Transcriptome-wide association study and Mendelian randomization in pancreatic cancer identifies susceptibility genes and causal relationships with type 2 diabetes and venous thromboembolism.

BACKGROUND: Two important questions regarding the genetics of pancreatic adenocarcinoma (PDAC) are 1. Which germline genetic variants influence the incidence of this cancer; and 2. Whether PDAC causally predisposes to associated non-malignant phenotypes, such as type 2 diabetes (T2D) and venous thromboembolism (VTE). METHODS: In this study of 8803 patients with PDAC and 67,523 controls, we first performed a large-scale transcriptome-wide association study to investigate the association between genetically determined gene expression in normal pancreas tissue and PDAC risk. Secondly, we used Mendelian Randomization (MR) to analyse the causal relationships among PDAC, T2D (74,124 cases and 824,006 controls) and VTE (30,234 cases and 172,122 controls). FINDINGS: Sixteen genes showed an association with PDAC risk (FDR <0.10), including six genes not yet reported for PDAC risk (PPIP5K2, TFR2, HNF4G, LRRC10B, PRC1 and FBXL20) and ten previously reported genes (INHBA, SMC2, ABO, PDX1, MTMR6, ACOT2, PGAP3, STARD3, GSDMB, ADAM33). MR provided support for a causal effect of PDAC on T2D using genetic instruments in the HNF4G and PDX1 loci, and unidirectional causality of VTE on PDAC involving the ABO locus (OR 2.12, P < 1e-7). No evidence of a causal effect of PDAC on VTE was found. INTERPRETATION: These analyses identified candidate susceptibility genes and disease relationships for PDAC that warrant further investigation. HNF4G and PDX1 may induce PDAC-associated diabetes, whereas ABO may induce the causative effect of VTE on PDAC. FUNDING: National Institutes of Health (USA).

An integrated analysis of bile acid metabolism in humans with severe obesity.

BACKGROUND AND AIMS: Bile acids (BA) are vital regulators of metabolism. BAs are AQ6 secreted in the small intestine, reabsorbed, and transported back to the liver, where they can modulate metabolic functions. There is a paucity of data regarding the portal BA composition in humans. This study aimed to address this knowledge gap by investigating portal BA composition and the relation with peripheral and fecal BA dynamics in conjunction with the gut microbiome. APPROACH AND RESULTS: Thirty-three individuals from the BARIA cohort were included. Portal plasma, peripheral plasma, and feces were collected. BA and C4 levels were measured employing mass spectrometry. FGF19 was measured using ELISA. Gut microbiota composition was determined through metagenomics analysis on stool samples. Considerable diversity in the portal BA composition was observed. The majority (n = 26) of individuals had a 9-fold higher portal than peripheral BA concentration. In contrast, 8 individuals showed lower portal BA concentration compared with peripheral and had higher levels of unconjugated and secondary BA in this compartment, suggesting more distal origin. The altered portal BA profile was associated with altered gut microbiota composition. In particular, taxa within Bacteroides were reduced in abundance in the feces of these individuals. CONCLUSIONS: Characterization of the portal BA composition in relation to peripheral and fecal BA increased insight into the dynamics of BA metabolism in individuals with obesity. Peripheral BA composition was much more diverse due to microbial metabolism. About 24% of the portal samples was surprisingly low in total BA; the underlying mechanism requires further exploration.

Linking nursing students' professional identity, clinical learning environment, financial incentives, and career opportunities with migration intent: Structural equation modeling.

AIMS: To investigate how nursing students' professional identity, clinical learning environment, financial incentives, and career opportunities influence their intention to migrate. BACKGROUND: There is a preponderance of studies about nurse migration and its impact on the global nursing workforce. However, a critical gap remains about nursing students' intentions to migrate, particularly among developing countries like the Philippines. METHODS: Using a cross-sectional design, third- and fourth-year nursing students (n = 316) from the largest comprehensive university in Manila were conveniently recruited. Data were collected from November to December 2023 using five validated self-report scales. Descriptive (e.g., mean, standard deviation) and inferential statistics (e.g., Spearman rho, covariance-based structural equation modeling) were used to analyze data. RESULTS: The emerging model demonstrated acceptable model fit indices. Nursing students' professional identity (ß = 0.18, p = 0.043) and financial incentives (ß = 0.10, p = 0.046) significantly and positively influence the intention to migrate. The satisfaction with future career opportunities (ß = -0.12, p = 0.038) and clinical learning environment perception (ß = -0.15, p = 0.048) negatively influence the intention to migrate. These four predictors accounted for 4.60% of the total variance of intention to migrate. CONCLUSION: Nursing students' professional identity and financial incentives directly impact intent to migrate, whereas future career opportunities satisfaction and clinical learning environment inversely affect intent to migrate. IMPLICATIONS FOR NURSING PRACTICE AND POLICY: This study underscores the imperative for nursing colleges and faculty to promote positive professional identity and provide a conducive clinical learning environment to develop sustainable nurses' migration policies.

Follow-up of cystic pineal glands in retinoblastoma patients does not increase detection of pineal trilateral retinoblastoma.

PURPOSE: To evaluate the effectiveness of baseline screening and follow-up with MRI to detecting trilateral retinoblastoma (TRb) and assessing the risk of TRb development. DESIGN: Prospective multicenter cohort study METHODS: A total of 607 retinoblastoma patients from 2012 through 2022 were included and followed up until 1-9-2023. At each center a neuroradiologist categorized pineal glands on baseline and follow-up scans into four groups: (A) normal, (B) cystic gland, (C) suspicious gland, or (D) TRb. Different follow-up schedules were assigned to each category. Categories (B) and (C) were followed-up with MRI after approximately 3-months and after another 3 months if suspicion remained. On each MRI, they measured the height and width, evaluated the aspect (solid, partly cystic and completely cystic) of the pineal gland and evaluated radiological features suspicious of pineal TRb. The effectiveness of the current TRb screening method was assessed by evaluating its sensitivity and specificity to detect TRb. Determining the TRb incidence was a secondary outcome measure. RESULTS: Heritable retinoblastoma patients had a risk of 3.78% to develop TRb. One out of four pineal TRbs was detected during a follow-up scan and four out of five non-pineal TRbs were detected on the baseline MRI. Screening for pineal TRb had a sensitivity of 25% and specificity of 100%, for non-pineal TRb the sensitivity was 80%. It required 494 follow-up scans to detect one pineal TRb. However, when restricting the follow-up to solely suspicious glands, only 22 scans were required to detect one pineal TRb. CONCLUSION: During extended follow-up after baseline MRI, only one pineal trilateral retinoblastoma was detected in our study. Follow-up after three months should be restricted to patients with a suspicious pineal gland defined as irregularly thickening of the cyst wall (>2mm), fine nodular aspect of the cyst wall or when a solid or cystic gland exceeds the upper 99% prediction interval for size; patients with an unsuspicious cystic gland should not be followed up. Baseline MRI screening was able to detect most non-pineal trilateral retinoblastomas.

2,8-Disubstituted-1,5-naphthyridines as Dual Inhibitors of Plasmodium falciparum Phosphatidylinositol-4-kinase and Hemozoin Formation with In Vivo Efficacy.

Structure-activity relationship studies of 2,8-disubstituted-1,5-naphthyridines, previously reported as potent inhibitors of Plasmodium falciparum (Pf) phosphatidylinositol-4-kinase ß (PI4K), identified 1,5-naphthyridines with basic groups at 8-position, which retained Plasmodium PI4K inhibitory activity but switched primary mode of action to the host hemoglobin degradation pathway through inhibition of hemozoin formation. These compounds showed minimal off-target inhibitory activity against the human phosphoinositide kinases and MINK1 and MAP4K kinases, which were associated with the teratogenicity and testicular toxicity observed in rats for the PfPI4K inhibitor clinical candidate MMV390048. A representative compound from the series retained activity against field isolates and lab-raised drug-resistant strains of Pf. It was efficacious in the humanized NSG mouse malaria infection model at a single oral dose of 32 mg/kg. This compound was nonteratogenic in the zebrafish embryo model of teratogenicity and has a low predicted human dose, indicating that this series has the potential to deliver a preclinical candidate for malaria.

The challenges of treating status epilepticus in rural Canada.

Though unified by challenges in the treatment of status epilepticus (SE), rural Canada is simultaneously massive and diverse, spanning the Pacific, Atlantic, and Arctic Oceans. According to the national statistical agency, the most rural jurisdiction in Canada is the Arctic territory of Nunavut. In particular, the Kivalliq region of Nunavut represents a unique epidemiologic SE space because any treatment beyond typical first-line lorazepam and second-line phenytoin by a non-neurologist locum tenens requires airborne evacuation over a thousand kilometers away to a single hospital with a single electroencephalographic (EEG) laboratory. This distinctive mode of healthcare delivery affords unique insights into the challenges of treating SE in rural Canada, such as lack of EEG infrastructure, a markedly high incidence of SE, the struggles of enduring cultural and socioeconomic trauma, and a relative lack of local epilepsy care as recommended by the World Health Organization. For example, despite empiric treatment and waiting over 2 days on average for EEG, 1 in 5 patients still had ongoing or possible electrographic seizures. At the same time, Kivalliq experiences routine dramatic changes in light-dark exposure each year to afford unique insights into circannual SE chronobiology in relation to the chief human zeitgeber of sunlight. This shows that challenges may also represent opportunities, such as for existing and emerging technologies to synergistically address enormous treatment gaps to improve SE care for the people of Kivalliq, while providing novel insights that may also help improve SE clinical care around the world.

Chemical cyclization of tyrosine-containing peptides via in situ generated triazolinedione peptides.

Tyr-derived cyclic peptide natural products are formed by enzymatic manifolds that oxidatively cross-link embedded phenolic side chains of tyrosine (Tyr) and 4-hydroxyphenylglycine residues during their controlled production. Bioactive Tyr-derived cyclic peptides, such as the arylomycins and vancomycins, continue to motivate the development of enzymatic and chemical strategies for their de novo assembly and modification. However, chemical access to these structurally diverse natural cycles can be challenging and step intensive. Therefore, we developed an oxidative procedure to selectively convert Tyr-containing N4-substituted 1,2,4-triazolidine-3,5-dione peptides (urazole peptides) into stable Tyr-linked cyclic peptides. We show that Tyr-containing urazole peptides are simple to prepare and convert into reactive N4-substituted 1,2,4-triazoline-3,5-dione peptides by oxidation, which then undergo spontaneous cyclization under mildly basic aqueous conditions to form a cross-linkage with the phenol side chain of embedded Tyr residues. Using this approach, we have demonstrated access to over 25 Tyr-linked cyclic peptides (3- to 11-residue cycles) with good tolerance of native residue side chain functionalities. Importantly, this method is simple to perform, and product formation can be quickly confirmed by mass spectrometric and 1H NMR spectroscopic analyses.

Acute response to pathogens in the early human placenta at single-cell resolution.

The placenta is a selective maternal-fetal barrier that provides nourishment and protection from infections. However, certain pathogens can attach to and even cross the placenta, causing pregnancy complications with potential lifelong impacts on the child's health. Here, we profiled at the single-cell level the placental responses to three pathogens associated with intrauterine complications-Plasmodium falciparum, Listeria monocytogenes, and Toxoplasma gondii. We found that upon exposure to the pathogens, all placental lineages trigger inflammatory responses that may compromise placental function. Additionally, we characterized the responses of fetal macrophages known as Hofbauer cells (HBCs) to each pathogen and propose that they are the probable niche for T. gondii. Finally, we revealed how P. falciparum adapts to the placental microenvironment by modulating protein export into the host erythrocyte and nutrient uptake pathways. Altogether, we have defined the cellular networks and signaling pathways mediating acute placental inflammatory responses that could contribute to pregnancy complications.

Quinoxaline-Based Anti-Schistosomal Compounds Have Potent Anti-Malarial Activity.

The human pathogens Plasmodium and Schistosoma are each responsible for over 200 million infections annually, being particularly problematic in low- and middle-income countries. There is a pressing need for new drug targets for these diseases, driven by emergence of drug-resistance in Plasmodium and the overall dearth of new drug targets for Schistosoma. Here, we explored the opportunity for pathogen-hopping by evaluating a series of quinoxaline-based anti-schistosomal compounds for activity against P. falciparum. We identified compounds with low nanomolar potency against 3D7 and multidrug-resistant strains. Evolution of resistance using a mutator P. falciparum line revealed a low propensity for resistance. Only one of the series, compound 22, yielded resistance mutations, including point mutations in a non-essential putative hydrolase pfqrp1, as well as copy-number amplification of a phospholipid-translocating ATPase, pfatp2, a potential target. Notably, independently generated CRISPR-edited mutants in pfqrp1 also showed resistance to compound 22 and a related analogue. Moreover, previous lines with pfatp2 copy-number variations were similarly less susceptible to challenge with the new compounds. Finally, we examined whether the predicted hydrolase activity of PfQRP1 underlies its mechanism of resistance, showing that both mutation of the putative catalytic triad and a more severe loss of function mutation elicited resistance. Collectively, we describe a compound series with potent activity against two important pathogens and their potential target in P. falciparum.

MR Imaging of Adverse Effects and Ocular Growth Decline after Selective Intra-Arterial Chemotherapy for Retinoblastoma.

This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research.

Three-dimensional domain identification in a single hexagonal manganite nanocrystal.

The three-dimensional domain structure of ferroelectric materials significantly influences their properties. The ferroelectric domain structure of improper multiferroics, such as YMnO3, is driven by a non-ferroelectric order parameter, leading to unique hexagonal vortex patterns and topologically protected domain walls. Characterizing the three-dimensional structure of these domains and domain walls has been elusive, however, due to a lack of suitable imaging techniques. Here, we present a multi-peak Bragg coherent x-ray diffraction imaging determination of the domain structure in single YMnO3 nanocrystals. We resolve two ferroelectric domains separated by a domain wall and confirm that the primary atomic displacements occur along the crystallographic c-axis. Correlation with atomistic simulations confirms the Mexican hat symmetry model of domain formation, identifying two domains with opposite ferroelectric polarization and adjacent trimerization, manifesting in a clockwise arrangement around the hat's brim.

hERG, Plasmodium Life Cycle, and Cross Resistance Profiling of New Azabenzimidazole Analogues of Astemizole.

Toward addressing the cardiotoxicity liability associated with the antimalarial drug astemizole (AST, hERG IC50 = 0.0042 µM) and its derivatives, we designed and synthesized analogues based on compound 1 (Pf NF54 IC50 = 0.012 µM; hERG IC50 = 0.63 µM), our previously identified 3-trifluoromethyl-1,2,4-oxadiazole AST analogue. Compound 11 retained in vitro multistage antiplasmodium activity (ABS PfNF54 IC50 = 0.017 µM; gametocytes PfiGc/PfLGc IC50 = 1.24/1.39 µM, and liver-stage PbHepG2 IC50 = 2.30 µM), good microsomal metabolic stability (MLM CLint < 11 µL·min-1·mg-1, EH < 0.33), and solubility (150 µM). It shows a ∼6-fold and >6000-fold higher selectivity against human ether-á-go-go-related gene higher selectively potential over hERG relative to 1 and AST, respectively. Despite the excellent in vitro antiplasmodium activity profile, in vivo efficacy in the Plasmodium berghei mouse infection model was diminished, attributable to suboptimal oral bioavailability (F = 14.9%) at 10 mg·kg-1 resulting from poor permeability (log D7.4 = -0.82). No cross-resistance was observed against 44 common Pf mutant lines, suggesting activity via a novel mechanism of action.

Technical Considerations in Laparoscopic-Assisted Endoscopic Retrograde Cholangiography.

The use of endoscopic retrograde cholangiography (ERCP) for diagnostic and therapeutic interventions on the pancreaticobiliary system has steadily increased, but the standard approach through the oropharynx is prohibited after Roux-en-Y (RYGB) gastric bypass surgery. Laparoscopic access to the gastric remnant allows for the completion of ERCP using the standard side-viewing duodenoscope to facilitate the completion of standard and advanced endoscopic maneuvers. Here, we describe our experience with the technical aspects of safe and effective performance of laparoscopic-assisted ERCP.

High-definition transcranial direct current stimulation desynchronizes refractory status epilepticus.

Recently, we showed that high-definition transcranial direct current stimulation (hd-tDCS) can acutely reduce epileptic spike rates during and after stimulation in refractory status epilepticus (RSE), with a greater likelihood of patient discharge from the intensive care unit compared to historical controls. We investigate whether electroencephalographic (EEG) desynchronization during hd-tDCS can help account for observed anti-epileptic effects. Defining desynchronization as greater power in higher frequencies such as above 30 â€‹Hz ("gamma") and lesser power in frequency bands lower than 30 â€‹Hz, we analyzed 27 EEG sessions from 10 RSE patients who had received 20-minute session(s) of 2-milliamperes of transcranial direct current custom-targeted at the epileptic focus as previously determined by a clinical EEGer monitoring the EEG in real-time. During hd-tDCS, median relative power change over the EEG electrode chains in which power changes were maximal was +4.84%, -5.25%, -1.88%, -1.94%, and +4.99% for respective delta, theta, alpha, beta, and gamma frequency bands in the bipolar longitudinal montage (p â€‹= â€‹0.0001); and +4.13%, -5.44%, -1.81%, -3.23%, and +5.41% in the referential Laplacian montage (p â€‹= â€‹0.0012). After hd-tDCS, median relative power changes reversed over the EEG electrode chains in which power changes were maximal: -2.74%, +4.20%, +1.74%, +1.75%, and -4.68% for the respective delta, theta, alpha, beta, and gamma frequency bands in the bipolar longitudinal montage (p â€‹= â€‹0.0001); and +1.59%, +5.07%, +1.74%, +2.40%, and -5.12% in the referential Laplacian montage (p â€‹= â€‹0.0004). These findings are consistent with EEG desynchronization through theta-alpha-beta-gamma bands during hd-tDCS, helping account for the efficacy of hd-tDCS as an emerging novel anti-epileptic therapy against RSE.

Schreckstoff: It takes two to panic.

Schreckstoff (fear substance) is an alarm signal released by injured fish that induces a fear response. Its chemical nature has long been debated. A new study finds that zebrafish Schreckstoff is composed of at least three components, two of which elicit the fear response only in combination.

Oncogenic GNAS drives a gastric pylorus program in intraductal papillary mucinous neoplasms of the pancreas.

OBJECTIVE: Intraductal Papillary Mucinous Neoplasms (IPMNs) are cystic lesions and bona fide precursors for pancreatic ductal adenocarcinoma (PDAC). Recently, we showed that acinar to ductal metaplasia, an injury repair program, is characterized by a transcriptomic program similar to gastric spasmolytic polypeptide expressing metaplasia (SPEM), suggesting common mechanisms of reprogramming between the stomach and pancreas. The aims of this study were to assay IPMN for pyloric markers and to identify molecular drivers of this program. DESIGN: We analyzed RNA-seq studies of IPMN for pyloric markers, which were validated by immunostaining in patient samples. Cell lines expressing Kras G12D +/- GNAS R201C were manipulated to identify distinct and overlapping transcriptomic programs driven by each oncogene. A PyScenic-based regulon analysis was performed to identify molecular drivers in the pancreas. Expression of candidate drivers was evaluated by RNA-seq and immunostaining. RESULTS: Pyloric markers were identified in human IPMN. GNAS R201C drove expression of these markers in cell lines and siRNA targeting of GNAS R201C or Kras G12D demonstrates that GNAS R201C amplifies a mucinous, pyloric phenotype. Regulon analysis identified a role for transcription factors SPDEF, CREB3L1, and CREB3L4, which are expressed in patient samples. siRNA-targeting of Spdef inhibited mucin production. CONCLUSION: De novo expression of a SPEM phenotype has been identified in pancreatitis and a pyloric phenotype in Kras G12D -driven PanIN and Kras G12D ;GNAS R201C -driven IPMN, suggesting common mechanisms of reprogramming between these lesions and the stomach. A transition from a SPEM to pyloric phenotype may reflect disease progression and/or oncogenic mutation. IPMN-specific GNAS R201C amplifies a mucinous phenotype, in part, through SPDEF.

The AAHKS Clinical Research Award: Extended Postoperative Oral Tranexamic Acid in Total Knee Arthroplasty: A Randomized Controlled Pilot Study.

BACKGROUND: Perioperative tranexamic acid (TXA) use with total knee arthroplasty (TKA) is widely accepted today. Recently, a few international groups have published on the safety and outcomes of extending TXA use in the postoperative period. Through a double-blinded, randomized control trial (RCT), we aimed to investigate the safety and clinical efficacy of extended postoperative oral TXA use in TKA performed in an American, free-standing ambulatory surgery center (ASC). METHODS: Based on a power analysis, 40 patients undergoing primary TKA were randomized into 2 groups: extended oral TXA versus placebo. Both groups received a standard 1g intravenous TXA dose prior to incision and at the time of closure. The extended TXA group received an additional 1.95 g oral TXA dose following ambulation the day of surgery, plus on postoperative days 1,2, and 3. Patients who had a history of venous thromboembolism (VTE) or cancer were excluded. All patients received 81 mg of aspirin twice daily for VTE prophylaxis. Patients were followed on postoperative day 3 and weeks 2 and 6. Paired t-tests determined statistical significance. RESULTS: Extended TXA patients showed significantly increased knee flexion at 6 weeks (116.05 versus 106.5, P = .0308), improved VAS at 2 (2.5 versus 3.85, P = .039) and 6 weeks (1.35 versus 2.8, P = .011), and superior KOOS JR at 2 (66.87 versus 60.63, P = .03) and 6 weeks (73.33 versus 62.47, P = .0019) compared to placebo patients. No significant differences were found for changes in hemoglobin levels at any time points. No significant differences were found at 12 weeks for any clinical endpoints. No adverse events were noted in either cohort. CONCLUSIONS: When compared to placebo, the extended use of oral TXA in the postoperative period may safely result in improved motion, pain, and functional scores. Further investigation into 1-to-2-year outcomes, as well as the duration and dose of postoperative TXA use is warranted.

Insect genomics: A lousy fly.

The bee louse (Braula coeca) is a honeybee inquiline and a long-standing taxonomic mystery. A new study unravels their genomic architecture and shows that these enigmatic flies have evolved from scale insect-exploiting drosophilid ancestors and share genetic similarities with their honeybee hosts.

Tranexamic acid for angiotensin converting enzyme inhibitor induced angioedema: A retrospective multicenter study.

BACKGROUND: Angiotensin converting enzyme inhibitors (ACE-Is) prevent the breakdown of bradykinin and can lead to life threatening angioedema. Tranexamic acid is an antifibrinolytic that inhibits formation of precursors involved in bradykinin synthesis and, in case reports, has been described as a potential treatment for ACE-I angioedema. METHODS: This retrospective study included patients who presented to the emergency department (ED) from January 2018 to August 2021 with angioedema while taking an ACE-I. Patients who received tranexamic acid (treatment group) were compared with patients who did not receive tranexamic acid (control group). Primary outcome was length of stay (LOS). Secondary outcomes evaluated included ICU admissions, intubations, and safety events. RESULTS: A total of 262 patients were included in this study (73 treatment; 189 control). Overall, the median ED LOS was longer in the treatment group than controls (20.9 h vs 4.8 h, p < 0.001). ICU admission rates were higher in the treatment group (45% vs 16%, p < 0.001). More patients were intubated in the treatment group (12% vs 3%, p = 0.018). No difference was seen between the treatment group and the controls for return within 7 days, complications related to thrombosis, and death. In patients presenting with severe angioedema symptoms who were admitted to the hospital, median LOS was not different between the two groups (58.7 h vs 55.7 h, p = 0.61). CONCLUSIONS: Patients who received tranexamic acid had increased ED LOS, rates of ICU admission, and need for intubation. This finding may be related to the severity of presentation. Administration of tranexamic acid appears safe to use in ACE-I angioedema. Prospective randomized controlled studies should be considered to determine whether tranexamic acid is an effective treatment for ACE-I angioedema.