Observation of fractional edge excitations in nanographene spin chains.

Fractionalization is a phenomenon in which strong interactions in a quantum system drive the emergence of excitations with quantum numbers that are absent in the building blocks. Outstanding examples are excitations with charge e/3 in the fractional quantum Hall effect1,2, solitons in one-dimensional conducting polymers3,4 and Majorana states in topological superconductors5. Fractionalization is also predicted to manifest itself in low-dimensional quantum magnets, such as one-dimensional antiferromagnetic S = 1 chains. The fundamental features of this system are gapped excitations in the bulk6 and, remarkably, S = 1/2 edge states at the chain termini7-9, leading to a four-fold degenerate ground state that reflects the underlying symmetry-protected topological order10,11. Here, we use on-surface synthesis12 to fabricate one-dimensional spin chains that contain the S = 1 polycyclic aromatic hydrocarbon triangulene as the building block. Using scanning tunnelling microscopy and spectroscopy at 4.5 K, we probe length-dependent magnetic excitations at the atomic scale in both open-ended and cyclic spin chains, and directly observe gapped spin excitations and fractional edge states therein. Exact diagonalization calculations provide conclusive evidence that the spin chains are described by the S = 1 bilinear-biquadratic Hamiltonian in the Haldane symmetry-protected topological phase. Our results open a bottom-up approach to study strongly correlated phases in purely organic materials, with the potential for the realization of measurement-based quantum computation13.

What can lattice DFT teach us about real-space DFT?

In this paper we establish a connection between density functional theory (DFT) for lattice models and common real-space DFT. We consider the lattice DFT description of a two-level model subject to generic interactions in Mermin's DFT formulation in the grand canonical ensemble at finite temperature. The case of only density-density and Hund's rule interaction studied in earlier work is shown to be equivalent to an exact-exchange description of DFT in the real-space picture. In addition, we also include the so-called pair-hopping interaction which can be treated analytically and, crucially, leads to non-integer occupations of the Kohn-Sham (KS) levels even in the limit of zero temperature. Treating the hydrogen molecule in a minimal basis is shown to be equivalent to our two-level lattice DFT model. By means of the fractional occupations of the KS orbitals (which, in this case, are identical to the many-body ones) we reproduce the results of full configuration interaction, even in the dissociation limit and without breaking the spin symmetry. Beyond the minimal basis, we embed our HOMO-LUMO model into a standard DFT calculation and, again, obtain results in overall good agreement with exact ones without the need of breaking the spin symmetry.

Provider Attitudes Toward Risk-Based Hepatocellular Carcinoma Surveillance in Patients With Cirrhosis in the United States.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) surveillance rates are suboptimal in clinical practice. We aimed to elicit providers' opinions on the following aspects of HCC surveillance: preferred strategies, barriers and facilitators, and the impact of a patient's HCC risk on the choice of surveillance modality. METHODS: We conducted a web-based survey among gastroenterology and hepatology providers (40% faculty physicians, 21% advanced practice providers, 39% fellow-trainees) from 26 US medical centers in 17 states. RESULTS: Of 654 eligible providers, 305 (47%) completed the survey. Nearly all (98.4%) of the providers endorsed semi-annual HCC surveillance in patients with cirrhosis, with 84.2% recommending ultrasound ± alpha fetoprotein (AFP) and 15.4% recommending computed tomography (CT) or magnetic resonance imaging (MRI). Barriers to surveillance included limited HCC treatment options, screening test effectiveness to reduce mortality, access to transportation, and high out-of-pocket costs. Facilitators of surveillance included professional society guidelines. Most providers (72.1%) would perform surveillance even if HCC risk was low (≤0.5% per year), while 98.7% would perform surveillance if HCC risk was ≥1% per year. As a patient's HCC risk increased from 1% to 3% to 5% per year, providers reported they would be less likely to order ultrasound ± AFP (83.6% to 68.9% to 57.4%; P < .001) and more likely to order CT or MRI ± AFP (3.9% to 26.2% to 36.1%; P < .001). CONCLUSIONS: Providers recommend HCC surveillance even when HCC risk is much lower than the threshold suggested by professional societies. Many appear receptive to risk-based HCC surveillance strategies that depend on patients' estimated HCC risk, instead of our current "one-size-fits all" strategy.

The COVID-19 Pandemic Highlights Opportunities to Improve Hepatocellular Carcinoma Screening and Diagnosis in a National Health System.

INTRODUCTION: We evaluated the coronavirus disease 2019 (COVID-19) pandemic's impact on hepatocellular carcinoma (HCC) screening and diagnosis among patients with cirrhosis in the Veterans Health Administration. METHODS: Rates and predictors of screening and diagnosis were reviewed September 1, 2019-February 29, 2020 ("pre-COVID-19," N = 94,612) and April 1, 2020-September 30, 2020 ("post-COVID-19," N = 88,073). RESULTS: Screening and diagnosis rates declined by 44% and 13%, respectively, after the COVID-19 pandemic. Screening declined irrespective of liver disease severity, but diagnosis declined only in Model for End Stage Liver Disease-Sodium score <20 or Fibrosis-4 score <3.25. Fibrosis-4 score ≥3.25 and HCC risk ≥1.5%/year strongly predicted HCC diagnosis but only moderately predicted receipt of screening. DISCUSSION: Screening and diagnosis rates declined after the COVID-19 pandemic. Prioritizing screening for patients at greatest risk for HCC may reduce delays in diagnosis.

Rates and Predictors of Undergoing Different Hepatocellular Carcinoma Screening Tests in Patients With Cirrhosis.

INTRODUCTION: We aimed to assess rates and predictors of hepatocellular carcinoma (HCC) screening among patients with cirrhosis. METHODS: We reviewed electronic health records of 11,361 patients with cirrhosis from 11 U.S. Veterans Health Administration facilities for receipt of HCC screening in the 6 months preceding October 1, 2019. RESULTS: Nearly half of the cohort (46%) received HCC screening over a 6-month period. Screening rates and modalities (ultrasound, computed tomography, magnetic resonance imaging, serum alpha fetoprotein) varied by facility. Screening was associated with race/ethnicity, body mass index ≥ 25, cirrhosis etiology, thrombocytopenia, Fibrosis-4 ≥ 3.25, and lower Model for End-Stage Liver Disease-Sodium. DISCUSSION: HCC screening rates varied by facility. Higher risk patients were more likely to receive screening.

Mott Metal-Insulator Transition from Steady-State Density Functional Theory.

We present a computationally efficient method to obtain the spectral function of bulk systems in the framework of steady-state density functional theory (i-DFT) using an idealized scanning tunneling microscope (STM) setup. We calculate the current through the STM tip and then extract the spectral function from the finite-bias differential conductance. The fictitious noninteracting system of i-DFT features an exchange-correlation (XC) contribution to the bias which guarantees the same current as in the true interacting system. Exact properties of the XC bias are established using Fermi-liquid theory and subsequently implemented to construct approximations for the Hubbard model. We show for two different lattice structures that the Mott metal-insulator transition is captured by i-DFT.

Electrically Addressing the Spin of a Magnetic Porphyrin through Covalently Connected Graphene Electrodes.

We report on the fabrication and transport characterization of atomically precise single-molecule devices consisting of a magnetic porphyrin covalently wired by graphene nanoribbon electrodes. The tip of a scanning tunneling microscope was utilized to contact the end of a GNR-porphyrin-GNR hybrid system and create a molecular bridge between the tip and sample for transport measurements. Electrons tunneling through the suspended molecular heterostructure excited the spin multiplet of the magnetic porphyrin. The detachment of certain spin centers from the surface shifted their spin-carrying orbitals away from an on-surface mixed-valence configuration, recovering its original spin state. The existence of spin-polarized resonances in the free-standing systems and their electrical addressability is the fundamental step in the utilization of carbon-based materials as functional molecular spintronics systems.

["Drug Interaction Stewardship" (DIS) and Therapeutic Drug Monitoring for Anti-infective Treatment in Intensive Care, a Single Centre Observational Study]. / "Drug Interaction Stewardship" (DIS) und therapeutisches Drug-Monitoring (TDM) für die antiinfektive Therapie in der operativen Intensivmedizin, eine monozentrische Beobachtungsstudie.

INTRODUCTION: Appropriate medication of intensive care patients is complicated by disturbed organ functions and organ failure, pathophysiological changes in severely ill patients as well as possible sepsis, ongoing haemodialysis for renal and hepatic insufficiency, varying pharmacokinetics/-dynamics (PK/PD) of drugs as well as numerous drug interactions. AIM: Illustration of an interdisciplinary approach in daily clinical practice to optimise regular "polymedication" as well as the ongoing medication of patients prior to surgical interventions as indicated and as part of the appropriate peri- and postoperative intensive care management. METHOD: A so-called "drug interaction stewardship" (DIS) is very similar to the already established "antibiotic stewardship" (ABS) during daily clinical routine of an intensive care unit and has been implemented. In addition, therapeutic drug monitoring (TDM) has been extended to antibiotics/antimycotics (such as meropenem, piperacillin-tazobactam, ceftazidime, linezolide, voriconazole, fluconazole, caspofungin), for which TDM had not yet been established. This was in a consecutive cohort of patients with abdominal surgery over a defined time period and was part of a systematic clinical single centre observational study (tertiary centre). RESULTS: From 01 - 2012 to 08 - 2016, 1,454 single drug patient consultations led to 385 (26.5%) changes in medical treatment, which had been previously initiated by an experienced intensive care physician. Most frequently in 156 cases (10.7%) this was due to newly calculated PK/PD. Analysis of 2,333 TDM samples resulted in a minimum serum level within the adequate range in 1,130 cases (48.4%). In 427 cases (18.3%), the drug serum level was too low and in 776 subjects (33.3%), prompting a change in the type, dose, dose interval and application route. CONCLUSION: DIS and TDM provide a high rate of detection of unwanted drug interactions and inappropriate drug levels in surgical intensive care patients and help to assure targeted therapy changes.

Increased HCV Screening Yields Discordant Gains in Diagnoses Among Urban and Rural Veteran Populations in Texas: Results of a Statewide Quality Improvement Initiative.

BACKGROUND: Chronic hepatitis C virus (HCV) infection is a significant health burden among military veterans. Our goals were to increase monthly HCV screenings, diagnoses, and sustained virologic responses (SVR) among 88,652 unscreened birth cohort Veterans in Texas. METHODS: The interventions were enabled within six of the eight healthcare systems (HCSs) that compose Veteran's Integrated Service Network 17. The remaining two HCSs served as controls. The HCSs were separated into two groups: urban and rural; each composed of a control and three interventional HCSs. Decision support programming was embedded within the Computerized Patient Record System that prompted HCV screening among previously unscreened birth cohort patients. Clinical process design and educational efforts were enacted to enhance treatment capacity. RESULTS: Monthly screenings increased 4.89 times (p < 0.001) and 2.97 times (p < 0.001) during the postinterventional period relative to control for urban and rural HCSs, respectively. For urban HCSs, diagnoses increased 1.58 (p < 0.001) times more than the control group during the postinterventional period, but there was no difference in number of diagnoses in the rural HCSs (p = 0.86). Monthly SVR increased 2.69 times more than the control group during the postinterventional period (p < 0.001). CONCLUSION: Decision support improved HCV screening among birth cohort patients in both urban and rural HCSs. Increased screening boosted the monthly number of diagnoses in the urban HCSs, but not in the rural HCSs; which rebuts the utility of birth cohort screening among rurally residing veterans. These interventions significantly improved the rate of SVR achievement relative to control.

Increasing access for veterans with hepatitis C by enhancing use of clinical pharmacy specialists.

OBJECTIVES: To increase access to hepatitis C virus (HCV) care and cure by deploying clinical pharmacy specialist (CPS) providers across the largest integrated health care system in the United States. SETTING: National integrated health care system. PRACTICE DESCRIPTION: In late 2016, the Department of Veterans Affairs (VA) Pharmacy Benefits Management Clinical Pharmacy Practice Office (CPPO) partnered with the VA HIV, Hepatitis, and Related Conditions Program with the central priority of expanding veteran access to novel HCV treatments and timely cure to ultimately prevent morbidity and mortality associated with HCV disease progression. This successful collaboration resulted in clinical resource funding to bolster access to HCV treatment through the deployment of CPS providers. This enterprise-wide initiative to expand clinical pharmacy services for unmet health care needs in HCV treatment resulted in 52 VA facilities submitting full-time employment equivalent (FTEE) funding requests totaling more than $10 million dollars. Facilities may have requested funding for 1 or more FTEEs. RESULTS: Facilities hired 47 CPS providers and 5 clinical pharmacy technicians. CPS providers in this project recorded 24,888 patient care encounters providing care for 9593 unique patients and initiated new HCV treatment for 1191 treatment-naïve patients. For an additional 8402 patients, the CPS provided HCV care activities such as evaluation and monitoring before, during, and after treatment. CPPO estimates that the same care delivered by nonpharmacist provider specialists (e.g., specialty physicians) cost an additional $936,535, or 48% more. CONCLUSION: The deployment of HCV CPS resulted in a significant number of new HCV patients being screened and treated within the VA system.

Many-Body Spectral Functions from Steady State Density Functional Theory.

We propose a scheme to extract the many-body spectral function of an interacting many-electron system from an equilibrium density functional theory (DFT) calculation. To this end we devise an ideal scanning tunneling microscope (STM) setup and employ the recently proposed steady-state DFT formalism (i-DFT) which allows one to calculate the steady current through a nanoscopic region coupled to two biased electrodes. In our setup, one of the electrodes serves as a probe ("STM tip"), which is weakly coupled to the system we want to measure. In the ideal STM limit of vanishing coupling to the tip, the system is restored to quasi-equilibrium and the normalized differential conductance yields the exact equilibrium many-body spectral function. Calculating this quantity from i-DFT, we derive an exact relation expressing the interacting spectral function in terms of the Kohn-Sham one. As illustrative examples, we apply our scheme to calculate the spectral functions of two nontrivial model systems, namely the single Anderson impurity model and the Constant Interaction Model.

Spin Control Induced by Molecular Charging in a Transport Junction.

The ability of molecules to maintain magnetic multistability in nanoscale-junctions will determine their role in downsizing spintronic devices. While spin-injection from ferromagnetic leads gives rise to magnetoresistance in metallic nanocontacts, nonmagnetic leads probing the magnetic states of the junction itself have been considered as an alternative. Extending this experimental approach to molecular junctions, which are sensitive to chemical parameters, we demonstrate that the electron affinity of a molecule decisively influences its spin transport. We use a scanning tunneling microscope to trap a meso-substituted iron porphyrin, putting the iron center in an environment that provides control of its charge and spin states. A large electron affinity of peripheral ligands is shown to enable switching of the molecular S = 1 ground state found at low electron density to S = 1/2 at high density, while lower affinity keeps the molecule inactive to spin-state transition. These results pave the way for spin control using chemical design and electrical means.

[Acute Liver Failure, Acute-On-Chronic Liver Failure, Hepatorenal Syndrome, Hepatopulmonary Syndrome and Portopulmonary Hypertension, Artificial Liver Support on the ICU]. / Akutes Leberversagen, akut-auf-chronisches Leberversagen, hepatorenales Syndrom, hepatopulmonales Syndrom und portopulmonale Hypertonie, Leberunterstützungsverfahren auf der Intensivstation.

Background Acute hepatic dysfunction in the form of acute liver failure (ALF) or acute-on-chronic liver failure (ACLF) is a disease with a high risk of mortality and requires interdisciplinary intensive care. Aim This article explains the nomenclature, pathophysiology, prognosis and possible treatment options of ALF and ACLF, including the possibilities of extracorporeal liver support therapy at the point of liver transplantation (LTx). Method Narrative review with a selective literature review and representative case studies. Results/Corner Points ALF and ACLF may have several causes and are associated with high mortality. The causes of ALF must be accurately diagnosed because targeted treatment options are available. Both ALF and ACLF may require a liver transplantation for the patient's survival. For ALF and ACLF there are different criteria for decision-making on liver transplantation and graft allocation. For extracorporeal liver support therapy, two methods have been established (MARS [molecuar adsorbent recirculating system] and FPSA [fractionated plasma separation and adsorption] Prometheus®). Both approaches may have the potential to increase the probability of survival of patients with ALF or ACLF. In some cases they can be used for bridging to liver transplantation, in individual cases also for primary poison elimination, e.g. after Amatoxin ingestion. Both methods are not suitable for long-term therapy. Conclusion Acute liver failure (ALF) and acute on chronic liver failure (ACLF) are serious diseases with a high risk of mortality. Affected patients should receive immediate interdisciplinary intensive care in a (tertiary) centre with the aim to clarify the cause of the disease as well as possible treatment options with respect to available extracorporeal liver support therapy and liver transplantation.

Shifting the Voltage Drop in Electron Transport Through a Single Molecule.

A Mn-porphyrin was contacted on Au(111) in a low-temperature scanning tunneling microscope (STM). Differential conductance spectra show a zero-bias resonance that is due to an underscreened Kondo effect according to many-body calculations. When the Mn center is contacted by the STM tip, the spectrum appears to invert along the voltage axis. A drastic change in the electrostatic potential of the molecule involving a small geometric relaxation is found to cause this observation.

The Kondo effect in ferromagnetic atomic contacts.

Iron, cobalt and nickel are archetypal ferromagnetic metals. In bulk, electronic conduction in these materials takes place mainly through the s and p electrons, whereas the magnetic moments are mostly in the narrow d-electron bands, where they tend to align. This general picture may change at the nanoscale because electrons at the surfaces of materials experience interactions that differ from those in the bulk. Here we show direct evidence for such changes: electronic transport in atomic-scale contacts of pure ferromagnets (iron, cobalt and nickel), despite their strong bulk ferromagnetism, unexpectedly reveal Kondo physics, that is, the screening of local magnetic moments by the conduction electrons below a characteristic temperature. The Kondo effect creates a sharp resonance at the Fermi energy, affecting the electrical properties of the system; this appears as a Fano-Kondo resonance in the conductance characteristics as observed in other artificial nanostructures. The study of hundreds of contacts shows material-dependent log-normal distributions of the resonance width that arise naturally from Kondo theory. These resonances broaden and disappear with increasing temperature, also as in standard Kondo systems. Our observations, supported by calculations, imply that coordination changes can significantly modify magnetism at the nanoscale. Therefore, in addition to standard micromagnetic physics, strong electronic correlations along with atomic-scale geometry need to be considered when investigating the magnetic properties of magnetic nanostructures.

Pre-Cycloplegic Exam Benefit of Photoscreening and Accommodation-Relaxing Skiascopy.

Background: Seeking a quick way to estimate refractions for challenging pediatric patients, we studied two non-contact methods with particular attention to accuracy and level of stress in uncovering cycloplegic hyperopia. Methods: Newly referred and follow-up pediatric eye patients had timed school bus accommodation-relaxing skiascopy (SBARS) and Plusoptix A12 (Px) photoscreener testing before cyclopentolate 1% confirmatory examinations. The ABCD ellipsoid univariate method based on relative blur and vector components was used to compare dry sphero-cylinder refraction estimates with cycloplegic. Receiver operating characteristic (ROC) curves were used to determine screening value. Results: Three compared refractions were attempted in 191 racially diverse children of whom 100 were age 0.2-3.9 years and 91 were 4 to 14 years. Plusoptix failed to yield a result in 21 and an additional 21 were interpreted as an excess sphere. Median spherical equivalent did not differ between Px and SBARS for 149 with Px readings but in hyperopic patients, Plusoptix uncovered 27% less hyperopia. The ellipsoid for SBARS of 0.8 was better than 2.4 for Plusoptix (Mann-Whitney p<0.001). Plusoptix was fastest (3-15 seconds) followed by SBARS (15-30 seconds) compared to 30-45 minutes for cycloplegic exam. Conclusion: Non-contact quick refractive methods enhanced confirmatory cycloplegic pediatric exam in high-risk pediatric patients.

Risk of Hepatitis B Reactivation in Patients Receiving Ibrutinib: The National Veterans Affairs Cohort.

Background: Ibrutinib has been a first-line treatment for chronic lymphocytic leukemia since 2014. Case reports of hepatitis B virus (HBV) reactivation after ibrutinib initiation have been presented. The association between the risk of HBV reactivation and ibrutinib initiation remains unclear. This nationwide study aimed to estimate the incidence of HBV reactivation after ibrutinib initiation. Method: This study included patients who received ibrutinib between 1 February 2014 and 31 October 2019. Possible reactivations were searched by (1) changes in HBV surface antigen or HBV DNA from no data or negative status to positive after ibrutinib initiation, (2) alanine aminotransferase levels that were at least 3 times the baseline value after ibrutinib initiation, and (3) new antiviral prescriptions against HBV after ibrutinib initiation. Individual chart reviews were conducted to identify HBV reactivation attributed to ibrutinib. The cumulative incidence of HBV reactivation was calculated. Results: A total 4130 patients were eligible during the study period. Of these, patients with negative HBV core antibody (anti-HBcAb; n = 1670) and patients who were taking antivirals against HBV (n = 60) were excluded. There were 2219 patients without anti-HBcAb testing results. Among the remaining 181 patients with positive anti-HBcAb, 7 HBV reactivations were directly attributable to ibrutinib treatment after chart review, for a 3.9% cumulative incidence. Conclusions: Our study revealed a low cumulative incidence of HBV reactivation after ibrutinib initiation among patients with previous anti-HBcAb positivity, indicating a moderate risk of HBV reactivation.

The yield of total body CT in the workup of fever of unknown origin in hospitalized medical patients.

INTRODUCTION: Total body computerized tomography (TBCT) is frequently used as a diagnostic tool for fever of unknown origin (FUO) workup instead of a recommended fluorodeoxyglucose positron emission tomography FDG-PET/CT. We have assessed the TBCT diagnostic yield on a large, unselected cohort of patients with FUO. METHODS: We performed a single-center retrospective cohort study, examining all patients hospitalized in internal medicine between 2012 and 2019 with a documented fever and three negative blood cultures who subsequently had a total-body CT performed. After manually reviewing, we included 408 who met the criteria of FUO. We defined a positive study as a scan that led to the documented final diagnosis. RESULTS: A total of 164 patients (40.2 %) had a positive TBCT result. The majority of positive CT findings were of infectious etiologies (58.5 %), followed by neoplasms (22.8 %) and inflammatory disorders (14.0 %), with the chest (43.9 %) and abdomen (29.8 %) most affected. Using a logistic regression model, a positive scan results were associated with an elevated CRP (p<0.001). Decision tree analysis showed that 55 % of scans of patients with an elevated CRP (>6 mg/dL), low hemoglobin and high leucocyte count (>18000/ml) were positive. Patients without an elevated CRP had a positive scan in only 26 % of tests, and those with also an elevated albumin (>4 gr/dL) and low CRP had positive scan in only 11 % of cases. CONCLUSIONS: TBCT has a clinically significant yield under specific clinical scenarios in medical patients with FUO- reaching 55 % in patients with an elevated CRP and leukocyte count and low hemoglobin. It is reasonable to proceed to TTBCT when FDG-PET/CT is unavailable and in well-defined clinical situations.

FDrisk: development of a validated risk assessment tool for Fabry disease utilizing electronic health record data.

Purpose: Fabry disease (FD) is a rare, X-linked, lysosomal storage disease characterized by great variability in clinical presentation and progressive multisystemic organ damage. Lack of awareness of FD and frequent misdiagnoses cause long diagnostic delays. To address the urgent need for earlier diagnosis, we created an online, risk-assessment scoring tool, the FDrisk, for predicting an individual's risk for FD and prompting diagnostic testing and clinical evaluation. Methods: Utilizing electronic health records, data were collected retrospectively from randomly selected, deidentified patients with FD treated at the Emory Lysosomal Storage Disease Center. Deidentified, negative controls were randomly selected from the Fabry Disease Diagnostic Testing and Education project database, a program within the American Association of Kidney Patients Center for Patient Education and Research. Diagnosis of FD was documented by evidence of a pathogenic variant in GLA and/or an abnormal level of leukocyte α-Gal A. Thirty characteristic clinical features of FD were initially identified and subsequently curated into 16 clinical covariates used as predictors for the risk of FD. An overall prediction model and two sex-specific prediction models were built. Two-hundred and sixty samples (130 cases, 130 controls) were used to train the risk prediction models. One-hundred and ninety-seven independent samples (30 cases, 167 controls) were used for testing model performance. Prediction accuracy was evaluated using a threshold of 0.5 to determine a predicted case vs. control. Results: The overall risk prediction model demonstrated 80% sensitivity, 83.8% specificity, and positive predictive value of 47.1%. The male model demonstrated 75% sensitivity, 95.8% specificity, and positive predictive value of 75%. The female model demonstrated 83.3% sensitivity, 81.3% specificity, and positive predictive value of 45.5%. Patients with risk scores at or above 50% are categorized as "at risk" for FD and should be sent for diagnostic testing. Conclusion: We have developed a statistical risk prediction model, the FDrisk, a validated, clinician-friendly, online, risk-assessment scoring tool for predicting an individual's risk for FD and prompting diagnostic testing and clinical evaluation. As an easily accessible, user-friendly scoring tool, we believe implementing the FDrisk will significantly decrease the time to diagnosis and allow earlier initiation of FD-specific therapy.