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Krasowski, Matthew D

0000-0003-0856-8402

Mayo Clinic

Department of Pathology, University of Iowa Health Care, Iowa City, IA, United States.

Citations 7

ADLM Guidance Document on Incorporating Gender Diversity in Pathology and Laboratory Medicine
Thomas, Tiffany, Winston‐McPherson, Gabrielle , Amarillo, Pérez, Berry, Alisha D. , Davidge‐Pitts, Caroline , Devaraj, Sridevi, Goldstein, Zil, Karon, Brad S. , Katzman, Brooke M. , Khalifa, Mahmoud A. , Stockley, Tracy L, Stoffel, Michelle , Davidge-Pitts, Caroline , Luu, Hung S , Nichols, James H , Stoffel, Michelle R , Greene, Dina , Krasowski, Matthew D , Amarillo, Ina, Devaraj, Sridevi , Goldstein, Zil , Luu, Hung S. , Nichols, James H. , Stockley, Tracy , Greene, Dina N. , Krasowski, Matthew D.

The Journal of Applied Laboratory Medicine | April 18, 2026 | Volume: 11 | Issue: 4 | Pages: 887-926

10.1093/jalm/jfag071 Get It

Abstract Background The first international clinical standards of care for the gender-diverse population were formulated in the late 1970s. In the last 15 years, multiple subspecialty societies within the United States have developed clinical care guidelines for those with gender dysphoria, including gender-affirming hormone therapy (GAHT) and surgical treatments. To date, there are no pathology- and laboratory medicine–specific recommendations in the United States for the gender-diverse population. Content This document outlines pathology- and laboratory medicine–specific recommendations for providing optimal care to the gender-diverse population, with a predominant focus on the adult population. The scope of this document focuses on the following 5 topics: (a) reference intervals and interpretation of laboratory tests impacted by use of GAHT (testosterone for transgender men; estradiol with or without antiandrogens for transgender women), focusing on those stably on GAHT for 6 months or longer; (b) transfusion medicine considerations for the gender-diverse patient population, (c) consideration of gender diversity in autopsy and death investigation, (d) interpretation of histology from tissues that are impacted by GAHT and surgical procedures; and (e) pathology and laboratory medicine informatics challenges and opportunities. Summary A relatively small group of laboratory tests is significantly impacted by GAHT. The histology of some tissues shows changes attributable to GAHT or to nonhormonal medical procedures. Autopsy and transfusion medicine practices for the gender-diverse population currently lack standardization, although this is evolving. The landscape of pathology informatics related to gender diversity is complicated by varying electronic health record and laboratory informatics systems functionality.
ADLM Guidance Document on Laboratory Testing for Drugs of Misuse to Support the Emergency Department
Snozek, Christine L H, Colby, Jennifer M. , Johnson-Davis, Kamisha L, Bruccoleri, Rebecca, Snozek, Christine L , Krasowski, Matthew D , Snozek, Christine L.H. , Krasowski, Matthew D. , Johnson‐Davis, Kamisha L. , Melanson, Stacy E.F.

The Journal of Applied Laboratory Medicine | October 16, 2025 | Volume: 11 | Issue: 1 | Pages: 155-180

10.1093/jalm/jfaf172 Get It

Abstract Toxicology testing for drugs associated with scenarios such as recreational use or substance use disorder can be performed in support of the emergency department (ED) for specific patient populations such as pediatrics and trauma. These compounds were historically referred to as drugs of abuse (DOA); although the word “abuse” is recognized as potentially stigmatizing, no replacement terminology for DOA has emerged in current guidelines. This document refers to these compounds as drugs or substances of misuse, and acknowledges the need for less-stigmatizing language that more fully encompasses the range of uses for these drugs. This literature-driven, consensus guidance document provides recommendations primarily targeted to US hospital-based laboratories performing urine drug testing (UDT) in support of the ED. Indications for ordering UDT and related testing in both pediatric and adult populations are summarized. Further, recommendations are made for testing that should be available at all facilities with rapid turnaround, and how to perform and report testing. The advantages and disadvantages of immunoassays and mass spectrometry, as well as common challenges, are reviewed. Indications for mass-spectrometry assays and more extensive testing (e.g., novel psychoactive substances) are also provided. Future directions for improvements in laboratory technology to improve the utility of this testing are outlined. All laboratories should collaborate with ED leadership, medical toxicologists and poison control centers to optimize and update test menus to reflect local drug use patterns, ensure test methodologies and results meet clinical needs, and educate clinical staff regarding assay limitations and accurate test interpretation.
Estradiol Concentrations for Adequate Gender-Affirming Feminizing Therapy: A Systematic Review
Winston‐McPherson, Gabrielle , Thomas, Tiffany, Cirrincione, Lauren R. , Katzman, Brooke M. , Rytz, Chantal L. , Goldstein, Zil , Greene, Dina N. , Winston-McPherson, Gabrielle N , Krasowski, Matthew D , Cirrincione, Lauren R , Goldstein, Zil , Greene, Dina , Krasowski, Matthew D. , Ahmed, Sofia Bano , Pierre, Christina C. , Miranda, Keila Turino

LGBT Health | June 24, 2025 | Volume: 12 | Issue: 7 | Pages: 477-489

10.1089/lgbt.2024.0407 Get It

Purpose: Guidelines recommend serum estradiol concentrations of 100–200 pg/mL for transgender women prescribed oral, subcutaneous, or transdermal estradiol with or without adjunct antiandrogen as gender-affirming feminizing hormone therapy (HT). The purpose of this systematic review was to evaluate if the guideline range of 100–200 pg/mL for estradiol concentration is associated with indicators of adequate gender-affirming feminizing HT, specifically feminizing sufficiency, insufficiency, testosterone suppression, or toxicity in transgender women. Methods: The Populations/Intervention/Comparator/Outcome model was applied to the study question, whereby the target population included transgender, gender-diverse, and nonbinary adults using gender-affirming feminizing HT by any route of administration, with or without adjunct antiandrogen use. The comparator was defined as estradiol concentrations within (100–200 pg/mL or 367–734 pM) versus outside (</>100–200 pg/mL) the guideline range; evaluated outcomes were listed by the same clinical guidelines that recommend using the 100–200 pg/mL range. Embase, MEDLINE, and Web of Science were queried over a 24-year time frame (January 1, 1999–April 20, 2023); the search was restricted to English. The extracted outcomes were categorized as indicators of therapeutic insufficiency, sufficiency, toxicity, or hormone concentration. Results: There were 49 studies that met the inclusion criteria, of which 9, 42, 25, and 5 studies included indicators of therapeutic insufficiency, sufficiency, toxicity, or hormone concentration, respectively. The search did not identify articles demonstrating that the 100–200 pg/mL guideline range provides optimal feminizing outcomes or reduces adverse events. Conclusions : Evidence does not support using the guideline range of 100–200 pg/mL to indicate sufficient feminization in transgender women using gender-affirming feminizing HT.
Nicotine and Tobacco Alkaloid Testing and Challenges: Lessons Learned From a College of American Pathologists Proficiency Testing Survey
Snozek, Christine L.H. , McMillin, Gwendolyn A. , Nwosu, Ann, Dizon, Annabel, Krasowski, Matthew D. , Krasowski, Matthew D

Archives of Pathology & Laboratory Medicine | October 12, 2022 | Volume: 147 | Issue: 6 | Pages: 634-642

10.5858/arpa.2022-0094-cp Get It

Context.— Consequences related to nicotine (NIC) use remain a major health concern, leading to demand for testing to detect NIC, metabolites such as cotinine (COT), and related tobacco alkaloids, including anabasine (ANAB). NIC-related testing is not standardized among laboratories, nor are there clinical or regulatory guidelines to inform decisions such as appropriate screening cutoffs or limits of quantitation. Objective.— To evaluate analytical performance and reporting practices of laboratories that perform NIC-related testing by reviewing participant responses to the Nicotine and Tobacco Alkaloid (NTA) Proficiency Testing Survey. Design.— NTA results were retrieved from 2017 (the first year of the survey) through 2020. Survey participants, methodologies, and results were evaluated for all analytes, and simulated grading was performed for COT. Additional data, including limits of quantitation, qualitative cutoffs, and reasons for testing, were reviewed. Results.— Participant growth was steady for qualitative COT testing. Participation was stable for NIC, ANAB, and quantitative COT testing. Overall, participants performed well on survey challenges. However, reporting thresholds were widely divergent, ranging from 10 to 3000 ng/mL and 0.5 to 300 ng/mL, respectively, for qualitative and quantitative COT testing. Screening cutoffs were as high as 100 ng/mL for ANAB and 1000 ng/mL for NIC. Conclusions.— Although participating laboratories performed well on the NTA Survey, the wide diversity of qualitative and quantitative reporting thresholds creates substantial risk for misinterpretation of results, and could lead to analytical concerns such as excessively high false-negative or false-positive rates. NIC-related testing would benefit from evidence-based guidelines to drive standardization of reporting.
Therapeutic Drug Monitoring of Second- and Third-Generation Antiepileptic Drugs
Krasowski, Matthew D., Long, Thomas A., Snozek, Christine L. H., Dizon, Annabel, Magnani, Barbarajean, Melanson, Stacy E. F., Melanson, Stacy E.F. , Krasowski, Matthew D. , Krasowski, Matthew D , Long, Thomas A., Snozek, Christine L. H., Dizon, Annabel, Magnani, Barbarajean

Archives of Pathology & Laboratory Medicine | March 15, 2021 | Volume: 145 | Issue: 12 | Pages: 1485-1491

10.5858/arpa.2020-0562-cp Get It

Context.— Therapeutic drug monitoring has traditionally been widely used for first-generation antiepileptic drugs (AEDs) such as carbamazepine and phenytoin. The last 2 decades have seen the introduction of second- and third-generation AEDs (eg, lamotrigine, levetiracetam, and topiramate) into clinical practice. Objective.— To use data from the College of American Pathologists Therapeutic Drug Monitoring, Extended Proficiency Testing Survey to determine the performance of assays used for therapeutic drug monitoring of newer AEDs, including comparison of enzyme immunoassay and chromatographic techniques. Design.— Six years of proficiency testing surveys were reviewed (2013–2018). Results.— Steady growth was seen in participant volumes for newer AEDs. The analytical performance of automated enzyme immunoassays for lamotrigine, levetiracetam, and topiramate was similar to that of chromatographic methods, consistent with published literature using patient samples for comparisons. The majority of participating laboratories now use enzyme immunoassays to measure levetiracetam. Conclusions.— Survey results reflect steadily growing interest in therapeutic drug monitoring of newer AEDs. The increasing availability of robust immunoassays for new AEDs should facilitate their clinical utility, especially for clinical laboratories that do not perform chromatographic assays for therapeutic drug monitoring.
Ethanol Biomarker Testing and Challenges
Snozek, Christine L.H. , Souers, Rhona J., Dizon, Annabel, Magnani, B, Krasowski, Matthew D. , Krasowski, Matthew D , Magnani, Barbarajean

Archives of Pathology & Laboratory Medicine | February 26, 2021 | Volume: 145 | Issue: 12 | Pages: 1492-1498

10.5858/arpa.2020-0699-cp Get It

Context.— Clinical and forensic testing for ethanol biomarkers, including ethyl glucuronide (EtG) and ethyl sulfate (EtS), is used to discern alcohol use from abstinence. These markers can be key in major decisions, including transplant eligibility or retaining licensure after alcohol misuse. Accuracy, precision, and recognition of the implications of reporting cutoffs are all essential for correct interpretation. Objective.— To evaluate trends in testing for EtG and EtS, including how laboratories perform testing and how comparable participant results are. Design.— The study examined the College of American Pathologists ethanol biomarker proficiency testing survey from 2013 to 2019. Trends in methodology, reporting cutoffs, and participant performance were evaluated for qualitative and quantitative EtG testing and for quantitative EtS testing. Results.— There was little consensus in reporting cutoffs, which ranged from 10 to 1000 ng/mL for EtG and 10 to 1500 ng/mL for EtS. Although median EtG and EtS compared well with target concentrations, individual participants' results varied widely. For quantitative enzyme immunoassay, accuracy and precision were best in EtG challenges less than 1500 ng/mL. For EtG or EtS by mass spectrometry, overall accuracy was good over a wide concentration range, but variability between participants was high. Approximately 10% (409 of 4059) of results were unacceptable, which for mass spectrometry corresponded to more than 35% above or below the group mean. Conclusions.— Although many participants performed well, there was insufficient consensus in reporting cutoffs, and a consistent fraction of laboratories failed to achieve survey standards. Guidelines for assay performance and reporting could greatly benefit laboratories and end users.
How Can Routine Clinical Laboratories Keep Up with the Opioid Crisis?
Snozek, Christine L.H. , Baskin, Leland B. , Boyd, Jessica M. , Kelly, Brian N. , Krasowski, Matthew D. , Sadrzadeh, S.M. Hossein, Tacker, Danyel H. , Krasowski, Matthew D

Clinical Chemistry | November 20, 2020 | Volume: 67 | Issue: 2 | Pages: 338-344

10.1093/clinchem/hvaa305 Get It