www.dictionary.com/browse/difficult. Accessed January 16, 2018.
  5. Stenger, M. 2013. New Study Shows How Active Learning Improve Cognitive Function. https://www.opencolleges.edu.au/informed/other/new-study-highlights-activities-to-improve-cognitive-function-6008/. Accessed January 17, 2018.
  6. Park, D.C., Bischof, G.N. 2013. The aging mind: neuroplasticity in response to cognitive training. Dialogues Clin Neurosci. 15(1): 109-119. PMC23576894. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3622463/. Accessed January 17, 2018.

 

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-Raquel Martinez, PhD, D(ABMM), was named an ASCP 40 Under Forty TOP FIVE honoree for 2017. She is one of two System Directors of Clinical and Molecular Microbiology at Geisinger Health System in Danville, Pennsylvania. Her research interests focus on infectious disease diagnostics, specifically rapid molecular technologies for the detection of bloodstream and respiratory virus infections, and antimicrobial resistance, with the overall goal to improve patient outcomes.

Safety Motivation

If you search for top motivational movie speeches, you will see things that might work in real life. The President’s speech from Independence Day (1996), for example, might influence you to never be oppressed by alien tyranny. Freedom will be your rally cry after listening to William Wallace in Braveheart (1995), or Maximus from Gladiator (2000) can speak to your heart about teamwork. Unfortunately, such speeches do to tend to maintain motivation for great lengths of time. Also, none of them will translate to a motivational discussion about safety with your lab staff.

Over many years I have watched what motivates people to do the right thing or take the safe actions in the laboratory, and that motivation varies. Different groups of people are persuaded by different forces, and understanding that can help you move your lab safety culture in the direction you desire. You may not agree with or even like some of the influencers, but learning them can help you be more effective in achieving overall safety compliance.

They say money is a motivator for people in all kinds of circumstances, and that’s true for lab safety as well, although not in the way you might believe (while some businesses may pay a bonus for fewer safety incidents, that is not typical in the lab setting). Lab staff who are concerned about finances are more open to following some lab safety practices if they realize the cost savings. Obviously, lab injuries and exposures cost the department both monetarily and with staff absences. Following proper regulations can reduce costly citations and fines that can be levied by organizations like OSHA, the EPA, or CMS. Some lab team members want funds available for new equipment or more staff. Use that to encourage them to follow proper safety procedures. Make sure staff properly segregates waste in the lab, for example, since doing things like placing paper into a sharps container costs the department extra money. Hospital and lab leadership also respond well to financial motivation. If you need something fixed or replaced because it is unsafe, always explain the financial consequences to the facility if the fix is not approved.

Knowledge can also be a powerful safety stimulator for some staff. Understanding the consequences of poor safety behaviors will discourage some, and education about those consequences needs to be given regularly. Let’s look at waste disposal again- those who are concerned about the environment should know that tossing clean items into a biohazard container could increase the need for biohazard landfills in the area- something we should avoid. Talking about the follow up testing and unpleasant effects of prophylaxis following an exposure from an unknown source can be very eye-opening. It may spur staff to be more careful when potential exposure situations arise.

You might not like to hear that punishment can be a motivator for correct behaviors, but for some staff members it is. Sometimes, explaining that a written corrective counseling or even termination will occur if safety practices are not followed will keep laboratorians working carefully and correctly. No one wants to “threaten” people to do the right things, but there will be those who are only motivated by not wanting to “get in trouble.” Knowing who those employees are can be important to guiding your leadership approach when working with them.

Lastly, some lab staff are inspired to act safely because the environment is designed to make doing so easy. PPE is readily available- lab coats of all sizes are accessible, gloves are out and not in a drawer, and face protection is mounted conveniently. There are hooks for lab coats near exit doors and hand washing sinks so that staff can properly doff and exit. Cleaning supplies and spill kits are readily available and instructions to use them are posted and up to date. Warning signs are there for staff and for visitors not used to the dangers in the department. I know that many labs are older, and the physical layout is not always conducive to making safety easy, but there are always steps that can be taken in order to make safety easier to achieve. You may need to step back and look at your environment with fresh eyes in order to envision what can be done to make improvements.

Think about what incentives are important to you when it comes to lab safety. Is it simply self-preservation? That’s good, but for many who are complacent about safety, their motivation may be different. Finding their reasons to be safe is a worthwhile task. It helps you understand better who your staff is as a people, and it will help you gain expertise for providing the stimuli they need to continue to work safely today and every day.

 

Scungio 1

Dan Scungio, MT(ASCP), SLS, CQA (ASQ) has over 25 years experience as a certified medical technologist. Today he is the Laboratory Safety Officer for Sentara Healthcare, a system of seven hospitals and over 20 laboratories and draw sites in the Tidewater area of Virginia. He is also known as Dan the Lab Safety Man, a lab safety consultant, educator, and trainer.

Which Potassium Do You Believe?

A patient presented to the Emergency Department at the St. Paul’s Hospital. Initial blood was collected by phlebotomy staff (one poke) at 6:55 am in the morning and the specimen was received in the lab at 7:11 am.

Venous blood gases: Potassium  7.3 mmol/L
Plasma Lytes: Potassium  3.3 mmol/L

Emergency phoned the lab about these discrepant potassium results. What is going on?! The venous gas specimen was centrifuged and appeared hemolysed (3+), while the plasma sample had no evidence of hemolysis.

The phlebotomist indicated there was no problem with the collection. Repeat testing was initiated an hour later.

Venous blood gases: Potassium  6.4 mmol/L
Plasma Lytes: Potassium  3.6 mmol/L

The venous gas specimen was centrifuged and appeared hemolysed (3+).

Because the venous gas specimens were transported on ice and the other tubes of blood collected were sent at room temperature, the biochemist discussed the possibility of a red cell cold agglutinin with the ER physicians. The ER physicians requested evaluation for a cold agglutinin (the EDTA tube collected for early hematology was used for this analysis). Lab staff performed the screen and it was 4+ for cold agglutinin.  ER physicians were advised to believe the lower potassium results and to avoid sending further specimens on ice for this patient.

 

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-Dr. Andrew Lyon, PhD, FCACB, DABCC is a clinical chemist and clinical toxicologist. He is the current past-president of the Canadian Society of Clinical Chemists. He is currently Division Head of Clinical Biochemistry of the Saskatoon Health Region and teaches general pathology residents as a clinical associate professor of Pathology and Laboratory Medicine at the University of Saskatchewan.

Lymphocytosis Can Be Anything

Case History

A 63 year old patient presented with a high white cell count of 108 K/uL and thrombocytopenia of 110 K/uL.

Peripheral smear examination revealed marked lymphocytosis with presence of numerous small to medium sized lymphoid cells with round to oval nuclei, clumped nuclear chromatin and variable amount of cytoplasm, some with cytoplasmic projections. As the features were consistent with a lymphoproliferative disorder peripheral blood was sent for flow cytometry.

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Based on the morphology the differential diagnosis included B-cell lymphoproliferative disorders such as marginal zone lymphoma, hairy cell leukemia/variant, or less likely chronic lymphocytic leukemia and/or mantle cell lymphoma.

Flow cytometry revealed presence of clonal B-cells expressing CD19, CD20, Cd11c, CD103 and FMC-7. The cells were negative for CD5, CD10, and CD25.

The phenotype together with the morphology and CBC findings were diagnostic of hairy cell leukemia variant.

Discussion

Hairy cell leukemia variant ( HCL-v) is a B-cell lymphoproliferative disorder that resembles classic hairy cell leukemia but exhibits variant cytological and hematological features such as leukocytosis and also shows variant immunophenotype including absence of CD25, CD123 and/or annexin A1.

HCL-v is about one tenth as common as HCL (hairy cell leukemia) with an annual incidence of approximately 0.03 cases per 100,000 population. There is slight male preponderance. Patients with HCL-v typically present with leukocytosis with an average WBC of 30 K/ul and /or thrombocytopenia.

The 5 year survival rate is around 50-60%. Most patients require therapy which can range from splenectomy to combination chemotherapy with Rituximab.

 

Reference

  1. WHO classification of Tumors of Haematopoietic and Lymphoid Tissues; IARC 2017

 

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-Neerja Vajpayee, MD, is the director of Clinical Pathology at Oneida Health Center in Oneida, New York and is actively involved in signing out surgical pathology and cytology cases in a community setting. Previously, she was on the faculty at SUNY Upstate for several years ( 2002-2016) where she was involved in diagnostic work and medical student/resident teaching.

Safety in the Pre-analytic Phase

The courier suddenly became sleepy in the middle of his daily driving route. It was cold outside and he had all of the windows in the vehicle closed. He also had filled his cooler with four pounds of dry ice, and it was sitting in his back seat.

There was no education at the hospital for specimen collection staff regarding proper label placement on collection tubes. Since the CBC analyzer would not accept tubes with labels that were too long, the lab techs kept a razor blade handy to slice off extra label paper. It wasn’t long before someone cut their finger.

The phlebotomist completed the outpatient collection, but the large elderly patient was unable to stand up from the chair without assistance. The phlebotomist bent at the waist and attempted to lift the patient to standing. The back muscle pull that followed kept the phlebotomist out of work for two weeks.

Every laboratory professional understands the value of quality in the pre-analytic phase of laboratory testing. If you have ever worked where phlebotomy has been decentralized and is no longer overseen by the laboratory, you may have experienced the many pitfalls due to inadequate specimen collection techniques. Laboratory professional by nature want to provide good diagnostic results, and compromised specimens hinder that resolve. Sometimes, however, the aspects of safety that are important during the pre-analytic phase of lab testing get overlooked.

Needle safety and ergonomics should be considered during blood collection from patients. Using a needle with an attached safety device and activating it as soon as possible are important steps in needle stick prevention. Make sure there is a sharps disposal container near the point of collection or wherever needles are used so that the potential hazard can be eliminated quickly. When collecting blood, be sure to raise the bed height (or the arm height if in a chair) so that excessive bending is avoided. Use a chair or a task stool to sit on while performing the collection to maintain a better posture throughout the procedure. Never attempt to lift patients by yourself, always ask for help. Thousands of back injuries occur every year in healthcare due to avoidable patient lifting errors.

For many laboratories, couriers are a vital part of the pre-analytic process. They bring specimens from clients and other labs, and their safety should be considered as well. Teaching dry ice safety is vital if it is used, and both couriers and lab staff need to be taught how to handle it appropriately. Dry ice sublimates (or changes to gas from a solid state), so it should never be placed into a sealed container, or the building pressure from expansion will cause the container to explode. Couriers should never place more than one pound of dry ice inside a vehicle, and the windows should be opened when transporting it to create good ventilation. The gas created from dry ice quickly reduces the oxygen content in the air, and the elevated Carbon Dioxide levels can quickly cause unconsciousness or even death. Never place dry ice leftovers in the sink for disposal. While it might be fun to run water on it to see movie special effects, the cold temperatures can burst sink pipes and even make the entire sink fall out of place.

If specimens for analysis arrive in the testing area, and they frequently aren’t ready for analysis- for instance the labels aren’t placed properly- go to the source of the error to make corrections. If inappropriate labeling is a constant problem, staff will create work-arounds to get the work done, and some of these work-arounds may not be safe. Poorly-labeled samples may prompt a lab tech to remove gloves in order to adjust the sticky labels, and that should never occur. The use of sharp blades may be another work-around, and staff injuries can occur. Be sure to explain to specimen collection staff the importance of proper labeling. Turnaround times are delayed, but staff safety is also a concern.

Lab Quality and Safety are often related, and rarely is it more so than during the pre-analytical phase of testing. Proper collection, labeling, and processing are all vital in order to provide high quality lab results, and that is the crux of what laboratorians wish to do. The same can be said for laboratory safety: that pre-analytical process can’t be done well without proper safety considerations. Safety events here will create staff injury, turnaround time delays, and potential errors with test results. Make sure staff understand the impact of good quality as well as safety in the pre-analytical phase.

 

Scungio 1

Dan Scungio, MT(ASCP), SLS, CQA (ASQ) has over 25 years experience as a certified medical technologist. Today he is the Laboratory Safety Officer for Sentara Healthcare, a system of seven hospitals and over 20 laboratories and draw sites in the Tidewater area of Virginia. He is also known as Dan the Lab Safety Man, a lab safety consultant, educator, and trainer.

Pitfalls of Prolactin Biochemistry Assay

Laboratories occasionally get questions from clinicians about prolactin results, mainly to either rule out high-dose hook effect or assess interference from macroprolactin. In most laboratories, sandwich immunoassay is used to measure prolactin concentration and it is widely known that older generations of prolactin assays suffer from hook effect and interference from macroprolactin. In the presence of extremely high concentration of prolactin, antibodies can be saturated, resulting in falsely low results, which is known as high-dose hook effect. Multiple cases have been reported in patients with giant prolactinomas, that their prolactin results were measured as normal or moderately elevated. In order to rule out high-dose hook effect, clinicians normally request laboratories to perform appropriate dilutions for prolactin in patients with large pituitary tumors. Newer generation of prolactin assays have better performance in this aspect, and most assays nowadays have no hook effect up to concentrations of 10,000 ng/mL, claimed by manufactures.

Another pitfall of prolactin assay is the interference from macroprolactin. Macroprolactin is a complex of prolactin bound to immunoglobulin, and thought to be biologically inactive. In the presence of elevated macroprolactin, patient is asymptomatic. However, macroprolactin can be picked up by prolactin immunoassays to some extent, and results in misdiagnosis as hyperprolactinemia. Reports showed that 15-20% of cases with hyperprolactinemia was due to elevated macroprolactin. Therefore, macroprolactinemia should be considered while evaluating hyperprolactinemia cases in the absence of symptoms or pituitary imaging evidence. Laboratories could easily perform dilution study to test if interference exists. To confirm the presence of macroprolactin, polyethylene glycol (PEG) 6000 can be used to precipitate macroprolactin followed by prolactin measurement in the supernatant. The presence of macroprolactin is suggested when the pull-down percentage is greater than 40-50%. This test is offered by many reference laboratories.

These two pitfalls of prolactin biochemistry assays should always be kept in mind by laboratorians, to provide better guidance to clinicians’ concern and workups on prolactin related cases.   

 

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-Xin Yi, PhD, DABCC, FACB, is a board-certified clinical chemist, currently serving as the Co-director of Clinical Chemistry at Houston Methodist Hospital in Houston, TX and an Assistant Professor of Clinical Pathology and Laboratory Medicine at Weill Cornell Medical College.