New insights in cryoglobulinemic vasculitis

Cryoglobulinemic vasculitis triggered by Staphylococcus aureus endocarditis with chronic hepatitis C virus co-infection: a case report and literature review

Infective endocarditis is a rare but life-threatening condition, occasionally linked to diverse immunologic manifestations, including mixed cryoglobulinemia. This can lead to cryoglobulinemic vasculitis, which has the potential for widespread organ damage. Although some cases have highlighted the relationship between infective endocarditis and cryoglobulinemic vasculitis, no comprehensive epidemiological evaluation or optimal treatment strategies have been advanced for such a combination. We present a case of methicillin-sensitive Staphylococcus aureus infective endocarditis associated with cryoglobulinemic vasculitis and conduct a literature review to compare management and outcomes in similar cases. Our patient presented with classical Meltzer's triad and mild renal involvement. Cryoimmunofixation confirmed type III cryoglobulinemia, and serum cytokines showed elevated IL-6 levels. The differential diagnosis included infective endocarditis and chronic active hepatitis C virus infection. Rapid symptom resolution after antibiotic treatment identified infective endocarditis as the likely cause of cryoglobulinemic vasculitis. Our case and review of the literature highlight that early identification of the cause of cryoglobulinemic vasculitis is crucial for selecting appropriate treatment and preventing recurrence or morbidity.

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.

Proteinase‑3‑antineutrophil cytoplasmic antibody‑associated vasculitis secondary to subacute infective endocarditis: A case report

A 58-year-old male patient was admitted to Peking University First Hospital (Beijing, China) due to recurrent hematuria, proteinuria and kidney dysfunction. The patient was positive for proteinase-3 (PR3)-antineutrophil cytoplasmic antibody (ANCA). Pathology of the kidney showed focal proliferative necrotizing glomerulonephritis with crescent formation and immune complex-mediated glomerulonephritis. The patient was diagnosed with PR3-ANCA-associated vasculitis (AAV), received intensive immunosuppressive therapy and experienced two relapses within 1 year. After admission, aortic valve vegetation was observed via echocardiography. The patient subsequently received antibiotic treatment and valve replacement, and achieved complete remission of kidney and cardiac function. The present case emphasized the importance of identifying secondary reasons for ANCA formation, especially infective endocarditis in patients with PR3-AAV.

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.

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.

Neuralgic Amyotrophy and Hourglass Nerve Constriction/Nerve Torsion: Two Sides of the Same Coin? A Clinical Review

Neuralgic amyotrophy, also called Parsonage-Turner syndrome, in its classic presentation is a brachial plexopathy or a multifocal neuropathy, involving mainly motor nerves of the upper limb with a monophasic course. Recently, a new radiological entity was described, the hourglass constriction, which is characterized by a very focal constriction of a nerve, or part of it, usually associated with nerve thickening proximally and distally to the constriction. Another condition, which is similar from a radiological point of view to hourglass constriction, is nerve torsion. The pathophysiology of neuralgic amyotrophy, hourglass constriction and nerve torsion is still poorly understood, and a generic role of inflammation is proposed for all these conditions. It is now widely accepted that nerve imaging is necessary in identifying hourglass constrictions/nerve torsion pre-surgically in patients with an acute mononeuropathy/plexopathy. Ultrasound and MRI are useful tools for diagnosis, and they are consistent with intraoperative findings. The prognosis is generally favorable after surgery, with a high rate of good motor recovery.

[Comparative analysis of the development mechanisms of cryoglobulinemic vasculitis and Sjögren's syndrome]

Cryoglobulinemic vasculitis is a disease characterized by damage of small vessels and in some cases can be a manifestation of mixed cryoglobulinemia. Mixed cryoglobulinemia is a condition in which immunoglobulins in the blood serum form precipitates at temperatures below 37 °C and dissolve again when it rises. Currently, hepatitis C (HCV) is considered the most common etiological factor of mixed cryoglobulinemia. In addition, mixed cryoglobulinemia may be associated with other infectious agents, as well as autoimmune and lymphoproliferative diseases. In the absence of such association, we can talk about essential mixed cryoglobulinemia. To understand how different nosologies in their clinical and morphological picture lead to the development of mixed cryoglobulinemia, it is necessary to carefully analyze the mechanisms of the development of some of them, namely, HCV-associated cryoglobulinemic vasculitis and Sjögren's syndrome. It is noteworthy that mixed cryoglobulinemia in relation to Sjögren's syndrome can be perceived both as its consequence and as a manifestation of the underlying disease. Such an ambiguous nature of mixed cryoglobulinemia makes it currently impossible to select clear diagnostic criteria. For this reason, it is necessary to carry out a comparison between different immunopathogenesis of mixed cryoglobulinemia in order to identify the features that form its classical manifestations.

Hepatitis C Virus-associated Cryoglobulinemic Livedo Reticularis Improved with Direct-acting Antivirals

We herein report a case of hepatitis C virus (HCV)-associated cryoglobulinemic livedo reticularis in a woman in her 60s that improved with direct-acting antivirals (DAAs). Hyperpigmentation was observed in both lower legs, and a skin biopsy confirmed livedo reticularis, suggesting a relationship with cryoglobulinemia and HCV infection. DAAs with an NS5A inhibitor+NS3/4A protease inhibitor (glecaprevir/pibrentasvir) were administered for eight weeks, and a sustained virological response (SVR) was obtained. The disappearance of serum cryoglobulin was confirmed approximately two years after an SVR was obtained and livedo reticularis was improved. DAA therapy can be an effective therapeutic option for extrahepatic complications associated with HCV infection.

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.

A Review of the Systemic Manifestations of Hepatitis B Virus Infection, Hepatitis D Virus, Hepatocellular Carcinoma, and Emerging Therapies

Chronic hepatitis B virus (HBV) infection affects about 262 million people worldwide, leading to over 820,000 deaths each year primarily due to cirrhosis and hepatocellular carcinoma. The World Health Organization has pledged to eliminate HBV as a health threat by 2030, but currently, no countries are on track to achieve this goal. One of the barriers to HBV elimination is stigma, causing shame, denial, self-isolation, self-rejection, and depression leading to those with chronic HBV less likely to get tested or seek treatment and more likely to conceal their infection. Other barriers include limited access to care and complicated and restrictive clinical practice guidelines. Increasing public and political efforts are necessary to raise awareness, increase access to care, and change screening and treatment guidelines. The current guidance of the American Association for the Study of Liver Diseases (AASLD) recommends testing only if patients are considered at risk, but this has proven to be ineffective. We propose a simplified "test all and treat all" approach with a 5-line guideline for HBV infection. Universal screening and treatment of adults is cost-effective and can prevent transmission by effectively managing chronic HBV. All patients who are hepatitis B surface antigen (HBsAg) positive with detectable HBV-DNA should receive treatment until HBsAg is undetectable for 12 months, as HBV-DNA transmission via blood transfusion can occur even at low viral loads of 16 copies/mL, and mother-to-child transmission is still a risk even with passive-active immunoprophylaxis. Furthermore, clinical outcomes after HBsAg clearance are significantly better than the clinical outcomes of those who remain HBsAg positive.

Cutaneous leukocytoclastic vasculitis associated with verapamil and atorvastatin: A case report

We report a case of biopsy-proven cutaneous leukocytoclastic vasculitis developing 10 days after starting verapamil and atorvastatin in a patient with long-standing Sjogren's syndrome. This highlights the need to monitor for this rare adverse effect.

Coexistence of cryoglobulinemia and ANCA-associated vasculitis in a chronic brucellosis patient -a case report and literature review

BACKGROUND

The renal involvement of brucellosis is not common. Here we reported a rare case of chronic brucellosis accompanied by nephritic syndrome, acute kidney injury, the coexistence of cryoglobulinemia and antineutrophil cytoplasmic autoantibodies (ANCA) associated vasculitis (AAV) superimposed on iliac aortic stent implantation. The diagnosis and treatment of the case are instructive.

CASE PRESENTATION

A 49-year-old man with hypertension and iliac aortic stent implantation was admitted for unexplained renal failure with signs of nephritic syndrome, congestive heart failure, moderate anemia and livedoid change in the left sole with pain. His past history included chronic brucellosis and he just underwent the recurrence and completed the 6 weeks of antibiotics treatment. He demonstrated positive cytoplasmic/proteinase 3 ANCA, mixed type cryoglobulinemia and decreased C3. The kidney biopsy revealed endocapillary proliferative glomerulonephritis with a small amount of crescent formation. Immunofluorescence staining revealed only C3-positive staining. In accordance with clinical and laboratory findings, post-infective acute glomerulonephritis superimposed with AAV was diagnosed. The patient was treated with corticosteroids and antibiotics and sustained alleviation of renal function and brucellosis was achieved during the course of a 3-month follow-up.

CONCLUSIONS

Here we describe the diagnostic and treatment challenge in a patient with chronic brucellosis related glomerulonephritis accompanied by the coexistence of AAV and cryoglobulinemia. Renal biopsy confirmed the diagnosis of postinfectious acute glomerulonephritis overlapping with ANCA related crescentic glomerulonephritis, which was not ever reported in the literature. The patient showed a good response to steroid treatment which indicated the immunity-induced kidney injury. Meanwhile, it is essential to recognize and actively treat the coexisting brucellosis even when there are no clinical signs of the active stage of infection. This is the critical point for a salutary patient outcome for brucellosis associated renal complications.

Serum protein electrophoresis and rheumatoid factor analysis is an effective screening strategy for cryoglobulinaemia

Accurate serum cryoglobulin detection is important to allow prompt treatment but laboratory testing requires stringent pre-analytical conditions and has long turnaround times. Serum protein electrophoresis (EPG) for paraproteinaemia and rheumatoid factor (RF) analysis may offer an effective initial screening strategy for the presence of cryoglobulinaemia. We retrospectively assessed the sensitivity of ancillary EPG and RF testing for the presence of serum cryoglobulinaemia in 586 eligible cryoglobulin positive samples received at the Royal Prince Alfred and Liverpool Hospital immunopathology laboratories over an 11-year period. Ninety-one percent of all cryoglobulin positive samples had either a detectable paraprotein or RF activity, with greatest sensitivity for type I and type II cryoglobulins (97% and 98%, respectively). The sensitivity remained high irrespective of whether EPG and RF analysis was performed with the same, or different, pre-analytical collection conditions to the cryoglobulin collection (92% vs 90%, p=0.46). Only two patients with detected cryoglobulins and no associated paraprotein or RF activity had clinical features of cryoglobulinaemia and neither required treatment. This study demonstrates that serum EPG and RF analysis has high sensitivity for the detection of clinically relevant cryoglobulinaemia, even when not collected under ideal pre-analytical conditions, and potentially offers a prompt and effective screening strategy.

Expert perspectives on pathological findings in vasculitis

Pathological findings are important in the diagnosis of vasculitis. However, due to the rarity of the disease, standard textbooks usually devote only a few pages to this topic, and this makes it difficult for clinicians not specializing in vasculitis to fully understand the pathological findings in vasculitis. To address the paucity of information, we present representative pathological findings in vasculitis classified in the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (CHCC2012). The CHCC2012 classifies 26 vasculitides into seven categories: (1) large-vessel vasculitis, (2) medium-vessel vasculitis, (3) small-vessel vasculitis, including antineutrophil cytoplasmic antibody-associated vasculitis and immune complex small-vessel vasculitis, (4) variable-vessel vasculitis, (5) single-organ vasculitis, (6) vasculitis associated with systemic disease, and (7) vasculitis associated with probable aetiology. Moreover, representative pathological findings of vasculitis-related diseases and non-inflammatory vasculopathy not mentioned in the CHCC2012 are also presented. This will be useful for clinicians to refer to typical pathological findings of vasculitis in daily practice.

Physicians' perceptions about antineutrophil cytoplasmic antibody-associated vasculitis: an online survey report in the time of the COVID-19 pandemic

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are characterized by necrotizing inflammation of small and medium-size vessels that often manifest with devastating multi-organ effects. They present with a myriad of systemic features and require potent immunosuppression. Since they are uncommonly encountered in clinical practice, it is necessary to understand physicians' knowledge and perceptions about this group of diseases. An online questionnaire was designed featuring 28 questions based on relevant global practice guidelines, recommendations, and previous online surveys on AAV. The questionnaire was validated by a core group of specialists with an interest in AAV. It was shared via social networking sites and entries were restricted to physicians. Only completed entries were analyzed with descriptive statistics. A total of 113 respondents from 21 different countries responded of whom the commonest were rheumatologists, internists, and general practitioners. Forty-five (40%) ran clinics dedicated to AAV patients as a part of their practice. They commented on organs involved in AAV; vasculitis secondary to infections, drugs or other rheumatic diseases; various tests useful for AAV diagnosis; and drug choices for induction and maintenance. They mentioned their experience regarding COVID-19 in AAV patients as well as vasculitic manifestations of COVID-19. Various methods to mitigate cardiovascular risks in AAV were mentioned. Finally, the respondents indicated how medical education needed to be strengthened to increase awareness and knowledge regarding AAV. This survey helped to inform about various perceptions regarding AAV across countries, including current practices and recent evolution of management. It also provided information on treatment of the COVID-19 in AAV patients. This survey showed that there is still a lack in understanding the prevalent definitions and there is gap between guidelines and current practice. Key Points • Perception about ANCA-associated vasculitis differ across countries. • The number of cases encountered across 21 different countries are limited implying a need for multi-national cooperation to study this disease further. • The COVID-19 pandemic has changed the approach towards ANCA-associated vasculitis by the various clinicians.

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.

Review of an Anti-CD20 Monoclonal Antibody for the Treatment of Autoimmune Diseases of the Skin

Biologic therapies targeting B-cells are emerging as an effective strategy to treat a variety of immune-mediated diseases. One of the most studied B-cell-targeted therapies is rituximab, an anti-CD20 monoclonal antibody that exemplifies B-cell depletion therapy and has served as the prototype for other anti-CD20 monoclonal antibodies and the development of biosimilars. While there are multiple studies on the use of rituximab in dermatology, a comprehensive review of rituximab therapy in autoimmune skin conditions is lacking. In this literature review, we summarize indications, treatment efficacy, and safety of rituximab among common autoimmune diseases of the skin: pemphigus vulgaris, cutaneous lupus erythematous, dermatomyositis, systemic sclerosis, thyroid dermopathy, autoimmune pemphigoid diseases, and cutaneous vasculitis diseases. Existing data on rituximab support the approach of rituximab, biosimilars, and newer B-cell-targeting therapies in immune-mediated cutaneous diseases. Overall, rituximab, which targets CD20, provides an effective alternative or concomitant option to traditional immunosuppressants in the management of various autoimmune diseases of the skin. Further studies are necessary to expand the understanding and possible utility of B-cell-targeted therapies among autoimmune skin diseases.

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.

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.

Infective Endocarditis-Associated Pauci-Immune Glomerulonephritis in a Patient With Cryoglobulinemia

Small-vessel vasculitis has a broad differential with similar clinical presentation and laboratory abnormalities, including petechial rashes, neurologic symptoms, glomerulonephritis, and abnormal inflammatory markers. Biopsy-based diagnosis is critical as the treatment varies by etiology. We report a case of a 41-year-old man with diagnosed cryoglobulinemia and hepatitis C presenting with a petechial rash, altered mental status, and acute kidney injury and ultimately found to have proteinase 3 (PR3)-antineutrophil cytoplasmic antibody (ANCA)-positive vasculitis secondary to infective endocarditis. Skin biopsy was consistent with resolving, but nonspecific vasculitis and MRI showed foci of hemosiderin deposition concerning vasculitic lesions. Blood cultures grew Enterococcus faecalis, and he was treated with IV antibiotics. Kidney biopsy showed pauci-immune necrotizing focal segmental glomerulonephritis (GN) and diffuse acute tubular necrosis (ATN). After blood cultures cleared, he was initially treated with mycophenolate for worsening renal function. When the patient stopped antibiotics unexpectedly, his kidney function worsened and improved only after immunosuppression was stopped and antibiotics were restarted. This case highlights the importance of renal biopsy in patients with multiple potential etiologies of GN. The case resolution also reinforces that patients with infective endocarditis causing ANCA-associated GN should be treated with antibiotics in addition to, and possibly instead of, immunosuppression.

Clinicopathological Spectrum of Cryoglobulinemic Glomerulonephritis without Evidence of Autoimmunity Disorders: A Retrospective Study from a Single Institute of China

BACKGROUND

Cryoglobulinemic glomerulonephritis (Cryo-GN), caused by circulating cryoglobulins, has varied etiology and clinical-pathologic manifestations. This study aimed to investigate the clinicopathological spectrum and outcome of patients with various Cryo-GN in China.

METHODS

A retrospective review of 74 Chinese patients with biopsy-proven cryoglobulin-related renal lesions in Peking University First Hospital from 2010 to 2020 was performed.

RESULTS

The mean age at diagnosis was 52.9 ± 15.0 years, and the female-to-male ratio was about 2/5. For the etiology screening, serum/urine monoclonal immunoglobulin could be detected on immunofixation electrophoresis in 34% of patients, including 6 patients who had hematological malignancies. Fifty-seven percent of patients had HBV infection, far more than HCV infection (5%). Ten percent of patients had other infections, and 27% of patients were classified as essential or idiopathic. Eleven out of the 15 patients with type II cryoglobulinemia had a consistent monotype of serum monoclonal immunoglobulins and monoclonal cryoprecipitate. The clinical manifestations were similar between various types of cryoglobulinemia. Hematuria, proteinuria, hypertension, anemia, and chronic renal insufficiency were the most common features. Fifty-three percent of patients presented with nephrotic syndrome, and 32% experienced acute kidney injury. Hypocomplementemia, serum-positive rheumatoid factor activity, and skin lesions were reported in 45%, 29%, and 28% of patients, respectively. After a median of 24 months follow-up, 18 patients reached end-stage kidney disease. The clone-targeted treatment could retard the renal deterioration compared with immunosuppressive therapy.

CONCLUSIONS

This was the largest single-center, clinicopathological retrospective study of Cryo-GN in China. Our data strongly support the association between monoclonal gammopathy and type II Cryo-GN. The renal responsive rate of immunosuppressant therapy is still suboptimal. The clone-targeted treatment shows promising effects in patients with type I or II Cryo-GN.

Necrotic lesions of the hands

An 82-year-old man with a history of end-stage renal disease due to glomerulonephritis requiring haemodialysis, hepatitis C-related liver cirrhosis and hypertensive cardiomyopathy presented with painful and necrotic lesions of both his hands. He had no other symptoms. [...]

Renal autoimmunity: The role of bacterial and viral infections, an extensive review

Autoimmunity is a process by which the loss of self-tolerance results in an immune attack against the body own tissues and organs. For autoimmunity to occur, various elements serving as triggers were described by which infections are considered one of the leading factors. In turn, renal involvement in autoimmune diseases, whether by an organ-specific attack, or as part of a systemic disease process, is well known. As bacterial and viral infections are considered to be common triggers for autoimmunity in general, we aimed to study their association with renal autoimmunity in particular. We performed an extensive search of the recent and relevant medical literature regarding renal autoimmunity syndromes such as infection-associated glomerulonephritis and vasculitis, associated with bacterial and viral infections. By utilizing PubMed and Google Scholar search engines, over 200 articles and case reports were reviewed. Among other mechanisms, direct infection of the renal parenchyma, molecular mimicry, induction of B-cells or secretion of superantigens, bacterial and viral pathogens were found to correlate with the development of renal autoimmunity. Nevertheless, this was not true for all pathogens, as some mimic autoimmune diseases and others show a surprisingly protective effect. The exact immunopathogenesis is yet to be determined, however. For conclusion, bacterial and viral infections are linked to renal autoimmunity by both direct damage and as mediators of systemic diseases. Further research particularly on the immunopathogenetic mechanisms of renal autoimmunity associated with infections is required.

Hepatitis B Virus Infection and Extra-Hepatic Manifestations: A Systemic Disease

People living with hepatitis B virus (HBV) chronic infection are exposed to high rates of liver complications including end-stage liver disease and hepatocellular carcinoma. Extrahepatic manifestations of HBV infection have long been underestimated. Several of these extrahepatic syndromes have been well described, including systemic vasculitides, glomerulonephritis, and cutaneous manifestations. Other manifestations have been more recently described such as hematological malignancies and neurological diseases. These extrahepatic manifestations are associated with significant morbidity and mortality. Although not completely understood, underlying mechanisms include HBV-induced local and systemic inflammation. Suppression of HBV replication usually improves extrahepatic manifestations. This review will discuss how HBV induces inflammation and the extrahepatic manifestations of HBV infection to guide clinical management.

Hepatitis C Virus-Related Central and Peripheral Nervous System Disorders

Hepatitis C Virus (HCV), despite being a hepatotropic virus, is the causative agent of many systemic disorders, such as vasculitis, autoimmune diseases, lymphoproliferative disorders, and a broad spectrum of neurological and psychiatric manifestations. Although symptoms have been misdiagnosed or underdiagnosed, only recently, evidence of direct (inflammatory) or indirect (immune-mediated) HCV-dependent cerebral effects has been established. HCV infection can promote acute inflammatory response, pro-coagulative status and ischemic disorders, and neurodegeneration. These effects rely on cerebral HCV replication, possibly mediated by blood-brain barrier alterations. Further study is needed to better understand the HCV-related mechanisms of brain damage.

Update on treatment strategies for vasculitis affecting the central nervous system

Vasculitis affecting the nervous system is a rare disease that can not only present with nonspecific initial symptoms, but also run a severe course without accurate treatment. Although improvements have been achieved, diagnosis of vasculitis remains challenging, because many classification criteria are unspecific or inconclusive with regard to central nervous system (CNS) manifestations. Currently, beside an isolated primary CNS vasculitis, several systemic types of vasculitis are known to affect the nervous system. In this review, we provide an overview of the pathophysiology, current therapeutic guidelines, and highlight novel treatment strategies for CNS vasculitis.

Rituximab-Associated Flare of Cryoglobulinemic Vasculitis

Background

Patients with cryoglobulinemic vasculitis (CV) can develop disease flare after rituximab administration. The objective of our study was to describe the prevalence, clinical characteristics, predisposing factors, and outcomes of patients with rituximab-associated flare of CV.

Methods

We conducted a retrospective study in a tertiary referral center until March 25, 2020.

Results

Among 64 patients with CV who received rituximab therapy in our center, 14 (22%) developed disease flare. Median age was 67.5 years. Seven patients (50%) had type II CV and the other half had either type I (n = 6) or type III (n = 1). Twelve patients (86%) had an underlying B-cell lymphoproliferative disorder as the cause of their CV. CV flare occurred after a median time of 5.5 days (range: 2–8 days). The organ systems most involved were the skin (n = 10), kidneys (n = 5), and peripheral nerves (n = 3). Five patients (36%) developed acute kidney injury (AKI), 3 of whom presented with nephritic syndrome secondary to biopsy-proven membranoproliferative glomerulonephritis. Treatment was directed against the underlying disease in addition to supportive care. Patients who developed flare were more likely to have B-cell lymphoproliferative disorder as the underlying etiology of their CV (P = 0.03). Eight patients (57%) died after a median time of 27 months.

Conclusions

Rituximab-associated flare can occur in all types of CV, tends to arise approximately 2 days and less than 1 week after rituximab administration, and is more likely to happen in patients with an underlying B-cell lymphoproliferative disorder. It does not indicate treatment failure, and rituximab should not be abandoned altogether. AKI is a common manifestation, and mortality rate at 2 years is high.

Immune mechanisms, the role of complement, and related therapies in autoimmune neuropathies

INTRODUCTION

Autoimmune neuropathies have diverse presentations and underlying immune mechanisms. Demonstration of efficacy of therapeutic agents that inhibit the complement cascade would confirm the role of complement activation.

AREAS COVERED

A review of the pathophysiology of the autoimmune neuropathies, to identify those that are likely to be complement mediated.

EXPERT OPINION

Complement mediated mechanisms are implicated in the acute and chronic neuropathies associated with IgG or IgM antibodies that target the Myelin Associated Glycoprotein (MAG) or gangliosides in the peripheral nerves. Antibody and complement mechanisms are also suspected in the Guillain-Barré syndrome and chronic inflammatory demyelinating neuropathy, given the therapeutic response to plasmapheresis or intravenous immunoglobulins, even in the absence of an identifiable target antigen. Complement is unlikely to play a role in paraneoplastic sensory neuropathy associated with antibodies to HU/ANNA-1 given its intracellular localization. In chronic demyelinating neuropathy with anti-nodal/paranodal CNTN1, NFS-155, and CASPR1 antibodies, myotonia with anti-VGKC LGI1 or CASPR2 antibodies, or autoimmune autonomic neuropathy with anti-gAChR antibodies, the response to complement inhibitory agents would depend on the extent to which the antibodies exert their effects through complement dependent or independent mechanisms. Complement is also likely to play a role in Sjogren's, vasculitic, and cryoglobulinemic neuropathies.

A Case of Overlap Syndrome of Systemic Sclerosis and Cryoglobulinemic Vasculitis With Central Nervous System Involvement

Mixed cryoglobulinemic vasculitis (CV) is occasionally caused by autoimmune diseases including systemic sclerosis. Multiorgan involvement such as skin, kidney, and peripheral nerve involvement is common in mixed CV. However, central nervous system (CNS) involvement is extremely rare. Here, we report a case of overlap syndrome of limited cutaneous systemic sclerosis and mixed cryoglobulinemic vasculitis with CNS involvement. The neurologic deficits and systemic symptoms improved promptly after steroid and cyclophosphamide therapy.

Cryoglobulins: Identification, classification, and novel biomarkers of mysterious proteins

Cryoglobulins consist of serum immunoglobulins that precipitate below 37°C and resolubilize upon warming. The clinical triad of cryoglobulinemia usually includes purpura, weakness, and arthralgia. Cryoglobulinemic syndrome, clinically defined as a systemic vasculitis, is associated with chronic infection with hepatitis C virus (HCV) and autoimmune disorders and can evolve into B-cell malignancies. While the current literature about HCV-associated cryoglobulinemia is not very limited, little is known about the immunologic and serologic profiles of affected patients. Therefore, comprehension of the pathogenetic mechanisms underlying cryoprecipitation could be very helpful. Due to the persistence of viral antigenic stimulation, biomarkers to use after the worsening progression of HCV infection to lymphoproliferative and/or autoimmune diseases are widely needed. Laboratory methods used to detect and characterize low concentrations of cryoprecipitates and immunotyping patterns could improve patient management. The most critical factor affecting cryoglobulin testing is that the pre-analytical phase is not fully completed at 37°C.

Cold Agglutinins and Cryoglobulins Associate With Clinical and Laboratory Parameters of Cold Urticaria

Mast cell-activating signals in cold urticaria are not yet well defined and are likely to be heterogeneous. Cold agglutinins and cryoglobulins have been described as factors possibly associated with cold urticaria, but their relevance has not been explained. We performed a single-center prospective cohort study of 35 cold urticaria patients. Cold agglutinin and cryoglobulin test results, demographics, detailed history data, cold stimulation test results, complete blood count values, C-reactive protein, total immunoglobulin E levels, and basal serum tryptase levels were analyzed. Forty six percent (n = 16) of 35 tested patients had a positive cold agglutinin test and 27% (n = 9) of 33 tested patients had a positive cryoglobulin test. Cold agglutinin positive patients, when compared to cold agglutinin negative ones, were mainly female (P = 0.030). No gender-association was found for cryoglobulins. A positive cold agglutinin test, but not a positive cryoglobulin test, was associated with a higher rate of reactions triggered by cold ambient air (P = 0.009) or immersion in cold water (P = 0.041), and aggravated by increased summer humidity (P = 0.007). Additionally, patients with a positive cold agglutinin test had a higher frequency of angioedema triggered by ingestion of cold foods or drinks (P = 0.043), and lower disease control based on Urticaria Control Test (P = 0.023). Cold agglutinin levels correlated with erythrocyte counts (r = −0.372, P = 0.028) and monocyte counts (r = −0.425, P = 0.011). Cryoglobulin concentrations correlated with basal serum tryptase levels (r = 0.733, P = 0.025) and cold urticaria duration (r = 0.683, P = 0.042). Results of our study suggest that cold agglutinins and cryoglobulins, in a subpopulation of cold urticaria patients, are linked to the course and possibly the pathogenesis of their disease.

Extremity Gangrene Caused by HBV-Related Cryoglobulinemia Vasculitis in a Patient with Diabetes - A Case Report

We presented a case of hepatitis B virus (HBV)-related type III cryoglobulinemia vasculitis (CryoVas) characterized by extremity gangrene in a patient with diabetes. The 60-year-old female had a 10-year history of poorly controlled type 2 diabetes mellitus. She complained of sudden onset pain and swelling of toes which quickly progressed to gangrene, with fingers becoming pain and dark violet. The patient was initially misdiagnosed as diabetic foot (DF). Although DF is one of the common chronic complications of diabetes, it rarely involves the hand. What is more, the ischemic manifestations of the extremity were not consistent with the results of the vascular examination and immune system changes. The patient had Raynaud's phenomenon, arthralgia, and extremity gangrene. Test results showed cryoglobulinemia multiple positive, polyclonal immunoglobulin with rheumatoid factor negative, lower complement 3, leukocytoclastic vasculitis, and HBV infection. HBV-related type III CryoVas was finally diagnosed, and a conservative therapy strategy was given. Six months after treatment with cyclophosphamide, corticosteroid, nucleoside/nucleotide analog therapy, local debridement, and dressing change, she recovered and kept no recurrence by following up for 30 months. To our knowledge, this is the first report of extremity gangrene caused by HBV-related CryoVas in a diabetic patient.

Cold urticaria - What we know and what we do not know

Cold urticaria (ColdU) is a common form of chronic inducible urticaria characterized by the development of wheals, angioedema or both in response to cold exposure. Recent research and guideline updates have advanced our understanding and management of ColdU. Today, its pathophysiology is thought to involve the cold-induced formation of autoallergens and IgE to these autoallergens, which provoke a release of proinflammatory mediators from skin mast cells. The classification of ColdU includes typical and atypical subtypes. We know that cold-induced wheals usually develop on rewarming and resolve within an hour and that anaphylaxis can occur. The diagnosis relies on the patient's history and cold stimulation testing. Additional diagnostic work-up, including a search for underlying infections, should only be done if indicated by the patient's history. The management of ColdU includes cold avoidance, the regular use of nonsedating antihistamines and the off-label use of omalizumab. However, many questions regarding ColdU remain unanswered. Here, we review what is known about ColdU, and we present important unanswered questions on the epidemiology, underlying pathomechanisms, clinical heterogeneity and treatment outcomes. Our aim is to guide future efforts that will close these knowledge gaps and advance the management of ColdU.

Acute Peripheral and/or Cutaneous Ischemic Syndrome: What Rheumatologists Should Know

ABSTRACT

In daily practice, the frequent appearance of limb and/or skin necrosis, which we term "acute peripheral and/or cutaneous ischemic syndrome" (APCIS), can be a manifestation of numerous underlying diseases, or it can sometimes be a clinical phenomenon whose etiology is undefined even after a wide investigation. The mechanisms for the development of APCIS include vessel wall abnormalities (atherosclerosis, vasculitis, and calciphylaxis), embolic processes (infectious endocarditis, atrial myxoma, and cholesterol emboli), local thrombotic injuries (genetic or acquired thrombophilias and heparin- and warfarin-induced ischemia), dysproteinemias (cryoglobulinemia and cryofibrinogenemia), or venous limb gangrene. Here, we report 5 illustrative cases of APCIS with different pathogenetic mechanisms, thereby highlighting some clinical conditions that cause APCIS that may be of special interest for rheumatologists, such as antiphospholipid syndrome, primary and secondary vasculitis, and cryoproteinemias. Furthermore, we describe a large spectrum of other causes of APCIS beyond the scope of rheumatology. Because there are no validated guidelines for APCIS, we tentatively propose an initial diagnostic workup and a therapeutic approach based on full-dose anticoagulation and immunosuppressive therapy.

Renal Involvement and HBV Infection Are Common in Chinese Patients With Cryoglobulinemia

Objectives: This study aimed to describe the main characteristics of Chinese patients with cryoglobulinemia, especially the characteristics of patients with different causes of cryoglobulinemia.

Methods: Eighty inpatients diagnosed with cryoglobulinemia from different wards in Peking Union Medical College Hospital were included in this study. Demographic, clinical, biological, and renal pathological data were collected. We analyzed the characteristics of 61 patients with different causes of cryoglobulinemia.

Results: Most patients (36/80, 45%) were diagnosed between 40 and 60 years of age. The male: female ratio was 1:1.5. Mixed (II + III) cryoglobulinemia accounted for the majority (43.8%) of cases. Renal involvement (87.5%), cutaneous involvement (57.5%), and fever (27.5%) were the most common clinical manifestations, while other manifestations included serositis and pulmonary and gastrointestinal involvement. The most common renal histopathological pattern was membranoproliferative glomerulonephritis (25/42, 59.5%). The secondary causes of cryoglobulinemia included infectious diseases (26/61, 32.5%), such as hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, and connective tissue diseases (22/61, 27.5%), such as lupus and hematologic tumors (13/61, 16.3%). Patients with hematologic tumors were diagnosed at an older age (P = 0.044) and mostly had type I cryoglobulinemia (P < 0.001). No significant difference in clinical or biological manifestations was found among patients with different causes of cryoglobulinemia.

Conclusions: This is the largest cohort of Chinese patients with cryoglobulinemia. We found that renal involvement and HBV infection might be more common in Chinese patients with cryoglobulinemia.

Human hepatitis viruses-associated cutaneous and systemic vasculitis

Human hepatitis viruses (HHVs) include hepatitis A virus, hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis delta virus, and hepatitis E virus and can cause liver inflammation in their common human host. Usually, HHV is rapidly cleared by the immune system, following acute HHV invasion. The morbidities associated with hepatitis A virus and hepatitis E virus infection occur shortly after their intrusion, in the acute stage. Nevertheless, the viral infectious process can persist for a long period of time, especially in HBV and HCV infection, leading to chronic hepatitis and further progressing to hepatic cirrhosis and liver cancer. HHV infection brings about complications in other organs, and both acute and chronic hepatitis have been associated with clinical presentations outside the liver. Vascular involvement with cutaneous and systemic vasculitis is a well-known extrahepatic presentation; moreover, there is growing evidence for a possible causal relationship between viral pathogens and vasculitis. Except for hepatitis delta virus, other HHVs have participated in the etiopathogenesis of cutaneous and systemic vasculitis via different mechanisms, including direct viral invasion of vascular endothelial cells, immune complex-mediated vessel wall damage, and autoimmune responses with stimulation of autoreactive B-cells and impaired regulatory T-cells. Cryoglobulinemic vasculitis and polyarteritis nodosa are recognized for their association with chronic HHV infection. Although therapeutic guidelines for HHV-associated vasculitis have not yet been established, antiviral therapy should be initiated in HBV and HCV-related systemic vasculitis in addition to the use of corticosteroids. Plasma exchange and/or combined cyclophosphamide and corticosteroid therapy can be considered in patients with severe life-threatening vasculitis manifestations.

Safety and effectiveness of biosimilar of Rituximab CT-P10 in the treatment of cryoglobulinemic vasculitis: the MARBLe study (Mixed cryoglobulinemiA Rituximab BiosimiLar)

Rituximab (RTX) represents a milestone in the treatment of mixed cryoglobulinemic vasculitis (MCV). Despite usually well-tolerated, RTX may induce different types of adverse drug reactions, including exacerbation of vasculitis. Recently, RTX biosimilar CT-P10 has been approved in Europe for the treatment of rheumatoid arthritis, but no data are available about effectiveness and safety of CT-P10 in the treatment of MCV. In this multicenter open-label study, we analyzed the safety of CT-P10 in patients with MCV treated in first-line or after a shift by RTX originator. Fifty-one consecutive MCV patients (females/males 35/16, median age 68 years, median disease duration 42 months, 51% HCV positive) were included in the study between July and December 2018 and were treated with CT-P10 (group 1). Safety and effectiveness of CT-P10 were compared with a retrospective group (group 2) including 75 consecutive patients treated with RTX originator between July 2017 and July 2018. Thirty-six patients were treated with CT-P10 for the first time, while the other 15 switched from RTX originator. RTX was administrated with high or dosage schemes (375 mg/m² four times a week apart/1000 mg twice one week apart or 250 mg/m² twice one week apart). During a month period after the last infusion, 13/51 adverse events (AE) were observed in group 1 and 17/75 in group 2 (p not significant). Among them, 7/13 and 6/17 (in group 1 and 2, respectively) could be considered immune-mediated AE (p not significant). At univariate analysis patients with IM-AE were more frequently males (p = 0.04) and with a lower disease duration (p = 0.03), but both the parameters were not significant at logistic regression. About clinical response after 6 months by the end of the treatment, no differences were observed between patients treated with originator and CT-P10 regarding the response to the therapy. No differences were observed in safety and effectiveness between patients naïve at RTX or switching from originator. Despite the higher prevalence of immune-mediated AE among patients treated with CT-P10 than originator, we have observed no significant differences between the 2 groups. The use of a low-dosage regimen is more common in group 1 than in group 2, representing a possible bias of the study, possibly influencing the appearance of AE. Considering the cost/efficacy ratio of biosimilars, their use could be helpful to treat a large number of MCV patients with an effectiveness and safety comparable to originator. Multicenter studies including a large number of patients and the new RTX biosimilars could be useful to fully elucidate the possible risk of immune-mediated adverse events with biosimilar drugs. Considering the cost/efficacy ratio of CT-P10, its use could help to treat a large number of MCV patients with an effectiveness and safety comparable to originator.

Rheumatologic manifestations of Hepatitis C Virus

INTRODUCTION

Hepatitis C Virus (HCV) is a well-known worldwide infection, responsible for hepatic and extrahepatic complications. Among extrahepatic manifestation, the rheumatologic are the most common ones. With the arrival of Direct Antiviral Agents (DAA), the treatment and the clinical perspective have rapidly changed, permitting to achieve a sustained virological response (SVR) and preventing complications of chronic infection.

EVIDENCE ACQUISITION

We performed on PubMed a literature search for the articles published by using the search terms "HCV infection," "HCV syndrome," "HCV-related rheumatologic disorders," "cryoglobulinemia," "cryoglobulinemic vasculitis" and "mixed cryoglobulinemia."

EVIDENCE SYNTHESIS

Mixed cryoglobulinemia (MC) is the prototype of HCV-associated rheumatologic disorder. HCV-related MC is typically considered by physicians as a human model disease to linking infection with autoimmune diseases. Chronic HCV infection can lead to a multistep process from a simple serological alteration (presence of circulating serum cryoglobulins) to frank systemic vasculitis (cryoglobulinemic vasculitis [CV]) and ultimately to overt malignant B lymphoproliferation (such as non-Hodgkin lymphoma [NHL]). Antiviral therapy is indicated to eradicate the HCV infection and to prevent the complications of chronic infection. Immunosuppressive therapy is reserved in case of organ threatening manifestations of CV. In this review, we discuss the main clinical presentation, diagnostic approach and treatment of rheumatologic manifestations of HCV infection.

CONCLUSIONS

Chronic HCV infection is responsible for complex clinical condition, ranging from hepatic to extra-hepatic disorders. Cryoglobulins are the result of this prolonged immune system stimulation, caused by tropism of HCV for B-lymphocyte.

[Neurological complications of hepatitis C infections]

Die chronische Hepatitis-C-Virus(HCV)-Infektion ist eine hochprävalente Systemerkrankung, die verschiedene neurologische Komplikationen verursachen kann. Es lassen sich HCV-assoziierte Symptome im zentralen und peripheren Nervensystem sowie der Muskulatur unterscheiden. Wichtige Pathomechanismen sind die HCV-assoziierte Autoimmunität (z. B. gemischte Kryoglobulinämie mit Polyneuropathie) und direkte Neurotoxizität (z. B. bei HCV-assoziierten kognitiven Defiziten). Die häufigsten neurologischen Komplikationen sind distal-symmetrische Polyneuropathien, Small-fiber-Neuropathien und kognitive Defizite. Die HCV-Infektion stellt außerdem einen Risikofaktor für ischämische und hämorrhagische Schlaganfälle sowie den Morbus Parkinson dar. Die frühe Identifikation und antivirale Behandlung HCV-positiver Patienten steht im Zentrum der Behandlung. Durch neue antivirale Therapien können >90 % der Patienten dauerhaft von der HCV-Infektion geheilt werden.

Cutaneous Manifestations of Chronic Liver Disease

Given the visibility of cutaneous findings, skin manifestations are often a presenting symptom of underlying systemic disease, including chronic liver disease. Many cutaneous signs and symptoms that correlate with chronic liver disease are common physical examination findings in patients with no history of liver disease. It is nonetheless important to be aware that these cutaneous findings may be an indication of underlying liver disease and often occur in the setting of such hepatic dysfunction. This article covers general cutaneous signs that may correlate with various liver diseases and describes specific cutaneous signs as they relate to more specific liver diseases.

Pathophysiology and therapy of systemic vasculitides

Systemic vasculitides represent uncommon conditions characterized by the inflammation of blood vessels that can lead to different complex disorders limited to one organ or potentially involving multiple organs and systems. Systemic vasculitides are classified according to the diameter of the vessel that they mainly affect (small, medium, large, or variable). The pathogenetic mechanisms of systemic vasculitides are still partly unknown, as well as their genetic basis. For most of the primary systemic vasculitides, a single gold standard test is not available, and diagnosis is often made after having ruled out other mimicking conditions. Current research has focused on new management protocol and therapeutic strategies aimed at improving long-term patient outcomes and avoiding progression to multiorgan failure with irreversible damage. In this narrative review, authors describe different forms of systemic vasculitides through a review of the literature, with the aim of highlighting the current knowledge and recent findings on etiopathogenesis, diagnosis and therapy.