Cryoglobulinemia: study of etiologic factors and clinical and immunologic features in 443 patients from a single center

Recurrent localized fever caused by cryoglobulinemic vasculitis following hemodialysis: A case report

Post-dialysis fever is commonly reported in patients undergoing hemodialysis (HD). However, it is often challenging to identify the underlying cause owing to the wide variety of potential factors that can lead to fever. In this case, a 66-year-old Japanese man experienced recurrent fever after HD treatment. Initially, antibiotics were prescribed to treat pneumonia, but it was later discovered that the pneumonia was an alveolar hemorrhage caused by cryoglobulinemic vasculitis. It is believed that cryoglobulin was sensitized by cold exposure owing to the dialysate temperature, which resulted in fever being experienced only after HD. Although treatment for vasculitis required prednisolone and rituximab, simple plasma exchange and a dialysate temperature of 37.5 °C dramatically suppressed the occurrence of post-dialysis fever. Cryoglobulinemia should be considered as a potential cause of fever, as it may be a common occurrence in patients undergoing HD and could be overlooked as a possible cause of localized fever following HD treatment.

Surface antigen serocleared hepatitis B virus infection increases the risk of mixed cryoglobulinemia vasculitis in male patients with chronic hepatitis C

Mixed cryoglobulinemia vasculitis (MCV) is caused in ~90% of cases by chronic hepatitis C virus (HCVposMCV) and more rarely by hepatitis B virus (HBV) infection, or apparently noninfectious. HCVposMCV develops in only ~5% of patients with chronic hepatitis C (CHC), but risk factors other than female gender have not been identified so far. We conducted a retrospective case control study investigating whether past active HBV infection, defined by hepatitis B surface antigen (HBsAg) seroclearance and anti-core antibody (HBcAb) positivity, could be a risk factor for developing HCVposMCV. The prevalence of HBsAg seroclearance was 48% within 123 HCVposMCV patients and 29% within 257 CHC patients (p=0.0003). Multiple logistic regression including as variables gender, birth year, age at HBV testing, cirrhosis, and hepatocellular carcinoma, confirmed an association of HBsAg seroclearance with HCVposMCV [adjusted odds ratio (OR) 2.82, 95% confidence interval (95% CI) 1.73-4.59, p<0.0001]. Stratification by gender, however, showed that HBsAg seroclearance was associated with HCVposMCV in male [OR 4.63, 95% CI 2.27-9.48, p<0.0001] and not in female patients [OR 1.85, 95% 95% CI 0.94-3.66, p=0.076]. HBsAg seroclearance, and more likely occult HBV infection, is an independent risk factor for HCVposMCV in male CHC patients.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

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

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

Ocular manifestations of cryoglobulinemia: a reappraisal

BACKGROUND/OBJECTIVES

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

SUBJECTS/METHODS

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

RESULTS

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

CONCLUSIONS

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

Autoimmune Hepatitis in a Patient With Cryoglobulinemic Vasculitis: A Rare Association

When a patient with cryoglobulinemic vasculitis develops a concurrent liver disease, it is typically associated with hepatitis C. Here, we report the case of a patient with cryoglobulinemic vasculitis and autoimmune hepatitis. A 54-year-old previously healthy woman presented with chronic urticaria. A skin biopsy revealed leukocytoclastic vasculitis and elevated serum cryoglobulins, leading to a diagnosis of cryoglobulinemic vasculitis. She also had abnormal liver functions, high IgG levels, positive antinuclear antibodies, and anti-smooth muscle antibodies. Liver biopsy revealed interface hepatitis confirming the diagnosis of autoimmune hepatitis. This case represents the rare occurrence of autoimmune hepatitis in a patient with cryoglobulinemic vasculitis.

Management of Hepatitis C Virus and Hepatitis B Virus Infection in the Setting of Kidney Disease

Treatment of chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) infection poses unique challenges in patients with kidney disease. Direct-acting antivirals have been a major breakthrough in eradicating HCV infection, and several pangenotypic regimens are available for patients with chronic kidney disease or end-stage kidney disease requiring dialysis with high cure rates and no need for dose adjustment. Direct-acting antiviral therapy alone can treat HCV-associated cryoglobulinemic glomerulonephritis; concurrent antiviral and immunosuppressive therapy is needed for cases of severe, organ-threatening manifestations of cryoglobulinemia. Immunosuppression may be needed for HBV-associated kidney disease (polyarteritis nodosa or membranous nephropathy) when there is evidence of severe immune-mediated injury while weighing the risk of potential viral activation. Most HBV antiviral agents need to be dose-adjusted in patients with chronic kidney disease or end-stage kidney disease requiring dialysis, and drug-drug interactions need to be carefully evaluated in patients with kidney transplants. Considerations for accepting HCV- and HBV-infected donors for kidney transplantation are discussed.

The wide spectrum of cryoglobulinemic vasculitis and an overview of therapeutic advancements

Immunoglobulins that reversibly precipitate at temperatures below 37 °C are called cryoglobulins (CGs). Cryoglobulinemia often manifests as cryoglobulinemic vasculitis (CV), whose symptoms range in severity from purpuric eruptions to life-threatening features. The majority of CV patients are infected with hepatitis C virus (HCV), whereas lymphoproliferative disorders or connective tissue diseases (CTD) are commonly diagnosed among patients with CV of non-infectious origin. In the absence of detectable associated disease, cryoglobulinemia is classified as "essential" (EMC). All HCV-positive CV patients should be given direct-acting antiviral agents (DAAs) that are consistently able to induce a sustained virologic response (SVR). Glucocorticoids (GCs) can mitigate CV-associated vasculitis, but they have no role as maintenance therapy. Cyclophosphamide restrains the hyperactive phase(s) of the disease and the post-apheresis rebound of newly synthesized CGs. Its use has been largely replaced by rituximab (RTX) in patients unresponsive to DAAs, patients progressing to B-cell non-Hodgkin lymphoma (B-NHL) and patients in whom CV persists or reappears after clearance of HCV. Therapeutic apheresis is an emergency treatment for CV patients with hyperviscosity syndrome. HCV-positive CV patients are at an increased risk of developing NHL, but the achievement of SVR can effectively prevent HCV-related NHL or induce the remission of an already established lymphoma, even without chemotherapy. The treatment of patients with IgM or IgG monoclonal cryoglobulins and an underlying immunoproliferative disorder is based on the regimens adopted for patients with the same B-cell malignancies but without circulating CGs. For patients with CTD, GCs plus alkylating agents or RTX are similarly effective as first-line therapy and in the relapse/refractory setting. In patients with EMC, treatment should consist of GCs plus RTX, with the dose of GCs tapered as soon as possible to reduce the risk of infectious complications.

COVID-19 and Mixed Cryoglobulinemia Syndrome: Long-Term Survey Study on the Prevalence and Outcome, Vaccine Safety, and Immunogenicity

PURPOSE

Mixed cryoglobulinemia syndrome (MCs) is a rare immunoproliferative systemic disorder with cutaneous and multiple organ involvement. Our multicenter survey study aimed to investigate the prevalence and outcome of COVID-19 and the safety and immunogenicity of COVID-19 vaccines in a large MCs series.

METHODS

The survey included 430 unselected MCs patients (130 M, 300 F; mean age 70 ± 10.96 years) consecutively collected at 11 Italian referral centers. Disease classification, clinico-serological assessment, COVID-19 tests, and vaccination immunogenicity were carried out according to current methodologies.

RESULTS

A significantly higher prevalence of COVID-19 was found in MCs patients compared to Italian general population (11.9% vs 8.0%, p < 0.005), and the use of immunomodulators was associated to a higher risk to get infected (p = 0.0166). Moreover, higher mortality rate was recorded in MCs with COVID-19 compared to those without (p < 0.01). Patients' older age (≥ 60 years) correlated with worse COVID-19 outcomes. The 87% of patients underwent vaccination and 50% a booster dose. Of note, vaccine-related disease flares/worsening were significantly less frequent than those associated to COVID-19 (p = 0.0012). Impaired vaccination immunogenicity was observed in MCs patients compared to controls either after the first vaccination (p = 0.0039) and also after the booster dose (p = 0.05). Finally, some immunomodulators, namely, rituximab and glucocorticoids, hampered the vaccine-induced immunogenicity (p = 0.029).

CONCLUSIONS

The present survey revealed an increased prevalence and morbidity of COVID-19 in MCs patients, as well an impaired immunogenicity even after booster vaccination with high rate of no response. Therefore, MCs can be included among frail populations at high risk of infection and severe COVID-19 manifestations, suggesting the need of a close monitoring and specific preventive/therapeutical measures during the ongoing pandemic.

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.

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.

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

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

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

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

Mixed cryoglobulinaemic vasculitis with pulmonary infiltrates and cavitation

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

Autoimmune Hepatitis Associated With Cryoglobulinemic Vasculitis

Cryoglobulinemic vasculitis presents liver abnormalities usually associated with hepatitis C. We report a case of a 27-year-old woman with cryoglobulinemia and liver dysfunction secondary to autoimmune hepatitis. The patient developed purpura on the lower extremities and elevated aminotransferases. The investigation of hepatitis C was negative. Autoimmune hepatitis was confirmed by positive ANA, hypergammaglobulinemia, and compatible histological changes. Treatment with prednisone and azathioprine regressed cutaneous vasculitis and decreased aminotransferases. This case describes a rare association of cryoglobulinemic vasculitis and autoimmune hepatitis.

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.

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.

Cutaneous manifestations of monoclonal gammopathy

Monoclonal gammopathy associated with dermatological manifestations are a well-recognized complication. These skin disorders can be associated with infiltration and proliferation of a malignant plasma cells or by a deposition of the monoclonal immunoglobulin in a nonmalignant monoclonal gammopathy. These disorders include POEMS syndrome, light chain amyloidosis, Schnitzler syndrome, scleromyxedema and TEMPI syndrome. This article provides a review of clinical manifestations, diagnostics criteria, natural evolution, pathogenesis, and treatment of these cutaneous manifestations.

Cryoglobulinemia

Cryoglobulins are immunoglobulins that precipitate in vitro at temperatures below 37 ̊C. Cryoglobulin-associated disease is heterogeneous, as not all patients present with it, includes various syndromic presentations (vasculitis is the most common, hyperviscosity syndrome is more exceptional), and can be associated with acute clinical pictures with high mortality. Until the appearance of specific antiviral treatments, the main aetiology has been chronic HCV infection, and currently it is mainly associated with systemic autoimmune diseases, malignant neoplasms and cases with no identified aetiology (essential cryoglobulinemia). Treatment should be modulated according to the predominant etiopathogenesis (vasculitis or hyperviscosity), the severity of internal organ involvement and, especially, the associated underlying disease. Due to the complex aetiological, clinical and pathological scenario of cryoglobulinaemia, early recognition of the most common clinical presentations, a comprehensive clinical assessment of the different organs that may be affected, and multidisciplinary work led by a unit specialised in systemic autoimmune diseases is essential.

Management of nonviral mixed cryoglobulinemia vasculitis refractory to rituximab: Data from a European collaborative study and review of the literature

BACKGROUND

Glucocorticoids (GCs) plus rituximab (RTX) represent the first-line treatment of nonviral mixed cryoglobulinemia vasculitis (CryoVas). However, data on therapeutic management and outcome of patients refractory to RTX are lacking.

METHODS

We conducted a European collaborative retrospective multicenter study of patients with nonviral mixed CryoVas refractory to RTX and performed a literature review.

RESULTS

Twenty-six original cases and 7 additional patients from the literature were included. All patients but one had type 2 cryoglobulinemia, and causes were autoimmune disease (51%), malignant hemopathy (12%) or essential CryoVas (42%). CryoVas was primary refractory to RTX in 42%, while 58% had an initial response to RTX before immune escape. After RTX failure, patients received a median of 1 (IQR, 1-3) line of treatment, representing 65 treatment periods during follow-up. Main treatments used were GCs in 92%, alkylating agents in 43%, RTX in combination with other treatments in 46%, and belimumab in 17%. Combination of anti-CD20 plus belimumab, alkylating agents alone and anti-CD20 plus alkylating agents provided the highest rates of clinical response in 100% 82% and 73%, respectively, but showed poor immunological response, in 50%, 30% and 38%, respectively. Rates of severe infection were 57%, 9% and 0% in patients receiving anti-CD20 plus belimumab, alkylating agents alone and anti-CD20 plus alkylating agents, respectively.

CONCLUSION

In patients with nonviral mixed CryoVas refractory to RTX, anti-CD20 plus belimumab, and alkylating agents associated or not with anti-CD20, provide the highest rates of clinical response. However, anti-CD20 plus belimumab was frequently associated with severe infections.

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.

It Is Just a Rash They Said! Acute Skin Manifestation in a Patient With Vasculitis in Rural Hospitals

A 76-year-old Caucasian male with a history of rheumatoid arthritis, Raynaud’s phenomenon, pulmonary embolism on warfarin, and a previous amputation of his left partial ring and fifth finger presented with acute onset of rash in bilateral lower extremities. He was recently started on trimethoprim-sulfamethoxazole due to concern for cellulitis. Differential diagnosis for acute-onset rash with the patient’s history presented as a challenge to the internist, as the differential is broad. Our case goes through the differential diagnosis to contrast the different presentations of rash in a patient with vasculitis. Ultimately skin biopsy in conjunction with a past positive cryoglobulinemic level helped confirm the diagnosis of cutaneous vasculitis, following which he was started on appropriate treatment and recovered.

Noninfectious, Severe Cryoglobulinemic Vasculitis with Renal Involvement - Safety and Efficacy of Long-Term Treatment with Rituximab

Background

The management of nonviral cryoglobulinemic vasculitis (CV) has not been established yet. Randomized control trials are challenging to perform because of the rarity of the disease. The most promising biological therapy is rituximab (RTX), an anti-CD 20 monoclonal antibody. The aim of the study was to assess rituximab treatment's safety and effectiveness in patients with severe noninfectious cryoglobulinemic vasculitis.

Materials and Methods

We retrospectively reviewed 8 courses of RTX treatment in three patients with severe noninfectious CV. In 2 patients, the indication for the start of RTX therapy was the relapse of the disease despite the maintenance treatment, for the third patient, it was the first-line therapy.

Results

Clinical, renal, and immunologic efficacy was observed in all evaluable RTX courses. We found a significant decrease of cryoglobulins in the 3-rd month from RTX treatment. However, 5 clinical relapses occurred and two patients experienced severe adverse events (SAEs) after RTX therapy. Patients with SAEs were relatively older and had a longer duration of disease. Lower levels of hemoglobin, C3 component of complement and eGFR as well as higher rheumatoid factor (RF) concentration were observed before RTX treatments complicated with SAEs.

Conclusion

Data from our observation show the efficacy of rituximab in the refractory, nonviral cryoglobulinemic vasculitis with a severe course of the disease. However, the therapy is associated with the risk of SAEs, especially in elderly patients with kidney failure and significant immunologic alterations.

Hepatitis B Virus-Related Cryoglobulinemic Vasculitis: Review of the Literature and Long-Term Follow-Up Analysis of 18 Patients Treated with Nucleos(t)ide Analogues from the Italian Study Group of Cryoglobulinemia (GISC)

Hepatitis B virus (HBV) chronic infection causes progressive liver damage, although about 20% of patients develop extrahepatic manifestations such as cryoglobulinemic vasculitis (CV). Clinical manifestations range from mild to moderate (purpura, asthenia, arthralgia) to severe (leg ulcers, peripheral neuropathy, glomerulonephritis, non-Hodgkin lymphoma). A comprehensive review of therapeutic options for HBV-related CV is lacking. Nucleos(t)ide analogues (NA) suppress HBV replication in 90–100% of cases and induce clinical response in most patients with mild-to-moderate CV. Plasma exchange can be performed in patients with severe CV and should be considered in severe or life-threatening cases combined with high doses of corticosteroids and antiviral treatment. A cautious use of rituximab can be considered only in association with NA treatment in refractory cases. A review of the literature and an analysis of data collected by six centers of the Italian Group for the Study of Cryoglobulinemia on 18 HBV-CV nucleotide/nucleoside analogues (NAs)-treated patients were carried out.

Cryoglobulins, Cryofibrinogens, and Cold Agglutinins in Cold Urticaria: Literature Review, Retrospective Patient Analysis, and Observational Study in 49 Patients

Introduction

Cryoproteins, such as cryoglobulins, cryofibrinogens and cold agglutinins, precipitate at low temperatures or agglutinate erythrocytes and dissolve again when warmed. Their pathogenetic and diagnostic importance in cold urticaria (ColdU) is unclear. In this study, we aimed to characterize the prevalence of cryoproteins in patients with ColdU.

Methods

We conducted 3 analyses: i) a systematic review and meta-analysis of published data using an adapted version of the Joanna Briggs Institute's critical appraisal tool for case series, ii) a retrospective analysis of 293 ColdU patients treated at our Urticaria Center of Reference and Excellence (UCARE) from 2014 to 2019, and iii) a prospective observational study, from July 2019 to July 2020, with 49 ColdU patients as defined by the EAACI/GA2LEN/EDF/UNEV consensus recommendations.

Results

Our systematic review identified 14 relevant studies with a total of 1151 ColdU patients. The meta-analyses showed that 3.0% (19/628), 1.1% (4/357) and 0.7% (2/283) of patients had elevated levels of cryoglobulins, cryofibrinogens and cold agglutinins, respectively. Our retrospective analyses showed that cryoproteins were assessed in 4.1% (12/293) of ColdU patients. None of 9 ColdU patients had cryoglobulins, and one of 5 had cold agglutinins. In our prospective study, none of our patients had detectable cryoglobulins (0/48) or cryofibrinogens (0/48), but 4.3% (2/46) of patients had cold agglutinins (without any known underlying autoimmune or hematological disorder).

Conclusion

Our investigation suggests that only very few ColdU patients exhibit cryoproteins and that the pathogenesis of ColdU is driven by other mechanisms, which remain to be identified and characterized in detail.

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.

Clinical Spectrum and Renal Outcome of Cryoglobulinemia in Hong Kong

Background

Cryoglobulinemia is a systemic disease and the clinical involvement is variable. The long-term renal outcome of cryoglobulinemia remains unclear, and most published series are from the Western world, with a high proportion of chronic hepatitis C. The objective is to determine the prevalence, causes, and renal outcome of cryoglobulinemia in Hong Kong.

Methods

We reviewed 289 patients with cryoglobulinemia in the public hospital database of Hong Kong between 2000 and 2019. The renal event-free survival, dialysis-free survival, and overall survival were analyzed according to the underlying etiologies, and compared with 7483 patients who tested negative for cryoglobulinemia during the same period.

Results

Among the patients with cryoglobulinemia, 68 (24%) had chronic hepatitis B, 69 (24%) had hepatitis C, and 14 (5%) paraproteinemia. They were followed for 62.7±58.0 months. The 5-year dialysis-free survival was 68%, 70%, 67%, and 83% for patients with cryoglobulinemia attributed to hepatitis B, hepatitis C, paraproteinemia, and unknown etiology, respectively (P=0.05), and their 5-year overall survival was 61%, 58%, 22%, and 72%, respectively (P=0.002). Among patients with hepatitis B, the group with cryoglobulin had a worse renal event-free survival than those without (36% versus 43%, P=0.005), although their dialysis-free survival and all-cause mortality were similar. For patients with hepatitis C or paraproteinemia, the presence of cryoglobulin did not affect the renal outcome.

Conclusions

Hepatitis B is a common cause of cryoglobulinemia in southeast Asia, and the presence of cryoglobulinemia is associated with a worse renal event-free survival. The renal prognosis of cryoglobulinemia appears to be affected by the underlying cause, with hepatitis B having a worse renal outcome and patients with paraproteinemia having a worse overall survival than those with other causes of 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.

Mixed Cryoglobulinemia Syndrome (MCS) due to untreated hepatitis B with uncommon presentation: case report and literature review

Background

The mixed cryoglobulinemia (MC) syndrome is a systemic inflammatory syndrome that causes small-to-medium vessel vasculitis due to cryoglobulin-containing immune complexes most commonly caused by chronic hepatitis C virus (HCV), and rarely by chronic hepatitis B virus (HBV). Its clinical presentation is significantly varied, with manifestations ranging from purpura, arthralgia, and myalgia to more severe neurologic and renal involvement. Pulmonary involvement as organizing pneumonia, alveolar hemorrhage, and pulmonary vasculitis have been reported, but appear to be quite rare.

Case presentation

We report an uncommon case of a patient who presented with primary pulmonary syndrome without renal involvement in the setting of MC, due to untreated chronic hepatitis B infection. Early diagnosis and consequent institution of glucocorticoids, B-cell-depleting monoclonal antibody and antiviral therapy led to a favorable outcome and prevented any fatal sequelae.

Conclusion

Pulmonary compromise in MC syndrome is very uncommon and carries a high rate of mortality. Therefore, in patients with HBV presenting with hemoptysis, physicians must carry a high clinical suspicion for alveolar hemorrhage secondary to cryoglobulinemic vasculitis.

Delayed diagnosis of Angioimmunoblast T-cell lymphoma presenting with type II Cryoglobulinemia and acute kidney injury: a case report and narrative review of the literature

Background

Angioimmunoblastic T cell lymphoma (AITL) is an infrequent hematological malignancy with variable and often atypical presentations. The presence of dysproteinemia, autoantibodies and systemic involvement in AITL has often led to a delay in diagnosis or even misdiagnosis in practice. We herewith present a case of AITL that primarily presented with acute kidney injury associated with type II Cryoglobulinemia, the underlying cause was only identified 8 months after the emergence of initial symptoms.

Case presentation

A 67-year old woman presented with 2-month history of intermittent joint pain and a 3-day history of bilateral lower limb edema and acute kidney injury. Initial laboratory investigations showed marked hypocomplementemia with positive autoantibodies of ANA, anti-cardiolipin-IgM and direct antiglobulin. The serum and urinary Immunofixation and serum cryoglobulin tests were negative, while the serum free κ to λ light chain ratio was 0.231. A renal biopsy showed a diffuse proliferative glomerulonephritis with intracapillary pseudothrombi formation. There were orderly arranged microtubular structures of 20–35 nm in diameter in the subendothelial and mesangial area on electron microscopy. Shortly afterwards, the patient developed tingling affecting her finger tips and weak hands and legs. A diagnosis of cryoglobulinemia complicated with cryoglobulinemic glomerulonephritis and polyneuropathy was made. She responded well to methylprednisolone, plasma exchange and rituximab. However, 3 months later, she presented with generalized pruritic rash, weight loss, and inguinal lymphadenopathy. A subsequent inguinal excisional lymph node biopsy at month 8 revealed AITL as the underlying disease.

Conclusions

AITL and its associated B cell dysregulation can give rise to autoimmunity and cryoglobulinemia which may conceal itself as the underlying disorder. In various clinical scenarios of auto-immune diseases, it is advisable that the clinicians should take into consideration the multi-faceted lymphoma.

Cryoglobulinemic vasculitis in primary Sjögren's Syndrome: Clinical presentation, association with lymphoma and comparison with Hepatitis C-related disease

OBJECTIVE

To describe the clinical spectrum of cryoglobulinemic vasculitis (CV) in primary Sjögren's syndrome (pSS), investigate its relation to lymphoma and identify the differences with hepatitis C virus (HCV) related CV.

METHODS

From a multicentre study population of consecutive pSS patients, those who had been evaluated for cryoglobulins and fulfilled the 2011 classification criteria for CV were identified retrospectively. pSS-CV patients were matched with pSS patients without cryoglobulins (1:2) and HCV-CV patients (1:1). Clinical, laboratory and outcome features were analyzed. A data driven logistic regression model was applied for pSS-CV patients and their pSS cryoglobulin negative controls to identify independent features associated with lymphoma.

RESULTS

1083 pSS patients were tested for cryoglobulins. 115 (10.6%) had cryoglobulinemia and 71 (6.5%) fulfilled the classification criteria for CV. pSS-CV patients had higher frequency of extraglandular manifestations and lymphoma (OR=9.87, 95% CI: 4.7-20.9) compared to pSS patients without cryoglobulins. Purpura was the commonest vasculitic manifestation (90%), presenting at disease onset in 39% of patients. One third of pSS-CV patients developed B-cell lymphoma within the first 5 years of CV course, with cryoglobulinemia being the strongest independent lymphoma associated feature. Compared to HCV-CV patients, pSS-CV individuals displayed more frequently lymphadenopathy, type II IgMk cryoglobulins and lymphoma (OR = 6.12, 95% CI: 2.7-14.4) and less frequently C4 hypocomplementemia and peripheral neuropathy.

CONCLUSION

pSS-CV has a severe clinical course, overshadowing the typical clinical manifestations of pSS and higher risk for early lymphoma development compared to HCV related CV. Though infrequent, pSS-CV constitutes a distinct severe clinical phenotype of pSS.

Recent news in the treatment of hepatitis B virus-related cryogobulinemic vasculitis

Hepatitis B virus (HBV) is a hepatotropic virus that causes hepatitis, cirrhosis and hepatocellular carcinoma. Twenty percent of HBV patients may develop extra-hepatic manifestations, such as polyarthritis nodosa, glomerulonephritis, dermatitis, poly-arthralgia and arthritis, and aplastic anemia. The association of HBV and cryoglobulinemic vasculitis (CV) has been highlighted by several epidemiological investigations. CV can develop in 0.5-4% of HBV infected patients. It has been demonstrated that suppression of HBV replication by nucleot(s)ide analogues (NAs) effectively induces clinical response in most patients with mild to moderate CV, but low responses are seen in severe CV. Based on this evidence, NAs therapy represents the first line therapeutic option in subjects with mild or moderate HBV related CV. Peg-interferon-Alfa can be an alternative treatment for HBV related CV, but the few studies published so far have shown no encouraging results. In patients with severe vasculitis and/or skin ulcers, peripheral neuropathy and glomerulonephritis treatment with rituximab (RTX) and NAs should be considered as a first line treatment. The long-term administration of low-medium glucocorticoid doses has been widely used in few studies to control clinical symptoms, but it should be used as a second option, when RTX is ineffective or not tolerated and in association with NAs. This review focuses on novel treatments for HBV related CV.

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.

An update to the pathogenesis for monoclonal gammopathy of renal significance

Monoclonal gammopathy of renal significance (MGRS) is characterized by the nephrotoxic monoclonal immunoglobulin secreted by an otherwise asymptomatic or indolent B cell or plasma cell clone, without hematologic criteria for treatment. These MGRS-associated diseases can involve one or more renal compartments, including glomeruli, tubules, and vessels. Hydrophobic residue replacement, N-glycosylated, increase in isoelectric point in monoclonal immunoglobulin (MIg) causes it to transform from soluble form to tissue deposition, and consequently resulting in glomerular damage. In addition to MIg deposition, complement deposition is also found in C3 glomerulopathy with monoclonal glomerulopathy, which is caused by an abnormality of the alternative pathway and may involve multiple factors including complement component 3 nephritic factor, anti-complement factor auto-antibodies, or MIg which directly cleaves C3. Furthermore, inflammatory factors, growth factors, and virus infection may also participate in the development of the diseases. In this review, for the first time, we discussed current highlights in the mechanism of MGRS-related lesions.

Direct-acting antiviral therapy improves kidney survival in hepatitis C virus-associated cryoglobulinaemia: the RENALCRYOGLOBULINEMIC study

Background

Direct-acting antiviral agents (DAAs) have shown high rates of sustained virological response in chronic hepatitis C virus (HCV) infection. However, the influence of DAAs on the course of kidney involvement in HCV-associated mixed cryoglobulinaemia (HCV-MC) has been little studied. The aim of this study was to analyse the effects of antiviral treatment on kidney prognosis and evolution in patients diagnosed with HCV-MC.

Methods

The RENALCRYOGLOBULINEMIC study is an observational multicentre cohort study of 139 patients with HCV-MC from 14 Spanish centres. Clinical and laboratory parameters were measured before and after antiviral treatment. Primary endpoints were kidney survival and mortality after HCV-MC diagnosis. Secondary endpoints were clinical, immunological and virological responses after antiviral treatment.

Results

Patients were divided into three groups based on the treatment received: treatment with DAAs (n = 100) treatment with interferon (IFN) and ribavirin (RBV) (n = 24) and no treatment (n = 15). Patients were followed up for a median duration of 138 months (interquartile range 70-251. DAA treatment reduced overall mortality {hazard ratio [HR] 0.12 [95% confidence interval (CI) 0.04-0.40]; P < 0.001} and improved kidney survival [HR 0.10 ( 95% CI 0.04-0.33); P < 0.001].

Conclusions

Results from the RENALCRYOGLOBULINEMIC study indicated that DAA treatment in patients with HCV-MC improves kidney survival and reduces mortality.

Positive acute viral infection markers, autoimmune disease and type II mixed cryoglobulinemia: a rare concurrence

Cryoglobulins are abnormal serum immunoglobulins that tend to precipitate in intravascular compartments at temperatures lower than 37°C causing blood flow restriction to vital organs. They are divided into type I, II and III based on the immunoglobulin subtypes of the cryoprecipitates. Type II cryoglobulinemia is most commonly associated with viral infections, autoimmune diseases and lymphoproliferative disorders. Here, we reported an 80-year-old man who presented with fatigue, acute kidney injury, palpable purpura, anaemia and altered mental status. He was diagnosed with type II cryoglobulinemia with concomitant positive autoimmune markers, varicella IgM antibody and IgM hepatitis B core antibody. The patient responded well to intravenous and oral steroid treatment.

Cryoglobulins Today: Detection and Immunologic Characteristics of 1,675 Positive Samples From 13,439 Patients Obtained Over Six Years

OBJECTIVE

Cryoglobulins are cold-precipitating immunoglobulins. Through progress in techniques, we undertook this study to update information on the biologic characteristics of cryoglobulins in a very large population.

METHODS

A cohort of 13,439 patients was tested for cryoglobulins from January 2010 to December 2016. The analysis included cryoglobulin isotype, clonality, concentration, and IgM rheumatoid factor (IgM-RF) in cryoprecipitate, as well as serum complement and RF. Markers of gammopathy, viral infection, and autoimmunity were also investigated.

RESULTS

Of the 13,439 patients, 1,675 (12.5%) tested positive for cryoglobulins: 155 patients (9.3%) with type I, 788 (47%) with type II, and 732 (43.7%) with type III cryoglobulins. Nine percent of patients who were retested after initially testing negative for cryoglobulins showed a positive result on a follow-up test (196 of the 2,213 retested patients). In type I cryoglobulins, IgM was more frequent but occurred at lower concentrations than IgG. Mixed cryoglobulins were found in 34.8% of the tested patients who were positive for hepatitis C virus and <5% of those who were positive for hepatitis B virus or HIV. Of the patients with anti-double-stranded DNA, anti-SSA, or anti-cyclic citrullinated peptide autoantibodies, 25.4% tested positive for mixed cryoglobulins, with type III occurring more frequently than type II. Both cryoprecipitate and serum were RF-positive in 21.6% of type II and 10.1% of type III cryoglobulins. A decrease of C4, with or without accompanying decreases of C3 and CH50, was found in 23.6% of cryoglobulin samples.

CONCLUSION

Obtained with the use of modern assays, our findings from this very large collection of cryoglobulins provide an update on cryoglobulin distribution and characteristics, with minimal selection bias. Despite strict preanalytical conditions, a negative finding for the presence of cryoglobulin must be confirmed in a second sample. RF activity and complement decreases were rarely detected.

Hepatitis B virus-related cryogobulinemic vasculitis. The role of antiviral nucleot(s)ide analogues: a review

Cryoglobulinemic vasculitis (CV) can develop in 1.2-4% of hepatitis B virus (HBV)-infected patients. HBV infection affects about 350 million people worldwide. It can progress from acute or fulminant hepatitis to chronic hepatitis, cirrhosis or hepatocellular carcinoma. Twenty per cent of HBV patients may develop extra-hepatic manifestations, such as polyarteritis nodosa, glomerulonephritis, dermatitis, polyarthralgias and arthritis, lung disease, aplastic anaemia. Our review focuses on the role of antiviral agent nucleot(s)ide analogues (NAs) in treatment of HBV-related CV. The studies in literature have demonstrated that NAs therapy in HBV-related CV yields high virological and satisfying clinical responses in most patients with mild-and-moderate CV, but a low response in severe CV. Overall, NAs represent a promising therapeutic option for HBV-related CV. Obtaining early suppression of HBV viral load should be the main virological and clinical goal in order to prevent organ complications and lymphoproliferative disorders.

New insights in cryoglobulinemic vasculitis

Cryoglobulins are antibodies that precipitate at low temperatures and dissolve after rewarming. Cryoglobulinemia refers to the presence of circulating cryoglobulins and generally leads to a systemic inflammatory syndrome characterized by fatigue, arthralgia, purpura, ulcers, neuropathy and/or glomerulonephritis. The disease mainly involves small to medium-sized blood vessels and causes vasculitis due to cryoglobulin-containing immune complexes. Cryoglobulinemia is classified into three types (I, II and III) on the basis of immunoglobulin composition. Predisposing conditions include lymphoproliferative, autoimmune diseases and hepatitis C virus infection. The diagnosis of cryoglobulinemic syndrome is predominantly based on the presence of clinical features and laboratorial demonstration of serum cryoglobulins. The treatment strategy depends on the cause of cryoglobulinemia. For patients with chronic HCV infection, antiviral therapy is indicated. Immunosuppressive or immunomodulatory therapy, including steroids, plasmapheresis and cytotoxic agents, is reserved for organ-threatening manifestations. In this review, we discuss the main clinical presentations, diagnostic approach and treatment options.

Cryoglobulinemic vasculitis and glomerulonephritis: concerns in clinical practice

OBJECTIVE

Cryoglobulinemia often causes systemic vasculitis, thereby damaging to skin and internal organs including kidneys, even life-threatening. This review aimed to introduce the advances in understanding, detection, and treatment of this disease in recent years, with a particular concern to clinical practice.

DATA SOURCES

All the data in this review were from the English or Chinese literature in the PubMed and China National Knowledge Infrastructure databases as of March 2019.

STUDY SELECTION

This review selected important original articles, meaningful reviews, and some reports on cryoglobulinemia published in recent years and in history, as well as the guidelines for treatment of underlying diseases which lead to cryoglobulinemia.

RESULTS

Diagnosis of cryoglobulinemia relies on serum cryoglobulin test, in which to ensure that the blood sample temperature is not less than 37°C in the entire pre-analysis phase is the key to avoid false negative results. Cryoglobulinemic vasculitis (Cryo Vas), including cryoglobulinemic glomerulonephritis (Cryo GN), usually occurs in types II and III mixed cryoglobulinemia, and can also be seen in type I cryoglobulinemia caused by monoclonal IgG3 or IgG1. Skin purpura, positive serum rheumatoid factor, and decreased serum levels of C4 and C3 are important clues for prompting types II and III Cryo Vas. Renal biopsy is an important means for diagnosis of Cryo GN, while membranous proliferative GN is the most common pathological type of Cryo GN. In recent years, great advances have been made in the treatment of Cryo Vas and its underlying diseases, and this review has briefly introduced these advances.

CONCLUSIONS

Laboratory examinations of serum cryoglobulins urgently need standardization. The recent advances in the diagnosis and treatment of Cryo Vas and GN need to be popularized among the clinicians in related disciplines.

Hepatitis C virus - related cryoglobulinemic vasculitis with renal involvement current possibilities of diagnostic and treatment

The extrahepatic manifestations of HCV infections, which include mixed cryoglobulinemia (MC), are important for prognosis and determination of the treatment options of these patients. Currently, mixed MC type II is considered as a specific marker of chronic HCV infection. Kidney damage is one of the severe, often determining a prognosis of extrahepatic manifestation of HCV-associated cryoglobulinemic vasculitis. The review discusses the current diagnostic approaches to cryoglobulinemic GN, as well as perspectives for improving antiviral and pathogenetic therapy.

Treatment of hepatitis C virus infection in patients with mixed cryoglobulinemic syndrome and cryoglobulinemic glomerulonephritis

Cryoglobulinemia is a common extrahepatic manifestation of infection with hepatitis C virus (HCV). When signs and symptoms of systemic vasculitis or glomerulonephritis occur in the presence of circulating cryoglobulins, this syndrome is called "mixed cryoglobulinemia syndrome" (MCS). Historically, interferon-based therapies in HCV have been associated with lower rates of viral cure in patients with MCS than in the general HCV-infected population. The advent of direct-acting antiviral therapies have revolutionized the treatment of HCV, dramatically increasing rates of cure. Early studies of first-generation protease inhibitors (telaprevir and boceprevir) in combination with interferon and ribavirin demonstrated HCV cure rates of 67% and complete clinical response rates of vasculitis symptoms in 60% of patients with MCS; however, regimens were poorly tolerated by patients, 22% discontinued treatment early. More recently, all-oral, interferon-free regimens have become available and combination therapies are now being approved for patients with and without renal impairment. Patients with HCV-MCS achieved sustained virologic response in 297 out of 313 patients (95%) treated with direct-acting antiviral therapy, and 85% had a complete or partial clinical response of MCS symptoms. Current direct-acting antiviral therapies are well tolerated in patients with HCV-MCS and only 1.6% discontinued treatment early. Patients with cryoglobulinemic glomerulonephritis also had an excellent cure rate (94%). The majority improved; 17/52 (33%) experienced full remission and 15/52 (29%) experienced partial remission. There were no reports of worsening kidney function in patients treated with direct-acting antiviral therapies. Less than 5% of patients with HCV-MCS treated with IFN-free direct-acting antiviral therapy required immunosuppression. However, patients with severe vasculitis appear to still require concomitant immunosuppression.