Light Chain Amyloidosis: Patient Experience Survey from the Amyloidosis Research Consortium

Improving care for systemic light-chain amyloidosis patients: is a multidisciplinary approach best?

INTRODUCTION

Light chain (AL) amyloidosis is a rare and complex disease which can affect various systems of the body. In common with many rare and multisystemic diseases, the breadth of diagnostic, clinical, and supportive expertise required to care for such patients is best met by a multidisciplinary team.

AREAS COVERED

We outline different phases of the patients' journey, including diagnosis, staging, treatment, and response assessment, to highlight common clinical issues best resolved by a multidisciplinary approach.

EXPERT OPINION

To extend the benefit of multidisciplinary care to the majority of patients with AL amyloidosis, innovative healthcare models such as telehealth and multisite multidisciplinary team meetings need to be implemented. The need for a multidisciplinary approach where such a wide array of healthcare skills is required also highlights the shortcomings of our current diagnostic and monitoring assays. Better access to diagnostic and subtyping assays is necessary. The ability to characterize and measure the causative amyloidogenic light chain as well as imaging techniques to accurately diagnose and monitor response to therapy is also needed and is currently an area of research focus.

Nuclear imaging techniques for cardiac amyloidosis

PURPOSE OF REVIEW

Cardiac amyloidosis is a condition marked by the misfolding of precursor proteins into insoluble amyloid fibrils, leading to restrictive cardiomyopathy and heart failure symptoms. This review discusses advancements in nuclear imaging techniques that enhance the diagnosis and guide the management of cardiac amyloidosis, addressing the critical need for early and accurate detection in clinical practice.

RECENT FINDINGS

Recent studies and guidelines emphasizes the pivotal role of nuclear imaging techniques in diagnosing cardiac amyloidosis. Cardiac scintigraphy, using bone-avid tracers like 99mTc-PYP, 99mTc-DPD, and 99mTc-HMDP, is instrumental in distinguishing between transthyretin amyloidosis and light chain amyloidosis. PET, with tracers such as 11C-Pittsburgh Compound B (11C-PiB) and 18F-Florbetapir, offers significant potential in measuring amyloid burden and monitoring disease progression, providing detailed insights into the myocardial involvement.

SUMMARY

The advancements in nuclear imaging techniques significantly impact the management of cardiac amyloidosis. These methods allow for a more accurate diagnosis, detailed assessment of disease extent, and better differentiation between amyloidosis types, which are crucial for tailoring treatment approaches. The integration of these techniques into clinical practice is essential for improving patient outcomes and advancing research in cardiac amyloidosis.

Monoclonal Gammopathy of Clinical Significance (MGCS) and Related Disorders: A Review and the Role of Imaging

The term monoclonal gammopathy of clinical significance (MGCS) refers to a group of symptomatic monoclonal gammopathies that do not meet the diagnostic criteria for malignant plasma cell disorders, such as multiple myeloma or Waldenström macroglobulinemia. These symptoms are attributable to the paraneoplastic effects of monoclonal immunoglobulins that occur through diverse mechanisms. The presence of symptoms distinguishes MGCS from monoclonal gammopathy of undetermined significance, which lacks significant symptomatic presentation. The presentations of MGCS are manifold, adding to the diagnostic challenge. Clinical suspicion is key for accurate and timely diagnosis. Radiologic imaging can provide pivotal information to guide the diagnosis. In this review, we discuss MGCS from a radiology perspective and highlight pertinent imaging features associated with the disorders.

Autologous stem cell transplantation in AL amyloidosis: Muddy waters

Immunoglobulin light chain (AL) amyloidosis is a malignant plasma cell dyscrasia causing multi-organ morbidity. High dose melphalan and autologous stem cell transplantation (ASCT) is a preferred consolidation approach and is safe with improved patient selection criteria. With the advent of bortezomib and daratumumab based induction therapy, nearly all patients can achieve deep hematological responses but follow up for daratumumab based induction is short. Consequently, the traditional approach of induction followed by ASCT is called into question. Given the multi-organ involvement of AL, endpoints beyond depth of response and hematological progression free survival (PFS) are important. Major organ dysfunction PFS (MOD-PFS) adds to PFS and is a composite endpoint of PFS, renal and cardiac organ progression, and overall survival. It is currently unknown which consolidative approach (ASCT or non-ASCT) will generate improved outcomes across the MOD-PFS spectrum a question the recently opened S2213 trial will attempt to answer.

Pathway for Development and Validation of Multi-domain Endpoints for Amyloid Light Chain (AL) Amyloidosis

Immunoglobin light chain (AL) amyloidosis is a rare disease in which a plasma cell dyscrasia leads to deposition of insoluble amyloid fibrils in multiple organs. To facilitate development of new therapies for this heterogenous disease, a public-private partnership was formed between the nonprofit Amyloidosis Research Consortium and the US Food and Drug Administration Center for Drug Evaluation and Research. In 2020, the Amyloidosis Forum launched an initiative to identify clinical trial endpoints and analytic strategies across affected organ systems and life impacts via specialized working groups. This review summarizes the proceedings of the Statistical Group and proposes a pathway for development and validation of multi-domain endpoints (MDEs) for potential use in AL amyloidosis clinical trials. Specifically, drawing on candidate domain-specific endpoints recommended by each organ-specific working group, different approaches to constructing MDEs were considered. Future studies were identified to assess the validity, meaningfulness and performance of MDEs through use of natural history and clinical trial data. Ultimately, for drug development, the context of use in a regulatory evaluation, the specific patient population, and the investigational therapeutic mechanism should drive selection of appropriate endpoints. MDEs for AL amyloidosis, once developed and validated, will provide important options for advancing patient-focused drug development in this multi-system disease.

Timing and co-occurrence of symptoms prior to a diagnosis of light chain (AL) amyloidosis

It is well-established that most patients with systemic light chain (AL) amyloidosis have multi-organ involvement and are often diagnosed after a lag period of increasing symptoms. We leverage electronic health record (EHR) data from the TriNetX research network to describe the incidence, timing, and co-occurrence of precursor conditions of interests in a cohort of AL amyloidosis patients identified between October 2015-December 2020. Nineteen precursor diagnoses of interest representing features of AL amyloidosis were identified using ICD codes up to 36 months prior to AL amyloidosis diagnosis. Among 1,401 patients with at least 36 months of EHR data prior to AL amyloidosis diagnosis, 46% were females, 16% were non-Hispanic Black, and 6% were Hispanic. The median age was 71 (range, 21-91) years. The median number of precursor diagnoses was 5 with dyspnea and fatigue being the most prevalent. The time from the first occurrence of a precursor to AL diagnosis ranged from 3.2 to 21.4 months. Analyses of pairwise co-occurrence of specific diagnoses indicated a high association (Cole's coefficient >0.6) among the examined precursor diagnoses. These findings provide novel information about the timing and co-occurrence of key precursor conditions and could be used to develop algorithms for early identification of AL amyloidosis.

Artificial Intelligence Assists in the Early Identification of Cardiac Amyloidosis

A 69-year-old female presented with symptomatic atrial fibrillation. Cardiac amyloidosis was suspected due to an artificial intelligence clinical tool applied to the presenting electrocardiogram predicting a high probability for amyloidosis, and the subsequent unexpected finding of left atrial appendage thrombus reinforced this clinical suspicion. This facilitated an early diagnosis by the biopsy of AL cardiac amyloidosis and the prompt initiation of targeted therapy. This case highlights the utilization of an AI clinical tool and its impact on clinical care, particularly for the early detection of a rare and difficult to diagnose condition where early therapy is critical.

Single German centre experience with patient journey and care-relevant needs in amyloidosis: The German AMY-NEEDS research and care program

BACKGROUND

Amyloidosis is a rare multi-system disorder associated with frequently delayed diagnosis, enormous disease burden and psychosocial distress.

METHODS

Systematic assessment of needs was performed by a subtype-spanning questionnaire-based survey within the AMY-NEEDS research and care program.

RESULTS

118 patients with proven amyloidosis (62.7% ATTR, 22.0% AL, 15.3% other forms) were included in August 2020 until February 2021 (mean age 71.2 ±11.3 years; 30% women). The median diagnostic delay between onset of symptoms and diagnosis was 9.0 (range: 2.5; 33.0) months. Local health care providers (HCPs) play a central role on the way to diagnosis. Diagnosis itself typically requires a clinical but not necessarily a university setting. In the treatment phase, the focus moves to the amyloidosis centre as primary contact and coordinator, with general practitioners (GPs) acting predominantly as a contact point in crisis and link to additional services. About half of patients reported impaired quality of life and one third suffering from anxiety and depressed mood, respectively. The majority of patients talk about their concerns with close caregivers and local HCPs. Advance care planning is a relevant, yet insufficiently met need.

CONCLUSION

The journey of patients with amyloidotic disease, their contact partners and needs at different stages were characterized in detail within the German health care system. An amyloidosis-specific care concept has to master the multitude of interfaces connecting the numerous treatment providers involved with the amyloidosis centre and GPs as key players. Telemedical approaches could be a promising and well-accepted option allowing optimal coordination and communication.

Healthcare Resource Utilization and Cost-of-Illness in Systemic Light Chain (AL) Amyloidosis in Europe: Results From the Real-World, Retrospective EMN23 Study

OBJECTIVES

To report healthcare resource utilization (HCRU) and safety outcomes in systemic light chain (AL) amyloidosis from the EMN23 study.

MATERIALS AND METHODS

The retrospective, observational, multinational EMN23 study included 4,480 patients initiating first-line treatment for AL amyloidosis in 2004-2018 and assessed, among other objectives, HCRU and safety outcomes. HCRU included hospitalizations, examinations, and dialysis; safety included serious adverse events (SAEs) and adverse events of special interest (AESIs). Data were descriptively analyzed by select prognostic factors (e.g., cardiac staging by Mayo2004/European) for 2004-2010 and 2011-2018. A cost-of-illness analysis was conducted for the UK and Spain.

RESULTS

HCRU/safety and dialysis data were extracted for 674 and 774 patients, respectively. Of patients with assessed cardiac stage (2004-2010: 159; 2011-2018: 387), 67.9% and 61.0% had ≥ 1 hospitalization, 56.0% and 51.4% had ≥ 1 SAE, and 31.4% and 28.9% had ≥ 1 AESI across all cardiac stages in 2004-2010 and 2011-2018, respectively. The per-patient-per-year length of hospitalization increased with disease severity (cardiac stage). Of patients with dialysis data (2004-2010: 176; 2011-2018: 453), 23.9% and 14.8% had ≥ 1 dialysis session across all cardiac stages in 2004-2010 and 2011-2018, respectively. The annual cost-of-illness was estimated at €40,961,066 and €31,904,386 for the UK and Spain, respectively; dialysis accounted for ∼28% (UK) and ∼35% (Spain) of the total AL amyloidosis costs.

CONCLUSIONS

EMN23 showed that the burden of AL amyloidosis is substantial, highlighting the need for early disease diagnosis and effective treatments targeting the underlying pathology.

How Artificial Intelligence Can Enhance the Diagnosis of Cardiac Amyloidosis: A Review of Recent Advances and Challenges

Cardiac amyloidosis (CA) is an underdiagnosed form of infiltrative cardiomyopathy caused by abnormal amyloid fibrils deposited extracellularly in the myocardium and cardiac structures. There can be high variability in its clinical manifestations, and diagnosing CA requires expertise and often thorough evaluation; as such, the diagnosis of CA can be challenging and is often delayed. The application of artificial intelligence (AI) to different diagnostic modalities is rapidly expanding and transforming cardiovascular medicine. Advanced AI methods such as deep-learning convolutional neural networks (CNNs) may enhance the diagnostic process for CA by identifying patients at higher risk and potentially expediting the diagnosis of CA. In this review, we summarize the current state of AI applications to different diagnostic modalities used for the evaluation of CA, including their diagnostic and prognostic potential, and current challenges and limitations.

Chronic underlying gastrointestinal amyloidosis was revealed by cardiac echography: a case report from Syria

Introduction and importance

Amyloidosis is an infiltrative disease caused by the deposition of abnormal proteins. While cardiac amyloidosis is relatively common, gastrointestinal (GI) tract involvement is less frequent. In this case, the authors report a delayed diagnosis of systemic amyloidosis presenting mainly with digestive symptoms.

Case presentation

An 81-year-old male presented with the complaint of persistent diarrhoea for over a year and the progressive development of edemas during the last 4 months. Echocardiogram findings revealed the presence of the characteristic sparkling sign. The diagnosis of amyloidosis was confirmed by histopathological biopsies taken from the duodenum. Serum electrophoresis findings strongly suggested the possibility of plasma cell dyscrasia.

Clinical discussion

What distinguishes this case is that the suspicion of amyloidosis as the underlying cause of the diarrhoea did not arise until an incidental echocardiogram revealed cardiac hypertrophy and a sparkling appearance.

Conclusion

This case reminds us to consider amyloidosis as a possible underlying cause for unexplained gastrointestinal symptoms such as diarrhoea, especially in bad economic situations where the diagnosis of rare diseases may be delayed.

Speckle tracking echocardiography in plasma cell disorders: The role of advanced imaging in the early diagnosis of AL systemic cardiac amyloidosis

INTRODUCTION

Amyloid light-chain amyloidosis is a rare condition characterized by the abnormal production of immunoglobulin light chain that misshape and form amyloid fibrils. Over time, these amyloid deposits can accumulate slowly, causing dysfunction in organs and tissues. Early identification is crucial to ensure optimal treatment. We aim to identify a better marker of cardiac amyloidosis, using advanced echocardiography, to improve diagnosis and the timing of available treatments.

MATERIALS AND METHODS

108 consecutive hematological patients (32, 30% female and 76, 70% male) with a plasma cell disorder referred to our Cardiological center underwent ECG, first and second-level echocardiography (Speckle Tracking) and complete biochemical profile. The best predictors of ALCA (AUC ≥ 0.8) were included in a further analysis stratified by AL score.

RESULTS

At ROC analysis, the best bio-humoral predictors for the diagnosis of ALCA were Nt-pro-BNP (AUC: 0.97; p < 0.01) and Hs-Tn (AUC: 0.87; p < 0.01). Regarding echocardiography, the best diagnostic predictors were left atrial stiffness (LAS) (AUC: 0.83; p < 0.01) for the left atrium; free wall thickness for the right ventricle (AUC: 0.82; <0.01); left ventricular global longitudinal strain (LVGLS) (AUC: 0.92; p < 0.01) and LVMi (AUC 0.80; p < 0.001) for the left ventricle; and AL-score (AUC 0.83 p < 0.01). In patients with AL-SCORE < 1, LAS (AUC 0.86 vs AUC 0.79), LVGLS (AUC 0.92 vs AUC 0.86) and LV mass (AUC 0.91 vs AUC 0.72) had better diagnostic accuracy than patients with higher AL-score (AL SCORE ≥ 1).

CONCLUSION

Multi-parametric imaging approach with LVGLS and LAS may be helpful for detecting early cardiac involvement in AL amyloidosis.

Needs of amyloidosis patients and their care providers: design & first results of the AMY-NEEDS research and care program

BACKGROUND

Amyloidosis represents a rare yet heterogeneous multi-system disorder associated with a grave prognosis and an enormous psycho-emotional strain on patients, relatives, and caregivers. We here present the overall study design and first results of AMY-NEEDS, a research program aiming to systematically assess the needs of patients suffering from amyloidosis, their relatives and health care professionals (HCPs), and develop an amyloidosis-specific care approach.

METHODS

AMY-NEEDS uses a mixed-methods approach including focus groups (step 1), a questionnaire-based broad evaluation within the local amyloidosis patient collective (step 2), and the development of a needs-adapted care concept (step 3).

RESULTS

Seven patients, six relatives and five HCPs participated in the focus groups (step 1). At the time of diagnosis, patients expressed the need of a smooth diagnostic process, possibly enhanced through improved awareness and better education of local HCPs. There was a strong wish to receive well-founded information and comprehensive support including companionship during medical visits, experience the feeling of being understood, find trust in that "everything possible" is being done, and have effortless access to centre staff. In the course of the disease, patients favoured that the specialized centre should manage treatment coordination, monitoring and psychosocial support. The interface between centre and local HCPs was regarded of particular importance, requiring further investigation into its optimal design.

CONCLUSIONS

Patients with amyloidosis express particular needs that should appropriately be considered in specifically tailored care concepts.

Establishment of a Comprehensive Cardiac Amyloidosis Center in a Community Hospital Setting

Cardiac amyloidosis is a great masquerader that often results in misdiagnosis of this condition. Early clinical recognition is crucial for timely therapeutic interventions to improve survival in patients with cardiac amyloidosis. Currently, Food and Drug Administration (FDA)-approved medications work best if started early in the disease. Thus, to increase identification, disease awareness, expertise in diagnostic techniques, and a multidisciplinary team approach is essential. The majority of the patients (~90%) in the United States are treated in community hospitals, thus, it would be helpful for these hospitals to have their own designated, comprehensive cardiac amyloidosis center to provide care to the patients who are widespread in the community. Most of these patients are elderly, and it is difficult for these patients to travel long distances to academic amyloid centers. Our manuscript aims to provide a path to the development of cardiac amyloid centers at community hospitals.

Timing and co-occurrence of symptoms prior to a diagnosis of light chain (AL) amyloidosis

It is well-established that light chain (AL) amyloidosis patients have multi-organ involvement and are often diagnosed after a lag period of increasing symptoms. We leverage electronic health record (EHR) data from the TriNetX research network to describe the incidence, timing, and co-occurrence of precursor conditions of interests in a cohort of AL amyloidosis patients identified between October 2015-December 2020. Nineteen precursor diagnoses of interest representing features of AL amyloidosis were identified using ICD codes up to 36 months prior to AL amyloidosis diagnosis. Among 1,401 patients with at least 36 months of EHR data prior to AL amyloidosis diagnosis, 46% were females, 16% were non-Hispanic Black, and 6% were Hispanic. The median age was 71 (range, 21-91) years. The median number of precursor diagnoses was 5 with dyspnea and fatigue being the most prevalent. The time from the first occurrence of a precursor to AL diagnosis ranged from 3.2 to 21.4 months. Analyses of pairwise co-occurrence of specific diagnoses indicated a high association (Cole's coefficient > 0.6) among the examined precursor diagnoses. These findings provide novel information about the timing and co-occurrence of key precursor conditions and could be used to develop algorithms for early identification of AL amyloidosis.

Amyloid consults do not have to be vexing

Diagnosing amyloidosis can be challenging due to its clinical heterogeneity, need for multiple specialists to make a diagnosis, and lack of a single diagnostic test for the disease. Patients are often diagnosed late, in advanced stage, and after exhibiting multiple symptoms and signs for a long period. It is important to develop a clinical suspicion of amyloidosis, particularly in those with multisystemic symptoms and high-risk patient populations such as those with precursor hematologic conditions. A systematic approach to the workup of suspected amyloidosis is key, including a comprehensive clinical assessment, laboratory tests to assess organ involvement, advanced imaging studies, screening for plasma cell disorder, and tissue biopsy when necessary. After making a diagnosis of amyloidosis, accurate typing of amyloid deposits, differentiating between localized and systemic amyloidosis, and appropriately staging the disease is important. Early diagnosis is crucial for improving patient outcomes and quality of life in light chain amyloidosis.

Assessing the prognostic utility of hematologic response for overall survival in patients with newly diagnosed AL amyloidosis: results of a meta-analysis

OBJECTIVES

Amyloid light-chain (AL) amyloidosis is a rare disease characterized by amyloid fibril deposits made up of toxic light chains causing progressive organ dysfunction and death. Recent studies suggest that hematologic response may be an important prognostic indicator of overall survival (OS) in AL amyloidosis. The aim of this study was to evaluate the trial-level association between hematologic complete response (CR) or very good partial response or better (≥ VGPR) and OS in newly diagnosed patients.

METHODS

Studies were identified via systematic literature review. Pooled effect estimates were generated by a random-effects model.

RESULTS

Nine observational studies reporting hematologic CR or ≥VGPR and OS hazard ratios (HRs) were included in the meta-analysis. Achieving hematologic CR was associated with improved OS (HR, 0.21; 95% confidence interval [CI] 0.13-0.34). Achieving ≥ VGPR was also associated with improved OS (HR 0.21; 95% CI 0.17-0.26). Results of a sensitivity analysis excluding one outlier study revealed no heterogeneity and a better overall HR estimate. Potential limitations of this meta-analysis include the small number of eligible studies (consistent with the rarity of the disease) and inconsistencies in reporting of results.

CONCLUSIONS

Overall, our findings support the use of deep hematologic response (CR or ≥VGPR) as a clinical trial endpoint in newly diagnosed AL amyloidosis. This study provides evidence that early hematologic response is a strong patient-level surrogate for long-term OS in patients with AL amyloidosis receiving frontline therapy. Structured data collection of depth of response in future trials will further strengthen these observations.

Patient Journey Toward a Diagnosis of Light Chain Amyloidosis in a National Sample: Cross-Sectional Web-Based Study

BACKGROUND

Systemic light chain (AL) amyloidosis is a rare and multisystem disease associated with increased morbidity and a poor prognosis. Delayed diagnoses are common due to the heterogeneity of the symptoms. However, real-world insights from Chinese patients with AL amyloidosis have not been investigated.

OBJECTIVE

This study aimed to describe the journey to an AL amyloidosis diagnosis and to build an in-depth understanding of the diagnostic process from the perspective of both clinicians and patients to obtain a correct and timely diagnosis.

METHODS

Publicly available disease-related content from social media platforms between January 2008 and April 2021 was searched. After performing data collection steps with a machine model, a series of disease-related posts were extracted. Natural language processing was used to identify the relevance of variables, followed by further manual evaluation and analysis.

RESULTS

A total of 2204 valid posts related to AL amyloidosis were included in this study, of which 1968 were posted on haodf.com. Of these posts, 1284 were posted by men (median age 57, IQR 46-67 years); 1459 posts mentioned renal-related symptoms, followed by heart (n=833), liver (n=491), and stomach (n=368) symptoms. Furthermore, 1502 posts mentioned symptoms related to 2 or more organs. Symptoms for AL amyloidosis most frequently mentioned by suspected patients were nonspecific weakness (n=252), edema (n=196), hypertrophy (n=168), and swelling (n=140). Multiple physician visits were common, and nephrologists (n=265) and hematologists (n=214) were the most frequently visited specialists by suspected patients for initial consultation. Additionally, interhospital referrals were also commonly seen, centralizing in tertiary hospitals.

CONCLUSIONS

Chinese patients with AL amyloidosis experienced referrals during their journey toward accurate diagnosis. Increasing awareness of the disease and early referral to a specialized center with expertise may reduce delayed diagnosis and improve patient management.

Peripheral Nervous, Hepatic, and Gastrointestinal Endpoints for AL Amyloidosis Clinical Trials: Report from the Amyloidosis Forum Multi-organ System Working Group

Systemic immunoglobulin light chain (AL) amyloidosis is a heterogeneous rare disease driven by a destructive monoclonal gammopathy and typified by misfolded immunoglobulin light and/or heavy chains which aggregate and deposit in organs as insoluble amyloid fibrils. Disease heterogeneity is driven by the degree of multi-systemic involvement; cardiac, renal, neurological, and gastrointestinal (GI) systems are affected to varying degrees in different patients. While prognosis is primarily driven by hematologic response to treatment and outcomes associated with cardiac events and overall survival, the involvement of the peripheral nervous, hepatic, and GI systems can also have a significant impact on patients. The Amyloidosis Forum ( https://amyloidosisforum.org ) is a public-private partnership between the nonprofit Amyloidosis Research Consortium ( www.arci.org ) and the US Food and Drug Administration (FDA) Center for Drug Evaluation and Research formed to advance drug development for the treatment of systemic amyloid disorders. A series of virtual workshops focused on the development of novel, patient-relevant endpoint components and analytical strategies for clinical trials in AL amyloidosis. This review summarizes the proceedings and recommendations of the Multi-Systemic Working Group which identified, reviewed, and prioritized endpoints relevant to the impacts of AL amyloidosis on the peripheral nervous, hepatic, and GI systems. The Working Group comprised amyloidosis experts, patient representatives, statisticians, and representatives from the FDA, Medicines and Healthcare products Regulatory Agency (MHRA), and pharmaceutical companies. Prioritized neuropathy/autonomic endpoints included a modified form of the Neuropathy Impairment Score (NIS + 7) and the Composite Autonomic Symptom Score (COMPASS-31), respectively. Alkaline phosphatase was identified as the most relevant indicator of liver involvement and disease progression. Following extensive review of potential GI endpoints, the Working Group identified multiple exploratory endpoints. These recommended components will be further explored through evaluation of clinical trial datasets and possible integration into composite endpoint analysis.

Light-chain cardiac amyloidosis for the non-expert: pearls and pitfalls

Cardiac amyloidosis (CA) is an uncommon, progressive, and fatal disease; the two main forms that can affect the heart are transthyretin CA and light chain CA (AL-CA). AL-CA is a medical urgency for which a diagnostic delay can be catastrophic for patients' outcome. In this manuscript, we focus on the pearls and pitfalls that are relevant to achieve a correct diagnosis and to avoid diagnostic and therapeutical delays. Through the aid of three unfortunate clinical cases, some fundamental diagnostic aspects are addressed, including the following: first, a negative bone scintigraphy does not exclude CA, with patients with AL-CA frequently showing no or mild cardiac uptake, and its execution should not delay hematological tests; second, fat pad biopsy does not have a 100% sensitivity for AL amyloidosis and, if negative, further investigations should be performed, particularly if the pre-test probability is high. Third, Congo Red staining is not sufficient to reach a definitive diagnosis and amyloid fibrils typing with mass spectrometry, immunohistochemistry, or immunoelectron microscopy is crucial. To achieve a timely and correct diagnosis, all the necessary investigations must be performed, always considering the yield and diagnostic accuracy of each examination.

Postdevelopment Performance and Validation of the Artificial Intelligence-Enhanced Electrocardiogram for Detection of Cardiac Amyloidosis

BACKGROUND

We have previously applied artificial intelligence (AI) to an electrocardiogram (ECG) to detect cardiac amyloidosis (CA).

OBJECTIVES

In this validation study, the authors observe the postdevelopment performance of the AI-enhanced ECG to detect CA with respect to multiple potential confounders.

METHODS

Amyloid patients diagnosed after algorithm development (June 2019-January 2022) with a 12-lead ECG were identified (n = 440) and were required to have CA. A 15:1 age- and sex-matched control group was identified (n = 6,600). Area under the receiver operating characteristic (AUC) was determined for the cohort and subgroups.

RESULTS

The average age was 70.4 ± 10.3 years, 25.0% were female, and most patients were White (91.3%). In this validation, the AI-ECG for amyloidosis had an AUC of 0.84 (95% CI: 0.82-0.86) for the overall cohort and between amyloid subtypes, which is a slight decrease from the original study (AUC 0.91). White, Black, and patients of "other" races had similar algorithm performance (AUC >0.81) with a decreased performance for Hispanic patients (AUC 0.66). Algorithm performance shift over time was not observed. Low ECG voltage and infarct pattern exhibited high AUC (>0.90), while left ventricular hypertrophy and left bundle branch block demonstrated lesser performance (AUC 0.75 and 0.76, respectively).

CONCLUSIONS

The AI-ECG for the detection of CA maintained an overall strong performance with respect to patient age, sex, race, and amyloid subtype. Lower performance was noted in left bundle branch block, left ventricular hypertrophy, and ethnically diverse populations emphasizing the need for subgroup-specific validation efforts.

Factors affecting the accuracy of amyloidosis identification and referral to a specialty centre

OBJECTIVE

Diagnostic algorithms for amyloidosis have evolved over the past decade, particularly with the incorporation of imaging-based techniques to detect amyloid cardiomyopathy. We sought to identify the key sources of amyloidosis misidentification in the community, which lead to false positive referrals to a tertiary centre.

METHODS

We conducted a retrospective review of all referrals to the Amyloidosis Centre from 2010 to 2021 and identified cases lacking amyloid pathology upon final adjudication after extensive assessment at the centre. Factors for false positive referrals were examined.

RESULTS

Among 2409 referrals of suspected amyloidosis, 147 (6%) demonstrated an absence of amyloid pathology. This percentage increased over time from 4% in 2010 to 13% in 2021. False positive referrals consisted of more people of colour. The most frequent source of inaccuracy was the erroneous staining of tissue specimens with Congo red, followed by suggestive findings on cardiac imaging. In recent years, misinterpretation of 99mtechnetium- pyrophosphate scintigraphy emerged as a major source of false positive referrals.

CONCLUSION

Recognising these potential sources of diagnostic error in the workup of amyloidosis can improve patient care. Referral to a centre of excellence for amyloidosis helps confirm an accurate diagnosis and avoid mistreatment.

Diagnosis and referral of patients with AL amyloidosis in Portugal: results from a Delphi panel

Light chain amyloidosis (AL) is a complex disorder defined by the extracellular deposition of insoluble amyloid fibrils formed by intact or fragmented immunoglobulin light chains, leading to cell dysfunction, rapid organ deterioration, and, ultimately, death. Although the clinical presentation of AL is directly connected to organ involvement, signs and symptoms of AL are frequently nonspecific, misinterpreted, and late recognized. Thus, an early diagnosis combined with effective therapies to cease disease progression and rescue organ function is essential. The aim of this study was to assess the knowledge and characterize the current clinical practice regarding AL diagnosis and referral among Portuguese physicians. A Delphi-like panel (one round only) with a group of national experts from different medical specialties (cardiology, hematology, internal medicine, nephrology, and neurology) was carried out online, in which 30 statements were classified using a 4-point Likert scale. For each statement, the consensus level was set at 70% for "fully agree/disagree" and the majority level was defined as >70% in agreement or disagreement. Although the results suggest the existence of adequate general knowledge of AL amyloidosis, they also disclosed the necessity to raise awareness for this disease. Overall, this Delphi panel revealed a high lack of consensus regarding the diagnosis and early management of patients with AL among different specialties despite the qualified majority obtained in 26 statements. An optimized strategy for AL early diagnosis, transversal to several medical fields, is urgently needed. Moreover, referral centers with access to diagnostic technology and a network of diverse specialties should be established to foster an early diagnosis and better disease approach to boost the possibility of a better outcome for patients with AL.

The patient pathway in ATTR-CM in Greece and how to improve it: A multidisciplinary perspective

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underdiagnosed disease associated with high mortality rates and the patient journey is characterized by increased complexities. Accurate and timely diagnosis and prompt initiation of disease-modifying treatment constitute the contemporary unmet need in ATTR-CM. ATTR-CM diagnosis is characterized by considerable delays and high rates of misdiagnosis. The majority of patients present themselves to primary care physicians, internists, and cardiologists, and many have undergone repeated medical evaluations before an accurate diagnosis has been made. The disease is diagnosed mainly after the development of heart failure symptoms, reflecting a long course of missed opportunities before diagnosis and disease-modifying treatment initiation. Early referral to experienced centers ensures prompt diagnosis and therapy. Early diagnosis, better care coordination, acceleration of digital transformation and reference networks, encouragement of patient engagement, and implementation of rare disease registries are the key pillars to improve the ATTR-CM patient pathway and achieve important benefits in ATTR-CM outcomes.

British Society of Echocardiography guideline for the transthoracic echocardiographic assessment of cardiac amyloidosis

These guidelines form an update of the BSE guideline protocol for the assessment of restrictive cardiomyopathy (Knight et al. in Echo Res Prac, 2013). Since the original recommendations were conceived in 2013, there has been an exponential rise in the diagnosis of cardiac amyloidosis fuelled by increased clinician awareness, improvements in cardiovascular imaging as well as the availability of new and effective disease modifying therapies. The initial diagnosis of cardiac amyloidosis can be challenging and is often not clear-cut on the basis of echocardiography, which for most patients presenting with heart failure symptoms remains the first-line imaging test. The role of a specialist echocardiographer will be to raise the suspicion of cardiac amyloidosis when appropriate, but the formal diagnosis of amyloid sub-type invariably requires further downstream testing. This document seeks to provide a focused review of the literature on echocardiography in cardiac amyloidosis highlighting its important role in the diagnosis, prognosis and screening of at risk individuals, before concluding with a suggested minimum data set, for use as an aide memoire when reporting.

Prognosis of light chain amyloidosis: a multivariable analysis for survival prediction in patients with cardiac involvement proven by endomyocardial biopsy

BACKGROUND

Cardiac involvement is a main determinant of mortality in light chain (AL) amyloidosis but data on survival of patients with cardiac AL amyloidosis proven by endomyocardial biopsy (EMB) are sparse.

METHODS

This study analysed clinical, laboratory, electrocardiography and echocardiographic parameters for their prognostic value in the assessment of patients with AL amyloidosis and cardiac involvement. Patients with AL amyloidosis who had their first visit to the amyloidosis centre at the University Hospital Heidelberg between 2006 and 2017 (n=1628) were filtered for cardiac involvement proven by EMB. In the final cohort, mortality-associated markers were analysed by univariate and multivariable Cox regression. Cut-off values for each parameter were calculated using the survival time.

RESULTS

One-hundred and seventy-four patients could be identified. Median overall survival time was 1.5 years and median follow-up time was 5.2 years. At the end of the investigation period, 115 patients had died. In multivariable analysis, New York Heart Association-functional class >II (HR 1.65; 95% CI 1.09 to 2.50; p=0.019), left ventricular global longitudinal strain (HR 1.12; 95% CI 1.03 to 1.22; p=0.007), left ventricular end-systolic volume (HR 1.02; 95% CI 1.01 to 1.03; p=0.001), systolic pulmonary artery pressure (HR 0.98; 95% CI 0.96 to 0.99; p=0.027), N-terminal pro-B-type natriuretic peptide (HR 1.57; 95% CI 1.17 to 2.11; p=0.003) and difference in free light chains (HR 1.30; 95% CI 1.05 to 1.62; p=0.017) were independently predictive.

CONCLUSION

Among all patients with AL amyloidosis those with cardiac involvement represent a high-risk population with limited therapy options. Therefore, accurate risk stratification is necessary to identify cardiac amyloidosis patients with favourable prognosis. Incorporation of modern imaging techniques into existing or newly developed scoring systems is a promising option that might enable the implementation of risk-adapted therapeutic strategies.

Amyloidosis of the tongue: a rare case report

•This patient presented with clinical symptoms of tongue enlargement and stiffness. •AL amyloidosis requires a pathological biopsy for diagnosis. •Treatment involves chemotherapy and local surgical interventions. •Misdiagnosis or delayed diagnosis of AL amyloidosis is common.

Evaluating the Amyloidosis Speakers Bureau: the influence of amyloidosis patients' narratives on medical students' knowledge, attitudes, and behavioral intent

Background:  Amyloidosis is a complex multi-systemic disease. Lack of knowledge about amyloidosis and subsequent mis- or under-diagnosis are major obstacles to treatment, which result in life-threatening organ damage, morbidity, and mortality. Hence, the purpose of this study is to explore the effectiveness of amyloidosis patients' narratives on medical students. Methods:  The Amyloidosis Speakers Bureau (ASB) arranges for amyloidosis patients to speak about their diagnostic and treatment experiences with medical students. Using a randomized post-test only experiment, we compared the effectiveness of patients' narratives between two groups (treatment and control). Outcome measures included medical students' intent to actively communicate with patients, acquire knowledge about amyloidosis, and reconsider diagnoses when warranted. Results:  The treatment group (those who listened to an ASB patient speaker) had higher mean differences on all measures, including the desire to improve communication with patients, acquire and apply knowledge of amyloidosis, and willingness to reconsider diagnoses when symptoms are puzzling. Conclusions:  ASB patient educators widened awareness of an under-diagnosed disease. Listening to a patient's narrative was associated with positive attitudes toward communication with patients, interest in acquiring and applying knowledge of amyloidosis, and humility about diagnosis. Narrative and persuasion theory are used to explain this quantitative evidence of the power of patient narratives.

The flutemetamol analogue cyano-flutemetamol detects myocardial AL and ATTR amyloid deposits: a post-mortem histofluorescence analysis

BACKGROUND

[18F]flutemetamol is a PET radioligand used to image brain amyloid, but its detection of myocardial amyloid is not well-characterized. This histological study characterized binding of fluorescently labeled flutemetamol (cyano-flutemetamol) to amyloid deposits in myocardium.

METHODS

Myocardial tissue was obtained post-mortem from 29 subjects with cardiac amyloidosis including transthyretin wild-type (ATTRwt), hereditary/variant transthyretin (ATTRv) and immunoglobulin light-chain (AL) types, and from 10 cardiac amyloid-free controls. Most subjects had antemortem electrocardiography, echocardiography, SPECT and cardiac MRI. Cyano-flutemetamol labeling patterns and integrated density values were evaluated relative to fluorescent derivatives of Congo red (X-34) and Pittsburgh compound-B (cyano-PiB).

RESULTS

Cyano-flutemetamol labeling was not detectable in control subjects. In subjects with cardiac amyloidosis, cyano-flutemetamol labeling matched X-34- and cyano-PiB-labeled, and transthyretin- or lambda light chain-immunoreactive, amyloid deposits and was prevented by formic acid pre-treatment of myocardial sections. Cyano-flutemetamol mean fluorescence intensity, when adjusted for X-34 signal, was higher in the ATTRwt than the AL group. Cyano-flutemetamol integrated density correlated strongly with echocardiography measures of ventricular septal thickness and posterior wall thickness, and with heart mass.

CONCLUSION

The high selectivity of cyano-flutemetamol binding to myocardial amyloid supports the diagnostic utility of [18F]flutemetamol PET imaging in patients with ATTR and AL types of cardiac amyloidosis.

Clinical characteristics and prognosis of a Chinese cohort with systemic light chain amyloidosis: a single-center study

Light chain amyloidosis is a plasma cell dyscrasia characterized by deposition of misfolded amyloid fibrils in tissues, leading to multi-organ dysfunction. We retrospectively analyzed 335 patients (median age, 60 years) with systemic light chain amyloidosis in the First Hospital of Peking University from 2011 to 2021. Involved organs were the kidney (92.8%), heart (57.9%), liver (12.8%) and peripheral nervous system (6.3%). Chemotherapy was administered to 55.8% (187/335) of patients, among whom 94.7% received novel agent-based regimens. Hematologic response (≥ very good partial response) was achieved in 63.4% of patients who received chemotherapy. Only 18.2% of patients received autologous hematopoietic stem cell transplant (ASCT). Among transplant-eligible patients, the overall survival of ASCT recipients was better than those who received chemotherapy only. The median overall survival of the patients with light chain amyloidosis was 77.5 months. Estimated glomerular filtration rate and Mayo 2012 stage were independent prognostic factors for overall survival in multivariate analysis. Although the younger age and high ratio of renal involvement might contribute to the favorable prognosis of this cohort, the role of novel agents and ASCT is also discernible. This study will provide a comprehensive perspective on progress in treatment of light chain amyloidosis in China.

Health-Related Quality of Life Instruments for Clinical Trials in AL Amyloidosis: Report from the Amyloidosis Forum HRQOL Working Group

Systemic AL (light chain) amyloidosis is a rare protein misfolding disorder associated with plasma cell dyscrasia affecting various organs leading to organ dysfunction and failure. The Amyloidosis Forum is a public-private partnership between the Amyloidosis Research Consortium and the US Food and Drug Administration Center for Drug Evaluation and Research with the goal of accelerating the development of effective treatments for AL amyloidosis. In recognition of this goal, 6 individual working groups were formed to identify and/or provide recommendations related to various aspects of patient-relevant clinical trial endpoints. This review summarizes the methods, findings, and recommendations of the Health-Related Quality of Life (HRQOL) Working Group. The HRQOL Working Group sought to identify existing patient-reported outcome (PRO) assessments of HRQOL for use in clinical trials and practice deemed relevant across a broad spectrum of patients with AL amyloidosis. A systematic review of the AL amyloidosis literature identified 1) additional signs/symptoms not currently part of an existing conceptual model, and 2) relevant PRO instruments used to measure HRQOL. The Working Group mapped content from each identified instrument to areas of impact in the conceptual model to determine which instrument(s) provide coverage of relevant concepts. The SF-36v2^® Health Survey (SF-36v2; QualityMetric Incorporated, LLC) and Patient-Reported Outcomes Measurement Information System-29 Profile (PROMIS-29; HealthMeasures) were identified as instruments relevant to patients with AL amyloidosis. Existing evidence of reliability and validity was evaluated with a recommendation for future work focused on estimating clinically meaningful within-patient change thresholds for these instruments. For sponsors, the context of use-including specific research objectives, trial population, and investigational product under study-should inherently drive selection of the appropriate PRO instrument and endpoint definitions to detect meaningful change and enable patient-focused drug development.

Amyloidosis: a case series and review of the literature

BACKGROUND

Systemic amyloidosis is group of disorders characterized by the accumulation of insoluble proteins in tissues. The most common form of systemic amyloidosis is light chain amyloidosis, which results from the accumulation of misfolded immunoglobulins. The disease is progressive, with treatment targeted at the underlying plasma cell dyscrasia. Since essentially any organ system can be affected, the presentation is variable and delays in diagnosis are common. Given this diagnostic difficulty, we discuss four different manifestations of light chain amyloidosis.

CASE PRESENTATIONS

In this case series, we discuss four cases of light chain amyloidosis. These include cardiac, hepatic, and gastrointestinal as well as autonomic and peripheral nerve involvement with amyloidosis. The patients in our series are of Caucasian background and include a  69-year-old female, a 29-year-old female, a 68-year-old male, and a 70-year-old male, respectively. The case discussions highlight variability in presentation and diagnostic challenges.

CONCLUSIONS

Amyloidosis is a rare but serious disease that is often complicated by long delays in diagnosis. Morbidity and mortality can sometimes be limited if diagnosed earlier. We hope our real life cases will contribute to understanding and to early suspicion that can lead to early diagnosis and management.

Clinical Confirmation of Pan-Amyloid Reactivity of Radioiodinated Peptide 124I-p5+14 (AT-01) in Patients with Diverse Types of Systemic Amyloidosis Demonstrated by PET/CT Imaging

There are at least 20 distinct types of systemic amyloidosis, all of which result in the organ-compromising accumulation of extracellular amyloid deposits. Amyloidosis is challenging to diagnose due to the heterogeneity of the clinical presentation, yet early detection is critical for favorable patient outcomes. The ability to non-invasively and quantitatively detect amyloid throughout the body, even in at-risk populations, before clinical manifestation would be invaluable. To this end, a pan-amyloid-reactive peptide, p5+14, has been developed that is capable of binding all types of amyloid. Herein, we demonstrate the ex vivo pan-amyloid reactivity of p5+14 by using peptide histochemistry on animal and human tissue sections containing various types of amyloid. Furthermore, we present clinical evidence of pan-amyloid binding using iodine-124-labeled p5+14 in a cohort of patients with eight (n = 8) different types of systemic amyloidosis. These patients underwent PET/CT imaging as part of the first-in-human Phase 1/2 clinical trial evaluating this radiotracer (NCT03678259). The uptake of 124I-p5+14 was observed in abdominothoracic organs in patients with all types of amyloidosis evaluated and was consistent with the disease distribution described in the medical record and literature reports. On the other hand, the distribution in healthy subjects was consistent with radiotracer catabolism and clearance. The early and accurate diagnosis of amyloidosis remains challenging. These data support the utility of 124I-p5+14 for the diagnosis of varied types of systemic amyloidosis by PET/CT imaging.

Detection and Diagnosis of Cardiac Amyloidosis in Egypt

Cardiac amyloidosis is a life-threatening disease that occurs when amyloid proteins, most commonly immunoglobulin light chain or transthyretin, mutate or become unstable, misfold, deposit as amyloid fibrils, and accumulate in the myocardium. Early diagnosis of cardiac amyloidosis is hindered by insufficient awareness, specifically regarding clinical red flags and diagnostic pathways. Cardiac amyloidosis diagnosis comprises two important phases, clinical suspicion (phase one) followed by definitive diagnosis (phase two). Each phase is associated with specific clinical techniques. For example, clinical features, electrocardiography, echocardiography, and cardiac magnetic resonance imaging serve to raise suspicion of cardiac amyloidosis and facilitate early diagnosis, whereas laboratory tests (i.e., blood or urine electrophoresis with immunofixation), biopsy, scintigraphy-based nuclear imaging, and genetic testing provide a definitive diagnosis of cardiac amyloidosis. In Egypt, both the lack of cardiac amyloidosis awareness amongst healthcare providers and the unavailability of clinical expertise for the use of diagnostic techniques must be overcome to improve the prognosis of cardiac amyloidosis in the region. Previously published diagnostic algorithms for cardiac amyloidosis have amalgamated techniques that can raise clinical suspicions of cardiac amyloidosis with those that definitively diagnose cardiac amyloidosis. Though such algorithms have been successful in developed countries, diagnostic tools like echocardiography, scintigraphy, and cardiac magnetic resonance imaging are not ubiquitously available across Egyptian facilities. This review presents the current state of knowledge regarding cardiac amyloidosis in Egypt and outlines a new diagnostic algorithm which leverages regional nuclear imaging expertise. Importantly, the proposed diagnostic algorithm guides accurate amyloid-typing to mitigate misdiagnosis and erroneous treatment selection and improve the cardiac amyloidosis diagnostic accuracy in Egypt.

The management of light chain (AL) amyloidosis in Europe: clinical characteristics, treatment patterns, and efficacy outcomes between 2004 and 2018

Systemic light-chain (AL) amyloidosis is a rare and debilitating disease. Advances have been made in new treatments in recent years, yet real-world data on the management of the disease are scarce. EMN23 is a retrospective, observational study of patients who initiated first-line treatment in 2004-2018 in Europe, presenting the demographics, clinical characteristics, treatment patterns, and outcomes, from 4480 patients. Regimens based on bortezomib were the most frequently used as first-line therapy; only 6.2% of the patients received autologous stem cell transplant. Hematologic responses improved post-2010 (67.1% vs 55.6% pre-2010). The median overall survival (OS) was 48.8 (45.2-51.7) months; 51.4 (47.3-57.7) months pre-2010 and 46.7 (41.3-52.2) months post-2010. Early mortality was 13.4% and did not improve (11.4% vs 14.4% pre- and post-2010); furthermore, it remained high in patients with advanced cardiac disease (over 39% for stage IIIb). There was a significant improvement for stage IIIa (14.2 vs 30.7 months, p = 0.0170) but no improvement for stage IIIb patients (5.0 vs 4.5 months). This European real-world study of AL-amyloidosis emphasizes the unmet needs of early diagnosis, and the lack of improvement in survival outcomes of the frail stage IIIb population, despite the introduction of new therapies in recent years.

Atypical Presentation of Amyloidosis in a Female Patient with Muscle Weakness

Muscle involvement represents a well-recognized but rare manifestation of amyloidosis. Here, we report a 40-year-old female who presented with muscle weakness, musculoskeletal pain, and proteinuria, which was eventually diagnosed as myopathic amyloidosis based on muscle biopsy results. A multidisciplinary approach appears to be the cornerstone of the diagnostic work up for recognizing the unusual amyloid myopathy.

The Clinical Characteristics of Immunoglobulin Light Chain Amyloidosis in the Chinese Population: A Systematic Scoping Review

Immunoglobulin light chain (AL) amyloidosis is the most common type of systemic amyloidosis in China and is associated with increased morbidity and a poor prognosis. However, the clinical characteristics of Chinese patients with AL amyloidosis have not been systematically investigated. This scoping review aimed to summarize the available literature regarding the clinical characteristics of patients with AL amyloidosis and identify potential knowledge gaps. We searched three electronic databases from inception to 7 February 2021. PICOS (Patient, Intervention, Comparison, Outcome and Study) design structure was used to formulate the data extraction. All statistical calculations and analyses were performed with R (version 3.6.0). Sixty-seven articles with 5022 patients were included. Results suggest Chinese patients were younger (57 years) at the time of diagnosis when compared with other patient populations and were predominantly male (61.2%). The time interval from the onset of symptoms to diagnosis was between 6 and 12 months. It was found that 41.1% of Chinese patients with AL amyloidosis were diagnosed with an advanced stage III disease when diagnosed, and 20.2% had a concurrent disease. The most involved organs were the kidneys (84.3%) and the heart (62.5%). In conclusion, our study shows some similarities and differences with other studies on the clinical characteristics of Chinese patients with AL amyloidosis, including the age at diagnosis, Mayo stage, and organ involvement. However, a nationwide epidemiological investigation is still needed to provide a comprehensive overview of this patient population in China.

Systemic amyloidosis journey from diagnosis to outcomes: a twelve-year real-world experience of a single center in a middle-income country

BACKGROUND

Systemic amyloidosis is caused by the deposition of misfolded protein aggregates in tissues, leading to progressive organ dysfunction and death. Epidemiological studies originate predominantly from high-income countries, with few data from Latin America. Due to the non-specific clinical manifestations, diagnosing amyloidosis is often challenging and patients experience a long journey and delay in diagnosis. This study aimed to assess clinical and laboratory characteristics, the diagnostic journey, and outcomes of patients with biopsy-proven systemic amyloidosis diagnosed between 2009 and 2020 at a university referral center in a middle-income Latin American country. Patients´ medical records were retrospectively reviewed.

RESULTS

One hundred and forty-three patients were included. The median age at diagnosis was 60 years and 54% were male. Until the diagnosis, most of the patients (52%) were seen by at least 3 specialists, the main ones being: general practitioners (57%), nephrologists (45%), and cardiologists (38%). The most common manifestations were renal (54%) and cardiac (41%) disorders, and cachexia was seen in 36% of patients. In 72% of the cases, ≥ 2 biopsies were required until the final diagnosis. The median time from symptoms onset to diagnosis was 10.9 months, and most patients (75%) had ≥ 2 organs involved. The following subtypes were identified: AL (68%), ATTR (13%), AA (8%), AFib (4%), and inconclusive (7%). Median OS was 74.3 months in the non-AL subgroup and 18.5 months in AL. Among AL patients, those with advanced cardiac stage had the worst outcome [median OS 8.6 months versus 52.3 for stage III versus I-II, respectively (p < 0.001)]. AL subtype, cardiac involvement, and ECOG ≥ 2 were identified as independent risk factors for reduced survival.

CONCLUSIONS

Systemic amyloidosis is still an underdiagnosed condition and the delay in its recognition leads to poor outcomes. Medical education, better diagnostic tools, improvement in access to therapies, and establishment of referral centers may improve patient outcomes in middle-income countries.

Diagnostic amyloid light chain amyloidosis hospitalizations associated with high acuity and cost: analysis of the Premier Healthcare Database

Aim: Estimate the frequency and costs of diagnostic admissions among hospitalized patients with amyloid light chain (AL) amyloidosis. Materials & methods: This retrospective analysis used nationally representative hospital discharge data from 2017 to 2020 to report resource use and cost for hospitalizations during which AL amyloidosis was diagnosed. Results: Of 1341 admissions, 17.6% were diagnostic. Bone marrow (79.5%) and kidney (44.9%) biopsies were the most common qualifying biopsies. Diagnostic hospitalizations had longer length of stay (14.5 vs 8.4 days; p < 0.001) and higher cost ($40,052 [USD] vs $24,360; p < 0.001) than nondiagnostic ones. Conclusion: Diagnostic admissions are more likely to be urgent/emergent, require longer stays and have higher costs compared with hospitalizations in known AL amyloidosis patients. Improved diagnostic pathways toward early diagnosis are needed.

AL Amyloidosis for Cardiologists: Awareness, Diagnosis, and Future Prospects: JACC: CardioOncology State-of-the-Art Review

Amyloid light chain (AL) amyloidosis is a rare, debilitating, often fatal disease. Symptoms of cardiomyopathy are common presenting features, and patients often are referred to cardiologists. Cardiac amyloid infiltration is the leading predictor of death. However, the variable presentation and perceived rarity of the disease frequently lead to delay in suspecting amyloidosis as a cause of heart failure, leading to misdiagnoses and a marked delay in diagnosis, with devastating consequences for the patient. A median time from symptom onset to correct diagnosis of about 2 years is often too long when median survival from diagnosis for patients with AL amyloidosis and cardiomyopathy is 4 months to 2 years. The authors highlight the challenges to diagnosis, identify gaps in the current knowledge, and summarize novel treatments on the horizon to raise awareness about the critical need for early recognition of symptoms and diagnosis of AL amyloidosis aimed at accelerating treatment and improving outcomes for patients.

The diagnostic value of multiparameter cardiovascular magnetic resonance for early detection of light-chain amyloidosis from hypertrophic cardiomyopathy patients

Background

Early-stage amyloidosis of the heart is prone to be underdiagnosed or misdiagnosed, increasing the risk of early heart failure and even death of the patient. To ensure timely intervention for cardiac light-chain amyloidosis (AL CA), it is vital to develop an effective tool for early identification of the disease. Recently, multiparameter cardiovascular magnetic resonance (CMR) has been used as a comprehensive tool to assess myocardial tissue characterization. We aimed to investigate the difference in left ventricular (LV) strain, native T1, extracellular volume (ECV), and late gadolinium enhancement (LGE) between AL CA patients, hypertrophic cardiomyopathy patients (HCM), and healthy control subjects (HA). Moreover, we explored the value of multiparameter CMR for differential diagnosis of the early-stage AL CA patients from HCM patients, who shared similar imaging characteristics under LGE imaging.

Methods

A total of 38 AL CA patients, 16 HCM patients, and 17 HA people were prospectively recruited. All subjects underwent LGE imaging, Cine images, and T1 mapping on a 3T scanner. The LV LGE pattern was recorded as none, patchy or global. LV strain, native T1, and ECV were measured semi-automatically using dedicated CMR software. According to clinical and biochemical markers, all patients were classified as Mayo stage I/II and Mayo stage IIIa/IIIb. Univariable and multivariable logistic regression models were utilized to identify independent predictors of early-stage AL CA from HCM patients. Receiver operator characteristic (ROC) curve analysis and Youden’s test were done to determine the accuracy of multiparameter CMR in diagnosing Mayo stage I/II AL CA and establish a cut-off value.

Results

For Mayo stage I/II AL CA patients, the global longitudinal strain (GLS) absolute value (11.9 ± 3.0 vs. 9.5 ± 1.8, P < 0.001) and the global circumferential strain (GCS) absolute value (19.0 ± 3.6 vs. 9.5 ± 1.8, P < 0.001) were significantly higher than in HCM patients. The native T1 (1334.9 ± 49.9 vs. 1318.2 ± 32.4 ms, P < 0.0001) and ECV values (37.8 ± 5.7 vs. 31.3 ± 2.5%, P < 0.0001) were higher than that of HCM patients. In multiparameter CMR models, GCS (2.097, 95% CI: 1.292–3.403, P = 0.003), GLS (1.468, 95% CI: 1.078–1.998, P = 0.015), and ECV (0.727, 95% CI: 0.569–0.929, P = 0.011) were the significant variables for the discrimination of the early-stage AL CA patients from HCM patients. ROC curve analysis and Youden’s test were used on GCS, GLS, ECV, and pairwise parameters for differentiating between Mayo stage I/II AL CA and HCM patients, respectively. The combination of GLS, GCS, and ECV mapping could distinguish Mayo stage I/II AL amyloidosis patients from hypertrophic cardiomyopathy with excellent performance (AUC = 0.969, Youden index = 0.813).

Conclusion

In early-stage AL CA patients with atypical LGE, who had similar imaging features as HCM patients, ECV mapping, GCS, and GLS were correlated with the clinical classification of the patients. The combination of GCS, GLS, and ECV could differentiate early-stage AL CA from HCM patients. Multiparameter CMR has the potential to provide an effective and quantitative tool for the early diagnosis of myocardial amyloidosis.

Renal amyloidosis: a new time for a complete diagnosis

Amyloidoses are a group of disorders in which soluble proteins aggregate and deposit extracellularly in tissues as insoluble fibrils, causing organ dysfunction. Clinical management depends on the subtype of the protein deposited and the affected organs. Systemic amyloidosis may stem from anomalous proteins, such as immunoglobulin light chains or serum amyloid proteins in chronic inflammation or may arise from hereditary disorders. Hereditary amyloidosis consists of a group of rare conditions that do not respond to chemotherapy, hence the identification of the amyloid subtype is essential for diagnosis, prognosis, and treatment. The kidney is the organ most frequently involved in systemic amyloidosis. Renal amyloidosis is characterized by acellular pathologic Congo red-positive deposition of amyloid fibrils in glomeruli, vessels, and/or interstitium. This disease manifests with heavy proteinuria, nephrotic syndrome, and progression to end-stage kidney failure. In some situations, it is not possible to identify the amyloid subtype using immunodetection methods, so the diagnosis remains indeterminate. In cases where hereditary amyloidosis is suspected or cannot be excluded, genetic testing should be considered. Of note, laser microdissection/mass spectrometry is currently the gold standard for accurate diagnosis of amyloidosis, especially in inconclusive cases. This article reviews the clinical manifestations and the current diagnostic landscape of renal amyloidosis.

Cardiac AL amyloidosis presenting as recurrent dyspnoea in a patient with cancer: an important clinical clue to an early diagnosis

Cardiac amyloidosis (CA) is challenging to diagnose due to its non-specific clinical manifestations early in the disease process. We report the case of a patient who presented with dyspnoea, abdominal distension and leg swelling. Medical history was notable for hypertension, recurrent vulvar squamous cell carcinoma and polysubstance abuse. Over 1 year before the official diagnosis of CA, the patient had multiple hospital readmissions for dyspnoea. Our case illustrates the importance of having a high index of clinical suspicion for an early diagnosis of CA. Furthermore, it highlights the need to re-evaluate a presumed diagnosis when a patient's symptoms recur or do not respond to appropriate treatment and to consider the influence of social factors on diagnostic processes.

Impact of cardiac amyloidosis on outcomes of patients hospitalized with heart failure

BACKGROUND

Amyloidosis is a multi-systemic disease potentially leading to failure of affected organs. We aimed to investigate prevalence and prognostic implications of cardiac amyloidosis of any etiology on outcomes of hospitalized patients with heart failure (HF) in Germany.

METHODS

We analyzed data of the German nationwide inpatient sample (2005-2018) of patients hospitalized for HF (including myocarditis with HF and heart transplantation with HF). HF patients with amyloidosis (defined as cardiac amyloidosis [CA]) were compared with those HF patients without amyloidosis and impact of CA on outcomes was assessed.

RESULTS

During this fourteen-year observational period 5,478,835 hospitalizations for HF were analyzed. Amyloidosis was coded in 5,407 HF patients (0.1%). CA prevalence was 1.87 hospitalizations per 100,000 German population. CA patients were younger (75.0[IQR 67.0-80.0]vs.79.0[72.0-85.0]years, p < 0.001), predominantly male (68.9%) and had a higher prevalence of cancer (14.8% vs. 3.6%, p < 0.001). Adverse in-hospital events including necessity of transfusions of blood constituents (7.1% vs. 5.4%, p < 0.001) and cardio-pulmonary resuscitation (CPR, 2.7% vs. 1.4%; p < 0.001) were more frequent in CA. CA was independently associated with acute kidney failure (OR 1.40 [95%CI 1.28-1.52], p < 0.001), CPR (OR 1.58 [95%CI 1.34-1.86], p < 0.001), intracerebral bleeding (OR 3.13 [95%CI 1.68-5.83], p < 0.001) and in-hospital mortality between the 5 and 8th decade of life, but in-hospital mortality was strongly influenced by cancer.

CONCLUSIONS

CA was identified as an independent risk factor for complications and in-hospital mortality in HF patients, whereby it has to be mentioned that amyloidosis subtypes could not differentiated in the present study. Physicians should be aware of this issue concerning treatments and monitoring of CA-patients.

Global epidemiology of amyloid light-chain amyloidosis

Background

Amyloid light-chain (AL) amyloidosis is an ultra-rare disease associated with significant morbidity and mortality. Few studies have examined the global epidemiology of this condition.

Methods

This study estimated the diagnosed incidence and 1-year, 5-year, 10-year, and 20-year period prevalence of AL amyloidosis in 2018 for countries in and near Europe, and in the United States (US), Canada, Brazil, Japan, South Korea, Taiwan, and Russia. A systematic literature review (SLR) was conducted to identify country-specific, age- and gender-specific diagnosed incidence of AL amyloidosis and observed survival data-point inputs for an incidence-to-prevalence model. Extrapolations were used to estimate incidence and prevalence for countries without registry or published epidemiological data.

Results

Of 171 publications identified in the SLR, 10 records met the criteria for data extraction, and two records were included in the final incidence-to-prevalence model. In 2018, an estimated 74,000 AL amyloidosis cases worldwide were diagnosed during the preceding 20 years. The estimated incidence and 20-year prevalence rates were 10 and 51 cases per million population, respectively.

Conclusions

Orphan medicinal product designation criteria of the European Medicines Agency or Electronic Code of Federal Regulations indicate that a disease must not affect > 5 in 10,000 people across the European Union or affect < 200,000 people in the US. This study provides up-to-date epidemiological patterns of AL amyloidosis, which is vital for understanding the burden of the disease, increasing awareness, and to further research and treatment options.