Zebra-like bodies in COVID-19: is phospholipidosis evidence of hydroxychloroquine induced acute kidney injury?

COVID-19 (from SARS-CoV-2) is the cause of an ongoing pandemic, with an increasing number of cases and significant mortality worldwide. Clinical trials and extensive studies are being conducted on a large scale for a better understanding of the pathophysiology of this disease and its effect on different organs. Several experimental treatment protocols have been introduced, in which hydroxychloroquine (HCQ) was one of the first drugs used. While patients can develop many side effects of HCQ, studies have documented a rare association of long-term HCQ treatment with zebra-like bodies in the ultrastructural examination of kidney biopsies, a finding typically seen in Fabry's disease, as well as in association with chronic HCQ use, among other drugs. We present a similar finding in the postmortem examination of a male in his early seventies with COVID-19 infection, who received five days of HCQ treatment before stopping the medication due to cardiac and renal toxicity.

Utility of CD123 immunohistochemistry in differentiating lupus erythematosus from cutaneous T cell lymphoma.

AIMS: Histopathological overlap between lupus erythematosus and certain types of cutaneous T cell lymphoma (CTCL) is well documented. CD123+ plasmacytoid dendritic cells (PDCs) are typically increased in lupus erythematosus, but have not been well studied in CTCL. We aimed to compare CD123 immunostaining and histopathological features in these conditions. METHODS AND RESULTS: Skin biopsies of cutaneous lupus erythematosus (CLE, n = 18), lupus erythematosus panniculitis (LEP, n = 17), mycosis fungoides (MF, n = 25) and subcutaneous panniculitis-like T cell lymphoma (SPTCL, n = 9) were retrospectively reviewed and immunostained with CD123. Percentage, distribution and clustering of CD123+ cells were compared between CLE and MF and between LEP and SPTCL using χ2 and two-tailed t-tests. A higher percentage of CD123+ cells was observed in CLE than MF (P < 0.01), more frequently comprising ≥20% of the entire infiltrate (P < 0.01) and forming clusters (P < 0.01). Similarly, LEP showed a higher percentage of CD123+ cells than SPTCL (P = 0.01), more frequently comprising ≥20% of the infiltrate (P = 0.04) and forming clusters (P = 0.01). Basal vacuolar change or dyskeratosis was observed in all CLE cases and in 48% cases of MF cases (P = 0.05). Plasma cells were readily identified in 76% cases of LEP but in none of the SPTCL cases (P = 0.01). Adipocyte rimming by lymphocytes, hyaline fat necrosis and fibrinoid/grungy necrosis did not significantly differ between LEP and SPTCL. Dermal mucin also failed to distinguish between groups. CONCLUSIONS: CD123 immunostaining is helpful in differentiating CLE from MF and LEP from SPTCL, but should be interpreted in conjunction with clinicopathological features and other ancillary studies to ensure accurate diagnosis.

Superficial papular neuroma: Case series of a new entity.

BACKGROUND: Dermal neural lesions arise in various circumstances and may be difficult to classify. METHODS: We describe the clinical, histopathologic and immunophenotypic features of a series of terminally differentiated neural lesions not described previously, to our knowledge. RESULTS: Four cases from men aged 58 to 66 years were included. Some lesions reportedly bled, but no inciting trauma or prior biopsies were reported. None recurred after biopsy, with follow-up ranging from 19 to 113 months. All lesions were papular, with vertically oriented S100-positive spindled cells and nerve fibers in the papillary dermis. Slight epidermal hyperplasia, dilated superficial thin-walled vessels and minimal to mild inflammation were seen in each. Fibers were uniformly fine in 3 cases, with slightly thicker central fibers in the fourth. Three had parakeratotic scale. None were associated with dermal fibrosis or adnexal proliferation. Neurofilament stained axons in each. EMA was negative in all cases. CD34, melan-A and HMB45 were negative when performed. CONCLUSIONS: We report a small series of benign neural lesions and propose the name "superficial papular neuroma" for this distinct entity. Awareness is important to understand the clinical significance of these lesions and avoid misinterpretation that could lead to overtreatment, unnecessary work-up and increased cost.

Expression of the p40 isoform of p63 has high specificity for cutaneous sarcomatoid squamous cell carcinoma.

Cutaneous spindle cell malignancies such as sarcomatoid squamous cell carcinoma (SCC), leiomyosarcoma, desmoplastic melanoma (DM) and atypical fibroxanthoma (AFX) may be morphologically indistinguishable, yet accurate diagnosis is important for appropriate clinical management. The distinction among these entities relies on immunohistochemical evaluation for epidermal, muscle or melanocytic differentiation. Epidermal differentiation markers include cytokeratins and p63. p63 is expressed as two distinct isoforms, ΔNp63 (p40) and TAp63. p40 positivity is highly specific for pulmonary SCC and head and neck sarcomatoid SCC. We examined the utility of p40 vs. p63 immunostaining in the differentiation of a variety of cutaneous spindle cell malignancies, including sarcomatoid SCC (n = 27), AFX (n = 34) and DM (n = 10). p40 was less sensitive than p63 for detecting sarcomatoid SCC (56% and 81%, respectively). p63 and p40 were comparably specific for sarcomatoid SCC relative to AFX, with only rare weak staining of tumor cells for p63 and/or p40 in a minority of AFX cases, including one case with approximately 10% of cells staining weakly for p40. All cases of DM were negative for p40 and p63. Our results support continued use of p63 for diagnosis of cutaneous sarcomatoid SCC because of greater sensitivity relative to p40.

A Reassessment of the Impact and Significance of Social Media to Pathology.

CONTEXT.­: Social media (SM) use in pathology and medicine today is widespread, receives active advocacy, and is said to bring a host of benefits. In latter days, the harmful effects of SM have received attention, but they have yet been followed by greater encouragement of professionalized SM usage. SM use in medicine has seen adoption in parallel to its general ascendancy, even though the platforms are products with purposes misaligned with the practice of medicine. OBJECTIVE.­: To (1) characterize premises and forces that propel professional SM platform adoption and use, and (2) examine wide-ranging literature, both medical and nonmedical, that substantiates the premises and to find counteracting perspectives and evidence. DATA SOURCES.­: Review of the literature using relevant keyword searches in PubMed, Google Scholar, Dimensions, and Web of Science for articles that study/describe professional SM use in pathology and medicine. Additionally, we examined business, technology, and social sciences literature and high-quality gray literature (newspapers, books, blogs) that addressed questions in relation to the topic of professional SM adoption. CONCLUSIONS.­: We identified 6 major premises as motivators of professional SM use and highlight significant counteracting factors. We conclude that the harms of professionalized SM use have not been fully considered in the medical literature and that a change in direction and the creation of new communication platforms would be beneficial.

Anatomic pathology quality assurance: Developing an LIS based tracking and documentation module for intradepartmental consultations.

Background: An electronic intradepartmental consultation system for anatomic pathology (AP) was conceived and developed in the laboratory information system (LIS) in 2019. Previously, all surgical pathology intradepartmental consultative activities were initiated and documented with paper forms which circulated with the pertinent microscopic slides and were eventually filed. In this study, we discuss the implementation and utilization of an electronic intradepartmental AP consultation system. Methods: Workflows and procedures were developed to organize intradepartmental surgical pathology consultations from the beginning to the end point of the consultative activities entirely using a paperless system that resided in the LIS. Results: The electronic consult system allowed electronic documentation of all steps of intradepartmental consultative activities. The system provided tracking ability for consulted cases and improved access to consult discussion for all departmental personnel, staff, and trainees. Consultation work queue was created for each pathologist and a summary of individual consultative workload was possible. Documentation of anatomic pathology quality assurance for intradepartmental consultative activity was easily assessed. Conclusions: The electronic intradepartmental consult system has allowed our department to electronically track intradepartmental consult cases, store the consultative opinion text with the case, record the pathologists involved, and document the consultation for internal quality assurance review as well as for accrediting organizations. Summarization of pathologist workload related to consultative activity was quantifiable and optimization of the consultative process was maximized for education in an academic setting.

Frozen Section Quality Assurance.

OBJECTIVES: Composite frozen section turnaround time has limited value, precluding assessment of certain processes: slide preparation (technical) and diagnosis (interpretation). We examined whether measuring these elements could identify delays, hypothesizing that longer times were related to (1) inefficient technical processes and (2) case-specific diagnostic challenges. METHODS: Technical and interpretive times were determined for 1,992 specimens submitted for frozen section in 2017; the data were sorted by surgical specialty. Mean and quartile times were determined for each category with all specimens assessed equally, including those with multiple frozen section blocks. RESULTS: Technical times were significantly longer than interpretive times. Specialty grouping facilitated trend identification and enabled assessment of technical and interpretation challenges. We identified technical issues with certain gross specimens involving overdissection and interpretation delays for specific neoplasms and margins. CONCLUSIONS: Measuring technical and interpretative times and subcategorizing by specialty has aided the assessment of frozen section processing in our laboratory, enabling case isolation for process improvement.

Teaching Pathology in an Integrated Preclinical Medical School Curriculum and Adaptations to COVID-19 Restrictions.

The coronavirus disease 2019 (COVID-19) pandemic has had a major impact on education at all age levels, including professional schools and health professions programs. We describe the experience of adapting preclinical medical school courses within an integrated curriculum to virtual instruction. A major feature of two of the courses were pathology small groups adapted from pathology courses in the previous medical school curriculum. These small groups were designed to use facilitated groups of 8 to 10 students. With a sudden change to virtual learning, these small groups were shifted to large group virtual sessions. In general, the conversion went well, with ongoing optimization of the format of the large group sessions mainly occurring over the first several sessions. End-of-course student evaluations were generally positive, but with a preference toward returning to live sessions in the future. Scores on 5 multiple choice examinations in the spring 2020 course were essentially identical in mean, standard deviation, and distribution to examinations in the previous 2 years of the course that had similar layout and topic organization. We discuss the challenges and successes of the switch to virtual instruction and of teaching pathology content within an integrated medical school curriculum.

Rapid Validation of Whole-Slide Imaging for Primary Histopathology Diagnosis.

OBJECTIVES: The ongoing global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic necessitates adaptations in the practice of surgical pathology at scale. Primary diagnosis by whole-slide imaging (WSI) is a key component that would aid departments in providing uninterrupted histopathology diagnosis and maintaining revenue streams from disruption. We sought to perform rapid validation of the use of WSI in primary diagnosis meeting recommendations of the College of American Pathologists guidelines. METHODS: Glass slides from clinically reported cases from 5 participating pathologists with a preset washout period were digitally scanned and reviewed in settings identical to typical reporting. Cases were classified as concordant or with minor or major disagreement with the original diagnosis. Randomized subsampling was performed, and mean concordance rates were calculated. RESULTS: In total, 171 cases were included and distributed equally among participants. For the group as a whole, the mean concordance rate in sampled cases (n = 90) was 83.6% counting all discrepancies and 94.6% counting only major disagreements. The mean pathologist concordance rate in sampled cases (n = 18) ranged from 90.49% to 97%. CONCLUSIONS: We describe a novel double-blinded method for rapid validation of WSI for primary diagnosis. Our findings highlight the occurrence of a range of diagnostic reproducibility when deploying digital methods.

Spectrophotometric Analysis of Coronal Tooth Discoloration Induced by Tricalcium Silicate Cements in the Presence of Blood.

INTRODUCTION: New tricalcium silicate cements have been shown to induce less coronal discoloration. The purpose of this in vitro study was to evaluate the degree of color change induced by various silicate materials in the presence and absence of blood. METHODS: One hundred human extracted anterior single-canal teeth were sectioned to standardized root lengths, accessed, and instrumented. Eight random experimental groups and 2 control groups were created wherein specimens were filled with experimental materials below the buccal cementoenamel junction as follows: EndoSequence RRM putty (Brasseler USA, Savannah, GA), EndoSequence RRM fast set putty (Brasseler USA), Biodentine (Septodont, Saint-Maur-des-Fossés, France), and white mineral trioxide aggregate (Dentsply Sirona, York, PA) either with the presence or absence of blood. Blood-only and saline-only samples were used for the positive and negative controls. After incubation in 100% humidity at 37°C, color changes were evaluated with a spectrophotometer (Ocean Optics, Dunedin, FL) on days 0, 30, 60, and 180 after material placement. Data were transformed into Commission International de I'Eclairage's L∗a∗b color values, and corresponding ΔE values were calculated. The 1-way analysis of variance test was performed for statistical analysis. RESULTS: Discoloration was observed in all specimens in the presence of blood. There was no statistical significance when comparing different materials in contact with blood. Intragroup observation at various time points, Biodentine, and EndoSequence RRM fast set putty showed significant difference between the presence and absence of blood at 180 days (P < .05). CONCLUSIONS: Contamination with blood of tricalcium silicate materials has the potential to cause coronal tooth discoloration.

Lego bricks and the octet rule: Molecular models for biochemical pathways with plastic, interlocking toy bricks.

The 8 studs on a 2 × 4 Lego brick conveniently represent the outer shell of electrons for carbon, nitrogen, and oxygen atoms. We used Lego bricks to model these atoms, which are then joined together to form molecules by following the Lewis octet rule. A variety of small biological molecules can be modeled in this way, such as most amino acids, fatty acids, glucose, and various intermediate metabolites. Model building with these familiar toys can be a helpful, hands-on exercise for learning-or re-learning-biochemical pathways. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(1):54-57, 2018.