Immunoglobulin light chain amyloidosis: 2011 update on diagnosis, risk-stratification, and management

Phase 1a/b study of monoclonal antibody CAEL-101 (11-1F4) in patients with AL amyloidosis

Systemic immunoglobulin light-chain amyloidosis is characterized by pathologic deposition of immunoglobulin light chains as amyloid fibrils in vital organs, leading to organ impairment and eventual death. That the process is reversible was evidenced in an in vivo experimental model in which fibril-reactive chimeric monoclonal antibody (mAb) 11-1F4 directly targeted human light-chain amyloid deposits and affected their removal via a phagocyte-mediated response. To determine the tolerability and potential amyloidolytic effect of this agent (now designated mAb CAEL-101), we conducted a phase 1a/b study involving 27 patients, most of whom had manifestations of organ involvement. This was an open-label study in which phase 1a patients received mAb CAEL-101 as a single intravenous infusion with escalating dose levels from 0.5 mg/m2 to 500 mg/m2 to establish the maximum tolerated dose (MTD). In phase 1b, the antibody was administered as a graded series of 4 weekly infusions. For both phases, there were no drug-related serious adverse events or dose-limiting toxicities among recipients, and the MTD was not reached. The majority of patients had deep hematologic responses but persistent organ disease prior to treatment. Fifteen of 24 patients (63%) who manifested cardiac, renal, hepatic, gastrointestinal, or soft tissue involvement had a therapeutic response to mAb CAEL-101 as evidenced by serum biomarkers or objective imaging modalities with a median time to response of 3 weeks. Infusions of mAb CAEL-101 were well tolerated and, for the majority, resulted in improved organ function, notably for those with cardiac impairment. This trial was registered at www.clinicaltrials.gov as #NCT02245867.

Search for AL amyloidosis risk factors using Mendelian randomization

In amyloid light chain (AL) amyloidosis, amyloid fibrils derived from immunoglobulin light chain are deposited in many organs, interfering with their function. The etiology of AL amyloidosis is poorly understood. Summary data from genome-wide association studies (GWASs) of multiple phenotypes can be exploited by Mendelian randomization (MR) methodology to search for factors influencing AL amyloidosis risk. We performed a 2-sample MR analyzing 72 phenotypes, proxied by 3461 genetic variants, and summary genetic data from a GWAS of 1129 AL amyloidosis cases and 7589 controls. Associations with a Bonferroni-defined significance level were observed for genetically predicted increased monocyte counts (P = 3.8 × 10-4) and the tumor necrosis factor receptor superfamily member 17 (TNFRSF17) gene (P = 3.4 × 10-5). Two other associations with the TNFRSF (members 6 and 19L) reached a nominal significance level. The association between genetically predicted decreased fibrinogen levels may be related to roles of fibrinogen other than blood clotting. be related to its nonhemostatic role. It is plausible that a causal relationship with monocyte concentration could be explained by selection of a light chain-producing clone during progression of monoclonal gammopathy of unknown significance toward AL amyloidosis. Because TNFRSF proteins have key functions in lymphocyte biology, it is entirely plausible that they offer a potential link to AL amyloidosis pathophysiology. Our study provides insight into AL amyloidosis etiology, suggesting high circulating levels of monocytes and TNFRSF proteins as risk factors.

Predictors of cardiac involvement and survival in patients with primary systemic light-chain amyloidosis: roles of the clinical, chemical, and 3-D speckle tracking echocardiography parameters

Background

Light-chain (AL) amyloidosis is the most common type of systemic amyloidosis with poor prognosis. Currently, the predictors of cardiac involvement and prognostic staging systems are primarily based on conventional echocardiography and serological biomarkers. We used three-dimensional speckle tracking echocardiography (STE-3D) measurements of strain, hypothesizing that it could detect cardiac involvement and aid in prediction of mortality.

Methods

We retrospectively analysed 74 consecutive patients with biopsy-proven AL amyloidosis. Among them, 42 showed possible cardiac involvement and 32 without cardiac involvement. LV global longitudinal strain (GLS), global radial strain, global circumferential strain and global area strain (GAS) measurements were obtained.

Results

The GLS and GAS were considered significant predictors of cardiac involvement. The cut-off values discriminating cardiac involvement were 16.10% for GLS, 32.95% for GAS. During the median follow-up of 12.5 months (interquartile range 4–25 months), 20 (27%) patients died. For the Cox proportional model survival analysis, heart rate, cardiac troponin T, NT-proBNP levels, E/e’, GLS, and GAS were univariate predictors of death. Multivariate Cox model showed that GLS ≤ 14.78% and cardiac troponin T ≥ 0.049 mg/l levels were independent predictors of survival.

Conclusions

STE-3D measurements of LV myocardial mechanics could detect cardiac involvement in patients with AL amyloidosis; GLS and cardiac biomarkers can provided prognostic information for mortality prediction.

[Monoclonal gammapathy of renal significance (MGRS) at the current state: terminology, diagnosis and treatment]

In this article we discussed the current state of monoclonal gammapathy of renal significance (Monoclonal Gammopathy of Renal Significance MGRS) and revealed problems of B-cell clone secreting nephrotoxic monoclonal immunoglobulin identification. We followed 276 patients with monoclonal gammapathy including patients with non-amyloid nephropathy. The majority of patients had systemic AL-amyloidosis. We established better survival of the treated patients with systemic AL-amyloidosis in comparison with retrospective untreated cohort. We considered current treatment of patients with non-amyloid nephropathy and focused on the crucial role of multidisciplinary approach in management of these patients.

High Serum Lactate Dehydrogenase adds Prognostic Value to Cardiac Biomarker Staging System for Light Chain Amyloidosis

Objective: To evaluate the impact of elevated serum lactate dehydrogenase (LDH) on prognosis of immunoglobulin light chain (AL) amyloidosis, and to investigate its prognostic value for the cardiac biomarker staging system.

Patients and Methods: We analyzed 83 consecutive patients with newly diagnosed immunoglobulin light chain amyloidosis who were treated with bortezomib or thalidomide based therapies between August 2010 and May 2017.

Results: Elevated serum LDH was identified to be associated with cardiac involvement, BNP and TNT (p=0.017, p=0.007, and p=0.026, respectively). The prognosis of patients with elevated serum LDH was inferior to that of patients with normal serum LDH. The two-year PFS rates of patients with elevated serum LDH and patients with normal serum LDH were 47.8% and 68.8% respectively (p=0.009), and the corresponding two-year OS rates were 51.5% and 73.9% respectively (p=0.007). We then incorporated serum LDH into the cardiac biomarker staging system involving cTNT and NT-proBNP. Patients were assigned a score of 1 of cTNT≥0.025ng/ml, NT-proBNP≥332ng/L, and LDH≥259U/L, creating a stage I to IV with scores 0 to 3 points, respectively. The proportion of patients with stage I, II, III, and IV were 31.6%, 32.9%, 21.1%, and 14.4%. The two-year PFS rates for patients in stage I, II, III and IV were 72.6%, 53.6%, 33.7% and 20%(p<0.001), respectively. The two-year OS rates of patients were 90.9%, 66.7%, 42.9%, and 20% (p<0.001), respectively.

Conclusion: Elevated LDH had adverse influence on prognosis of AL amyloidosis, which added prognostic value to the cardiac biomarker staging system.

Prognostic value of novel imaging parameters derived from standard cardiovascular magnetic resonance in high risk patients with systemic light chain amyloidosis

BACKGROUND

The differentiated assessment of functional parameters besides morphological changes is essential for the evaluation of prognosis in systemic immunoglobulin light chain (AL) amyloidosis.

METHODS

Seventy-four subjects with AL amyloidosis and presence of late gadolinium enhancement (LGE) pattern typical for cardiac amyloidosis were analyzed. Long axis strain (LAS) and myocardial contraction fraction (MCF), as well as morphological and functional markers, were measured. The primary endpoint was death, while death and heart transplantation served as a composite secondary endpoint.

RESULTS

After a median follow-up of 41 months, 29 out of 74 patients died and 10 received a heart transplant. Left ventricular (LV) functional parameters were reduced in patients, who met the composite endpoint (LV ejection fraction 51% vs. 61%, LAS - 6.9% vs - 10%, GLS - 12% vs - 15% and MCF 42% vs. 69%; p <  0.001 for all). In unadjusted univariate analysis, LAS (HR = 1.05, p <  0.001) and MCF (HR = 0.96, p <  0.001) were associated with reduced transplant-free survival. Kaplan-Meier analyses showed a significantly lower event-free survival in patients with reduced MCF. MCF and LAS performed best to identify high risk patients for secondary endpoint (Log-rank test p <  0.001) in a combined model. Using sequential Cox regression analysis, the addition of LAS and MCF to LV ejection fraction led to a significant increase in the predictive power of the model (χ2 (df = 1) = 28.2, p <  0.001).

CONCLUSIONS

LAS and MCF as routinely available and robust CMR-derived parameters predict outcome in LGE positive AL amyloidosis. Patients with impaired LV function in combination with reduced LAS and MCF are at the highest risk for death and heart transplantation.

Suspected Pericardial Tuberculosis Revealed as an Amyloid Pericardial Mass

Primary systemic amyloidosis is not easily diagnosed. The immunoglobulin deposits are usually localized in the kidney, heart, and liver. We describe an unusual case of a patient suffering from a pericardial amyloidoma with internal calcifications and air bubbles that compressed the right ventricle and shifted the heart to the left. Since the patient was in shock, urgent pericardiotomy was performed. This site showed PET uptake. A monoclonal component was present. On these findings, differential diagnoses included multiple myeloma and atypical pericardial tuberculosis, whereas a periumbilical fat tissue biopsy demonstrated amyloidosis. A previous Salmonella species infection had most likely stimulated the production of amyloid. The patient received bortezomib/dexamethasone treatment and achieved a good response.

Systemic Amyloidosis and Extraocular Muscle Deposition

Isolated amyloid deposition in an extraocular muscle is a rare event but can be a presenting feature of systemic amyloidosis. A 67-year-old woman with an acquired exotropia and hypertropia was found to have unilateral diffuse extraocular muscle enlargement on magnetic resonance imaging. Owing to the progressive nature of her strabismus and the negative laboratory testing for thyroid disease, she underwent an extraocular muscle biopsy that revealed amyloid deposition. Further workup demonstrated a monoclonal gammopathy consistent with systemic amyloidosis. This case demonstrates the need to consider amyloidosis in the differential diagnosis of patients presenting with an atypical acquired strabismus. We review other reports of isolated amyloid deposition in extraocular muscles and its association with systemic amyloidosis, emphasizing the importance of the ophthalmologist in the early recognition of this disease to prevent irreversible, life-threatening end organ damage.

Myocardial Deformation in Cardiac Amyloid Light-chain Amyloidosis: Assessed with 3T Cardiovascular Magnetic Resonance Feature Tracking

Clinically, assessment of myocardial function is essential in patients with amyloid light-chain cardiac amyloidosis (AL-CA) to predict outcome and determine therapeutic approach. The aim of this study was to investigate the feasibility of cardiovascular magnetic resonance (CMR)-derived feature tracking algorithm for assessing left ventricular (LV) myocardial deformation in AL-CA, and to determine if these abnormal myocardial deformation parameters are correlated to impaired LV myocardial microvascular dysfunction. A total of 42 AL-CA patients, including 26 with preserved systolic function and 16 with impaired LVEF, and 35 healthy controls were enrolled and underwent CMR examination. Our result indicated that AL-CA patients had significantly reduced global peak strain (PS) (longitudinal, circumferential, and radial) (all P < 0.05). AL-CA patients with normal LVEF showed preserved longitudinal PS at apical and significantly reduced longitudinal PS at mid and basal segments. By Spearman’s rank correlation analysis, the LV regional radial, circumferential, and longitudinal myocardial deformation values were correlated to myocardial upslope and MaxSI in CA, regardless of LVEF. This study indicated that the abnormal LV myocardial deformation of AL-CA patients can be monitored using feature tracking CMR, even in those with preserved LVEF; and the myocardial deformation was associated with coronary microvascular dysfunction.

Renal lesions associated with monoclonal gammopathies of undetermined significance: clinical forms, mechanisms of development, approaches to treatment

The term «monoclonal gammopathies of undetermined significance» (MGUS) was introduced by R. Kyle in 1978 to designate the condition characterized by the presence ofsmall amounts ofM-protein in the serum. In some patients, such condition remains benign for a long time but predetermines for the development of multiple myeloma and other B-lymphocytic tumours. Also, it can provoke non-cancerous diseases due to the toxic action of monoclonal proteins (immunoglobulins and free light chains) on various organs, especially kidneys. MGUS-associated renal lesions include glomerulopathies with organized deposits, such as AL-amyloidosis (amyloid light chain of immunoglobulin), cryoglobulinic and immunotactoid glomerulonephritis, and with unorganized deposits (light chain deposition and proliferative forms of idiopathic glomerulonephritis. The available experimental data throw light on the possible mechanisms of renal lesions. We summarized the literature data and original observations to describe methods for differential diagnostics of MGUS-associated renal lesions including the highly sensitive test for free light chine identification (Freelite method) and principles of pathogenetic treatment by the impact on the pathological B-cell clone.

[Oligosecretory monoclonal gammopathy with renal involvement]

The article deals with the so-called monoclonal gammopathy of undetermined significance (MGUS), which is being actively explored in the world and has been recently investigated in Russia. It indicates the principles of identifying the phenotypes of MGUS and criteria for assessing the risk of its progression to cancer. There is an update on the possible involvement of monoclonal proteins in the pathogenesis of certain non-neoplastic kidney diseases, renal injuries in particular. The paper gives their classification and enumerates differential diagnostic techniques, including the Freelite method, a highly sensitive one to determine free light chains (FLC), prognostic criteria, and approaches to treating each separate form in relation to the phenotype of a monoclonal protein. The authors present their own data on detection rates for MGUS at a multidisciplinary hospital and a clinical case of MGUS-associated membranoproliferative glomerulonephritis, by justifying a treatment regimen containing bortezomib (velcade).

Regional myocardial microvascular dysfunction in cardiac amyloid light-chain amyloidosis: assessment with 3T cardiovascular magnetic resonance

BACKGROUND

Coronary microvascular dysfunction is highly prevalent in patients with amyloid light-chain (AL) cardiac amyloidosis (AL-CA). The aim of this study was to clarify the feasibility of first-pass perfusion imaging using 3 T cardiovascular magnetic resonance (CMR) for evaluating the difference in left ventricular (LV) regional myocardial microvascular function among normal subjects and in patients with AL-CA. The amyloidosis patients were classified into those with impaired systolic function [LV ejection fraction (LVEF) < 50 %] and those with preserved systolic function.

METHODS

In total, 32 patients with biopsy-proven AL-CA, including 11 AL-CA patients with systolic dysfunction, 21 AL-CA patients with preserved systolic function, and 25 healthy subjects, underwent CMR examination. LV regional myocardial perfusion parameters included upslope, time to maximum signal intensity (TTM) and max signal intensity (MaxSI) were compared among the three patient groups. Receiver operating characteristic analysis was performed to determine whether perfusion parameters could be used in discriminating regional myocardial microvascularity between AL-CA patients and normal subjects.

RESULTS

The patients with AL-CA had significantly reduced first-pass perfusion upslope and MaxSI, and increased TTM compared with the normal subjects (all P < 0.01). Compared with the patients with AL-CA and preserved LVEF, the patients with AL-CA and impaired systolic function had a longer TTM in the basal (47.05 ± 16.59 vs. 39.68 ± 19.11; P = 0.002) and mid-ventricular (44.61 ± 16.34 vs. 37.74 ± 18.25; P = 0.002) segments; lower upslope in the basal (2.41 ± 1.32 vs. 3.60 ± 1.68; P < 0.0001), mid-ventricular (2.82 ± 1.34 vs. 4.15 ± 2.02; P < 0.0001), and apical (3.71 ± 1.38 vs. 4.97 ± 2.55; P = 0.004) segments; and lower MaxSI (31.67 ± 15.23 vs. 37.96 ± 11.15; P < 0.0001) in the basal segment. The ROC curve analysis revealed that the first-pass upslope, TTM, and MaxSI may be used as indicators for differentiating microcirculation between AL-CA patients with preserved or impaired systolic function and normal subjects.

CONCLUSIONS

The differences in LV regional myocardial microvascular function among normal subjects, AL-CA patients with systolic dysfunction, and AL-CA patients with preserved systolic function can be monitored using first-pass perfusion CMR.

The impact of dialysis on the survival of patients with immunoglobulin light chain (AL) amyloidosis undergoing autologous stem cell transplantation

BACKGROUND

Acute renal failure requiring dialysis is associated with high mortality during autologous stem cell transplantation (ASCT). This study examined the association between acute renal failure and mortality in immunoglobulin light chain (AL) amyloidosis during ASCT.

METHODS

Between 1996 and 2010, 408 ASCT patients were evaluated. Data were collected from electronic medical records.

RESULTS

Dialysis was performed on 72 (17.6%) patients. Eight patients started dialysis >30 days prior to ASCT (Group II), 36 started ±30 days after ASCT (Group III) and 28 initiated dialysis >1 month after ASCT (Group IV). Patients who never dialyzed were assigned to Group I. There were no significant age or sex differences. Median overall survival (OS) had not been reached in Groups I and II but was 7.0 months in Group III and 48.5 months in Group IV (P < 0.001). Treatment-related mortality (TRM) was observed in 44.4% of the patients in Group III, 6-fold higher than the next highest group (P < 0.001). The most common causes of TRM were cardiac and sepsis. In the multivariate analysis, only hypoalbuminemia (<2.5 g/dL, P < 0.001) and estimated glomerular filtration rate (eGFR) <40 mL/min/1.73 m(2) (P < 0.001) were independently associated with starting dialysis within 30 days of ASCT.

CONCLUSIONS

The study found significant differences in the OS depending on when the acute renal failure occurred. Patients who required dialysis within 30 days of ASCT had the highest rate of TRM. Screening with serum albumin and eGFR may reduce the risk.

Targeting protein aggregation for the treatment of degenerative diseases

The aggregation of specific proteins is hypothesized to underlie several degenerative diseases, which are collectively known as amyloid disorders. However, the mechanistic connection between the process of protein aggregation and tissue degeneration is not yet fully understood. Here, we review current and emerging strategies to ameliorate aggregation-associated degenerative disorders, with a focus on disease-modifying strategies that prevent the formation of and/or eliminate protein aggregates. Persuasive pharmacological and genetic evidence now supports protein aggregation as the cause of postmitotic tissue dysfunction or loss. However, a more detailed understanding of the factors that trigger and sustain aggregate formation and of the structure-activity relationships underlying proteotoxicity is needed to develop future disease-modifying therapies.

Treatment of hepatic amyloid light-chain amyloidosis with bortezomib and dexamethasone in a liver transplant patient

Hepatic amyloid light-chain (AL) amyloidosis is characterized by abnormal deposition of amyloid fibrils in the liver. As this precursor protein is produced by a proliferative plasma cell clone in the bone marrow, liver transplantation (LT) does not affect the disease's progression. Here, we describe the successful treatment using bortezomib- and dexamethasone-based chemotherapy, following LT, of hepatic AL amyloidosis in a 65-year-old woman with progressive liver failure. The patient presented with progressive hepatic dysfunction accompanied by hepatorenal syndrome requiring hemodialysis, and living donor LT was successfully performed. Histology revealed amyloid deposits in the liver and stomach, and serum immunofixation revealed AL amyloidosis (κ-type). The patient began chemotherapy on day 45 after the LT, and remission was achieved after one course. She was subsequently discharged 83 days after the LT, with normal liver and renal function, and no clinical evidence of recurrent disease was observed at the latest follow up (22 months post-LT).

Kinetics of organ response and survival following normalization of the serum free light chain ratio in AL amyloidosis

Despite successful treatment of the clonal plasma cell implicated in its pathogenesis, patients with AL amyloidosis (AL) experience significant morbidity related to underlying amyloid mediated organ dysfunction. While normalization of the serum free light chain measurements [normal ratio of involved and uninvolved free light chains (nFLCr)] is the goal of therapy and centerpiece of hematologic response criteria, achieving (or not achieving) meaningful organ response (OR) is clinically significant for its implications on long-term symptomatology as well as overall survival (OS), and remains the ultimate goal of treatment. Expectations for organ recovery following successful therapy leading to nFLCr in AL remain poorly described. We evaluated the timeframe and predictive factors for OR, and long-term outcome, in 313 AL patients who achieved nFLCr following therapy initiation. OR was seen in 80% of surviving AL patients within 1-year of nFLCr. Patients achieving early OR within 1 year of nFLCr had superior OS compared with those who despite obtaining nFLCr did not achieve early OR. We further evaluated factors predicting OR and OS among patients achieving nFLCr. Higher values of dFLC (involved-uninvolved) at diagnosis predict OR, and early OR predicts improved OS following successful hematologic therapy in AL.

Prognostic significance of semiautomatic quantification of left ventricular long axis shortening in systemic light-chain amyloidosis

AIMS

To assess left ventricular long axis shortening (LAS) in patients with AL amyloidosis as a potential predictor for outcome.

METHODS AND RESULTS

We performed a de novo echocardiographic analysis of LAS in 120 patients with biopsy-proven AL amyloidosis evaluated at first presentation before specific treatment. Additionally, 47 control subjects were analyzed retrospectivly. LAS was measured using a semiautomatic tissue motion annular displacement software algorithm (TMAD). LAS was significantly better than ejection fraction (EF) (p < 0.0001) and M-mode-derived mitral annular plane systolic excursion (MAPSE) (p < 0.05) discriminating AL patients from control subjects, while being non-inferior compared to tissue Doppler-derived peak systolic mitral annular velocity. One year outcome analysis in patients with AL amyloidosis showed that LAS remained the only significant echocardiographic parameter (HR:0.76; p < 0.005) in a multivariable Cox regression model of echocardiographic values. In a comprehensive clinical model, LAS (HR:0.72, p < 0.0001), cardiac troponin-T (HR:2.86, p < 0.01) and free light chain difference (HR:1.00; p < 0.05) were independently associated with the outcome. Assessment of LAS led to a significant integrated discrimination improvement and offered incremental information compared to EF and biomarkers. The cut-off value for LAS discriminating the endpoint was 5.8%.

CONCLUSION

LAS was an independent predictor of survival within the first year and offers incremental information in patients with AL amyloidosis evaluated prior to specific treatment.

Characteristics and long-term outcome of patients with systemic immunoglobulin light-chain amyloidosis

BACKGROUND/AIMS

Immunoglobulin light-chain (AL) amyloidosis is a systemic disorder that causes progressive organ dysfunction. The optimal treatment strategy requires accurate patient stratification with an emphasis on the extent of cardiac involvement. Reports on its prognosis are sparse and predominantly originate from highly selected centers. We aimed to evaluate patient characteristics and outcomes in a cohort treated at a single center.

METHODS

This is a single-center retrospective study of 63 consecutive patients diagnosed with AL amyloidosis between January 2000 and December 2012. Patients were evaluated by treatment strategy and cardiac involvement.

RESULTS

The mean age at diagnosis was 61.4 years (±8.9), and 39 patients (62%) were male. Thirty-two (51%) patients presented with cardiac amyloid involvement (CA) and the remaining 31 (49%) had noncardiac amyloidosis (NCA). The median follow-up time was 12.7 months (0.3-90.8), and 38 (60%) patients died during follow-up. The median overall survival (OS) was 29 months (95% CI 12.1-57.2) and the OS was not significantly lower for patients with CA compared to NCA (log-rank = 0.21).

CONCLUSION

The prognosis in AL amyloidosis is grave, but the outcome with treatment in the current series was comparable to those in series from larger centers. CA did not significantly predict the OS.

Pathophysiology and treatment of cardiac amyloidosis

Amyloid cardiomyopathy should be suspected in any patient who presents with heart failure and preserved ejection fraction. In patients with echocardiographic evidence of ventricular thickening and without a clear history of hypertension, infiltrative cardiomyopathy should be considered. If imaging suggests the presence of amyloid deposits, confirmation by biopsy is required, although endomyocardial biopsy is generally not necessary. Assessment of aspirated subcutaneous fat and bone-marrow biopsy samples verifies the diagnosis in 40-80% of patients, dependent on the type of amyloidosis. Mass spectroscopy can be used to determine the protein subunit and classify the disease as immunoglobulin light-chain amyloidosis or transthyretin-related amyloidosis associated with mutant or wild-type TTR (formerly known as familial amyloid cardiomyopathy and senile cardiac amyloidosis, respectively). In this Review, we discuss the characteristics of cardiac amyloidosis, and present a structured approach to both the assessment of patients and treatment with emerging therapies and organ transplantation.

Amyloid goiter related with Crohn's disease: A rare association: Amyloid goiter secondary to Crohn's disease

INTRODUCTION

Amyloid goiter (AG) is characterized by enlargement of the thyroid gland as a result of extensive amyloid deposition in a bilateral and diffuse manner.

PRESENTATION OF CASE

A 58-year-old male patient was diagnosed of Crohn's Disease (CD). He was admitted to our clinic with complaint of respiratory distress and rapid growth swelling in the neck. Ultrasound examination revealed huge multinodular goiter on both sides of thyroid gland. We performed bilateral total thyroidectomy. Pathological evaluation revealed AG.

DISCUSSION

Amyloid leads to degeneration in tissues, thereby disrupts the function of the relevant organs. It is important to distinguish AG from other reasons of goiter, particularly thyroid medullary cancer that can cause amyloid deposition in thyroid gland. Secondary amyloidosis frequently involves thyroid gland at microscopic level, but rarely causes goiter. An analysis of current literature revealed that only few cases of AG occurred secondary to CD. Herein we presented a case of AG who has rapidly growing goiter that associated with CD.

CONCLUSION

AG must be kept in mind in case of rapidly growing goiter, especially in patients with chronic inflammatory bowel diseases.

Efficacy of bortezomib, cyclophosphamide and dexamethasone in treatment-naïve patients with high-risk cardiac AL amyloidosis (Mayo Clinic stage III)

Bortezomib is an active agent in AL amyloidosis and responses to this drug in combination with cyclophosphamide and dexamethasone are both rapid and deep. Here we present an international, multicenter series of 60 patients with Mayo Clinic stage III cardiac amyloidosis to assess the impact of this regimen in improving outcomes in this poor-risk group. The median follow-up for the entire cohort is 11.8 months. The overall response rate was 68%. In a landmark analysis, examining patients who survived more than 3 months, the overall response rate was 86%. A cardiac response was seen in 32% of patients. The estimated 1-year survival rate for the whole cohort was 57% and 24 patients (40%) died while on therapy. Although unable to save the poorest risk patients, the combination of bortezomib, cyclophosphamide and dexamethasone can achieve a high number of hematologic and cardiac responses, likely improving overall survival and justifying a prospective trial.

[Cardiac amyloidosis: a case series of 14 patients, description and prognosis]

PURPOSE

Cardiac amyloidosis is rare. The objective of this study was to report on a case series of 14 patients with cardiac amyloidosis and to study the prognostic factors.

METHODS

Monocentric retrospective study of all adult patients who presented with cardiac amyloidosis, diagnosed at the Georges-Pompidou European hospital in Paris between 2003 and 2011.

RESULTS

Fourteen patients were identified (10 men and four women). Median age at diagnosis was 66.5 years. Twelve patients were diagnosed with AL amyloidosis, one with AA amyloidosis, and one with transthyretin amyloidosis. All patients presented cardiac manifestations: heart failure (n=9), rhythm disorders (n=6). Eight patients presented extra-cardiac manifestations of amyloidosis: renal (n=8), gastrointestinal (n=5). Troponin serum level was increased in eight patients and BNP level was superior to 400 pg/L in 12 patients. When performed, the cardiac magnetic resonance imaging (MRI) showed, in six patients out of seven, chamber dilatation, concentric hypertrophy or late enhancement. Among patients with cardiac failure at diagnosis (n=9), seven died with a median survival of 1 month duration. Factors of poor prognosis were, in our study, heart failure, elevated levels of troponin and BNP, and the AL amyloidosis subtype.

CONCLUSION

Cardiac amyloidosis, especially the AL type, has a very poor prognosis, essentially because of an underlying multiple myeloma and heart failure.

An historic perspective of proteasome inhibition

The ubiquitin-proteasome system (UPS) and associated signaling pathways are regarded today as an exciting area of development for novel therapeutics. However, two decades ago, following the discovery and elucidation of ubiquitin and the 26S proteasome as key mediators of protein turnover, the concept of inhibiting the UPS was not even considered a feasible therapeutic approach due to the assumption that inhibition of this pathway would have widespread deleterious effects. Subsequent clinical developments with the first-in-class proteasome inhibitor bortezomib have radically overturned that view, with the proteasome now recognized as a validated target and proteasome inhibition demonstrated to be a highly successful treatment for a number of hematologic malignancies. Here we provide a historic perspective on the emergence of proteasome inhibition, sharing some of the lessons learned along the way. We describe the development of bortezomib and the elucidation of the effects of its novel mechanism of action, and place the cutting-edge work described elsewhere in this issue in the context of these historic developments.

Heart transplantation and end-stage cardiac amyloidosis: a review and approach to evaluation and management

Cardiac amyloidosis is one of the most common of the infiltrative cardiomyopathies and is associated with a poor prognosis. The extent of cardiac involvement with amyloid deposition is an important determinant of treatment options and is the major determinant of outcome in patients with amyloidosis. Several small case series with sequential orthotopic heart transplantation and autologous stem cell transplant have demonstrated an improvement in post-transplant outcome and have revived enthusiasm about heart transplantation for patients with end-stage heart failure due to AL amyloidosis. The purpose of this review is to summarize the evaluation and management of cardiac amyloidosis and to provide our single-center experience with end-stage heart failure due to AL amyloidosis treated with heart transplantation followed by an autologous stem cell transplant.

Human amyloidogenic light chain proteins result in cardiac dysfunction, cell death, and early mortality in zebrafish

Systemic amyloid light-chain (AL) amyloidosis is associated with rapidly progressive and fatal cardiomyopathy resulting from the direct cardiotoxic effects of circulating AL light chain (AL-LC) proteins and the indirect effects of AL fibril tissue infiltration. Cardiac amyloidosis is resistant to standard heart failure therapies, and, to date, there are limited treatment options for these patients. The mechanisms underlying the development of cardiac amyloidosis and AL-LC cardiotoxicity are largely unknown, and their study has been limited by the lack of a suitable in vivo model system. Here, we establish an in vivo zebrafish model of human AL-LC-induced cardiotoxicity. AL-LC isolated from AL cardiomyopathy patients or control nonamyloidogenic LC protein isolated from multiple myeloma patients (Con-LC) was directly injected into the circulation of zebrafish at 48 h postfertilization. AL-LC injection resulted in impaired cardiac function, pericardial edema, and increased cell death relative to Con-LC, culminating in compromised survival with 100% mortality within 2 wk, independent of AL fibril deposition. Prior work has implicated noncanonical p38 MAPK activation in the pathogenesis of AL-LC-induced cardiotoxicity, and p38 MAPK inhibition via SB-203580 rescued AL-LC-induced cardiac dysfunction and cell death and attenuated mortality in zebrafish. This in vivo zebrafish model of AL-LC cardiotoxicity demonstrates that antagonism of p38 MAPK within the AL-LC cardiotoxic signaling response may serve to improve cardiac function and mortality in AL cardiomyopathy. Furthermore, this in vivo model system will allow for further study of the molecular underpinnings of AL cardiotoxicity and identification of novel therapeutic strategies.

Chronic myopathy due to immunoglobulin light chain amyloidosis

Amyloid myopathy associated with a plasma cell dyscrasia is a rare cause of muscle hypertrophy. It can be a challenging diagnosis, since pathological findings are often elusive. In addition, the mechanism by which immunoglobulin light-chain deposition stimulates muscle overgrowth remains poorly understood. We present a 53-year old female with a 10-year history of progressive generalized muscle overgrowth. Congo-red staining and immunohistochemistry revealed perivascular lambda light chain amyloid deposits, apparent only in a second muscle biopsy. The numbers of central nuclei and satellite cells were increased, suggesting enhanced muscle progenitor cell formation. Despite the chronicity of the light chain disease, the patient showed complete resolution of hematologic findings and significant improvement of her muscle symptoms following autologous bone marrow transplantation. This case highlights the importance of early diagnosis and therapy for this treatable cause of a chronic myopathy with muscle hypertrophy.

Symptomatic primary (Al) amyloidosis of the stomach and duodenum

Primary (AL) amyloidosis of the gastrointestinal tract is relatively rare, and symptomatic amyloidosis of the stomach is even more seldom. We present the case of a patient who was referred to upper endoscopy because of weight loss, nausea, and vomiting. Large areas of intramucosal hemorrhages were seen, and biopsies resulted in profuse bleeding stopped with endoscopic clips. The biopsies showed amyloid depositions and further workup revealed that the patient also had cardiac and neuropathic involvements. The patient started treatment with dexamethasone, melphalan and bortezomib. After treatment was started the nausea and epigastric discomfort improved, and a reduction in the biochemical markers troponin T, NT-proBNP, and M-component was observed. Gastric amyloidosis is rarely seen at upper endoscopy in patients without a previously established diagnosis, but the unusual endoscopic findings and bleeding tendency after biopsy should be kept in mind by gastroenterologists.

Differential diagnosis of monoclonal gammopathy of undetermined significance

Monoclonal gammopathy of undetermined significance (MGUS) is an asymptomatic plasma cell disorder occurring in 4.2% of adults > 50 years of age, which can progress into symptomatic diseases either through proliferation of the plasma cell clone, giving rise to multiple myeloma and other lymphoplasmacellular neoplasms, or through organ damage caused by the monoclonal protein, as seen in light-chain amyloidosis and related conditions. Differential diagnosis of asymptomatic and symptomatic monoclonal gammopathies is the determinant for starting therapy. The criteria for determining end-organ damage should include markers of organ injury caused by the monoclonal protein. Patient assessment and optimal follow-up are now performed using risk stratification models that should also take into account the risk of developing AL amyloidosis. Patients with low-risk MGUS (approximately 40% of all MGUS patients) need limited assessment and very infrequent follow-up. The ongoing development of novel molecular biomarkers and advanced imaging techniques will improve the identification of high-risk patients who may benefit from early therapeutic intervention through innovative clinical trials.

Incidence and survival in non-hereditary amyloidosis in Sweden

Background

Amyloidosis is a heterogeneous disease caused by deposition of amyloid fibrils in organs and thereby interfering with physiological functions. Hardly any incidence data are available and most survival data are limited to specialist clinics.

Methods

Amyloidosis patients were identified from the Swedish Hospital Discharge and Outpatients Registers from years 2001 through 2008.

Results

The incidence of non-hereditary amyloidosis in 949 patients was 8.29 per million person-years and the diagnostic age with the highest incidence was over 65 years. Secondary systemic amyloidosis showed an incidence of 1 per million and a female excess and the largest number of subsequent rheumatoid arthritis deaths; the median survival was 4 years. However, as rheumatoid arthritis deaths also occurred in other diagnostic subtypes, the incidence of secondary systemic amyloidosis was likely to be about 2.0 per million. The median survival of patients with organ-limited amyloidosis was 6 years. Most myeloma deaths occurred in patients diagnosed with unspecified or ‘other’ amyloidosis. These subtypes probably accounted for most of immunoglobulin light chain (AL) amyloidosis cases; the median survival time was 3 years.

Conclusions

The present diagnostic categorization cannot single out AL amyloidosis in the Swedish discharge data but, by extrapolation from myeloma cases, an incidence of 3.2 per million could be ascribed to AL amyloidosis. Similarly, based on rheumatoid arthritis death rates, an incidence of 2.0 could be ascribed to secondary systemic amyloidosis.

Anxiety and depression among AL amyloidosis patients: the role of cardiac symptoms

Light-chain (AL) amyloidosis has the worst prognosis out of the different forms of cardiac amyloidosis, However, data are not available about the incidence of the disease-related psychological impact of AL amyloidosis in this population. In particular, no data are available about the impact of diagnosis communication or about the impact of cardiac symptom onset and severity on anxiety and depression levels among AL patients.

AIM

To evaluate the role of time that has passed since the diagnosis was communicated, time that has passed since the onset of cardiac symptoms, and actual cardiac symptom severity have on level of anxiety, depression and psychological stress among cardiology patients with AL. Thirty-two AL patients with cardiac-related symptoms were administered General Health Questionnaire, State-Trait Anxiety Inventory and Centre for Epidemiological Study-Depression Scale. Clinical variables such as months gone by since diagnosis, months gone by since the onset of cardiac symptoms, and cardiac symptom severity (New York Heart Association (NYHA) class) were measured. Troponin, NT-pro BNP levels, Mayo Stage and echocardiographic characteristics were also collected.

RESULTS

According to questionnaire normative values, AL patients presented severe psychological distress, severe anxiety and clinical depression. Moreover, anxiety levels were determined by psychological distress (p < 0.001) and months gone by since the onset of cardiac symptoms (p < 0.01) while depression levels were influenced by NYHA class (p < 0.001).

CONCLUSIONS

Our results suggest that there is a need to plan psychological support for these patients with consideration for the onset of cardiac symptoms and symptom severity.

Amyloid fibrils trigger the release of neutrophil extracellular traps (NETs), causing fibril fragmentation by NET-associated elastase

The accumulation of amyloid fibrils is a feature of amyloid diseases, where cell toxicity is due to soluble oligomeric species that precede fibril formation or are formed by fibril fragmentation, but the mechanism(s) of fragmentation is still unclear. Neutrophil-derived elastase and histones were found in amyloid deposits from patients with different systemic amyloidoses. Neutrophil extracellular traps (NETs) are key players in a death mechanism in which neutrophils release DNA traps decorated with proteins such as elastase and histones to entangle pathogens. Here, we asked whether NETs are triggered by amyloid fibrils, reasoning that because proteases are present in NETs, protease digestion of amyloid may generate soluble, cytotoxic species. We show that amyloid fibrils from three different sources (α-synuclein, Sup35, and transthyretin) induced NADPH oxidase-dependent NETs in vitro from human neutrophils. Surprisingly, NET-associated elastase digested amyloid fibrils into short species that were cytotoxic for BHK-21 and HepG2 cells. In tissue sections from patients with primary amyloidosis, we also observed the co-localization of NETs with amyloid deposits as well as with oligomers, which are probably derived from elastase-induced fibril degradation (amyloidolysis). These data reveal that release of NETs, so far described to be elicited by pathogens, can also be triggered by amyloid fibrils. Moreover, the involvement of NETs in amyloidoses might be crucial for the production of toxic species derived from fibril fragmentation.

The transthyretin amyloidoses: from delineating the molecular mechanism of aggregation linked to pathology to a regulatory-agency-approved drug

Transthyretin (TTR) is one of the many proteins that are known to misfold and aggregate (i.e., undergo amyloidogenesis) in vivo. The process of TTR amyloidogenesis causes nervous system and/or heart pathology. While several of these maladies are associated with mutations that destabilize the native TTR quaternary and/or tertiary structure, wild-type TTR amyloidogenesis also leads to the degeneration of postmitotic tissue. Over the past 20 years, much has been learned about the factors that influence the propensity of TTR to aggregate. This biophysical information led to the development of a therapeutic strategy, termed "kinetic stabilization," to prevent TTR amyloidogenesis. This strategy afforded the drug tafamidis which was recently approved by the European Medicines Agency for the treatment of TTR familial amyloid polyneuropathy, the most common familial TTR amyloid disease. Tafamidis is the first and currently the only medication approved to treat TTR familial amyloid polyneuropathy. Here we review the biophysical basis for the kinetic stabilization strategy and the structure-based drug design effort that led to this first-in-class pharmacologic agent.

Longitudinal left ventricular function for prediction of survival in systemic light-chain amyloidosis: incremental value compared with clinical and biochemical markers

OBJECTIVES

The aim of the study was to determine whether longitudinal left ventricular (LV) function provides prognostic information in a large cohort of patients with systemic light-chain (AL) amyloidosis.

BACKGROUND

AL amyloidosis is associated with a high incidence of cardiovascular events. Reduced myocardial longitudinal function is one of the hallmarks of myocardial involvement in this rare disease.

METHODS

Two hundred six consecutive patients with biopsy-proven AL amyloidosis were investigated in this prospective observational study. Echocardiographic imaging parameters, mean tissue Doppler-derived longitudinal strain (LS), and two-dimensional global longitudinal strain (2D-GLS) of the LV, cardiac serological biomarkers, and comprehensive clinical disease characteristics were assessed. The primary endpoint was all-cause mortality or heart transplantation.

RESULTS

After a median follow-up of 1207 days, LS and 2D-GLS were significant predictors of survival in AL amyloidosis. The cutoff values discriminating survivors from nonsurvivors were -10.65% for LS and -11.78% for 2D-GLS. In a multivariable echocardiographic Cox model, only diastolic dysfunction and 2D-GLS remained as independent predictors of survival. In comprehensive clinical models, 2D-GLS (p < 0.0001), diastolic dysfunction (p < 0.01), the pathologic free light chains (p < 0.05), cardiac troponin-T (cTnT) (p < 0.01), and the Karnofsky index (p < 0.001) remained as independent predictors. 2D-GLS delineated a superior prognostic value compared with that derived from pathologic free light chains or cTnT in patients evaluated before firstline chemotherapy (n = 113; p < 0.0001), and remained the only independent predictor besides the Karnofsky index in subjects with preserved LV ejection fraction (≥50%; n = 127; p < 0.01). LS and 2D-GLS both offered significant incremental information (p < 0.001) for the assessment of outcome compared with clinical variables (age, Karnofsky index, and New York Heart Association functional class) and serological biomarkers.

CONCLUSIONS

In the largest serial investigation reported so far, reduced LV longitudinal function served as an independent predictor of survival in AL amyloidosis and offered incremental information beyond standard clinical and serological parameters.

Lenalidomide, cyclophosphamide, and dexamethasone (CRd) for light-chain amyloidosis: long-term results from a phase 2 trial

Light-chain (AL) amyloidosis remains incurable despite recent therapeutic advances. Given the activity of the lenalidomide-alkylating agent combination in myeloma, we designed this phase 2 trial of lenalidomide, cyclophosphamide, and dexamethasone in AL amyloidosis. Thirty-five patients, including 24 previously untreated, were enrolled. Nearly one-half of the patients had cardiac stage III disease and 28% had ≥ 3 organs involved. The overall hematologic response (≥ partial response [PR]) rate was 60%, including 40% with very-good partial response or better. Using serum-free light chain for assessing response, 77% of patients had a hematologic response. Organ responses were seen in 29% of patients and were limited to those with a hematologic response. The median hematologic progression-free survival was 28.3 months, and the median overall survival was 37.8 months. Hematologic toxicity was the predominant adverse event, followed by fatigue, edema, and gastrointestinal symptoms. A grade 3 or higher toxicity occurred in 26 patients (74%) including ≥ grade 3 hematologic toxicity in 16 patients (46%) and ≥ grade 3 nonhematologic toxicity in 25 patients (71%). Seven patients (20%) died on study, primarily because of advanced disease. Lenalidomide, cyclophosphamide, and dexamethasone (CRd) is an effective combination for treatment of AL amyloidosis and leads to durable hematologic responses as well as organ responses with manageable toxicity. The trial was registered at www.clinicaltrials.gov (NCT00564889).

An update on monoclonal gammopathy and neuropathy

Peripheral neuropathy associated with monoclonal gammopathy is a rare but important cause of neuropathy that can herald serious underlying disease. IgM monoclonal gammopathy of undetermined significance (MGUS) is the most commonly found monoclonal gammopathy associated with neuropathy, with characteristic clinical, electrophysiologic, and pathologic features. The IgG and IgA monoclonal gammopathies are rarely associated with specific neuropathies. Standard immunomodulatory agents including steroids, intravenous immunoglobulin, and plasmapheresis have shown limited efficacy in IgM MGUS. Neuropathies associated with specific lymphoproliferative disorders may not respond to treatments aimed at that disorder. Case series had shown promising results with rituximab, a monoclonal antibody that targets the B cell surface antigen CD20 and results in a rapid and sustained depletion of B cells; however, two recent randomized controlled trials with rituximab failed to provide evidence of efficacy in primary outcome measures, despite reduction in antibody levels. Long-term studies looking at the association between specific immunologic markers and disease recurrence are needed to ultimately develop targeted therapies.