Hepatic Vasculopathy and Regenerative Responses of the Liver in Fatal Cases of COVID-19

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infects the nasopharynx and lungs and causes coronavirus disease-2019 (COVID-19). It may impact the heart, brain, kidney, and liver.1 Although functional impairment of the liver has been correlated with worse clinical outcomes, little is known about the pathophysiology of hepatic injury and repair in COVID-19.2,3 Histologic evaluation has been limited to small numbers of COVID-19 cases with no control subjects2,4 and demonstrated largely heterogeneous patterns of pathology.2,3.

First case of postmortem study in a patient vaccinated against SARS-CoV-2

A previously symptomless 86-year-old man received the first dose of the BNT162b2 mRNA COVID-19 vaccine. He died 4 weeks later from acute renal and respiratory failure. Although he did not present with any COVID-19-specific symptoms, he tested positive for SARS-CoV-2 before he died. Spike protein (S1) antigen-binding showed significant levels for immunoglobulin (Ig) G, while nucleocapsid IgG/IgM was not elicited. Acute bronchopneumonia and tubular failure were assigned as the cause of death at autopsy; however, we did not observe any characteristic morphological features of COVID-19. Postmortem molecular mapping by real-time polymerase chain reaction revealed relevant SARS-CoV-2 cycle threshold values in all organs examined (oropharynx, olfactory mucosa, trachea, lungs, heart, kidney and cerebrum) except for the liver and olfactory bulb. These results might suggest that the first vaccination induces immunogenicity but not sterile immunity.

Feasibility study for ex vivo fluorescence confocal microscopy (FCM) on diagnostic prostate biopsies

Background

Fluorescence confocal microscopy (FCM) is a novel micro-imaging technique providing optical sections of examined tissue. The method has been well established for the diagnosis of tumours in dermatological specimens. Preliminary results found good feasibility when this technique was used to examine prostate cancer (PCa) specimens.

Methods

We report on the application of FCM in magnet resonance imaging (MRI)-fused prostate biopsies (10 patients, total number of biopsy specimens: n=121) and compare the results to conventional histology.

Results

Specific structures of the prostatic tissue were very well represented in the FCM images comparable to conventional histology. Prostate carcinoma was diagnosed with good sensitivity (79/68%) and high specificity (100%) by two pathologists with substantial/almost perfect levels of agreement with the results of conventional histology (kappa 0.79/0.86). Depending on the quality of the scans, malignant lesions of 1.8 mm and more in diameter were reliably diagnosed. Smaller lesions were rated as suspect for malignancy, but could not be consistently differentiated from reactive changes. Optimal image qualities were achieved in focus depths of up to 50 µm, whereas deeper scans led to insufficient representation of cytological features. Pre-treatment with acridine orange (AO) did not alter immunoreactivity of the tissue or its feasibility for fluorescence in situ hybridization (FISH) analyses and adequate amounts of DNA could be extracted for further polymerase chain reaction (PCR)-based examinations.

Conclusions

FCM seems to be a promising tool for the timely diagnosis in cases of PCa in patients requiring therapy. In particular, this technique is a material-sparing method that conserves the biopsies as unfixed material for further analysis such as molecular tumour companion diagnosis.

Clinical profiles of post-load glucose subgroups and their association with glycaemic traits over time: An IMI-DIRECT study

AIM

To examine the hypothesis that, based on their glucose curves during a seven-point oral glucose tolerance test, people at elevated type 2 diabetes risk can be divided into subgroups with different clinical profiles at baseline and different degrees of subsequent glycaemic deterioration.

METHODS

We included 2126 participants at elevated type 2 diabetes risk from the Diabetes Research on Patient Stratification (IMI-DIRECT) study. Latent class trajectory analysis was used to identify subgroups from a seven-point oral glucose tolerance test at baseline and follow-up. Linear models quantified the associations between the subgroups with glycaemic traits at baseline and 18 months.

RESULTS

At baseline, we identified four glucose curve subgroups, labelled in order of increasing peak levels as 1-4. Participants in Subgroups 2-4, were more likely to have higher insulin resistance (homeostatic model assessment) and a lower Matsuda index, than those in Subgroup 1. Overall, participants in Subgroups 3 and 4, had higher glycaemic trait values, with the exception of the Matsuda and insulinogenic indices. At 18 months, change in homeostatic model assessment of insulin resistance was higher in Subgroup 4 (β = 0.36, 95% CI 0.13-0.58), Subgroup 3 (β = 0.30; 95% CI 0.10-0.50) and Subgroup 2 (β = 0.18; 95% CI 0.04-0.32), compared to Subgroup 1. The same was observed for C-peptide and insulin. Five subgroups were identified at follow-up, and the majority of participants remained in the same subgroup or progressed to higher peak subgroups after 18 months.

CONCLUSIONS

Using data from a frequently sampled oral glucose tolerance test, glucose curve patterns associated with different clinical characteristics and different rates of subsequent glycaemic deterioration can be identified.

[Uncommon tumor of the gastric wall]

We report on a 72-year-old male patient suffering from weight loss, diarrhea, and epigastric pain. By means of endosonographic ultrasound, a well-circumscribed tumor mass was found in the gastric wall, suggesting a gastrointestinal stromal tumor (GIST). Biopsies were taken and processed for standard histopathological analysis. The microscopy revealed uniform, small, round cells with central nuclei and prominent cell borders embedded in vascularized stroma. Immunohistochemistry demonstrated the expression of actin, but showed negativity for cytokeratin, CD34, CD117, DOG‑1, desmin, and CD45. The tumor was diagnosed as a gastral glomus tumor. The diagnosis was confirmed in the wedge resection specimen. Gastral glomus tumors are rare intramural tumors of the stomach. GIST and neuroendocrine tumor (NET) present the main differential diagnoses. Especially with regard to the epithelioid variant of GIST, clear separation can be difficult. Besides standard histological examination, immunohistochemistry and molecular analysis can be helpful since gastral glomus tumors do not obtain c‑Kit- or PDGFRα mutations. Based on the fact that this tumor most commonly shows a benign biological behavior, the prognosis of gastral glomus tumors is favorable.

Uncommon finding of a "black node" in a patient with malignant melanoma and arthroplasty: A case report

Postarthroplasty lymphadenopathy should be kept in mind particularly in patients with tumor (eg, melanoma) with a long-term history of total joint replacement therapy. Microscopy is mandatory in establishing diagnosis and is thus helpful for therapy.

Circulating immune cell profiles detected by mass cytometry differ significantly between patients with predominantly calcified and predominantly non-calcified coronary atherosclerosis

Background/Introduction

Inflammation is now a well-established component of the pathophysiology of coronary artery disease (CAD), but it is unknown whether atherosclerosis is associated with a distinct circulating immune cell profile. Mass cytometry time-of-flight (CYTOF) is a new precision technology which can be used to assess leukocyte populations comprehensively.

Purpose

To determine if patients with calcified and non-calcified (soft) coronary plaque have distinct circulating immune cell profiles when compared to healthy controls, and to assess whether this could be used to detect sub-clinical CAD.

Methods

Patients referred for a CT coronary angiogram were recruited; blood samples were collected and peripheral blood mononuclear cells (PBMCs) were isolated. Imaging data was analysed using a modified Gensini scoring system which incorporated plaque composition, with higher weighting given to soft plaque. The modified Gensini scores were then used to further segregate into calcified-predominant and soft-predominant disease groups. CYTOF analysis was performed on the PBMCs, with groups as outlined in Table 1.

Results

Age was significantly higher in the CAD+ group, but all other demographic features and risk factors did not differ between groups. Patients with predominantly calcified disease showed an increase in memory CD8 T cells (p=0.004), an increase in CD 39+ CD4 T cells (p=0.028), and a decrease in naïve CD8 T cells (p=0.005), which suggests an accumulated memory response in more quiescent disease. Patients with predominantly soft-plaque disease have higher pro-inflammatory monocyte populations (p=0.013) and proliferative CD4 T cell populations (p=0.011), suggesting acute innate and adaptive responses to biologically active plaque.

Conclusions

This pilot study has shown that further study should be pursued into the utility of CYTOF to identify sub-clinical CAD through differences in peripheral circulating immune cell profiles.

Figure 1

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): National Health and Medical Research Council of Australia, Heart Research Australia

A28 RELATIVE RATES OF ULCERATIVE COLITIS TO CROHN’S DISEASE: PARALLEL EPIDEMIOLOGIES IN NEWLY VS. HIGHLY INDUSTRIALIZED COUNTRIES

Background

Inflammatory bowel disease (IBD) first presents in a population as cases of ulcerative colitis (UC) followed by cases of Crohn’s disease (CD). Newly industrialized countries (NIC) show a prallel epidemiology of IBD to highly industrialized countries (HIC) in the previous century; one marker of this is the relative incidence/prevalence rates of UC to CD, which approximates 1 over time.

Aims

Provide evidence for the UC:CD ratio as a proxy for disease penatrance in a population.

Methods

Systematic review of MedLine and Embase for studies reporting incidence or prevalence of UC and CD. Log-linear regression (by region and NIC/HIC [2019 United Nations definitions]) was used to calculate average annual percent change (AAPC) and associated 95% confidence intervals (CI). Data were plotted on an online, interactive map to show trends (link provided).

Results

We extracted data from 218 studies compising population-level data from 69 countries. We found negative AAPCs as the prevalence ratio of UC:CD significantly decreased over time in East Asia, West Asia, North Europe, and South Europe; 6/12 global regions displayed significantly decreasing incidence ratios. No AAPC was found to be significantly increasing (Table 1). When examing HIC/NIC, we found a significant effect of NIC on the UC:CD prevalence ratio after 2000 (AAPC:−3.83;95%CI:−6.28,−1.31) while HIC regions remained stable (AAPC:2.14;95%CI:−1.40,5.82). Looking at all available data, both HICs and NICs show significantly decreasing UC:CD prevalence ratios (HIC:AAPC:−3.72;95% CI:−4.46,−2.97; NIC:AAPC:−2.62;95%CI:−4.13,−1.08).

Conclusions

In some HICs (eg. Canada), the UC:CD incidence ratio was <1 in the earliest available data (1966), explaining the stable AAPC in North America (AAPC:−0.24;95%CI:−1.12,0.65). However, in NICs (eg. Southern Asia), the AAPC is rapidly decreasing (AAPC:−24.68;95%CI:−37.85,−8.71) as areas like Sri Lanka rapidly fall from an incidence ratio of 7.5 (2007) to 2.8 (2012), mimicking trends in IBD epidimeology of HICs in the previous century.

Funding Agencies

None

A248 WHAT IS THE MINIMUM TRAINING STANDARD FOR POINT OF CARE INTESTINAL ULTRASOUND? A SINGLE CENTER, PROSPECTIVE, OBSERVATIONAL STUDY TO DEFINE TRAINING STANDARDS

Background

Higher demands for colonoscopy and magnetic resonance imaging (MRI) for long term disease monitoring can be expected as the prevalence of IBD continues to rise in Canada. As resources are perpetually constrained, timely access to effective monitoring strategies important to direct care are increasingly compromised. Intestinal ultrasound provides a cost-effective solution to these challenges. Intestinal ultrasound (IUS) is a patient-centered, accurate modality used during clinic by non-radiologists to enhance clinical decision making. Minimum IUS training standards have yet to be established.

Aims

The aim of this study is to report a single operator IUS performance characteristics after completion of 4 weeks of training with 100 completed supervised scans.

Methods

A single center, prospective, observational study over 4 years utilizing a convenience sample of patients presenting to the inflammatory bowel disease (IBD) clinic at the University of Calgary. A single operator compared IUS to gold standard (either colonoscopy, or alternative cross-sectional imaging) with sensitivity, specificity, positive and negative predictive value calculated for each year. Joinpoint regression was performed to analyze the trend for sensitivity and specificity over the study period.

Results

A total of 235 IUS were performed on 235 individuals diagnosed with IBD between 2013 and 2016. There were individuals with 26 ulcerative colitis and 209 persons diagnosed with Crohn’s disease. There was a non-significant increase in sensitivity and specificity point estimates over the 4 year period (Table 1). The sensitivity, specificity, positive predictive value, and accuracy of IUS in 2016 were 100% (95% CI: 81%-100%), 92% (95% CI: 62%-100%), 94% (95% CI: 72%-99%) and 97% (95% CI: 8%-100%) respectively.

Conclusions

IUS provision by a gastroenterologist having completed 100 supervised scans during training within an expert center is sufficient, resulting in high accuracy. Although there is some improvement over time, the trend towards improvement over time is not significant. This study provides evidence to inform IUS training programs with a minimum training standard benchmark, imperative with expanding demand and development of new expert centers.

Funding Agencies

None

Improving the background of gravitational-wave searches for core collapse supernovae: a machine learning approach

Based on the prior O1–O2 observing runs, about 30% of the data collected by Advanced LIGO and Virgo in the next observing runs are expected to be single-interferometer data, i.e. they will be collected at times when only one detector in the network is operating in observing mode. Searches for gravitational-wave signals from supernova events do not rely on matched filtering techniques because of the stochastic nature of the signals. If a Galactic supernova occurs during single-interferometer times, separation of its unmodelled gravitational-wave signal from noise will be even more difficult due to lack of coherence between detectors. We present a novel machine learning method to perform single-interferometer supernova searches based on the standard LIGO-Virgo coherent WaveBurst pipeline. We show that the method may be used to discriminate Galactic gravitational-wave supernova signals from noise transients, decrease the false alarm rate of the search, and improve the supernova detection reach of the detectors.

102 A delay in maternal zygotic transition may lead to early embryonic loss in poor-quality bovine blastocysts

Increased genetic potential and performance of dairy cows has coincided with a decline in fertility. Early embryonic mortality accounts for 75-80% of this decline in fertility, costing the industry over $1.28 trillion worldwide. Despite advancements in assisted reproductive technologies and embryo transfer, many transferred embryos do not survive past Day 24 of gestation, suggesting flaws in embryo selection for transfer. It was hypothesised that visually lower-quality IVF Day 7 blastocysts were developmentally delayed as a result of altered mitotic signalling and were at higher risk of embryo mortality. To identify potential causes for early embryo mortality in IVF embryos, RNA-Seq was performed on 6 categories of Day 7 blastocysts: stages (S) 5 (early), 6 (full), and 7 (expanded), with quality scores (Q) of 1 or 2. Oocytes were matured, fertilized by routine procedure, and cultured for 7 days. Blastocysts were classified and graded, separated into the six categories, and subjected to Pronase digestion of the zona pellucida. From three biological replicates of each blastocyst group, RNA was extracted and submitted for RNA-sequencing. Secondary bioinformatics and analyses were performed using R to determine differentially expressed genes. When S7.Q1 blastocysts were compared to other categories, 55 genes were consistently differentially expressed (P<0.05) in S5.Q1 or 2 and S6.Q2. Of these 55 genes, 15 were significantly upregulated (>1.5 fold change), and 40 were downregulated (<−1.5 fold change). The nine most common upregulated genes in S5.Q1 or 2 and S6.Q2, compared with S7.Q1, were BTG4, ARGFX, GPC4, BOC, CNTNAP2, NR3C2, CCDC7, and PHYHIPL. The five most common downregulated genes included MUC1, HSD3B1, ADAM19, EVPL, and TGM1. The EVPL and TGM1 proteins are associated with cell barrier permeability, and a lack of TGM1 has been shown to cause neonatal death in mice. Therefore, early embryo mortality may begin with decreased EVPL and TGM1, limiting cell permeability and communication between blastomeres. This limited communication might delay gene expression in the embryo at the 4- to 8-cell stage, delaying the maternal zygotic transition (MZT), in spite of continued cell division. This explanation is supported by the observed increase in ARGFX and BTG4 mRNA. Normally, stored maternal BTG4 mRNA becomes translated during the MZT and degrades maternal mRNA. The increase of BTG4 mRNA in poor-quality embryos may reflect delayed translation of BTG4 and delayed MZT. The mRNA transcripts increased in poor-quality blastocysts may be excess maternal mRNA not yet degraded, like BTG4. The decreased mRNA transcripts observed may be indicative of zygotic genes which have not yet been transcribed. For instance, MUC1 is necessary for proper embryo implantation, and HSD3B1 converts placental pregnenolone to progesterone and produces a precursor to oestradiol. The delayed transcription of both MUC1 and HSD3B1 may impair maternal recognition of pregnancy, implantation, and communication to the maternal endometrium via oestradiol, thereby causing embryo mortality. This research was supported by USDA NNF 2016-38420-25289 and Zoetis Inc.

Normal radiological lymph node appearance in the thorax

Modern treatment of esophageal cancer is multimodal and highly dependent on a detailed diagnostic assessment of clinical stage, which includes nodal stage. Clinical appraisal of nodal stage is highly dependent on knowledge of normal radiological appearance, information of which is scarce. We aimed to describe lymph node appearance on computed tomography (CT) investigations in a randomly selected cohort of healthy subjects. In a sample of the Swedish Cardiopulmonary bioimage study, which investigates a sample of the Swedish population aged 50-64 years, the CT scans of 426 subjects were studied in detail concerning intrathoracic node stations relevant in clinical staging of esophageal cancer. With stratification for sex, the short axis of visible lymph nodes was measured and the distribution of lymph node sizes was calculated as well as proportion of patients with visible nodes above 5 and 10 millimeters for each station. Probability of having any lymph node station above 5 and 10 millimeters was calculated with a logistic regression model adjusted for age and sex. In the 214 men (aged: 57.3 ± 4.1 years) and 212 women (aged: 57.8 ± 4.4 years) included in this study, a total of 309 (72.5%) had a lymph node with a short axis of 5 mm or above was seen in at least one of the node stations investigated. When using 10 mm as a cutoff, nodes were visible in 29 (6.81%) of the subjects. Men had higher odds of having any lymph node with short axis 5 mm or above (OR 3.03 95% CI 1.89-4.85, P < 0.001) as well as 10 mm or above (OR 2.31 95% CI 1.02-5.23, P = 0.044) compared to women. Higher age was not associated with propensity for lymph nodes above 5 or 10 millimeters in this sample. We conclude that, in a randomly selected cohort of patients between 50 and 64 years, almost 10% of the men and 4% of the women had lymph nodes above 10 millimeters, most frequently in the subcarinal station (station 107). More than half of the patients had nodes above 5 millimeters on CT and men were much more prone to have this finding. The probability of finding lymph nodes in specific stations relevant of esophageal cancer is now described.

P6271The effect of semaglutide once weekly on MACE and blood pressure by race and ethnicity: SUSTAIN 6 post hoc analysis

Background

In SUSTAIN 6, subcutaneous semaglutide once weekly added to standard of care significantly reduced major adverse cardiovascular events (MACE: non-fatal myocardial infarction, non-fatal stroke or death) vs placebo over 2 years in T2D subjects.

Purpose

Assess the effect of semaglutide vs placebo on MACE and blood pressure (BP) by race and ethnicity in a post hoc analysis of SUSTAIN 6.

Methods

Subjects were randomised to semaglutide 0.5 mg, 1.0 mg or volume-matched placebo. Data for the two semaglutide-dose groups were pooled and compared to the pooled placebo groups. Time-to-event data were analysed with a Cox proportional hazards model. Changes from baseline to week 104 were analysed using analysis of covariance. The interaction between treatment and subgroup was added to the models.

Results

Overall, 3,297 patients received treatment. Subgroups included Caucasian, Asian, Black/African American, Other (race), and Hispanic, non-Hispanic (ethnicity). Mean baseline characteristics were similar across subgroups (age 64.7 years, HbA1c 8.7%, diabetes duration 14.2 years). Time to composite MACE and individual components were improved with semaglutide across all subgroups. Semaglutide affected BP similarly across race and ethnicity, except for systolic BP in Black/African American subjects (Table).

Race Ethnicity Caucasian Asian Black/African American Other Interaction p-value Hispanic Non-Hispanic Interaction p-value Semaglutide (n) 1,384 121 108 35 256 1,392 Placebo (n) 1,352 152 113 32 254 1,395 MACE and individual outcomes   MACE HR [95% CI] 0.76 [0.58; 1.00] 0.58 [0.25; 1.34] 0.72 [0.23; 2.28] 0.46 [0.08; 2.50] 0.8793 0.67 [0.33; 1.36] 0.74 [0.57; 0.96] 0.7978   CV death HR [95% CI] 0.98 [0.63; 1.50] 0.32 [0.04; 2.85] 1.01 [0.06; 16.20] n/a† 0.8089 0.79 [0.31; 2.00] 1.00 [0.63; 1.59] 0.6521   Non-fatal MI HR [95% CI] 0.69 [0.45; 1.07] 0.97 [0.36; 2.60] 1.37 [0.31; 6.12] 0.31 [0.03; 3.00] 0.6637 0.65 [0.18; 2.31] 0.74 [0.50; 1.10] 0.8562   Non-fatal stroke HR [95% CI] 0.70 [0.42; 1.16] 0.31 [0.04; 2.77] n/a‡ n/a‡ 0.9176 0.73 [0.16; 3.27] 0.60 [0.36; 0.99] 0.7995 Blood pressure at week 104   Systolic BP* ETD (mmHg) [95% CI] −1.92 [−3.09; −0.74] −4.98 [−8.61; 1.35] 4.47 [0.15; 8.79] −11.02 [−18.45; −3.60] 0.0008 −3.22 [−5.93; −0.51] −1.81 [−2.98; −0.64] 0.3489   Diastolic BP* ETD (mmHg) [95% CI] 0.36 [−0.32; 1.04] −1.31 [−3.43; 0.80] −0.07 [−2.56; 2.43] −3.41 [−7.73; 0.92] 0.1871 −0.18 [−1.75; 1.39] 0.16 [−0.52; 0.83] 0.6981 *Treatment difference between semaglutide and placebo (pooled 0.5 and 1.0 mg values for each treatment group) at week 104. †No events in the placebo group; ‡No events in the semaglutide group. BP, blood pressure; CI, confidence interval; ETD, estimated treatment difference; HR, hazard ratio; MACE, major adverse cardiovascular event; MI, myocardial infarction.

Conclusion

Overall there was no evidence of a differential effect of semaglutide on risk reduction in MACE and its components and on BP across race and ethnicity subgroups in this post hoc analysis.

Acknowledgement/Funding

Novo Nordisk A/S

[Bronchoalveolar lavage in hairy cell leukemia with pulmonary infiltration]

We report a 78-year-old male patient suffering from hairy cell leukemia, presenting clinically mainly with dyspnea. Radiology exhibited bilateral ground-glass shadows. In order to prevent pneumonia as a possible side effect due to conventional chemotherapy, it was decided to first treat the patient with rituximab; however, dyspnea persisted. Therefore, bronchoscopy was performed and specimens were sampled for both histological examination and bronchoalveolar lavage (BAL) analysis. BAL showed lymphocytosis (28.7%), and by means of immunocytochemistry a few CD79a+ B‑lymphocytes as well as lymphoid cells positive for the hairy cell marker DBA44 were observed. In addition, molecular study revealed the BRAF V600E mutation. Thus, the findings of BAL were interpreted as lung infiltration by hairy cell leukemia. This result was confirmed by histology. Following a therapy switch to cladribine, a significant improvement was reached. Pulmonary infiltrates by hairy cell leukemia were rarely described. This case represents the first report of hairy cell leukemia diagnosed by means of BAL. It may be difficult to clearly separate between lymphoma infiltration of the lung and medicamentous pneumonitis, but this differential diagnosis can be supported by morphological methods.