Cryoglobulinemia Vasculitis

Clinical and Serological Profiles in Cryoglobulinemia: Analysis of Isotypes and Etiologies

Objectives: Cryoglobulinemia (CG) is marked by abnormal immunoglobulins (Ig) in serum, precipitating at temperatures below 37 °C. Current classification categorizes CG into three subtypes (types I, II, and III) based on Ig clonality. The features distinguishing patients with CG based on their etiology remain unidentified. Aiming to characterize clinical and serological profiles of CG individuals, we conducted an observational analysis of a large cohort of patients and compared their characteristics based on underlying causes: hepatovirus (HV) infections, rheumatic diseases (RD), hematological disorders, and unidentified etiology (essential CG). Methods: We analyzed 252 cryoglobulin-positive serum samples from 182 patients and classified these into the four etiological groups. A separate sub-analysis was carried out for 10 patients meeting criteria for multiple diseases. We collected demographic, clinical, and laboratory data: CG characterization, complement (C3 and C4) levels, antinuclear antibodies (ANA), and rheumatoid factor (RF). Kruskal-Wallis and Wilcoxon-Mann-Whitney U-tests were used for comparisons. Results: Most patients (93.3%) had mixed cryoglobulinemia (types II + III), with 6.7% having type I. HV infection, predominantly hepatitis C, was the main (52.9%) associated condition within the cohort, followed by rheumatic (27.3%) and hematological (9.8%) disorders. In our cohort, ANA were frequent (45.3%) and often associated with RF positivity (43.6%) and decreased complement levels (C3: 42.4%, C4: 32.5%). Essential CG and CG associated with RD had a higher prevalence of cutaneous manifestations (p < 0.01) and renal involvement (p = 0.017). Hematological disorder-related CG showed higher cryoglobulin and RF concentrations (p < 0.01), despite milder symptoms. Conclusions: Our study underscores a mixed prevalence of CG across disease subgroups, with hepatitis-C virus as the primary factor, followed by rheumatic and hematological disorders. Four clinical and serological profiles of CG were identified based on their etiologies.

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.

Rituximab in non-systemic vasculitic neuropathy: a single-center experience

OBJECTIVES

This case series reports clinical features and outcome of four patients with non-systemic vasculitic neuropathy (NSVN) treated with the anti-CD20 agent rituximab.

METHODS

Clinical, electrophysiological and biopsy data were retrospectively obtained and evaluated. Only patients with pathological definite or probable NSVN were included. Extensive clinical and laboratory work-up excluded systemic vasculitis. Follow-up data for at least 12 months and up to five years is provided. Outcome of the patients was assessed using the MRC-Sum Score, Prineas Score and Neurological Symptom Score.

RESULTS

Two of four patients treated with rituximab achieved disease remission and one patient remained stable under anti-CD20 therapy after a required treatment switch due to toxic side effects of cyclophosphamide. One patient deteriorated under rituximab induction. Rituximab was well tolerated in all patients.

DISCUSSION

Anti-CD20 therapy might be an alternative in NSVN patients requiring further treatment escalation or treatment switch due to side effects of corticosteroids or cyclophosphamide.

Thrombosis in vasculitis: An updated review of etiology, pathophysiology, and treatment

Introduction

Thromboembolic disease is a complication of many vasculitides. A common observation is that thromboembolic events coincide with the period of vasculitic disease, but the mechanism by which this occurs remains unclear. Inflammatory thrombosis is now recognized as a symptom of arteritis rheumatic, and vasculitides such as Behçet's syndrome (BS), and anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) or giant cell arteritis (GCA). This systematic review aimed to explain recent findings related to etiology, pathophysiology, and treatment methods for BS, AAV, and medium/large-vessel vasculitis.

Methods

A comprehensive literature search on English sources from PubMed, Scopus, MEDLINE, Science Direct, ProQuest, AIM, CINAHIL, and ELDIS databases was used to find the relevant articles and reports. The relevant papers (having full text) were obtained until June 2023. Two independent reviewers screened the titles and abstracts of the obtained articles, and a third arbitrator resolved disputes between the reviewers.

Results and conclusion

It is becoming increasingly clear that certain systemic inflammatory diseases, like vasculitis, are linked to a higher risk of both venous and arterial thrombosis. An increased incidence of thromboembolic disease in AAV has been noted, particularly during times of active disease. Growing evidence supports the use of immunosuppression in the management of venous thrombosis in vasculitis. These patients also have a higher risk of developing ischemic disease.

Mixed cryoglobulinaemia vasculitis secondary to marginal zone lymphoma in a patient with end-stage renal failure on haemodialysis

Cryoglobulinaemia vasculitis can present with a variety of symptoms and there is limited data on the incidence and presentation of cryoglobulinaemia vasculitis in haemodialysis patients. We report a case of a 63-year-old male who had a series of presentations with rash, visual changes, abdominal pain, weight loss, fevers and digital ischaemia. This is on a background of a congenital single kidney with end-stage renal failure secondary to diabetes and hypertension, receiving haemodialysis for nearly 5 years. He initially experienced a leukocytoclastic vasculitis rash confirmed on skin biopsy, followed by multiple hospital presentations for undifferentiated abdominal pain and fever of unknown source. Jejunal biopsy revealed intestinal vasculitis. His peripheral blood flow cytometry and bone marrow biopsy were consistent with marginal zone lymphoma (indolent subtype, IgM kappa clone). Further testing revealed a type II cryoglobulinaemia consisting of an IgM kappa monoclonal band with polyclonal IgG (cryocrit 5%). A diagnosis of cryoglobulinaemia vasculitis was established and he was treated with pulsed methylprednisolone and rituximab therapy. However, after receiving three doses of rituximab the patient developed a presumed vasculitis-associated pulmonary haemorrhage for which he received treatment with five sessions of plasma exchange. His symptoms resolved and cryocrit reduced to < 1% after his final dose of rituximab. The clinical features of cryoglobulinaemia may be difficult to detect in chronic haemodialysis patients and vigilance is required.

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.

Cryoglobulin-Associated Retinal Vasculitis: Retrospective Case Series

Purpose: To highlight clinical and imaging features of 5 patients diagnosed with retinal vasculitis and cryoglobulins. Methods: This retrospective case series describes clinical and angiographic features of retinal vasculitis and serum cryoglobulins and is the most extensive series to our knowledge. Results: Five female patients were diagnosed with retinal vasculitis and serum cryoglobulins. The average age at time of cryoglobulin identification was 46 years (range, 28-72 years), although retinal vasculitis had been present for various durations. Fluorescein angiograms demonstrated large-vessel and small-vessel segmental leakage in 3 patients, only large-vessel segmental leakage in 1 patient, and only small-vessel segmental leakage in 1 patient. Treatment included topical steroids, intraocular steroid injections, oral corticosteroids, oral antimetabolites, and biologic therapy. At the time of this report, 4 of 5 patients had persistent angiographic leakage; however, none had retinal vascular occlusions. Conclusions: Various treatments were efficacious, although resolution was difficult. No patient experienced retinal vascular occlusions or other types of end-organ compromise.

Longitudinal rheumatoid factor autoantibody responses after SARS-CoV-2 vaccination or infection

Background

Rheumatoid factors (RFs) are autoantibodies that target the Fc region of IgG, and are found in patients with rheumatic diseases as well as in the healthy population. Many studies suggest that an immune trigger may (transiently) elicit RF responses. However, discrepancies between different studies make it difficult to determine if and to which degree RF reactivity can be triggered by vaccination or infection.

Objective

We quantitatively explored longitudinal RF responses after SARS-CoV-2 vaccination and infection in a well-defined, large cohort using a dual ELISA method that differentiates between true RF reactivity and background IgM reactivity. In addition, we reviewed existing literature on RF responses after vaccination and infection.

Methods

151 healthy participants and 30 RA patients were included to measure IgM-RF reactivity before and after SARS-CoV-2 vaccinations by ELISA. Additionally, IgM-RF responses after a SARS-CoV-2 breakthrough infection were studied in 51 healthy participants.

Results

Published prevalence studies in subjects after infection report up to 85% IgM-RF seropositivity. However, seroconversion studies (both infection and vaccination) report much lower incidences of 2-33%, with a trend of lower percentages observed in larger studies. In the current study, SARS-CoV-2 vaccination triggered low-level IgM-RF responses in 5.5% (8/151) of cases, of which 1.5% (2/151) with a level above 10 AU/mL. Breakthrough infection was accompanied by development of an IgM-RF response in 2% (1/51) of cases.

Conclusion

Our study indicates that de novo RF induction following vaccination or infection is an uncommon event, which does not lead to RF epitope spreading.

Waldenström's Macroglobulinemia and Cryoglobulinemic Glomerulonephritis: An Unusual Case of Monoclonal Gammopathy of Renal Significance

Cryoglobulins are immunoglobulins that precipitate at temperatures below 37 °C and dissolve upon reheating. They can induce small-vessel vasculitis with renal involvement. Cryoglobulinemic glomerulonephritis is a rare manifestation that occurs in patients with monoclonal gammopathy, specifically Waldenström's macroglobulinemia. We present the case of a 52-year-old patient with a history of cutaneous vasculitis and hypothyroidism, who presented with generalized edema, moderate anemia, hypercholesterolemia, nephrotic range proteinuria of 12.69 g/day, microhematuria, arterial hypertension, and hypocomplementemia via the classical pathway, without acute kidney injury and with negative serological studies and positive cryoglobulins in the second determination. Serum and urine protein electrophoresis and immunofixation studies showed a monoclonal band of IgM and kappa light chain. Renal biopsy was consistent with cryoglobulinemic glomerulonephritis. In the context of dysproteinemia and cryoglobulinemic glomerulonephritis, bone-marrow aspiration and biopsy were performed, leading to the diagnosis of Waldenström's macroglobulinemia. Monoclonal gammopathies have been described in association with type I cryoglobulinemias. This described association is uncommon, which is why we present this case, along with a review of the literature.

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.

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.

Prognosis and long-term outcomes in type I cryoglobulinemia: A multicenter study of 168 patients

Type I cryoglobulinemia (CG) accounts for 10%-15% of all cryoglobulinemias and are exclusively seen in clonal proliferative hematologic conditions. In this multicenter nationwide cohort study, we analyzed the prognosis and long-term outcomes of 168 patients with type I CG (93 (55.4%) IgM and 75 [44.6%] IgG). Five- and 10-year event-free survivals (EFS) were 26.5% (95% CI 18.2%-38.4%) and 20.8% (95% CI 13.1%-33.1%), respectively. In multivariable analysis, factors associated with poorer EFS were renal involvement (HR: 2.42, 95% CI 1.41-4.17, p = .001) and IgG type I CG (HR: 1.96, 95% CI 1.13-3.33, p = 0.016), regardless of underlying hematological disorders. IgG type I CG patients had higher cumulative incidence of relapse (94.6% [95% CI 57.8%-99.4%] vs. 56.6% [95% CI 36.6%-72.4%], p = .0002) and death at 10 years (35.8% [19.8%-64.6%] vs. 71.3% [54.0%-94.2%], p = .01) as compared to IgM CG, respectively. Overall, complete response of type I CG at 6 months was 38.7%, with no significant difference between Igs isotypes. In conclusion, renal involvement and IgG CG were identified as independent poor prognostic factors of type I CG.

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.

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.

The Impact of Human Platelet Antigen Allele on Antiplatelet Antibodies and Cryoglobulins in Patients with Primary Immune Thrombocytopenia and Hepatitis C Virus-Associated Immune Thrombocytopenia

Background And Objectives

Human platelet antigens (HPAs) are alloantigens associated with antiplatelet alloantibodies and the risk of immune thrombocytopenia (ITP). However, few studies have investigated associations among HPAs, antiplatelet autoantibodies, and cryoglobulins.

Methods

We enrolled 43 patients with primary ITP, 47 with hepatitis C virus-associated ITP (HCV-ITP), 21 with hepatitis B virus-associated ITP (HBV-ITP), 25 controls with HCV, and 1013 normal controls. We analyzed HPA allele frequencies, including HPA1-6 and 15, antiplatelet antibodies binding to platelet glycoprotein (GP) IIb/IIIa, Ia/IIa, Ib/IX, IV, human leukocyte antigen class I, cryoglobulin IgG/A/M, and their associations with thrombocytopenia.

Results

In the ITP cohort, HPA2ab, rather than HPA2aa, predicted a low platelet count. HPA2b was associated with the risk of developing ITP. HPA15b was correlated with multiple antiplatelet antibodies. In HCV-ITP patients, HPA3b was correlated with anti-GPIIb/IIIa antibodies. HCV-ITP patients with anti-GPIIb/IIIa antibodies had a higher positive rate of cryoglobulin IgG and IgA compared with those without anti-GPIIb/IIIa antibodies. Overlapping detection was also found among other antiplatelet antibodies and cryoglobulins. Like the antiplatelet antibodies, cryoglobulins were associated with clinical thrombocytopenia, implying their close relationship. Finally, we extracted cryoglobulins to confirm the exhibition of cryoglobulin-like antiplatelet antibodies. In contrast, in primary ITP patients, HPA3b was correlated with cryoglobulin IgG/A/M rather than anti-GPIIb/IIIa antibodies.

Conclusion

HPA alleles were associated with antiplatelet autoantibodies and had different impacts in primary ITP and HCV-ITP patients. HCV-ITP was considered to be a symptom of mixed cryoglobulinemia in HCV patients. The pathophysiology may differ between these two groups.

A Rare Manifestation of Hepatitis A Associated Cryoglobulinemia

Cryoglobulins can precipitate in the blood when exposed to lower temperatures. These abnormal immunoglobulins are more commonly affiliated with Hepatitis C infection but there have been cases reported with Hepatitis A association for which we present this case. The patient was treated with steroids which did show gradual improvement of symptoms but, ultimately, the patient developed renal failure and required temporary hemodialysis. Care should be taken to assess patients with cryoglobulins for other viral serologies besides Hepatitis C.

[Peripheral neuropathies during systemic diseases: Part II (vasculitis)]

Primary systemic vasculitides, mainly of the small and medium-sized vessels, are frequently associated with peripheral neuropathies. When the disease is already known, the appearance of a neuropathy should suggest a specific injury, especially when associated with other systemic manifestations. Conversely, when neuropathy is inaugural, close collaboration between neurologists and internists is necessary to reach a diagnosis. A standardized electro-clinical investigation specifying the topography, the evolution and the mechanism of the nerve damage enables the positive diagnosis of the neuropathy. Several elements orient the etiological diagnosis and allow to eliminate the main differential diagnosis: non systemic vasculitic neuropathy. The existence of associated systemic manifestations (glomerular or vascular nephropathy, interstitial lung disease, intra-alveolar hemorrhage, ENT involvement…), biological markers (ANCA, cryoglobulinemia, rheumatoid factor), and invasive examinations allowing histological analysis (neuromuscular biopsy) are all useful tools for.

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.

Hepatitis B virus-infection related cryoglobulinemic vasculitis. Clinical manifestations and the effect of antiviral therapy: A review of the literature

Objective

Hepatitis B virus (HBV) infection causes chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Furthermore, about 20% of the patients develop extrahepatic manifestations such as cryoglobulinemic vasculitis (CV), polyarteritis nodosa, non-rheumatoid arthritis, glomerulonephritis and non-Hodgkin lymphoma. This review analyzed literature data on clinical manifestations of HBV-related CV and the impact of antiviral therapy with analoques nucleotide.

Methods

A PubMed search was performed to select eligible studies in the literature, up to July 2022.

Results

Some studies have analyzed clinical manifestations in HBV-related CV and have investigated the role of antiviral therapy with nucleotides analogues (NAs). Clinical manifestations of CV vary from mild to moderate (purpura, asthenia and arthralgias) to severe (leg ulcers, peripheral neuropathy, glomerulonephritis, and non-Hodking lymphoma). NAs therapy leads to suppression of HBV-DNA; therefore, it is capable of producing clinical response in the majority of patients with mild to moderate symptoms.

Conclusion

Antiviral therapy with NAs is the first choice for HBV suppression and control of mild to moderate disease. In severe vasculitis (glomerulonephritis, progressive peripheral neuropathy and leg ulcers), rituximab alone or with plasma-exchange is always indicated in combination with antiviral therapy.

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.

Leukocytoclastic vasculitis in association with linear epidermal basement membrane zone immunoglobulin deposition: Linear vasculitis

Cutaneous leukocytoclastic vasculitis (LCV) has a distinctive clinical and light microscopic presentation; however, the etiologic basis of LCV is varied. Most cases are attributable to immune complex deposition within a vessel wall and represent an Arthus type III immune complex reaction. The prototypic immunoreactant profile is characterized by granular deposits of components of complement activation in concert with immunoglobulin within the cutaneous vasculature. We encountered nine patients with vasculitic and/or vesiculobullous clinical presentations exhibiting an LCV in association with an immunoreactant profile characterized by homogeneous linear deposits of immunoglobulin along the dermal epidermal junction in a fashion resembling an autoimmune vesiculobullous disease. Among the clinical presentations were palpable purpura, urticarial vasculitis, and vesiculobullous eruptions with supervening purpura. Two patients with Crohn disease presented with classic palpable purpura with biopsy-proven LCV, and direct immunofluorescence (DIF) studies demonstrated linear immunoglobulin G (IgG) with floor localization on the salt-split skin assay. Four patients with systemic lupus erythematosus (SLE) showed purpuric vesiculobullous lesions, with evidence of a neutrophilic interface dermatitis and LCV in three of the four. The remaining patient had urticarial nonbullous lesions showing small-vessel vasculitiswith a neutrophilic interface dermatitis. In all of the patients with SLE, DIF studies showed linear immunoglobulin deposits within the basement membrane zone (BMZ). These constellation of findings clinically, light microscopically, and by immunofluorescence were those of a vasculitic presentation of bullous systemic lupus erythematosus. Two patients had linear IgA disease, which was drug induced in one and paraneoplastic in the other, and the dominant morphology on biopsy in both cases was an LCV. One patient microscopically demonstrated drug-associated and eosinophilic enriched LCV with DIF studies showing striking linear deposits of IgG suggestive of bullous pemphigoid, which was consistent with a vasculitic presentation of drug-induced bullous pemphigoid. In all cases, typical granular vascular immunoglobulin and complement deposition compatible with immune complex mediated vasculitis was observed. It is likely that local immune complexes derived from BMZ antigen bound to antibody are pathogenically relevant. We propose the designation of linear vasculitis for this unique scenario of LCV and linear immunoglobulin epidermal BMZ staining, which in some cases represents a vasculitic presentation of conventional autoimmune vesiculobullous disease.

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.

Extrahepatic Manifestations of Chronic HBV Infection and the Role of Antiviral Therapy

The hepatitis B virus (HBV) infection leads to chronic hepatitis, cirrhosis, and hepatocarcinoma. However, about 20% of patients experience extrahepatic manifestations such as polyarteritis nodosa, non-rheumatoid arthritis, non-Hodgkin lymphoma, cryoglobulinemic vasculitis, and glomerulonephritis. These influence the patient's morbidity, quality of life and mortality. The treatment of an HBV infection is based on nucleotide analogues (NAs) which are safe and effective for the suppression of HBV-DNA in almost 100% of cases. A few studies have shown that NAs induce a viral response and an improvement of extrahepatic diseases. There is a lack of a thorough analysis of the available treatments for extrahepatic HBV manifestations. In 90% to 100% of cases, the NAs stop the HBV replication, and they produce a clinical response in the majority of patients with mild to moderate extrahepatic signs/symptoms. Arthritis can definitely disappear after the HBV elimination and, in some cases, the HBV eradication following NAs therapy appears to improve the renal function in HBV-related nephropathies. Plasma exchange can be used in subjects who are suffering from the most aggressive forms of cryoglobulinemic vasculitis and glomerulonephritis, progressive peripheral neuropathy, and life-threatening cases, and this can be combined with glucocorticosteroids and antiviral agents. In selected refractory patients, the use of rituximab in conjunction with NAs therapy can be considered. The review provides an update on extrahepatic conditions that are linked to HBV and the impact of treating HBV with NAs.

Imaging of intestinal vasculitis focusing on MR and CT enterography: a two-way street between radiologic findings and clinical data

Diagnosis of intestinal vasculitis is often challenging due to the non-specific clinical and imaging findings. Vasculitides with gastrointestinal (GI) manifestations are rare, but their diagnosis holds immense significance as late or missed recognition can result in high mortality rates. Given the resemblance of radiologic findings with some other entities, GI vasculitis is often overlooked on small bowel studies done using computed tomography/magnetic resonance enterography (CTE/MRE). Hereon, we reviewed radiologic findings of vasculitis with gastrointestinal involvement on CTE and MRE. The variety of findings on MRE/CTE depend upon the size of the involved vessels. Signs of intestinal ischemia, e.g., mural thickening, submucosal edema, mural hyperenhancement, and restricted diffusion on diffusion-weighted imaging, are common in intestinal vasculitis. Involvement of the abdominal aorta and the major visceral arteries is presented as concentric mural thickening, transmural calcification, luminal stenosis, occlusion, aneurysmal changes, and collateral vessels. Such findings can be observed particularly in large- and medium-vessel vasculitis. The presence of extra-intestinal findings, including within the liver, kidneys, or spleen in the form of focal areas of infarction or heterogeneous enhancement due to microvascular involvement, can be another radiologic clue in diagnosis of vasculitis. The link between the clinical/laboratory findings and MRE/CTE abnormalities needs to be corresponded when it comes to the diagnosis of intestinal vasculitis.

Histological Findings in Kidney Biopsies of Patients with Monoclonal Gammopathy—Always a Surprise

Background: The simultaneous occurrence of impaired kidney function and paraproteinemia is common in our constantly aging society. Both can be independent entities; however, renal insufficiency can also be caused by the paraprotein. We assessed all kidney biopsies in patients with monoclonal gammopathy in our clinic over the past 20 years and evaluated the histological results. Methods: Biopsies were systematically performed in nearly all patients with paraproteinemia and impaired kidney function (n = 178). The histological findings were systematically evaluated and correlated with the initial clinical diagnosis. Results: We found cast nephropathy (CN) in n = 66 (37.1%) biopsies, AL amyloidosis in n = 31 (17.4%) biopsies, monoclonal immunoglobulin deposition disease (MIDD) in n = 7 (3.9%) biopsies and other renal diseases (ORDs) in n = 74 (41.6%) biopsies. In the latter group, paraprotein-associated changes were found in 37 of 74 (50%) patients, whereas paraprotein-independent changes were found in the other half. Whereas, in the group of patients with MGUS, the findings were heterogenous, most of the patients with known multiple myeloma (MM) or B-NHL showed malignancy-associated changes in the kidney. The biopsy changed the diagnoses in a significant proportion of the patients: The group of patients with MM grew from 71 to 112 patients, whereas, in the MGUS group, only 31 of 44 patients remained. Conclusion: Kidney biopsies in patients with paraproteinemia and renal impairment show a wide range of findings that can lead to a change in diagnosis.

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.

Impact of direct-acting antiviral regimens on hepatic and extrahepatic manifestations of hepatitis C virus infection

Hepatitis C virus (HCV) is a common cause of liver disease and is associated with various extrahepatic manifestations (EHMs). This mini-review outlines the currently available treatments for HCV infection and their prognostic effect on hepatic manifestations and EHMs. Direct-acting antiviral (DAA) regimens are considered pan-genotypic as they achieve a sustained virological response (SVR) > 85% after 12 wk through all the major HCV genotypes, with high percentages of SVR even in advanced fibrosis and cirrhosis. The risk factors for DAA failure include old males, cirrhosis, and the presence of resistance-associated substitutions (RAS) in the region targeted by the received DAAs. The effectiveness of DAA regimens is reduced in HCV genotype 3 with baseline RAS like A30K, Y93H, and P53del. Moreover, the European Association for the Study of the Liver recommended the identification of baseline RAS for HCV genotype 1a. The higher rate of hepatocellular carcinoma (HCC) after DAA therapy may be related to the fact that DAA regimens are offered to patients with advanced liver fibrosis and cirrhosis, where interferon was contraindicated to those patients. The change in the growth of pre-existing subclinical, undetectable HCC upon DAA treatment might be also a cause. Furthermore, after DAA therapy, the T cell-dependent immune response is much weaker upon HCV clearance, and the down-regulation of TNF-α or the elevated neutrophil to lymphocyte ratio might increase the risk of HCC. DAAs can result in reactivation of hepatitis B virus (HBV) in HCV co-infected patients. DAAs are effective in treating HCV-associated mixed cryoglobulinemia, with clinical and immunological responses, and have rapid and high effectiveness in thrombocytopenia. DAAs improve insulin resistance in 90% of patients, increase glomerular filtration rate, and decrease proteinuria, hematuria and articular manifestations. HCV clearance by DAAs allows a significant improvement in atherosclerosis and metabolic and immunological conditions, with a reduction of major cardiovascular events. They also improve physical function, fatigue, cognitive impairment, and quality of life. Early therapeutic approach with DAAs is recommended as it cure many of the EHMs that are still in a reversible stage and can prevent others that can develop due to delayed treatment.

Neuromuscular Complications of SARS-CoV-2 and Other Viral Infections

In this article we review complications to the peripheral nervous system that occur as a consequence of viral infections, with a special focus on complications of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We discuss neuromuscular complications in three broad categories; the direct consequences of viral infection, autoimmune neuromuscular disorders provoked by viral infections, and chronic neurodegenerative conditions which have been associated with viral infections. We also include discussion of neuromuscular disorders that are treated by immunomodulatory therapies, and how this affects patient susceptibility in the current context of the coronavirus disease 2019 (COVID-19) pandemic. COVID-19 is associated with direct consequences to the peripheral nervous system via presumed direct viral injury (dysgeusia/anosmia, myalgias/rhabdomyolysis, and potentially mononeuritis multiplex) and autoimmunity (Guillain Barré syndrome and variants). It has important implications for people receiving immunomodulatory therapies who may be at greater risk of severe outcomes from COVID-19. Thus far, chronic post-COVID syndromes (a.k.a: long COVID) also include possible involvement of the neuromuscular system. Whether we may observe neuromuscular degenerative conditions in the longer term will be an important question to monitor in future studies.

Clinical impact and prognosis of cryoglobulinemia and cryofibrinogenemia in systemic sclerosis

INTRODUCTION

An association of systemic sclerosis (SSc) with cryoglobulin and/or cryofibrinogenemia has been described. However, clinical, biological, morphological and prognostic implications are unknown. The objective of this study was to describe the phenotype and evaluate the prognosis of cryoglobulinemia and/or cryofibrinogenemia in the progression of SSc.

MATERIALS AND METHODS

Patients were included from the Systemic Scleroderma Toulouse Cohort (SSTC), between June 1, 2005 and May 31, 2018, and underwent a measurement of a cryoglobulin and/or cryofibrinogen in immunology laboratory at the Toulouse University Hospital Center. Patients with and without cryoglobulinemia >50 mg/l and patients with and without cryofibrinogenemia were compared to identified the impact of cryoprcipitate on the phenotype. Mortality based on cryoprecipitate was explored.

RESULTS

166 patients were included in the study. 43.3% and 46.6% had a cryoglobulinemia >50 mg/l and cryofibrinogenemia, respectively. Cryoglobulin >50 mg was not associated with microvascular damage. Cryoglobulin does not influence the phenotype. 5-and 10-years survival were 97.6% and 88.8% respectively in patients with cryoglobulinemia >50 mg/l versus 91.9% and 78.4% in patients without cryoglobulin>50 mg/l. 10-years survival was better for patients with cryoglobulinemia >50 mg/l (log-rank 0.0363). Cryofibrinogenemia was not associated with neoplasia, any clinical (in particular ischemic damage), biological or morphological features. Cryofibrinogenemia had no influence on the mortality of these patients.

CONCLUSION

Cryoglobulinemia and cryofibrinogenemia are frequent in SSc. The presence of cryoprecipitate (cryoglobulin or cryofibrinogen) not influence the phenotype and has not associated with a poor survival.

The characteristics of seronegative and seropositive non-hepatitis-associated cryoglobulinemic glomerulonephritis

cryoglobulinemic glomerulonephritis (CryoGN) are not well-defined and cases with undetectable serum cryoglobulin (seronegative CryoGN) have not been investigated. Corresponding author: To resolve this, we retrospectively identified 81 patients with biopsy-proven non-hepatitis CryoGN, including 22 with seronegative CryoGN. The median age was 61 years and 76% presented with nephritic syndrome. A hematologic condition was found in 89% of patients, including monoclonal gammopathy of renal significance (65%) and symptomatic lymphoproliferative disorder (35%). In the seropositive group, 56% had type II, 29% type I, 8% type III cryoglobulin. Extrarenal manifestations, mostly of skin, were present in 64% and were significantly less common in seronegative CryoGN. Glomerular deposits by immunofluorescence were IgM dominant (84%) and polytypic (70%) in the seropositive group, whereas 52% of seronegative cases had monotypic deposits (i.e., type I cryoglobulin). Ultrastructurally, the deposits were organized in 77% of cases. Substructure appearance significantly differed according to the type of CryoGN, forming most commonly short cylindrical structures in type II and other organized substructures in type I CryoGN. Most patients were treated with clone-directed therapy. On follow up (median 33 months), 77% had partial or complete remission, 10% reached kidney failure and 14% died. Predictors of kidney failure on univariate analysis were AKIN stage 3, positive rheumatoid factor and biclonal gammopathy at diagnosis. We conclude that most CryoGN cases (types I and II) are due to hematologic condition and are associated with favorable outcome after clone-directed therapy. Seronegative CryoGN accounts for about a quarter of cases and is mostly a kidney-limited disease. Thus, further investigations are needed to unravel the pathophysiology of seronegative CryoGN.

Transient elastography score is elevated during rheumatoid factor-positive chronic hepatitis C virus infection and rheumatoid factor decline is highly variable over the course of direct-acting antiviral therapy

BACKGROUND

Elevated rheumatoid factor (RF) levels and systemic immune activation are highly prevalent during chronic hepatitis C virus (HCV) infection. Direct-acting antiviral (DAA) therapy has been associated with normalization of various soluble immune activation parameters. Whether the RF levels relate to soluble immune activation markers during chronic HCV infection, and over what time frame RF levels normalize during and after DAA treatment is unknown and was investigated here.

METHODS

In a longitudinal study, plasma and serum was obtained from HCV infected RF positive (RF+) and RF negative (RF-) participants. The levels of RF, HCV RNA and soluble markers of inflammation were determined before (week 0), during (weeks 4, 8 and 12) and after (week 24) treatment with HCV DAA therapy. In a subset of RF+ participants, the analysis was extended to over 70 weeks after therapy initiation. Hepatic and other clinical parameters were determined at baseline (week 0) in all participants.

RESULTS

Before therapy, transient elastography (TE) score was greater in RF+ compared to RF- HCV infected participants, while the systemic levels of soluble inflammatory markers were comparable. Following DAA therapy initiation, HCV RNA levels became undetectable within 4 weeks in both the RF+ and RF- groups. RF levels declined in the first 6 months in most RF+ persons but most commonly remained positive. The levels of some soluble inflammatory markers declined, mainly within 4 weeks of DAA therapy start, in both the RF+ and RF- groups. The baseline (week 0) TE score correlated with RF levels before, during and after DAA therapy, while plasma IL-18 levels correlated with RF level after DAA therapy.

CONCLUSION

During chronic HCV infection, TE score is elevated in RF+ HCV infected individuals and factors other than HCV viremia (including liver stiffness or fibrosis and select markers of inflammation) likely contribute to persistence of RF after treatment of HCV with DAA.

Non HCV-Related Mixed Cryoglobulinemic Vasculitis With Biopsy-Proven Renal Involvement: The Effects of Rituximab

In the countries where HCV infection is still endemic, about 90% of subjects with mixed cryoglobulinemia had previously been infected with HCV and about 80% are RNA positive. Remarkable results in severe HCV-related cryoglobulinemic vasculitis have been obtained with Rituximab. Details of the clinical characteristics and effective treatment of non HCV-related cryogloulinemic syndromes are presently lacking. This paper reports on a prospective single-Center open study aimed at evaluating the clinical presentation and effects of Rituximab administered alone in patients with severe non HCV-related cryoglobulinemic syndrome. The study group included 11 patients followed for at least 6 months. Three patients had type I cryoglobulinemia, 6 had type II and the remaining 2 patients had type III. Mean cryocrit was 2.5%. Four out of 11 patients had symptomatic sicca complex with anti-SSA (Ro)/anti SSB (La) antibodies. All 11 patients presented with biopsy-proven renal involvement, 4 out of 11 with leukocytoclastic vasculitis, and 8 with involvement of the peripheral nervous system. Renal biopsy revealed diffuse membranoproliferative glomerulonephritis (MPGN) in 9 out of 11 patients. Extracapillary proliferation and necrosis of the glomerular tuft was observed in 1 of these 9 cases. Interstitial nephritis together with mesangial expansion and capillary immune deposits were observed in 1 patient. Prevalent interstitial fibrosis and glomerular sclerosis were detected in the remaining case. Patients underwent treatment with rituximab alone. After 6 months we observed a remarkable improvement in the necrotizing skin ulcers and a substantial amelioration of the electrophysiological parameters of motor and sensory peripheral neuropathy. Improvement in both renal function (from 2.8 to 1.4 mg/dl, p < 0.001) and proteinuria (from 4.2 g/24 to 0.4 g/24 h, p < 0.001) was found in 10 out of 11 patients, while 1 could not be fully treated because of a severe infusion reaction and sudden development of anti-Rituximab antibodies. Good renal response was confirmed at the end of follow-up (38.4 months). Three patients had a relapse at 6, 12, and 48 months, respectively. In our cohort the administration of 4 once-weekly infusions of Rituximab followed by 2 more infusions after 1 and 2 months proved to be effective in the management of these rare patients.

Painful ulcerations: the sole clinical sign of mixed cryoglobulinaemia secondary to marginal zone lymphoma

A man in his 70s with background vascular disease presented with 7 months of painful non-resolving lower leg ulcers with eschar and petechiae, left lower ear lobe ulceration and dusky inflammation of the right ear. He demonstrated good bilateral pedal pulses and no peripheral oedema. No lymphadenopathy was palpated.Biopsy suggested leucocytoclastic vasculitis on chronic stasis changes. Blood investigations showed elevated rheumatoid factor and mixed polyclonal IgG and monoclonal IgM cryoglobulins. He was diagnosed with mixed cryoglobulinaemia, and consequent conducted flow cytometry revealed CD5 +marginal zone lymphoma with elevated serum free light chains and kappa/lambda ratio.One-month following rituximab and chlorambucil therapy, the patient's pain had much improved, ear ulcers had healed and several leg ulcers had reduced in width and depth. The petechial eruption had also resolved.

[Cryoglobulinemic vasculitis]

Cryoglobulinemic vasculitis (CV) is a rare immune complex disease of small vessels (capillaries, venules or arterioles) with detection of cryoglobulins (CG). These are serum proteins that precipitate at temperatures below the normal body temperature. The laboratory diagnostics are logistically challenging because the temperature of the blood sample must be maintained continuously at 37 °C until arrival in the laboratory to prevent early precipitation of the proteins with adsorption to corpuscular blood components. Cryoglobulins can be divided into three classes (types I-III), with each class associated with specific underlying diseases and symptom complexes. Cryoglobulinemia can be caused by hematological, virological or autoimmune diseases and mixed forms also occur. The most common cause to date is a hepatitis C infection. Treatment of the underlying disease is obligatory, with antiviral treatment of hepatitis C offering the rare possibility of causal treatment. Depending on the severity of cryoglobulinemia, immunosuppressive therapy is indicated to prevent permanent damage caused by the inflammation.

Therapy of Chronic Viral Hepatitis: The Light at the End of the Tunnel?

Chronic viral hepatitis determines significant morbidity and mortality globally and is caused by three main etiological actors (Hepatitis B Virus, Hepatitis C Virus, and Hepatitis D Virus) with different replicative cycles and biological behaviors. Thus, therapies change according to the different characteristics of the viruses. In chronic hepatitis B, long term suppressive treatments with nucleoside/nucleotide analogues have had a dramatic impact on the evolution of liver disease and liver-related complications. However, a conclusive clearance of the virus is difficult to obtain; new strategies that are able to eradicate the infection are currently objects of research. The therapy for Hepatitis D Virus infection is challenging due to the unique virology of the virus, which uses the synthetic machinery of the infected hepatocyte for its own replication and cannot be targeted by conventional antivirals that are active against virus-coded proteins. Recently introduced antivirals, such as bulevertide and lonafarnib, display definite but only partial efficacy in reducing serum HDV-RNA. However, in combination with pegylated interferon, they provide a synergistic therapeutic effect and appear to represent the current best therapy for HDV-positive patients. With the advent of Direct Acting Antiviral Agents (DAAs), a dramatic breakthrough has occurred in the therapeutic scenario of chronic hepatitis C. Cure of HCV infection is achieved in more than 95% of treated patients, irrespective of their baseline liver fibrosis status. Potentially, the goal of global HCV elimination by 2030 as endorsed by the World Health Organization can be obtained if more global subsidised supplies of DAAs are provided.

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.

Cryoglobulinemic vasculitis in two patients with infective endocarditis: a case series

Cryoglobulins are circulating immune complexes that precipitate at cool temperatures and can induce a small-vessel vasculitis. While patients with endocarditis are well known to have circulating cryoglobulins, cryoglobulinemic vasculitis is a rare complication of infective endocarditis with infrequent publication of reported cases. We present two cases of methicillin-resistant Staphylococcus aureus tricuspid valve infective endocarditis in patients with substance use disorder complicated by cryoglobulinemic cutaneous vasculitis confirmed by skin biopsy, including one patient who developed renal and colonic manifestations of vasculitis. Both patients had symptomatic improvement in their vasculitis with appropriate antimicrobial therapy, including one patient who received a short course of prednisone and another with chronic active hepatitis C that remained untreated. Providers should have a high-index of suspicion for infective endocarditis in patients presenting with new onset cryoglobulinemic vasculitis, particularly if the patients have underlying risk factors for endocarditis.

Successful treatment with rituximab for central nervous system vasculitis caused by Epstein-Barr virus-associated lymphoproliferative disorder with immunoglobulin M gammopathy

Monoclonal gammopathy of undetermined significance (MGUS) is associated with several autoimmune conditions, including central nervous system (CNS) vasculitis. Epstein-Barr virus (EBV) is a pathogen capable of triggering a systemic immune response and is involved in the occurrence of a wide range of B-cell lymphoproliferative disorders. In systemic autoimmune diseases, EBV infection is suspected to play a central role in pathogenesis. Here, we present a case that was thought to be a systemic autoimmune disease and CNS vasculitis that developed after EBV infection, demonstrating that rituximab is effective for the treatment.

Pfizer-biontech COVID-19 RNA vaccination induces phosphatidylserine autoantibodies, cryoglobulinemia, and digital necrosis in a patient with pre-existing autoimmunity

We describe a 64-year-old Caucasian female with a history of Raynaud's disease, hand arthritis, photosensitivity, Sjogren's syndrome and leukocytoclastic vasculitis who presented with progressively worsening fingertip necrosis that began three days after receiving a first dose of Pfizer-BioNTech COVID-19 RNA vaccine. Our workup revealed cryoglobulinemia, hypocomplementemia, elevated antinuclear antibodies (ANA) and IgM antiphospholipid autoantibodies (aPL) directed against phosphatidylserine (aPL-PS), suggesting a diagnosis of systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS). The patient failed to develop anti-spike IgG antibodies up to two months following vaccination. Disease progression was halted by plasmapheresis, anticoagulation, and immune suppression. We conclude that the vaccine RNA moiety may induce SLE manifesting in APS, cryoglobulinemia, hypocomplementemia, and digital necrosis.

Neurolymphomatosis related to direct epineural invasion of the superficial peroneal nerve from subcutaneous B-cell lymphoma

Neurolymphomatosis is a rare complication of systemic lymphomas, and is classically related to hematogenous spread or intraneural spread of tumor cells from the leptomeninges. Here we report a case of neurolymphomatosis related to direct epineural invasion of the superficial peroneal nerve from subcutaneous localization of B-cell lymphoma. Nerve biopsy revealed striking histological features suggestive of contiguous infiltration of the superficial peroneal nerve by subcutaneous lymphoma. We think this case report sheds new light on neurolymphomatosis pathophysiology with an unreported mechanism in B-cell lymphoma. It also points out that the clinical spectrum in neurolymphomatosis is really variable, pure sensory mononeuritis being a rare presentation. Finally, our case is also strongly illustrative of the contribution of early nerve ultrasonography in the patient diagnosis and in guidance of the nerve biopsy.

Hepatitis C virus-related vasculitis

Cryoglobulinemic vasculitis (CryoVas) is a small-to-medium vessel systemic vasculitis caused by the deposition of mixed cryoglobulins and immune complexes. Clinical spectrum of CryoVas ranges from mild symptoms to vasculitis involving multiple organs that may progress to more life-threatening ilness. Hepatitis C virus (HCV) chronic infection is the most frequent condition to be assessed in patients with CryoVas. The mortality rate among patients with HCV-associated CryoVas is 3× that of the general population, with a 63% 10-year survival rate. The recent advent of interferon-free direct-acting antivirals (DAAs), which have the potential to induce sustained virological response rates greater than 95%, has dramatically changed the management of chronic HCV infection and HCV-related CryoVas. B-cell depleting strategies, mainly with rituximab, are the main therapeutic option in severe and refractory cases of HCV-associated CryoVas. Despite the progress in the last years on the management of chronic HCV infection, there are still unmet needs regarding therapeutic management of severe and refractory HCV-associated CryoVas.

Recurrence of Cryoglobulinemia Secondary to Hepatitis C in a Patient with HCV RNA (-) Negative in the Serum

Hepatitis C virus infection is associated with many extrahepatic manifestations such as mixed cryoglobulinemia (MC). Renal manifestation of HCV infection might present as cryo-positive membranoproliferative glomerulonephritis (MPGN). First-line therapy includes antiviral treatment as the underlying infection leads to formation of immune complexes. After introducing direct-acting antiviral agents (DAAs) cure rates of HCV infection increased. Sustained virologic response (SVR) is defined as the absence of HCV RNA in serum by a sensitive test performed 12 or 24 weeks after the end of antiviral treatment. Although HCV RNA is undetectable in the serum, it may be present in hepatocytes and peripheral blood mononuclear cells (occult HCV infection). However, the impact of DAA treatment on occult HCV infection is not clear. We report a case of recurrence of MC with MPGN and development of lymphoproliferative disorder 2 years after achieving SVR.