Kidney Biopsy in Patients With Monoclonal Gammopathy: A Multicenter Retrospective Cohort Study

Objectives: To analyze the clinical characteristics and renal pathological manifestations of patients with monoclonal gammopathy (MG) and kidney injury. Methods: This was a multicenter retrospective cohort study conducted at four tertiary hospitals in China. The study population comprised patients with MG admitted from January 1 2013 to December 31 2020. Hospitalization records, laboratory data, and kidney biopsy reports of all patients were collected from the electronic hospital information systems. The study outcomes included kidney disease progression and major hemorrhagic complications after kidney biopsy. Results: We identified 1,164 patients with MG, 782 (67.2%) of whom had underlying kidney injury. Of 101 patients who underwent kidney biopsy, 16 had malignant neoplasms. Amyloid nephropathy was the most common finding (n = 34, 33.7%), followed by membranous nephropathy (n = 18, 17.8%) and membranoproliferative nephritis (n = 8, 7.9%). Among 85 patients with non-malignant hematologic conditions who underwent kidney biopsy, 43 had MG of renal significance (MGRS) related lesions and 42 had MG-unrelated lesions. The risk of kidney disease progression was higher in patients with kidney injury than in patients without kidney injury. Conclusion: Among patients with MG and kidney injury, only 12.9% underwent kidney biopsy and more than 40% of these patients had MG-unrelated lesions. A kidney biopsy is safe and essential to maximize the possibility of correct diagnosis for patients with clinically suspected MG of renal significance (MGRS).

A Fresh Perspective on Monoclonal Gammopathies of Renal Significance

Monoclonal gammopathies of renal significance (MGRS) encompass a remarkable variety of kidney diseases that result from intrinsic nephrotoxic properties of certain monoclonal Igs or their subunits. Effective disease-modifying treatments rely on the targeting of a malignant B-cell clone that may be demonstrable but often is quite hypothetical. Hence, convincing arguments for the genuine monoclonal character of the causative mono-isotypic Ig tissue deposits is needed for design of appropriate treatment strategies. The purpose of this article was to critically analyze distinct situations of suspected MGRS that occur in the practice of pathologists, nephrologists, hematologists, and immunologists. A particular focus of interest is the group of conditions known as proliferative glomerulonephritis with mono-isotypic immunoglobulin deposits (PGNMIDs), which illustrates the difficulties and ambiguities surrounding a definitive assignment of MGRS status.

In vitro diagnostics for the medical dermatologist. Part II: Hypercoagulability tests

The skin often provides initial clues of hypercoagulability with features such as livedo reticularis, livedo racemosa, retiform purpura, necrosis, and ulcerations. Because these cutaneous manifestations are nonspecific, laboratory testing is often needed to evaluate for underlying causes of hypercoagulability. Importantly, these disorders are reported to be the most common mimicker, resulting in an erroneous diagnosis of pyoderma gangrenosum. Understanding inherent properties of, and indications for, available tests is necessary for appropriate ordering and interpretation of results. Additionally, ordering of these tests in an indiscriminate manner may lead to inaccurate results, complicating the interpretation and approach to management. This second article in this continuing medical education series summarizes information on methodology, test characteristics, and limitations of several in vitro laboratory tests used for the work up of hypercoagulability and vasculopathic disease as it pertains to dermatologic disease.

Diagnostic performance of routine electrophoresis and immunofixation for the detection of immunoglobulin paraproteins (M-Proteins) in dogs with multiple myeloma and related disorders: Part 2-Toward improved diagnostic performance

BACKGROUND

The diagnostic performance of routine electrophoresis (agarose gel electrophoresis [AGE] and capillary zone electrophoresis [CZE]) and species-specific immunofixation (IF) for the detection of immunoglobulin paraproteins (M-proteins) and diagnosis of secretory myeloma-related disorders (sMRD) can be improved. Available canine IF targets were IgG-FC, IgA, IgM, light chain (LC), IgG4, and free LC (fLC) antibodies.

OBJECTIVE

We aimed to review specific features associated with the presence of M-proteins in canine serum samples and the common features causing inaccurate reporting of M-proteins to improve the diagnostic performance of routine electrophoresis and IF for the detection of M-proteins.

METHODS

Features found in AGE, CZE, routine IF, IgG4 IF, and fLC IF of 100 canine serum samples from Part 1 of this study were evaluated by simple and multivariate logistic regression to identify factors associated with the presence of M-proteins. Cases falsely called negative or positive for M-proteins were reviewed to identify the common features that could be used to increase the diagnostic performance of SPE and IF for M-protein detection.

RESULTS

The presence of hypogammaglobulinemia or any peak taller than albumin was associated with an M-protein. Total protein concentrations, globulin concentrations, or peaks wider than albumin were not associated with an M-protein. Free LC sMRD cases were not diagnosed by SPE and routine IF. Cases with infectious and inflammatory etiologies had a restricted polyclonal gammopathy with multiple γ-globulin restrictions resulting in some false-positive results. SPE combined with all available IF results and the specific features identified in this study had an estimated sensitivity of 95.1% and specificity of 81.4%.

CONCLUSIONS

The identified criteria of this study increase the diagnostic performance of the electrophoretic evaluation for M-proteins.

Diagnostic performance of routine electrophoresis and immunofixation for the detection of immunoglobulin paraproteins (M-Proteins) in dogs with multiple myeloma and related disorders: Part 1 - Current performance

BACKGROUND

Routine electrophoresis [agarose gel electrophoresis (AGE) and capillary zone electrophoresis (CZE)] and species-specific immunofixation (IF) can be used alone or in combination to detect immunoglobulin paraprotein (M-protein) and diagnose secretory myeloma-related disorders (sMRD).

OBJECTIVE

We aimed to evaluate the performance of AGE, CZE, CZE plus IF (CZE-IF), and AGE plus IF (AGE-IF) for detecting canine serum M-proteins.

METHODS

One hundred canine cases that had AGE, CZE, and routine IF performed on serum, and where B-cell lineage neoplasia (such as B-cell lymphoma and plasma cell tumors) had been diagnosed or excluded, were evaluated. Routine IF protocols targeted IgG-FC, IgA, and IgM heavy chains and light chains. IgG4 IF and free light chain IF were also performed. B-cell lineage neoplasms with an M-protein detected, using any available method, were classified as sMRD. Datasets from AGE, CZE, IF, CZE-IF, and AGE-IF (electrophoretograms, gel images, and fraction concentrations) were composed and reviewed. The sensitivity, specificity, and Youden's index for M-protein detection were determined for each dataset.

RESULTS

The combination of AGE-IF or CZE-IF was more sensitive (82.9%) than CZE alone (72.0%) or AGE alone (64.6%) and more specific (66.1%, 48.3%, 51.7%, respectively). Immunofixation could be used alone to detect M-proteins (sensitivity 82.9%, specificity 61.9%), but there were technical challenges that complicated the performance and evaluation of the test. Myeloma with free light chains only was found in 5/41 cases of sMRD.

CONCLUSIONS

Adding routine IF to routine electrophoresis increases the ability to accurately identify M-proteins; however, there is still room for further diagnostic performance improvements.

The Clone Wars: Diagnosing and Treating Dysproteinemic Kidney Disease in the Modern Era

Dysproteinemic kidney diseases are disorders that occur as the result of lymphoproliferative (B cell or plasma cell) disorders that cause kidney damage via production of nephrotoxic monoclonal immunoglobulins or their components. These monoclonal immunoglobulins have individual physiochemical characteristics that confer specific nephrotoxic properties. There has been increased recognition and revised characterization of these disorders in the last decade, and in some cases, there have been substantial advances in disease understanding and treatments, which has translated to improved patient outcomes. These disorders still present challenges to nephrologists and patients, since they are rare, and the field of hematology is rapidly changing with the introduction of novel testing and treatment strategies. In this review, we will discuss the clinical presentation, kidney biopsy features, hematologic characteristics and treatment of dysproteinemic kidney diseases.

The Role of Light Kappa and Lambda Chains in Heart Function Assessment in Patients with AL Amyloidosis

There are reports indicating that myocardial dysfunction in systemic immunoglobulin light chain amyloidosis (AL amyloidosis) stems not only from the amyloid deposit in the organ but also the cardiotoxicity of the amyloid precursor free light chains (FLCs) circulating in the blood. The aim of the study is to analyze the role of sFLC κ and λ in the assessment of heart involvement and the degree of myocardial damage in AL amyloidosis. The study involved 71 patients diagnosed with primary AL amyloidosis. The relationship between sFLC concentrations and cardiac biochemical and echocardiographic parameters was assessed. The median concentrations of N-terminal pro b-type natriuretic peptide(NT-proBNP) and troponin I (TnI) were significantly higher in patients with amyloids formed from monoclonal λ chains compared to patients with monoclonal κ proliferation. In patients with heart involvement by amyloids formed from monoclonal FLC, the study demonstrated a statistically significant positive correlation between the concentration of monoclonal antibody λ chain and TnI (R = 0.688; p < 0.05), NT-proBNP (R = 0.449; p < 0.05), and the value of diastolic dimension of the interventricular septum (IVS; R = 0.496, p < 0.05). The above data indicate that the presence of monoclonal λ chains in patients with AL amyloidosis may be associated with more severe damage to cardiomyocytes and dysfunction of the myocardium.

Multiple Myeloma and Vasculitic Neuropathy: An Unusual Presentation

Multiple myeloma (MM) is a clonal proliferation of plasma cells in the bone marrow resulting in the production of paraproteins. It is more common in elderly adults and presents with nonspecific symptoms like bone pain, pathological fracture, fatigue, and signs of hypercalcemia. Peripheral neuropathy is an atypical presentation. We present a rare case of vasculitic neuropathy (VN) who was also diagnosed with MM at the same time. Nerve conduction study and biopsy showed findings suggestive of demyelinating VN. His serum protein electrophoresis and bone marrow aspirate were consistent with MM. The association between these two conditions remains understudied. So far there is no strong evidence suggesting an association between MM and VN. If VN was just coincidental or a presenting symptom of MM remains a question and warrants further studies.

Randall-Type Monoclonal Immunoglobulin Deposition Disease: New Insights into the Pathogenesis, Diagnosis and Management

Randall-type monoclonal immunoglobulin deposition disease (MIDD) is a rare disease that belongs to the spectrum of monoclonal gammopathy of renal significance (MGRS). Renal involvement is prominent in MIDD, but extra-renal manifestations can be present and may affect global prognosis. Recent data highlighted the central role of molecular characteristics of nephrotoxic monoclonal immunoglobulins in the pathophysiology of MIDD, and the importance of serum free light chain monitoring in the diagnosis and follow-up disease. Clone-targeted therapy is required to improve the overall and renal survival, and the achievement of a rapid and deep hematological response is the goal of therapy. This review will focus on the recent progress in the pathogenesis and management of this rare disease.

Comparison of Monoclonal Gammopathies Linked to Poliovirus or Coxsackievirus vs. Other Infectious Pathogens

Chronic stimulation by infectious pathogens or self-antigen glucosylsphingosine (GlcSph) can lead to monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma (MM). Novel assays such as the multiplex infectious antigen microarray (MIAA) and GlcSph assays, permit identification of targets for >60% purified monoclonal immunoglobulins (Igs). Searching for additional targets, we selected 28 purified monoclonal Igs whose antigen was not represented on the MIAA and GlcSph assays; their specificity of recognition was then analyzed using microarrays consisting of 3760 B-cell epitopes from 196 pathogens. The peptide sequences PALTAVETG and PALTAAETG of the VP1 coat proteins of human poliovirus 1/3 and coxsackievirus B1/B3, respectively, were specifically recognized by 6/28 monoclonal Igs. Re-analysis of patient cohorts showed that purified monoclonal Igs from 10/155 MGUS/SM (6.5%) and 3/147 MM (2.0%) bound to the PALTAVETG or PALTAAETG epitopes. Altogether, PALTAV/AETG-initiated MGUS are not rare and few seem to evolve toward myeloma.

External quality assessment of M-protein diagnostics: a realistic impression of the accuracy and precision of M-protein quantification

OBJECTIVES

Studies that investigate the accuracy and precision of M-protein quantification are scarce. These studies are prone to give a biased view, since they are exclusively performed by institutions with international top-expertise on M-protein diagnostics. To obtain a realistic impression of the accuracy and precision of M-protein quantification, we studied results of 73 laboratories participating in the Dutch External Quality Assessment (EQA) program for M-protein diagnostics.

METHODS

To measure accuracy, healthy serum was spiked with respectively 1 and 5 g/L human IgG-kappa monoclonal antibody daratumumab. To measure precision, five sera were selected to be repeatedly send to all blinded EQA-participants.

RESULTS

The reported concentrations for the EQA-sample spiked with 5 g/L daratumumab ranged from 2.6 to 8.0 g/L (mean 4.9 g/L, between-laboratory CV = 23%). 98% of the participants detected and correctly characterized the 1 g/L daratumumab band. Both the accuracy (mean 1.7 g/L) and precision (between-laboratory CV = 46%) of this 1 g/L M-protein was poor. In the five EQA-samples that were repeatedly send to the same 73 participating laboratories, between-laboratory precision (mean CV = 25%) was significantly different than the within-laboratory precision (mean CV = 12%). Relatively poor precision was observed in sera with small M-proteins.

CONCLUSIONS

The EQA-data reveal a large variation in reported M-protein concentrations between different laboratories. In contrast, a satisfactory within-laboratory precision was observed when the same sample was repeatedly analyzed. The M-protein concentration is correlated with both accuracy and precision. These data indicate that M-protein quantification to monitor patients is appropriate, when subsequent testing is performed within the same laboratory.

Mechanisms of Nerve Damage in Neuropathies Associated with Hematological Diseases: Lesson from Nerve Biopsies

Despite the introduction of non-invasive techniques in the study of peripheral neuropathies, sural nerve biopsy remains the gold standard for the diagnosis of several neuropathies, including vasculitic neuropathy and neurolymphomatosis. Besides its diagnostic role, sural nerve biopsy has helped to shed light on the pathogenic mechanisms of different neuropathies. In the present review, we discuss how pathological findings helped understand the mechanisms of polyneuropathies complicating hematological diseases.

Renal Expression of Light Chain Binding Proteins

Overproduction of human light chains (LCs) and immunoglobulins can result in various forms of renal disease such as cast nephropathy, monoclonal immunoglobulin deposition disease, LC proximal tubulopathy, AL amyloidosis, and crystal storing histiocytosis. This is caused by cellular uptake of LCs and overwhelmed intracellular transport and degradation in patients with high urine LC concentrations. LC kappa and lambda purification was evaluated by sodium dodecyl sulfate gel electrophoresis. LC and myeloma protein binding to immobilized renal proteins was measured by enzyme-linked immunosorbent assay (ELISA). The human protein microarray (HuProt™) was screened with purified kappa and lambda LC. Identified LC partners were subsequently analyzed in silico for renal expression sites using protein databases, Human Protein Atlas, UniProt, and Bgee. Binding of urinary LCs and immunoglobulins to immobilized whole renal proteins from 22 patients with myeloma or plasma cell dyscrasia was shown by ELISA. Forty lambda and 23 kappa interaction partners were identified from HuProt™ array screens, of which 21 were shared interactors. Among the total of 42 interactors, 12 represented cell surface proteins. Lambda binding signals were approximately 40% higher than kappa signals. LC interaction with renal cells and disease-causing pathologies are more complex than previously thought. It involves an extended spectrum of proteins expressed throughout the nephron, and their identification has been enabled by recently developed methods of protein analysis such as protein microarray screening. Further biochemical studies on interacting proteins are warranted to elucidate their clinical relevance.

Complete remission of necrobiotic xanthogranuloma after disappearance of monoclonal immunoglobulin induced by bortezomib, lenalidomid and dexamethasone

Necrobiotic xanthogranuloma (NXG) is a rare chronic condition, belonging to the group non-Langerhans cell histiocytoses, which is relevant due to the possibility of extracutaneous involvement and association with systemic diseases, particularly monoclonal gammopathy, MGUS and multiple myeloma. The case reported here NXG was diagnosed after 1 years of evolution in patient with asymptomatic multiple myeloma. After treatment with bortezomib, lenalidomid and dexamethasone, there was evident abrupt decrease of monoclonal immunoglobulin to not measurable level (complete remission of multiple myeloma) and in the same time was evident disappearance of cutaneous and hepatic lesions of NXG on FDG-PET/CT. The etiopathogenetic association of monoclonal immunoglobulin with NXG is documented in this case report with disappearance of NXG in the time of disappearance of monoclonal immunoglobulin.

Recurrent Glomerulonephritis in the Kidney Allograft

Renal transplantation is the preferred form of renal replacement therapy in patients who develop end-stage kidney disease (ESKD). Among the diverse etiologies of ESKD, glomerulonephritis is the third most common cause, behind hypertensive and diabetic kidney disease. Although efforts to prolong graft survival have improved over time with the advent of novel immunosuppression, recurrent glomerulonephritis remains a major threat to renal allograft survival despite concomitant immunosuppression. As a result, clinical expertise, early diagnosis and intervention will help identify recurrent disease and facilitate prompt treatment, thus minimizing graft loss, resulting in improved outcomes. In this review, we highlight the clinicopathologcal characteristics of certain glomerular diseases that recur in the renal allograft.

Schnitzler Syndrome in a 27-Year-Old Man: Diagnostic and Therapeutic Dilemma in Adult Auto-Inflammatory Syndromes A Case Report and Literature Review

A 32-year-old-man, with a history of chronic urticaria from the age of 27, diagnosed with an adult-onset Still’s disease and received a low dose of glucocorticoids, methotrexate and tocilizumab. Despite the long-term combined treatments, he suffered from chronic urticaria, low-grade fever and bone pain. He was found to have high inflammatory markers, hypogammaglobulinemia, monoclonal IgM – kappa light chain in serum and increased radiotracer uptake in the whole bone scintigraphy. No pathological variants for monogenic autoinflammatory diseases were present in the genome exome sequencing. These investigations confirmed the diagnosis of Schnitzler syndrome, which is an exception before the age of 35. Switching from tocilizumab to interleukin 1 receptor inhibitor, anakinra led to a full clinical response and normalisation of inflammatory markers. Patients with a history of fever and chronic urticaria are routinely tested for monoclonal gammopathy in the context of malignancy, but it should also be considered as a sign of the autoinflammatory syndrome. The Schnitzler syndrome and the adult-onset Still’s disease share common features, so the diagnosis requires a thorough investigation to establish an optimal treatment. In the diagnostic algorithm, monoclonal gammopathy is usually considered red flag for malignancy but might be overlooked as a criterion of Schnitzler syndrome, particularly in young adults. We confirm that the interleukin 1 inhibitor should be the first line of therapy in Schnitzler syndrome, and in the presented case we found it more effective than the interleukin 6 blockade. The main goal of this paper is to increase awareness of Schnitzler syndrome among health care professionals. We aim to present features which can be helpful in differential diagnosis.

Epstein-Barr Virus and Monoclonal Gammopathy of Clinical Significance in Autologous Stem Cell Transplantation for Multiple Sclerosis

INTRODUCTION

Autologous hematopoietic stem cell transplantation (AHSCT) with anti-thymocyte globulin (ATG) conditioning as treatment of active multiple sclerosis (MS) is rapidly increasing across Europe (EBMT registry data 2017). Clinically significant Epstein-Barr virus reactivation (EBV-R) following AHSCT with ATG for severe autoimmune conditions is an underrecognized complication relative to T-cell deplete transplants performed for hematological diseases. This retrospective study reports EBV-R associated significant clinical sequelae in MS patients undergoing AHSCT with rabbit ATG.

METHODS

Retrospective data were analyzed for 36 consecutive MS-AHSCT patients at Kings College Hospital, London. All patients routinely underwent weekly EBV DNA polymerase chain reaction monitoring and serum electrophoresis for monoclonal gammopathy (MG or M-protein). EBV-R with rising Epstein-Barr viral load, M-protein, and associated clinical sequelae were captured from clinical records.

RESULTS

All patients had evidence of rising EBV DNA-emia, including 7 who were lost to long-term follow-up, with a number of them developing high EBV viral load and associated lymphoproliferative disorder (LPD). Nearly 72% (n = 18/29) developed de novo MG, some with significant neurological consequences with high M-protein and EBV-R. Six patients required anti-CD20 therapy (rituximab) with complete resolution of EBV related symptoms. Receiver operating characteristics estimated a peak EBV viremia of >500 000 DNA copies/mL correlated with high sensitivity (85.5%) and specificity (82.5%) (area under the curve: 0.87; P = .004) in predicting EBV-R related significant clinical events.

CONCLUSION

Symptomatic EBV reactivation increases risk of neurological sequelae and LPD in MS-AHSCT. We recommend regular monitoring for EBV and serum electrophoresis for MG in MS patients in the first 3 months post-AHSCT.

Increased Risk of Cutaneous Diseases in Multiple Myeloma Patients

Introduction

Multiple myeloma (MM) is a monoclonal gammopathy characterized by malignant proliferation of plasma cells in the bone marrow, leading to the overproduction of monoclonal immunoglobulins. Knowledge of cutaneous findings associated with multiple myeloma is limited. This study aims to characterize cutaneous manifestations in patients with MM or monoclonal gammopathy of undetermined significance (MGUS).

Methods

This is a retrospective study of patients seen at a single institution between January 2000 and January 2019 with a diagnosis of “multiple myeloma,” “monoclonal gammopathy of undetermined significance,” or “smoldering myeloma,” and an on-site dermatology clinic visit.

Results

Twenty patients met the inclusion criteria. Most patients were male and Caucasian. Comorbid cutaneous malignancies were noted in 65% of patients (n = 13). Basal cell carcinoma (BCC) was characterized in 55% of patients (n = 11), followed by squamous cell carcinoma in 50% of patients (n = 10), and melanoma in 10% of patients (n = 2).

Conclusions

Patients with monoclonal gammopathy may be predisposed to developing cutaneous malignancies and skin infections. Given the low prevalence of monoclonal gammopathy, larger multi-center studies with a control cohort may be necessary to delineate the significance of these comorbid skin conditions.

Immunotactoid glomerulopathy is a rare entity with monoclonal and polyclonal variants

Immunotactoid glomerulopathy (ITG) is a rare form of glomerulonephritis for which our understanding is limited to case reports and small case series. Herein we describe the clinical, pathologic, and outcome characteristics of 73 patients with ITG who typically presented with proteinuria, hematuria, and renal insufficiency. Hematologic disorders were present in 66% of patients, including lymphoma in 41% (mainly chronic lymphocytic leukemia/small lymphocytic lymphoma), monoclonal gammopathy in 20%, and multiple myeloma in 6%. Light microscopy revealed endocapillary proliferative (35%), membranoproliferative (29%) and membranous (29%) patterns of glomerular involvement. Electron microscopy revealed characteristic microtubular deposits with a diameter of 14-60 nm, hollow cores, frequent parallel alignment, and a predominant distribution outside of the lamina densa of the glomerular basement membrane. Importantly, immunofluorescence revealed IgG-dominant staining which was light chain and IgG subclass restricted in 67% of cases, indicating monoclonal composition. This finding was used to distinguish monoclonal and polyclonal variants of ITG. As compared to polyclonal, monoclonal ITG had a higher incidence of lymphoma (53% vs. 11%), multiple myeloma (8% vs. 0), and monoclonal gammopathy (22% vs. 16%). Monoclonal ITG was more commonly treated with clone-directed therapy, which was associated with more frequent remission and less frequent end stage kidney disease. Thus, a third of ITG cases are polyclonal but a quarter of these cases are associated with hematologic conditions, underscoring the need for hematologic evaluation in all patients with ITG. Hence, based on these distinctions, ITG should be subclassified into monoclonal and polyclonal variants. Prognosis of ITG is good if the underlying hematologic condition is treated.

Ocular manifestation of giant cell arteritis vs AL-amyloidosis: similar presentations but different approaches

Light chain (AL) amyloidosis may present with the features of vasculitis, including giant cell arteritis (GCA). Similarities between GCA and AL-amyloidosis can potentially cause confusion in diagnosis, in which case, temporal artery biopsy (TAB) should be performed to make a definitive diagnosis. Herein we report a case of a bilateral anterior ischaemic optic neuropathy (AION), showing evidence of AL-amyloidosis on the temporal artery biopsy. A 75-year-old male with AL-amyloidosis secondary to monoclonal gammopathy of undetermined significance (MGUS) presented to our hospital for subacute painless progressive visual impairment. Based on his elevated inflammatory markers and his age, he was suspected to have giant cell arteritis. However, a temporal artery biopsy excluded GCA, and the Congo red staining was positive for amyloid deposition. This present case reveals that AL-amyloidosis may present with visual impairment, high inflammatory markers, and involvement of temporal arteries, concerning for GCA. TAB with Congo red staining is found to be crucial for making the correct diagnosis.

From pathogenesis to personalized treatments of neuropathies in hematological malignancies

The peripheral nervous system may be involved at any stage in the course of several hematological diseases, the most common being monoclonal gammopathies (of undetermined significance or malignant) or lymphomas. The underlying pathogenic mechanisms are different and therapies aim at targeting the dangerous either B-cell or plasma cell clones. Recently, high-throughput technologies, and next-generation sequencing have increased our knowledge of hematological diseases pathogenesis by the identification of somatic mutation affecting pivotal signaling pathways. Accordingly, new target therapies are used that may also be borrowed for treatment of neuropathies in hematological diseases.