The cryoglobulinaemias

Post-Treatment Occurrence of Serum Cryoglobulinemia in Chronic Hepatitis C Patients

BACKGROUND

Persistent cryoglobulinemia after the completion of antiviral treatment is an important consideration of clinical management in chronic hepatitis C patients. We aimed to investigate the occurrence of serum cryoglobulinemia in chronic hepatitis C patients without cryoglobulinemia at the initiation of antiviral treatment.

METHODS

In total, 776 patients without cryoglobulinemia were assessed for serum cryoglobulinemia after the completion of anti-HCV treatment. Serum cryoglobulinemia precipitation was assessed upon both the initiation and the completion of the treatment and analyzed for the clinical laboratory factors associated with chronic hepatitis C.

RESULTS

One hundred eighteen (118) patients were checked for serum cryo-precipitation after the completion of the treatment, and eight patients (4.6%) were positive for serum cryoglobulinemia. The patients who tested positive for cryoglobulinemia included a higher proportion of liver cirrhosis patients (4/50%, p = 0.033) and other organ cancer patients (5/62.5%, p = 0.006) than patients who showed no signs of cryoglobulinemia after treatment. In a multivariate analysis, liver cirrhosis (odds ratio [OR]-17.86, 95% confidence interval [95% CI]-1.79-177.35, p = 0.014) and other organ cancer (OR-25.17 95% CI-2.59-244.23, p = 0.005) were independently and significantly associated with positive cryoglobulinemia 3 months after antiviral treatment.

CONCLUSIONS

Three months after the antiviral DAA therapy had concluded, eight patients tested positive for cryoglobulinemia, representing a 6.7% prevalence. Liver cirrhosis and other organ cancer were independently and significantly associated with positive cryoglobulinemia after antiviral treatment. Further investigation into the causes of positive cryoglobulinemia after DAA antiviral therapy is warranted.

Case report: BTK inhibitors is effective in type II mixed cryoglobulinemia with wild-type MyD88

This study presents two cases of type II mixed cryoglobulinemia. One case is essential, while the other is presumably associated with hepatitis B virus (HBV) infection. Both patients tested positive for monoclonal IgMκ, but negative for MyD88 mutation. They showed resistance to rituximab combined with a glucosteroid regimen, but responded positively to BTK inhibitors. These cases highlight the remarkable effectiveness of BTK inhibitors in treating refractory type II cryoglobulinemia without MyD88 mutation. The first patient achieved rapid complete remission of nephrotic syndrome within one month of starting ibrutinib, along with a significant reduction in cryoglobulin levels and abnormal clonal cells. The second patient had a rapid disappearance of rash within three days and accelerated wound healing within one week of initiating orelabrutinib, accompanied by a reduction in C-reactive protein. However, there was no reduction in cryoglobulin levels during the 12-month follow-up. These findings suggest varied mechanisms of action of BTK inhibitors in type II cryoglobulinemia through different mechanisms.

Clinical characteristics, radiological features and outcomes in pulmonary involvement of cryoglobulinemia

BACKGROUND

Cryoglobulinemia with pulmonary involvement is rare, and its characteristics, radiological findings, and outcomes are still poorly understood.

METHODS

Ten patients with pulmonary involvement of 491 cryoglobulinemia patients at Peking Union Medical College Hospital were enrolled in this retrospective study. We analyzed the characteristics, radiological features and management of pulmonary involvement patients, and compared with those of non-pulmonary involvement with cryoglobulinemia.

RESULTS

The 10 patients with pulmonary involvement (2 males; median age, 53 years) included three patients with type I cryoglobulinemia and seven patients with mixed cryoglobulinemia. All of 10 patients were IgM isotype cryoglobulinemia. All type I patients were secondary to B-cell non-Hodgkin lymphoma. Four mixed patients were essential, and the remaining patients were secondary to infections (n = 2) and systemic lupus erythematosus (n = 1), respectively. Six patients had additional affected organs, including skin (60%), kidney (50%), peripheral nerves (30%), joints (20%), and heart (20%). The pulmonary symptoms included dyspnea (50%), dry cough (30%), chest tightness (30%), and hemoptysis (10%). Chest computed tomography (CT) showed diffuse ground-glass opacity (80%), nodules (40%), pleural effusions (30%), and reticulation (20%). Two patients experienced life-threatening diffuse alveolar hemorrhage. Five patients received corticosteroid-based regimens, and four received rituximab-based regimens. All patients on rituximab-based regimens achieved clinical remission. The estimated two-year overall survival (OS) was 40%. Patients with pulmonary involvement had significantly worse OS and progression-free survival than non-pulmonary involvement patients of cryoglobulinemia (P < 0.0001).

CONCLUSIONS

A diagnosis of pulmonary involvement should be highly suspected for patients with cryoglobulinemia and chest CT-indicated infiltrates without other explanations. Patients with pulmonary involvement had a poor prognosis. Rituximab-based treatment may improve the outcome.

An Unusual Case of Cryoglobulinemic Vasculitis and Acute Disseminating Encephalomyelitis in a 21-Year-Old Caucasian Male

Cryoglobulinemic vasculitis and acute disseminated encephalomyelitis (ADEM) are characterized by damage to either blood vessels or grey matter. For both diseases, infections can be an etiology. In cryoglobulinemic vasculitis, the initial insult causes damage to the glomerulus, and in the case of ADEM, damage leads to a central nervous system demyelinating disorder. Infective endocarditis can be associated with both diseases and can be challenging to diagnose. Individuals on antibiotics may present with negative blood cultures, making underlying infective endocarditis difficult to diagnose. In this report, we describe a 21-year-old male who presented to the hospital after an assault with splenic laceration and was subsequently found to have infective endocarditis associated with cryoglobulinemic vasculitis and ADEM.

New Biomarkers for Systemic Necrotizing Vasculitides

Systemic necrotising vasculitides (SNVs) pose significant challenges due to their diverse clinical manifestations and variable outcomes. Therefore, identifying reliable biomarkers holds promise for improving precision medicine in SNVs. This review explores emerging biomarkers aiming to enhance diagnostic accuracy, prognostic assessment, and disease monitoring. We discuss recent advances in immunological biomarkers, inflammatory indicators, and other parameters that exhibit potential diagnostic and prognostic utility. A comprehensive understanding of these biomarkers may facilitate earlier and more accurate SNV detection, aiding in timely intervention and personalized treatment strategies. Furthermore, we highlight the evolving landscape of disease monitoring through innovative biomarkers, shedding light on their dynamic roles in reflecting disease activity and treatment response. Integrating these novel biomarkers into clinical practice can revolutionize the management of SNVs, ultimately improving patient outcomes and quality of life.

Insights into the immunological description of cryoglobulins with regard to detection and characterization in Slovenian rheumatological patients

The detection of cryoglobulins (CG) used to diagnose cryoglobulinemic vasculitis requires strict adherence to protocol, with emphasis on the preanalytical part. Our main objectives were to introduce a more sensitive and specific protocol for the detection of CG and to characterize CG in Slovenian patients diagnosed with cryoglobulinemic vasculitis, other vasculitides, connective tissue diseases or non-rheumatic diseases examined at the Department of Rheumatology (University Medical Centre Ljubljana). Samples were routinely analyzed for the presence of CG with the protocol using the Folin-Ciocalteu reagent. In the newly introduced protocol, the type of CG was determined by immunofixation on visually observed positive samples and the concentration of CG in the cryoprecipitate and rheumatoid factor (RF) activity were measured by nephelometry. RF, C3c and C4 were measured in patients` serum and a decision tree analysis was performed using all results. The agreement between negative and positive results between the two protocols was 86%. Of the 258 patient samples tested, we found 56 patients (21.7%) with positive CG (37.5% - type II, 62.5% - type III). The RF activity was observed in 21.4% of CG positive subjects. The median concentration of type II CG was significantly higher than that of type III CG (67.4 mg/L vs. 45.0 mg/L, p = 0.037). Patients with type II had lower C4 concentrations and higher RF compared to patients with type III CG. In the decision tree, C4 was the strongest predictor of cryoglobulinemia in patients. With the newly implemented protocol, we were able to improve the detection and quantification of CG in the samples of our rheumatology patients and report the results to adequately support clinicians.

Extrahepatic manifestations of HCV where do we stand?

Hepatitis C virus (HCV) infection has been associated as up 40-70% of patients with extrahepatic manifestations (EHM) and 36 different syndromes. These could be attributed to the fact that HCV is lymphotropic, particularly B lymphotropic, and not merely hepatotropic, and could trigger immunological alterations indirectly by exerting a chronic stimulus on the immune system with production of immunoglobulins having rheumatoid activity forming immune complexes and production of cryoglobulins. Cryoglobulinemoa plays a pivotal role in producing most EHM of HCV such as vasculitis, glomerulonephritis, arthritis and neuropathies. Less frequently; while less frequently, the direct viral cytopathic effect could lead to EHMs independent of cryoglobulinemia. The mainstay of treatment of EMH has been antivirals, since interferon era to direct-acting drugs era, with no differences between the two eras, despite the better virological response. Longer evaluation of virological response and clinical investigation with longer follow-ups are necessary.

Cryoglobulinemia vasculitis associated with adult-onset Still's disease

Key Clinical Message

The present case indicates that cryoglobulinemia vasculitis should be considered in the differential diagnosis of purpura in patients with adult-onset Still's disease (AOSD).

Abstract

The presence of purpura is suggested in adult-onset Still's disease (AOSD) hematological complications of hemophagocytic syndrome, disseminated intravascular coagulation, or thrombotic microangiopathy. We herein report a case of AOSD complicated by cryoglobulinemia vasculitis presenting with purpura.

Type 1 Cryoglobulinemic Vasculitis Due to Monoclonal Gammopathy of Undetermined Significance Successfully Treated by Bortezomib Plus Dexamethasone

Cryoglobulins are immunoglobulins that precipitate in cold conditions. Type I cryoglobulinemic vasculitis is associated with hematological malignancies. We herein report a case of steroid-resistant type 1 cryoglobulinemic vasculitis associated with monoclonal gammopathy of undetermined significance (MGUS) in a 47-year-old woman. By immunofixation of cryoglobulin, we found that the main component of cryoglobulin was the M protein due to MGUS, so treatment of MGUS was needed. Bortezomib+dexamethasone therapy resulted in a rapid decrease in cryoglobulin and improvement in the symptoms of cryoglobulinemic vasculitis. In refractory type I cryoglobulinemic vasculitis, treatment of the underlying gammaglobulinopathy should be considered.

Ocular manifestations of cryoglobulinemia: a reappraisal

BACKGROUND/OBJECTIVES

To describe frequency and type of ocular manifestations in patients with cryoglobulinemic vasculitis (CV), as well as management approaches and outcomes.

SUBJECTS/METHODS

This was a retrospective, observational, cohort study of patients who were diagnosed with CV at a single center and regularly underwent a comprehensive ocular assessment.

RESULTS

Ophthalmologic manifestations were recorded in 16 patients (28%). The diagnoses included dry eye disease and primary Sjögren syndrome in 5 and 2 patients, respectively; peripheral ulcerative keratitis and anterior scleritis in 1 patient each; hyperviscosity syndrome and hypertensive retinopathy in 2 patients each; and Purtscher- like retinopathy in 3 patients. Twelve patients (75%) were anti-HCV/HCV RNA-positive, 11 of whom achieved a sustained virologic response (SVR) following treatment with interferon-α2b plus ribavirin or direct-acting antivirals. All patients were treated with ocular lubricants. Systemic therapeutic measures, including glucocorticoids, immunosuppressive and biologic agents, induced the disappearance or ≥50% reduction of cryoglobulins and major signs of vasculitis in 11 patients (68.7%). In the remaining 5 patients (31.3%), cryoglobulins and CV manifestations remained unchanged or decreased by <50%. The corresponding ophthalmologic assessment showed a variable degree of improvement in the ocular symptoms in all but 2 patients (87.5%). The best corrected visual acuity following treatment improved in 26 eyes, was unchanged in 3 eyes, and worsened in 3 eyes.

CONCLUSIONS

Eye involvement is not a rare event in CV patients. A timely diagnosis and the correct employment of the available therapeutic measures may result in a favorable outcome of the ocular and extra-ocular manifestations.

[Secondary vasculitides]

Vasculitides that occur in association with underlying primary diseases are called secondary vasculitides. In the diverse differential diagnostics of vasculitides, a large variety of secondary vasculitides have to be considered. Secondary vasculitides cover the full spectrum of vasculitides, presenting in manifold clinical manifestations. This article provides an overview of systemic diseases and etiological factors, such as infections, drugs, and malignancies, which can be associated with vasculitides. The possible associations with infectious agents are too numerous to be comprehensively covered and are discussed in an exemplary fashion and with a western European focus. Especially in atypical and refractory disease courses, a secondary vasculitis should be considered. In light of the diversity of differential diagnoses and the particular challenges posed by secondary vasculitides, interdisciplinary collaboration is the key for an accurate and early diagnosis as well as for successful treatment management. Treatment of the primary disease should always be prioritized and, if a drug-induced vasculitis is suspected, immediate cessation of the culprit drug is mandatory.

Cryoglobulinemia: the "cold" problem in cardiac surgery, a single-center experience and a literature review

Cardiac surgery with cardiopulmonary bypass (CBP) is essential for different cardiac procedures in order to perform surgery with a clear sight field.To safely perform surgery with CPB and preserve brain, kidney, and patient tissue from ischemic damage, cold cardioplegia, and mild to deep hypothermia are induced during the operation.Cryoglobulinemia is a hematological/infective-related disease (in certain cases idiopathic) in which temperature-dependent antibodies tend to aggregate and form emboli in the vascular system causing tissue damage if exposed to low temperature.The patient with cryoglobulinemia (known and unknown) can be at risk of a major ischemic event during CPB and induced hypothermia.This article's aim is to evaluate the present scientific literature in order to understand how, in years, the therapeutic or preventive approach, is evolving, and to analyze and make improvements to the management of a cryoglobulinemic patient who must undergo elective or emergency cardiac surgery.In the last part of our article, we expose our single-center experience during a 32-month-long period of survey.In all cases, our medical team (anesthesiologists, perfusionists, and cardiac surgeons) opted for a normothermic cardiopulmonary bypass to lower the risk of cryoglobulin-associated complications.In our experience, along with therapeutic intervention to lower the cryoglobulin titer, normothermic management of cardiopulmonary bypass is as safe as hypothermic management.Notwithstanding our results, further studies with a larger population are needed to confirm this perioperative management in a cardiac surgery setting.

Cholestatic HCV Cryoglobulinemia: A New Clinical and Pathological Entity before and after Direct-Acting Antiviral Therapies-A Case-Control Study

Twenty-nine patients with HCV infection (HCV+) and mixed cryoglobulinemia (MC+) were retrospectively selected and matched for age and sex with 31 HCV+ MC- patients. Biomarkers of cholestasis (direct bilirubin, alkaline phosphatase, and gamma-glutamyl transferase), HCV-RNA and genotype, and plasma cryoprecipitates were measured before and after virus eradication; liver histology and plasma cells (aggregation and distribution), observed blinded by two pathologists, were analyzed. Sixty participants (mean age: 56.5; range: 35-77, males: 50%) with HCV infection were enrolled. Cholestasis (≥2 pathologically increased cholestasis biomarkers) was significantly higher in the MC group (p = 0.02) and correlated with cryoglobulinemia (OR 6.52; p = 0.02). At liver histological assessment, plasma cells were significantly increased in the MC+ group (p = 0.004) and tended to form aggregates more than the control group (p = 0.05). At multivariate analysis with MC, age, HCV-RNA, HBV diabetes, and cirrhosis, cholestasis was only significantly correlated to MC (OR 8.30; p < 0.05). In 25% patients, MC persisted after virus eradication with new antiviral treatment. Our study identified for the first time an association between MC, cholestasis, and an increased number of intrahepatic plasma cells in chronic hepatitis C (CHC) patients before virus eradication. Future studies are required to understand how MC contributes to liver damage and how its persistence affects the patients' follow-up after antiviral therapies.

Lupus nephritis with cryoglobulinemic glomerulonephritis features: a diagnostic conundrum

In this clinical case, we report an atypical and unique presentation of systemic lupus erythematosus (SLE) in a 39-year-old female with nephrotic syndrome. The patient exhibited class IV plus V lupus nephritis and extensive immune complex deposition within the intracapillary and arteriolar regions suggestive of cryoglobulinemic glomerulonephritis, despite no detectable circulating cryoglobulins. Electron microscopy revealed cryoglobulin-like deposit distribution in all glomerular examined compartments, namely subendothelial, intramembranous, subepithelial, and mesangial, apparently extending from the capillary hyaline thrombi. The case highlights the possibility of severe renal injury in SLE without circulating cryoglobulins and the diverse kidney manifestations associated with the disease. However, the impact on patient outcome was minimal, as classical treatment (id est National Institute of Health regimen) remained effective.

Efficacy of Therapeutic Apheresis for Cryoglobulinemic Vasculitis Patients with Renal Involvement: A Systematic Review

INTRODUCTION

Therapeutic apheresis (TA) is commonly used for cryoglobulinemic vasculitis (CV) patients, but its efficacy remains uncertain. This systematic review aimed to assess the efficacy of different TA modalities, such as plasma exchange (PE), plasmapheresis (PP), and cryofiltration (CF), in treating CV patients with renal involvement.

METHODS

Literature search of MEDLINE, EMBASE, and Cochrane Databases was conducted up to December 2022. Studies that reported the outcomes of TA in adult CV patients with renal involvement were assessed. The protocol for this systematic review has been registered with PROSPERO (No. CRD42023417727). The quality of each study was evaluated by the investigators using the validated methodological index for non-randomized studies (minors) quality score.

RESULTS

154 patients who encountered 170 episodes of serious events necessitating TA were evaluated across 76 studies. Among them, 51% were males, with a mean age ranging from 49 to 58 years. The CV types included 15 type I, 97 type II, and 13 type III, while the remaining patients exhibited mixed (n = 17) or undetermined CV types (n = 12). Among the treatment modalities, PE, PP, and CF were performed in 85 (56%), 52 (34%), and 17 patients (11%), respectively, with no identical protocol for TA treatment. The overall response rate for TA was 78%, with response rates of 84%, 77%, and 75% observed in type I, II, and III patients respectively. Most patients received steroids, immunosuppressants, and treatment targeting the underlying causative disease. The overall long-term renal outcome rate was 77%, with type I, II, and III patients experiencing response rates of 89%, 76%, and 90%, respectively. The renal outcomes in patients receiving PE, PP, and CF were comparable, with rates of 78%, 76%, and 81%, respectively.

CONCLUSIONS

This study presents compelling evidence that combination of TA with other treatments, especially immunosuppressive therapy, is a successful strategy for effectively managing severe renal involvement in CV patients. Among the TA modalities studied, including PE, PP, and CF, all demonstrated efficacy, with PE being the most frequently employed approach.

Hepatitis B virus-related cryoglobulinemia: Clinical characteristics, virological features, and treatment

BACKGROUND

Hepatitis B virus (HBV) infection is a rare etiology of cryoglobulinemia, and its clinical characteristics, virological features and treatment are poorly understood.

METHODS

This retrospective study enrolled 23 patients with HBV-related cryoglobulinemia from 497 cryoglobulinemia patients at Peking Union Medical College Hospital between January 2015 and February 2023. We analyzed the clinical characteristics, virological features and management of patients with HBV-related cryoglobulinemia.

RESULTS

The 23 patients (13 males; median age 48 years) were all mixed cryoglobulinemia and serological HBsAg positive, while 15 patients exhibited HBV-DNA replication. The presence of HBsAg in cryoglobulins was evaluated in 7 patients, all of whom were positive. The most commonly involved organs were kidneys (69.6%), skin (65.2%), peripheral nerves (21.7%), joints (8.7%), gastrointestinal tract (4.3%), and cardiac (4.3%). Eight patients received antiviral therapy with nucleot (s)ide analogues (NAs) alone, 12 patients received NA- and corticosteroid-based regimens, and 3 patients received NA- and rituximab-based regimens based on the severity of clinical symptoms. After a median follow-up of 44 months, four patients died, and one patient was lost to follow-up. All remaining patients (n = 18) achieved clinical remission, and HBV-DNA replication was not detected in 16 out of 18 patients. There was no HBV reactivation in patients treated with rituximab. The three-year overall survival and progression-free survival were 87.0% and 80.3%, respectively.

CONCLUSIONS

HBV-related cryoglobulinemia patients should be treated with antiviral therapy. Corticosteroids and rituximab are effective for severe cases, but patients need to be closely monitored for therapy-related infection.

Ocular complications of plasma cell dyscrasias

Plasma cell dyscrasias are a wide range of severe monoclonal gammopathies caused by pre-malignant or malignant plasma cells that over-secrete an abnormal monoclonal antibody. These disorders are associated with various systemic findings, including ophthalmological disorders. A search of PubMed, EMBASE, Scopus and Cochrane databases was performed in March 2021 to examine evidence pertaining to ocular complications in patients diagnosed with plasma cell dyscrasias. This review outlines the ocular complications associated with smoldering multiple myeloma and monoclonal gammopathy of undetermined significance, plasmacytomas, multiple myeloma, Waldenström's macroglobulinemia, systemic amyloidosis, Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal gammopathy and Skin changes (POEMS) syndrome, and cryoglobulinemia. Although, the pathological mechanisms are not completely elucidated yet, wide-ranging ocular presentations have been identified over the years, evolving both the anterior and posterior segments of the eye. Moreover, the presenting symptoms also help in early diagnosis in asymptomatic patients. Therefore, it is imperative for the treating ophthalmologist and oncologist to maintain a high clinical suspicion for identifying the ophthalmological signs and diagnosing the underlying disease, preventing its progression through efficacious treatment strategies.

Approach to laboratory ordering and interpretation in rheumatology

Evaluation of suspected rheumatic disease is a significant challenge due to overlapping and sometimes non-specific clinical features. Most laboratory tests in rheumatic disease have incomplete sensitivity and specificity, leading to positive results without disease and negative results despite disease presence. Therefore, judicious ordering and correct interpretation of laboratory testing in rheumatology is critical in order to provide high-value care. Herein we review laboratory testing in rheumatology in the context of a framework for approaching rheumatic disease.

Risk factors for relapse in non-infectious cryoglobulinemic vasculitis, including type I cryoglobulinemia: a systematic review

Background

Data on non-infectious cryoglobulinemic vasculitis (NICV) is scarce, especially concerning the management of relapses, which are troublesome. We aimed to investigate risk factors for relapse in NICV.

Methods

A systematic literature search of CINAHL, Embase, MEDLINE, Scopus, and the Web of Science databases was implemented until April 2023. Eligible studies included randomized control trials, observational studies, and case series with ≥4 patients. Two reviewers independently extracted data and assessed the quality of the eligible studies.

Results

A total of 3,724 articles were retrieved from a database search, with 27 studies meeting the inclusion criteria for review. Most studies (n = 23) detailed relapses, with the time to relapse varying between 1 and 80 months. The relapse rate was reported at 28% in Type I NICV and ranged from 22% to 60% in mixed NICV. Risk factors for relapse in NICV were identified based on the cryoglobulin subtype and correlated with clinical and immunological responses to varying treatment regimens. Type I NICV with an associated lymphoproliferative disorder exhibited a response-relapse pattern. Cutaneous and articular involvement and incomplete clinical and immunological responses to treatment, particularly corticosteroid monotherapy and occasionally rituximab, influence the risk of relapse in Type II and Type III NICV.

Conclusion

Our findings underscore the significance of attaining both clinical and immunological responses and identifying risk factors for relapse in NICV. Appropriate risk stratification for NICV patients is essential for the successful implementation of effective treatment strategies.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023408140.

Type II Cryoglobulinemic Membranoproliferative Glomerulonephritis Caused by Mucosa-associated Lymphoid Tissue Lymphoma

A 67-year-old man complained of lower limb edema with a purpuric skin rash. Laboratory tests revealed proteinuria, elevated serum creatinine levels, and low serum albumin levels. The patient was also positive for cryoglobulin in serum, immunoglobulin (Ig) M gammopathy, hypocomplementemia, and rheumatoid factor. He was negative for anti-hepatitis C virus antibodies. A pathological analysis of the renal tissue revealed membranoproliferative glomerulonephritis, common histological features of cryoglobulinemic vasculitis (CV), and mucosa-associated lymphoid tissue lymphoma invasion. Although hematologic malignancy is a rare cause of type II CV, these clinical findings suggest that mucosa-associated lymphoid tissue lymphoma (MALT) lymphoma may have been the cause in the present case.

The "Viral" Form of Polyarteritis Nodosa (PAN)-A Distinct Entity: A Case Based Review

Classic polyarteritis nodosa (PAN) is a vasculitis with systemic manifestations that is characterized by inflammatory and necrotizing lesions affecting medium and small muscular arteries, most frequently at the bifurcation of the vessels. These lesions lead to the formation of microaneurysms, hemorrhaging ruptured aneurysms, thrombosis, and, consequently, ischemia or organ infarction. Background and Objectives: We present a complex clinical case of a patient with a late diagnosis of polyarteritis nodosa with multiorgan involvement. Materials and Methods: The 44-year-old patient, in an urban environment, presented on her own in the emergency room for acute ischemia phenomena and forearm and right-hand compartment syndrome, requiring surgical decompression in the Plastic Surgery Clinic. Results: Significant inflammatory syndrome is noted, alongside severe normocytic hypochromic iron deficiency anemia, nitrogen retention syndrome, hyperkalemia, hepatic syndrome, and immunological disturbances: absence of cANCA, pANCA, anti Scl 70 Ac, antinuclear Ac, and anti dDNA Ac, as well as a low C3 fraction of the plasmatic complement system. The morphological aspect described in the right-hand skin biopsy correlated with the clinical data supports the diagnosis of PAN. Conclusions: The viral form of PAN seems to be individualized as a distinct entity, requiring early, aggressive medication.

CLEC18A Impairs Phagocytosis by Reducing FcγRIIA Expression and Arresting Autophagosome-Lysosome Fusion

Mixed cryoglobulinemia (MC) is a hepatitis C virus (HCV)-related extrahepatic manifestation that is characterized by the abnormal presence of immune complexes (ICs). This may be due to the reduced uptake and clearance of ICs. The C-type lectin member 18A (CLEC18A) is a secretory protein that is expressed abundantly in hepatocytes. We previously observed that CLEC18A increased significantly in the phagocytes and sera of patients with HCV, particularly those with MC. Herein, we explored the biological functions of CLEC18A in the MC syndrome development of patients with HCV by using an in vitro cell-based assay with quantitative reverse transcription-PCR, immunoblotting, immunofluorescence, flow cytometry, and enzyme-linked immunosorbent assays. HCV infection or Toll-like receptor 3/7/8 activation could induce CLEC18A expression in Huh7.5 cells. Upregulated CLEC18A interacts with Rab5 and Rab7 and enhances type I/III interferon production to inhibit HCV replication in hepatocytes. However, overexpressed CLEC18A suppressed phagocytic activity in phagocytes. Significantly decreased levels of the Fc gamma receptor (FcγR) IIA were found in the neutrophils of HCV patients, particularly in those with MC (P < 0.005). We demonstrated that CLEC18A could inhibit FcγRIIA expression in a dose-dependent manner through the production of NOX-2-dependent reactive oxygen species to impair the uptake of ICs. Additionally, CLEC18A suppresses the Rab7 expression that is induced by starvation. Overexpressed CLEC18A does not affect autophagosome formation but does reduce the recruitment of Rab7 to autophagosomes, thereby retarding the maturation of autophagosomes and affecting autophagosome-lysosome fusion. We offer a novel molecular machinery with which to understand the association of HCV infection with autoimmunity and propose that CLEC18A may act as a candidate biomarker for HCV-associated MC. IMPORTANCE During infection, the host immune system produces cellular factors to protect against pathogen invasion. However, when the immune response overreacts and there is dysregulated cytokine homeostasis, autoimmunity occurs following an infection. We identified a cellular factor that is involved in HCV-related extrahepatic manifestation, namely, CLEC18A, which is expressed abundantly in hepatocytes and phagocytes. It inhibits HCV replication in hepatocytes by interacting with Rab5/7 and enhancing type I/III IFN expression. However, overexpressed CLEC18A inhibited FcγRIIA expression in phagocytes to impair phagocytosis. Furthermore, the interaction between CLEC18A and Rab5/7 may reduce the recruitment of Rab7 to autophagosomes and thereby retard autophagosome maturation and cause immune complex accumulation. A decreasing trend in CLEC18A levels that was accompanied by reduced HCV RNA titers and diminished cryoglobulin was observed in the sera of HCV-MC patients after direct-acting antiviral therapy. CLEC18A may be used for the evaluation of anti-HCV therapeutic drug effects and could be a potential predisposing factor for the development of MC syndrome.

Article Topic: Neuropathies Due to Infections and Antimicrobial Treatments

Purpose of eview

The aim of this review is to discuss the presentation, diagnosis, and management of polyneuropathy (PN) in selected infections. Overall, most infection related PNs are an indirect consequence of immune activation rather than a direct result of peripheral nerve infection,  Schwann cell infection, or toxin production, though note this review will describe infections that cause PN through all these mechanisms. Rather than dividing them by each infectious agent separately, we have grouped the infectious neuropathies according to their presenting phenotype, to serve as a guide to clinicians. Finally, toxic neuropathies related to antimicrobials are briefly summarized.

Recent findings

While PN from many infections is decreasing, increasing evidence links infections to variants of GBS. Incidence of neuropathies secondary to use of HIV therapy has decreased over the last few years.

Summary

In this manuscript, a general overview of the more common infectious causes of PN will be discussed, dividing them across clinical phenotypes: large- and small-fiber polyneuropathy, Guillain-Barré syndrome (GBS), mononeuritis multiplex, and autonomic neuropathy. Rare but important infectious causes are also discussed.

Impact of treatment with direct-acting antivirals on inflammatory markers and autoantibodies in HIV/HCV co-infected individuals

HCV infection could have extrahepatic manifestations due to an aberrant immune response. HCV/HIV co-infection increases such persistent immune activation. Aim of the present study is to describe the evolution of inflammatory markers used in clinical practice, mixed cryoglobulinemia (MC) and autoantibody reactivity in co-infected individuals who achieved sustained virological response (SVR) after DAA treatment. This prospective, observational study included all HIV/HCV co-infected subjects who started any DAA regimen from 2015 to 2020. Samples for laboratory measurements (ferritin, C reactive protein, C3 and C4 fractions, rheumatoid factor, MC, anti-thyroglobulin Ab, anti-thyroid peroxidase Ab, ANCA, ASMA, anti-LKM, anti-DNA, AMA, ANA, T CD4+ and CD8+ cell count, and CD4/CD8 ratio) were collected at baseline, after 4 weeks, at end of treatment, and at SVR12. The analysis included 129 individuals: 51.9% with a F0-F3 fibrosis and 48.1% with liver cirrhosis. Cryocrit, C3 fraction, and rheumatoid factor significantly improved at week 4; ferritin, anti-thyroglobulin Ab, and C4 fraction at EOT; total leukocytes count at SVR12. MC positivity decreased from 72.8% to 35.8% (p < .001). T CD4+ cell slightly increased at SVR12, but with an increase also in CD8+ resulting in stable CD4/CD8 ratio. Autoantibody reactivity did not change significantly. ANA rods and rings positivity increased from 14.8% to 28.6% (p = .099): they were observed in three subjects without exposure to RBV. DAA therapy may lead to improvement in inflammatory markers and MC clearance but without significant changes in autoantibodies reactivity and CD4/CD8 ratio over a follow up of 12 weeks.

Infection-Related Cryoglobulinemic Glomerulonephritis with Serum Anti-Factor B Antibodies Identified and Staining for NAPlr/Plasmin Activity Due to Infective Endocarditis

In this rare case of infection-related cryoglobulinemic glomerulonephritis with infective endocarditis, a 78-year-old male presented with an acute onset of fever and rapidly progressive glomerulonephritis. His blood culture results were positive for Cutibacterium modestum, and transesophageal echocardiography showed vegetation. He was diagnosed with endocarditis. His serum immunoglobulin M, IgM-cryoglobulin, and proteinase-3-anti-neutrophil cytoplasmic antibody levels were elevated, and his serum complement 3 (C3) and C4 levels were decreased. Renal biopsy results showed endocapillary proliferation, mesangial cell proliferation, and no necrotizing lesions on light microscopy, with strong positive staining for IgM, C3, and C1q in the capillary wall. Electron microscopy showed deposits in the mesangial area in the form of fibrous structures without any humps. Histological examination confirmed a diagnosis of cryoglobulinemic glomerulonephritis. Further examination showed the presence of serum anti-factor B antibodies and positive staining for nephritis-associated plasmin receptor and plasmin activity in the glomeruli, suggesting infective endocarditis-induced cryoglobulinemic glomerulonephritis.

A Rare Case of Nephrotic Syndrome in the Setting of Sjogren Syndrome-related Cryoglobulinemic Vasculitis

Cryoglobulinemia is a rare entity which frequently occurs in the setting of an underlying disease, with chronic hepatitis C virus infections and primary Sjogren syndrome being the most common underlying conditions. Cryoglobulinemic vasculitis (CV) is an immune-mediated type of small-vessel vasculitis with a broad spectrum of specific organ involvement, including renal, pulmonary, peripheral nerve, and cutaneous involvement and variable manifestations that can be life threatening. Moreover, a strong relationship between cryoglobulinemia and CV, with the future development of lymphoma, is well established. We present the case of a 72-year-old Caucasian male referred for nephrotic syndrome and acute renal injury. A diagnosis of Sjogren syndrome-associated CV was made, and he was successfully treated with rituximab and plasma exchange sessions.

Annular vasculitic lesions

Vasculitic skin findings may present with annular morphologies. This group of conditions consists of capillaritis, such as pigmented purpuric dermatoses, and vasculitis, which is often classified by the affected vessel size. Annular vasculitic lesions may be the presenting sign of systemic disease, thus requiring thorough exploration to reach an accurate diagnosis and guide proper disease management. Herein we review the clinical presentation, histopathology, and treatments for cutaneous vasculitic disease that may present with annular lesions.

Monoclonal gammopathy of renal significance: Multidisciplinary approach to diagnosis and treatment

Monoclonal gammopathy of renal significance (MGRS) is a hemato-nephrological term referring to a heterogeneous group of kidney disorders characterized by direct or indirect kidney injury caused by a monoclonal immunoglobulin (MIg) produced by a B cell or plasma cell clone that does not meet current hematologic criteria for therapy. MGRS-associated kidney diseases are diverse and can result in the development of end stage kidney disease (ESKD). The diagnosis is typically made by nephrologists through a kidney biopsy. Many distinct pathologies have been identified and they are classified based on the site or composition of the deposited Mig, or according to histological and ultrastructural findings. Therapy is directed towards the identified underlying clonal population and treatment decisions should be coordinated between hematologists and nephrologists in a multidisciplinary fashion, depend on the type of MGRS, the degree of kidney function impairment and the risk of progression to ESKD.

Central and Peripheral Nervous System Complications of Vasculitis Syndromes from Pathology to Bedside: Part 2-Peripheral Nervous System

PURPOSE OF REVIEW

Peripheral nervous system vasculitides (PNSV) are a heterogeneous group of disorders with a clinical subset that may differ in prognosis and therapy. We provide a comprehensive update on the clinical assessment, diagnosis, complications, treatment, and follow-up of PNSV.

RECENT FINDINGS

Progress in neuroimaging, molecular testing, and peripheral nerve biopsy has improved clinical assessment and decision-making of PNSV, also providing novel insights on how to prevent misdiagnosis and increase diagnostic certainty. Advances in imaging techniques, allowing to clearly display the vessel walls, have also enhanced the possibility to differentiate inflammatory from non-inflammatory vascular lesions, while recent histopathology data have identified the main morphological criteria for more accurate diagnosis and differential diagnoses. Overall, the identification of peculiar morphological findings tends to improve diagnostic accuracy by defining a clearer boundary between systemic and non-systemic neuropathies. Therefore, the definition of epineurium vessel wall damage, type of vascular lesion, characterization of lymphocyte populations, antibodies, and inflammatory factors, as well as the identification of direct nerve damage or degeneration, are the common goals for pathologists and clinicians, who will both benefit for data integration and findings translation. Nevertheless, to date, treatment is still largely empiric and, in some cases, unsatisfactory, thus often precluding precise prognostic prediction. In this context, new diagnostic techniques and multidisciplinary management will be essential in the proper diagnosis and prompt management of PNSV, as highlighted in the present review. Thirty to fifty percent of all patients with vasculitis have signs of polyneuropathy. Neuropathies associated with systemic vasculitis are best managed according to the guidelines of the underlying disease because appropriate workup and initiation of treatment can reduce morbidity. Steroids, or in severe or progressive cases, cyclophosphamide pulse therapy is the standard therapy in non-systemic vasculitic neuropathies. Some patients need long-term immunosuppression. The use of novel technologies for high-throughput genotyping will permit to determine the genetic influence of related phenotypes in patients with PNSV.

Cutaneous Pedal Manifestations in Patient With Hepatitis C Virus-Associated Cryoglobulinemia: Case Report and Review of Literature

Cryoglobulinemia is an uncommon blood dyscrasia that can manifest itself in the lower extremity. Due to the insidious nature of this disease, dermatological symptoms and ulcerations can easily be mistaken for more common entities. The authors present an overview of cryoglobulinemia and a case report of a patient with lower extremity manifestations of this disorder. This can provide specific guidance on the steps necessary to accurately establish the diagnosis of cryoglobulinemia or rule it out and pursue other etiologies causing lower extremity ulceration.

Non-hepatitis-associated mixed cryoglobulinemia with polyclonal plasma cells disease and alcoholic cirrhosis: A rare case report

Mixed cryoglobulinemia refers to the serum presence of a variety of cryoglobulins, which are defined as immunoglobulins that precipitate at temperatures of < 37°C. The most common cause of mixed cryoglobulinemia is hepatitis C virus (HCV), while other infections, including hepatitis B virus (HBV) and HIV infections, and lymphoproliferative and autoimmune disorders have also been associated with the disease. We reported a rare case of type II-III mixed cryoglobulinemia caused by alcoholic cirrhosis. We need to increase the awareness of and facilitate the early identification of mixed cryoglobulinemia in our clinical study when encountering a patient with liver cirrhosis combined with renal impairment so that treatment can begin early to improve the success rate of therapy and reduce the fatality rate in a potentially life-saving therapy.

Preventive plasmapheresis for rituximab related flare in cryoglobulinemic vasculitis

Introduction

Rituximab monotherapy represents the main therapeutic option for cryoglobulinemic vasculitis (CV) with severe organ involvement. However, initial worsening of the CV, known as rituximab-associated CV flare (=CV flare), has been described and are associated with high mortality rates. The aim of the present study is to evaluate the outcomes of plasmapheresis initiated before or during rituximab treatment, as prevention of CV flare.

Methods

We conducted a retrospecttive study in our tertiary referral center from 2001 to 2020. We have included all patients with CV receiving rituximab and divided them in two groups whether they had flare prevention by plasmapheresis or not. We evaluated rituximab-related CV flare incidence in both groups. CV flare was defined as the onset of a new organ involvement or worsening of the initial manifestations within 4 weeks following rituximab.

Results

Among the 71 patients included, 44 received rituximab without plasmapheresis (control = CT cohort) and 27 received plasmapheresis before or during rituximab treatment (preventive plasmapheresis = PP cohort). PP was given to patients thought to have a high risk of CV flare, with significantly more severe diseases than patients in the CT cohort. Despite this, no CV flare was observed in the PP group. In the other hand, 5 flares occurred in the CT cohort.

Conclusion

Our results show that plasmapheresis is efficient and well tolerated to prevent rituximab-associated CV flare. We believe that our data support the use of plasmapheresis in this indication, especially in patients with high risk of CV flare.

Pathophysiology and clinical manifestations of immune complex vasculitides

Immune complex (IC) vasculitides present inflammations of vessel walls associated with perivascular deposition of immunoglobulins (Igs), mostly ICs. They encompass systemic and skin-limited variants of IgA vasculitis (IgAV), cryoglobulinemic vasculitis (CV), rheumatoid, lupus, and hypocomplementemic vasculitides, serum sickness cutaneous IgM/IgG (non-IgA) vasculitis, and recurrent macular (hypergammaglobulinemic or exertion-induced) vasculitis. Serum sickness and CV fulfill the criteria of a type III hypersensitivity immune reaction as large lattices of the IC precipitate at vessel walls and activate polymorphonuclear neutrophils (PMNs). Immunoglobulin-A vasculitis differs with regard to the causes of perivascular deposition of ICs since here many IgA1 molecules are hypoglycosylated (Gd-IgA1), which appears to facilitate their perivascular deposition in skin and mesangium (via e.g. CD71). The reasons for increased generation of immunoglobulins or formation of IC and their perivascular deposition in either skin or systemic organs are different and not fully explored. A common denominator of OC vasculitides is the activation of PMNs near the vessel wall via Fcy or Fcα receptors. Acute episodes of IgAV additionally require PMNs to become preactivated by IgA1 or by IC already in circulation. This intravascular priming results in increased adherence and subsequently vessel-destructive NETosis when they encounter IgA deposited at the vessel walls. Binding of IgA1 to PMNs in blood stream is associated with increased serum levels of hypogalactosidated IgA1. The characteristic clinical picture of IgAV (and also of so-called IgG/IgM vasculitis) comprises palpable or retiform purpura with a clear predilection for lower legs, probably due to stasis-related reduction in blood velocity, while in other IC vasculitides, additional factors influence the sites of vasculitides. Our knowledge of distinct forms and different pathophysiological pathways of IC vasculitides may lead to in efficacious or targeted therapies. Antibodies to complement components or intestinal budesonide for IgAV are promising agents (the latter suppresses the pathophysiologically related IgA nephropathy by reducing the generation of mucosal IgA.

An Unusual Case of Seronegative Cryoglobulinemic Glomerulonephritis with Dominant Organized IgA Deposits Associated with Staphylococcal Infection: Casual or Causal Relationship?

Introduction

Cryoglobulinemia refers to the presence of cryoglobulins (CGs) in the serum, encompassing a group of diseases caused by the type of circulating GC. Cryoglobulinemic glomerulonephritis (CryoGN) is the principal manifestation of renal involvement. The diagnosis may be challenging because the hallmark of cryoglobulinemia is the detection of CG in the serum. However, cases of CryoGN without serological evidence of CGs are not uncommon in clinical practice, often diagnosed by anatomopathological findings in the renal biopsy.

Case Presentation

We report the case of an 86-year-old male who developed renal impairment, nephritic syndrome, and nephrotic-range proteinuria, without serological evidence of CGs, associated with staphylococcal bacteremia without apparent focus. Renal biopsy and pathological examination showed a membranoproliferative glomerulonephritis pattern with CD61-negative pseudothrombi. Immunofluorescence microscopy showed atypical IgA-dominant deposits. Electron microscopy revealed amorphous subendothelial and mesangial deposits and organized electrodense deposits within capillary loops (pseudothrombi) with microtubular substructure measuring 20-40 nm in thickness. These findings were consistent with seronegative CryoGN and microtubular organized atypical IgA-dominant deposits.

Discussion

In this report, we discuss the clinical, analytical, and histopathological findings of a rare case of CryoGN without serological evidence of CGs. Regarding the etiology that triggered the glomerular disease in our patient, we conducted an exhaustive study in order to determine the underlying cause of CryoGN. At the time of biopsy, the patient had an active staphylococcal bacteremia. There are reports that postulate that staphylococcal antigens drive activation of immune system and in consequence, could cause this rare form of IgA-dominant glomerulonephritis with cryoglobulinemic features. After ruling out other causes of cryoglobulinemia, we discuss a plausible causal relationship of the staphylococcal infection in the pathogenesis of CryoGN in our patient.

An Unusual Presentation of Cryoglobulinemia in a Patient With Undiagnosed Sjögren's Syndrome and Treated Marginal Zone Lymphoma

Our case details a 47-year-old female who presented to our cancer hospital with a petechial rash of the lower extremities as well as a headache and blurred vision for the prior two days. She was found to have systolic pressures in the 200s in the emergency department and was admitted for a hypertensive emergency. Notable medical history includes marginal zone lymphoma (MZL) status post-submandibular resection at an outside institution in 11/2017 (thought to be in remission). With her history in mind, she also reported subjective submandibular swelling on admission and an unintentional 25-pound weight loss over the eight weeks prior to admission. A PET scan was completed, which showed diffusely increased reticuloendothelial activity, and a follow-up bone marrow biopsy was without residual lymphoma activity. Creatinine was markedly elevated with significant proteinuria, and a renal biopsy revealed thrombotic microangiopathy, acute tubular injury, and moderate interstitial fibrosis. Remarkable laboratory tests included positive quantitative cryoglobulins ("cryocrit") and low complement 4 (C4). Qualitative cryoglobulins were never obtained, unfortunately. She was started on prednisone and transferred to a nearby academic hospital for formal rheumatologic evaluation. Importantly, testing at this facility showed elevated Sjögren's syndrome-related antigen A (SSA/Ro) antibodies. Also elicited at the academic hospital was that she had been experiencing symptoms of chronic dry eyes and mouth years even before her diagnosis of MZL. She was diagnosed with primary Sjögren's syndrome, which was thought to be the cause of her likely mixed cryoglobulinemia and the precipitant of her acute renal failure with hypertensive emergency, her skin changes, her anemia, and her hypocomplementemia. Of note, prior to discharge from the academic hospital, the patient's cryoglobulin testing was negative after prolonged steroid treatment, and she was placed on rituximab for maintenance. Our case is important as it helps illustrate one of the myriad precipitants of mixed cryoglobulinemia, in this case possibly untreated Sjögren's syndrome.

Serum cystatin C is an early renal dysfunction biomarker in patients with hepatitis C virus

Background

Hepatitis C virus (HCV) may induce extrahepatic manifestations as acute or chronic renal dysfunction. The aim was to evaluate the diagnostic role of some biomarkers as cystatin C, cryoglobulins, rheumatoid factor (RF), and complement C3 for extrahepatic renal affection in newly diagnosed patients with HCV infection.

Methods

Blood and urine were collected from randomized individuals screened for new HCV infection (n=400). The studied populations were divided into 3 groups: control group I: thirty healthy individuals not suffering from either liver or kidney diseases, group IIa: thirty HCV patients who have positive HCV antibody test but showed negative PCR test, and group IIb: thirty HCV patients who showed positive results for both HCV antibody and PCR tests.

Results

In HCV group IIb, levels of serum total bilirubin, AST and ALT, and urine albumin/creatinine ratio were increased whereas serum albumin and creatinine clearance were decreased versus other groups. However, the levels of blood urea nitrogen and serum creatinine were still within the normal range in all groups. In HCV group IIb, cystatin C, cryoglobulins, and RF levels were increased; meanwhile, serum creatinine/cystatin C ratio and complement 3 levels were decreased compared to the other groups. HCV-infected patients significantly had higher serum cystatin C (>1.24 mg/L, P<0.001) and lower creatinine/cystatin C ratio (<70.1μMol/mg, P=0.002), and cystatin C was significantly correlated with liver and kidney parameters.

Conclusion

High serum cystatin C and low creatinine/cystatin C ratio may be early indicators of mild renal dysfunction with normal serum levels of creatinine in HCV-infected individuals.

Cryoglobulinemic Vasculitis Associated with Monoclonal Gammopathy of Undetermined Significance Developed after Sustained Virologic Response of Hepatitis C: A Case Report

A 72-year-old woman had a history of chronic hepatitis C virus (HCV) infection previously treated with interferon to achieve a sustained virologic response. Thereafter, she developed polyarthritis and purpura of the lower extremities as well as progressive renal dysfunction with hypertension and proteinuria that had occurred in the last three months. Laboratory investigations revealed seropositivity for cryoglobulin but negative findings for HCV RNA. She was ultimately diagnosed with cryoglobulinemic glomerulonephritis complicated by monoclonal gammopathy of undetermined significance (MGUS) based on the pathological findings of the kidney and bone marrow, indicating that MGUS-induced cryoglobulinemic vasculitis may occur even after HCV elimination.

Hepatitis B virus-associated cryoglobulinaemia diffuse endocapillary proliferative glomerulonephritis: a case report and literature review

Cryoglobulinaemia can manifest as fatigue, purpura, and joint pain, and can involve the kidneys and peripheral nervous system. Type II and mixed cryoglobulinemia cases are usually associated with hepatitis C virus infection and autoimmune diseases, and most cases reported outside China have been related to hepatitis C virus. The pathological manifestation of cryoglobulinaemia glomerulonephritis is always membranous proliferative glomerulonephritis or membranous nephropathy; other pathological types are rare. This current case report describes a female patient with hepatitis B virus (HBV)-associated cryoglobulinaemic glomerulonephritis. The patient had hepatitis B complicated with purpura, abnormal urinalysis and renal function. She was positive for rheumatoid factor and had decreased complement, and her blood cryoglobulin level was positive. The pathological findings were consistent with late-stage capillary proliferative glomerulonephritis, which improved after steroid, immunosuppressant and anti-HBV treatment.

The Role of Autoantibody Testing in Modern Personalized Medicine

Personalized medicine (PM) aims individualized approach to prevention, diagnosis, and treatment. Precision Medicine applies the paradigm of PM by defining groups of individuals with akin characteristics. Often the two terms have been used interchangeably. The quest for PM has been advancing for centuries as traditional nosology classification defines groups of clinical conditions with relatively similar prognoses and treatment options. However, any individual is characterized by a unique set of multiple characteristics and therefore the achievement of PM implies the determination of myriad demographic, epidemiological, clinical, laboratory, and imaging parameters. The accelerated identification of numerous biological variables associated with diverse health conditions contributes to the fulfillment of one of the pre-requisites for PM. The advent of multiplex analytical platforms contributes to the determination of thousands of biological parameters using minute amounts of serum or other biological matrixes. Finally, big data analysis and machine learning contribute to the processing and integration of the multiplexed data at the individual level, allowing for the personalized definition of susceptibility, diagnosis, prognosis, prevention, and treatment. Autoantibodies are traditional biomarkers for autoimmune diseases and can contribute to PM in many aspects, including identification of individuals at risk, early diagnosis, disease sub-phenotyping, definition of prognosis, and treatment, as well as monitoring disease activity. Herein we address how autoantibodies can promote PM in autoimmune diseases using the examples of systemic lupus erythematosus, antiphospholipid syndrome, rheumatoid arthritis, Sjögren syndrome, systemic sclerosis, idiopathic inflammatory myopathies, autoimmune hepatitis, primary biliary cholangitis, and autoimmune neurologic diseases.

Concomitant Nephrotic Syndrome and Cryoglobulinemia in a Case of Malignant Mesothelioma

Malignant pleural mesothelioma is rarely associated with nephrotic syndrome. Cryoglobulinemia is found in various pathological statuses, such as hepatitis C virus infection but rarely in malignant neoplasms. We recently encountered a patient with malignant mesothelioma coincident with nephrotic syndrome and cryoglobulinemia in the course of chemotherapy. A 60-year-old man employed as a building painter was diagnosed with malignant mesothelioma by lung biopsy two years earlier and was started on chemotherapy. Nivolumab seemed effective in controlling mesothelioma, but skin immune-related adverse events occurred during the course of treatment. After discontinuation of nivolumab and administration of gemcitabine as an alternative therapy, the patient was referred to a nephrologist because of the subsequent development of edema, renal injury, and proteinuria. Following the investigation, he was diagnosed with nephrotic syndrome and cryoglobulinemia with C4-dominant cold activation. However, a percutaneous renal biopsy could not be performed due to persistent severe cough induced by pleural involvement. The patient died a little over three years after the pathological diagnosis of pleural mesothelioma. Our case had three key features nephrotic syndrome was possibly associated with malignant mesothelioma; cryoglobulinemia occurred in malignant mesothelioma; and concomitant nephrotic syndrome and cryoglobulinemia occurred after chemotherapy. Unfortunately, our rare case lacks a basis in renal pathology or evidence of links between the pathogenesis of malignant mesothelioma, cryoglobulinemia, and nephrotic syndrome. This case does not provide a causal mechanism, but may be worth adding to the case list as one of the rare renal involvement in a patient with malignant mesothelioma.

Spectrum of Large and Medium Vessel Vasculitis in Adults: Primary Vasculitides, Arthritides, Connective Tissue, and Fibroinflammatory Diseases

Purpose of Review

To provide a comprehensive overview of the spectrum of large and medium vessel vasculitis in adults with primary vasculitides, arthritides, connective tissue, and fibroinflammatory diseases as well as vasculitis mimics, for an efficient differential diagnosis and initial diagnostic approach.

Recent Findings

Imaging has had a tremendous impact on the diagnosis of medium to large vessel vasculitis, now often replacing histopathologic confirmation and identifying new disease manifestations (e.g., intracranial disease in giant cell arteritis; vascular manifestations of IgG4-related disease). Novel diseases or syndromes involving blood vessels have been described (e.g., VEXAS-Syndrome with polychondritis). The use of the terms “medium” or “large” vessel varies considerably between medical specialties.

Summary

The differential diagnosis of large and medium vessel vasculitis is becoming increasingly complex as new entities or disease manifestations of known inflammatory rheumatic diseases are regularly identified. A more precise and widely recognized definition of the vessel sizes would make future research more comparable.

Mixed cryoglobulinaemic vasculitis with pulmonary infiltrates and cavitation

Cryoglobulinaemic vasculitis is an immune complex-mediated vasculitis with a myriad of clinical manifestations. We report a rare case of a patient in her 60s with rheumatoid arthritis who presented with fever of unknown origin, cutaneous leucocytoclastic vasculitis and progressive pulmonary infiltrates with cavitation. Extensive investigation for an infectious aetiology was unrevealing. Blood investigations revealed high-titre rheumatoid factor, hypocomplementaemia, raised inflammatory markers and the presence of type 2 cryoglobulins. A diagnosis of cryoglobulinaemic vasculitis with pulmonary involvement was made, and the patient was treated with high-dose prednisolone and rituximab, which resulted in complete resolution of lung changes and marked clinical improvement. This case highlights the rarity of lung involvement, including cavitation in cryoglobulinaemic vasculitis.

Recognizing the true face of noninfectious cryoglobulinemic glomerulonephritis

Cryoglobulinemia encompasses a group of diseases with circulating aberrant Igs, which can cause systemic cryoglobulinemic vasculitis, including cryoglobulinemic glomerulonephritis. The complexities of different types and changing etiologies of cryoglobulinemias determine its heterogeneous clinical manifestations and diagnostic difficulties. In this issue of Kidney International, Javaugue et al. have emphasized the diagnostic points of cryoglobulinemic glomerulonephritis and hematological disorders as the major culprits of noninfectious cryoglobulinemic glomerulonephritis in a large cohort.