Prospective urinary albumin/creatinine ratio for diagnosis, staging, and organ response assessment in renal AL amyloidosis: results from a large cohort of patients

Objectives Quantification of 24 h-proteinuria is the gold standard for diagnosing, staging, and monitoring of patients with renal AL amyloidosis. However, 24 h-urine collection is cumbersome and may result in preanalytical error. In this prospective study, we investigated the role of urinary albumin/creatinine ratio (UACR) (cut-off: 300 mg/g) identifying renal involvement, evaluated a UACR-based staging system (UACR cut-off: 3,600 mg/g) and assessed whether UACR response (UACR decrease >30% without worsening in eGFR >25%) predicts renal outcome in 531 patients with newly-diagnosed AL amyloidosis. Methods From October 2013 paired 24 h-proteinuria and UACR (on first morning void) were measured in all newly-diagnosed patients with AL amyloidosis. Correlation between 24 h-proteinuria and UACR at baseline was assessed by Pearson’s r test. Impact of UACR response on renal outcome was assessed in randomly created testing (n=354) and validation (n=177) cohorts. Results A strong linear correlation was found between 24 h-proteinuria and UACR at baseline (r=0.90; p<0.001). After a median follow-up of 31 months, 57 (11%) patients required dialysis. A UACR-based renal staging system identified three stages with significantly higher dialysis rate at 36 months comparing stage I with stage II and stage II with stage III. Achieving a renal response, according to a UACR-based criterion, resulted in lower dialysis rate in both testing and validation cohorts. Conclusions UACR is a reliable marker for diagnosis, prognosis, and organ response assessment in renal AL amyloidosis and can reliably replace 24 h-proteinuria in clinical trials and individual patients’ management.

Mechanisms of Organ Damage and Novel Treatment Targets in AL Amyloidosis

The deposition of amyloid light chains (LCs) in target sites translates into tissue damage and organ dysfunction. Clinical and experimental advances have cast new light on the pathophysiology of damage in AL amyloidosis. The currently accepted view is that, besides the alterations caused by fibrillar deposits in the extracellular space, direct proteotoxicity exerted by prefibrillar LC species is an important pathogenic factor. As our knowledge on the pathological species and altered cellular pathways grows, novel potential therapeutic strategies to prevent or reduce damage can be rationally explored. Complementing chemotherapy with approaches aimed at disrupting the deposited fibrils and stabilizing prefibrillar amyloidogenic LC may allow halting or even reverting damage in target sites. This review recapitulates the current knowledge and the most recent acquisitions regarding the mechanisms of organ damage in AL amyloidosis, with special emphasis on the heart, and will provide a critical discussion on possible novel treatment targets.

Beyond Survival in AL amyloidosis: Identifying and Satisfying Patients’ Needs

The survivorship needs of patients with light-chain (AL) amyloidosis are complex, as is the diagnosis and treatment itself. Early diagnosis is critical in improving patient outcomes; however, given the nonspecific nature of the symptoms, most patients with AL amyloidosis require evaluation by multiple specialists, resulting in significant delays in diagnosis of up to 3 years. An early and accurate diagnosis can help reduce the psychological toll of the patient’s journey to diagnosis. Given the high symptom burden and complex process of diagnosis, it is not surprising that patients with AL amyloidosis report worse health-related quality of life than the general population. Organ dysfunction associated with AL amyloidosis also may make the treatment directed towards plasma cell clone difficult to tolerate, leading to morbidity and mortality. Furthermore, supportive care requires an integrated, multidimensional and patient-centered approach to improve survival and feelings of well-being, as organ responses lag behind hematologic responses. The impact of AL amyloidosis is often devastating for the patient and may last beyond the effects of treatment. Future research is needed to study and assess the needs of survivors of AL amyloidosis utilizing valid, reliable and standardized measures.

Learning from Patients: The Interplay between Clinical and Laboratory Research in AL Amyloidosis

Primary systemic light chain amyloidosis (AL) is a rare monoclonal plasma cell disorder. Much research has been performed to determine the factors that underly amyloidogenicity. However, there is increasing evidence that the primary clone, and also patient-related factors, influence the mechanism and rate of the process. The lessons learnt from patient care definitely imply that this is not solely due to the deposition of material in the tissues that cause organ injury but amyloid light chain precursors are likely to mediate cellular toxicity. The disease rarity, combined with the lack of in vitro tools, and that multi-organ failure has a wide clinical spectrum, result in investigative challenges and treatment limitations (due to AL patient frailty). All these characteristics make the disease difficult to diagnose and indicate the need to further study its origins and treatments. This review will focus on the various aspects of the amyloidogenic plasma cell clone, as learnt from the patient care and clinics, and its implications on basic as well as clinical trials of AL research. Details regarding the etiology of the plasma cell clone, understanding the diagnosis of AL, and improvement of patient care with specific consideration of the future perspectives of individualized patient therapy will be described.

Molecular Mechanisms of Cardiac Amyloidosis

Cardiac involvement has a profound effect on the prognosis of patients with systemic amyloidosis. Therapeutic methods for suppressing the production of causative proteins have been developed for ATTR amyloidosis and AL amyloidosis, which show cardiac involvement, and the prognosis has been improved. However, a method for removing deposited amyloid has not been established. Methods for reducing cytotoxicity caused by amyloid deposition and amyloid precursor protein to protect cardiovascular cells are also needed. In this review, we outline the molecular mechanisms and treatments of cardiac amyloidosis.

Diseases with major salivary glands enlargement and orbits, nose and paranasal sinuses lesions in the practice of a rheumatologist

Objective: to analyze the nosological spectrum, demographic, clinical and laboratory characteristics of diseases with a significant enlargementof major salivary (SG) / lacrimal glands, and/or accessory organs of the eye and paranasal sinuses lesions in rheumatological practice.Patients and methods. This work includes 73 patients who underwent a complex clinical and laboratory, imaging, pathomorphological and histomolecular examination, which was necessary to establish a nosological diagnosis. In all cases, the diagnosis was confirmed pathomorphologically.Results and discussion. Sjogren's syndrome (SjS) was diagnosed in 30 (41%) patients (14 of them developed lymphoproliferative disorder, LPD, as a complication), granulomatosis with polyangiitis (GPA) – in 12 (16.4%), IgG4-related disease (IgG4-RD) – in 10 (13.7%), sarcoidosis – in 6 (8.2%), non Langerhans cell histiocytosis – in 2 (2.7%), AL-amyloidosis – in 1 (1.4%), Warthin's tumor – in 1 (1.4%), chronic atrophic rhinitis – in 1 (1.4%), infectious lesions – in 3 (4.1%) (HIV-associated – in 2, dirofilariasis – in 1), idiopathic inflammatory pseudotumor – in 6 (8.2%). In 1 (1.4%) patient, the diagnosis could not be established.A massive increase of major SG was observed in 46 patients, more often (in 28 cases) with SjS with LPD or without it, with IgG4-RD (in 7) and sarcoidosis (in 6). Orbital lesions were observed in 18 patients: in 7 with IgG4-RD, in 5 with idiopathic inflammatory pseudotumor, in 2 with sarcoidosis, in 2 with GPA, and in 1 each with non Langerhans cell histiocytosis and dirofilariasis. Nasal lesions in the form of chronic rhinosinusitis with or without nasal septum perforation, were found in 18 patients, 12 of whom suffered GPA and 6 – IgG4-RD.Two algorithms, that can facilitate the choice of additional studies and the direction of diagnostic search have been proposed for practicing rheumatologists.Conclusion. Taking into account the possible similarity of clinical manifestations of the diseases with the formation of mass-like tissue, the differential diagnosis should be based on pathomorphological study.

AL amyloidosis: untangling new therapies

Systemic light chain (AL) amyloidosis is a protein misfolding disorder characterized by the deposition of abnormal immunoglobulin light chains in fibrillary aggregates, resulting in end-organ damage. Several unique challenges face treating physicians, including delayed diagnosis, advanced vital organ involvement, and morbidity with treatment. Aggressive supportive care and risk-adapted application of plasma cell–directed therapies are the cornerstones of management. The therapeutic revolution in multiple myeloma will likely further expand the arsenal against plasma cells. Careful investigation of these agents will be critical to establish their role in this fragile population. The promise of fibril-directed therapies to restore organ function remains despite early disappointments. In this review, we discuss new therapies to tackle AL amyloidosis using a case-based approach.

Treatment in AL Amyloidosis: Moving towards Individualized and Clone-Directed Therapy

Systemic amyloid light chain (AL) amyloidosis is a rare protein deposition disease caused by a clonal B cell disorder of the bone marrow. The underlying diseases can be plasma cell disorders (monoclonal gammopathy of clinical significance, smoldering or symptomatic myeloma) or B cell non-Hodgkin’s lymphoma (e.g., Waldenstrom’s disease or marginal zone lymphoma) with secretory activity. It is crucial to characterize the underlying disease very precisely as the treatment of AL amyloidosis is directed against the (often small) B cell clone. Finally, the detection of cytogenetic aberrations of the plasma cell clone will likely play an important role for choosing an effective drug in the near future.