High prevalence of past hepatitis B virus infection in diffuse large B cell lymphoma: a retrospective study from Italy.

Studies from high endemic areas, mostly China, indicate that surface antigen positive (HBsAgpos) chronic hepatitis B virus (HBV) infection is associated with an increased risk of developing diffuse large B-cell lymphoma (DLBCL), whereas studies in low endemic areas have provided conflicting results. Past infection, serologically defined by negative HBsAg and positive anti-core antibody (HBsAgnegHBcAbpos), has also been suggested to increase the risk of B-cell non-Hodgkin's lymphoma (NHL) in high endemic areas. We retrospectively reviewed unselected clinical records of 253 patients with DLBCL (54% male, aged 60.3 ± 14.6 years at diagnosis) and 694 patients with different types of indolent B-cell NHL (46% male, aged 61.7 ± 12.8 years). Patients were seen at a single center in Italy between 2001 and 2022 and HBV serological status (HBsAg, HBsAb, HBcAb, HBeAg, HBeAb, and HBV DNA) was analyzed through enzyme-linked immunosorbent assays and molecular assays; patients infected with hepatitis C virus or human immunodeficiency virus were excluded. We used an unconditional multiple logistic regression model including as matching variables gender, age at diagnosis, immigrant status, and HBV serological status. Patients with DLBCL had, compared to indolent NHL, a higher prevalence of HBsAgpos active infection (odds ratio (OR) 2.8, 95% confidence interval (95% CI) 1.2-6.3, p = 0.014). Strikingly, patients with DLBCL had also a significantly higher prevalence of past infection (OR 2.4, 95% CI 1.5-4.0, p = 0.0006). Male gender was associated with increased risk of DLBCL independently of the HBV serological status. These findings suggest that both past and active HBV infection may increase the risk of DLBCL in a low endemic area. Our study needs confirmation by studies in areas or populations with different rates of chronic or past HBV infection.

Persistence of monoclonal B-cell expansion and intraclonal diversification despite virus eradication in patients affected by hepatitis C virus-associated lymphoproliferative disorders.

We investigated 23 hepatitis C virus (HCV)-infected patients with overt lymphoproliferative diseases (15 cases) or monoclonal B lymphocytosis (8 cases) treated with direct agent antiviral (DAAs) per clinical practice. DAA therapy yielded undetectable HCV-RNA, the complete response of cryoglobulinemia vasculitis and related signs, whilst the presence of B-cell clones (evaluated by flow cytometry, IGHV, and BCL2-IGH rearrangements), detected in 19/23 cases at baseline, was maintained (17/19). Similarly, IGHV intraclonal diversification, supporting an antigen-driven selection mechanism, was identified in B-cell clones at baseline and end of follow-up. DAA therapy alone, despite HCV eradication and good immunological responses, was less effective on the pathological B-cell clones.

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.

Management of mixed cryoglobulinemia with rituximab: evidence and consensus-based recommendations from the Italian Study Group of Cryoglobulinemia (GISC).

Cryoglobulinemic vasculitis (CV) or mixed cryoglobulinemic syndrome (MCS) is a systemic small-vessel vasculitis characterized by the proliferation of B-cell clones producing pathogenic immune complexes, called cryoglobulins. It is often secondary to hepatitis C virus (HCV), autoimmune diseases, and hematological malignancies. CV usually has a mild benign clinical course, but severe organ damage and life-threatening manifestations can occur. Recently, evidence in favor of rituximab (RTX), an anti-CD 20 monoclonal antibody, is emerging in CV: nevertheless, questions upon the safety of this therapeutic approach, especially in HCV patients, are still being issued and universally accepted recommendations that can help physicians in MCS treatment are lacking. A Consensus Committee provided a prioritized list of research questions to perform a systematic literature review (SLR). A search was made in Medline, Embase, and Cochrane library, updated to August 2021. Of 1227 article abstracts evaluated, 27 studies were included in the SLR, of which one SLR, 4 RCTs, and 22 observational studies. Seventeen recommendations for the management of mixed cryoglobulinemia with rituximab from the Italian Study Group of Cryoglobulinemia (GISC) were developed to give a valuable tool to the physician approaching RTX treatment in CV.

COVID-19 vaccination rate and safety profile in a multicentre Italian population affected by mixed cryoglobulinaemic vasculitis.

OBJECTIVES: Mixed cryoglobulinaemic vasculitis (MCV) is an immune-complex-mediated systemic vasculitis characterised by heterogeneous clinical manifestations mainly involving lymphatic system, skin, kidney and peripheral nervous system. Although MCV patients have been included in priority programs for vaccination against SARS-CoV-2 in Italy, limited information is available for these patients. The aims of this multicentre Italian study were to investigate SARS-CoV-2 vaccination rate in MCV patients and its safety profile. METHODS: All MCV patients referring to participating centres were assessed with an interview-based survey about vaccination, reasons for not getting vaccinated, adverse events (AE), and disease flares within a month after vaccination. RESULTS: A total of 416 patients were included in the study. Among participants, 7.7% did not get vaccinated, mainly for fear related to vaccine side-effects (50%) or medical decision (18.8%). They were more frequently treated with chronic glucocorticoids or rituximab (p=0.049 and p=0.043, respectively). Mild and self-limiting AE were recorded in 31.7% of cases, while post-vaccination vasculitis flares were observed in 5.3% of subjects. Disease relapses were mainly observed in patients with peripheral neuropathy or skin vasculitis (40% and 25%, respectively). CONCLUSIONS: Vaccination against SARS-CoV-2 has been performed in a high percentage of MCV patients with encouraging safety profile. Vasculitis flares rate was in line with that observed for other autoimmune diseases, despite patients with purpura or peripheral neuropathy seem to be at risk for symptoms' exacerbation. Patients' hesitancy, rituximab and glucocorticoids treatment were the main reasons for delaying vaccination.

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.

Hepatitis C virus-associated B-cell lymphomas: The importance of the new direct antiviral agent therapy.

Hepatitis C virus (HCV) is a hepatotropic and lymphotropic virus, responsible for both chronic hepatitis and extra-hepatic manifestations. Multiple epidemiologic, clinical, biological, and molecular studies have suggested that HCV plays a causal role also in the development of several lymphoproliferative disorders, either benign, such as mixed cryoglobulinemia, or malignant, such as B-cell non-Hodgkin lymphomas (NHL). Chronic viral antigenic stimulation of B-lymphocytes plays a fundamental basic role from the onset of lymphoma to its final steps. In the past, several studies demonstrated that the association of pegylated interferon plus ribavirin was able to eradicate HCV, with subsequent regression of indolent B-cell low-grade NHL. Other studies have demonstrated that direct antiviral agents (DAAs) therapy have some efficacy in HCV-associated NHL, particularly in patients with low-grade NHL or marginal zone-lymphoma, but these results need to be confirmed in larger studies with longer follow-up. The response rate of antiviral therapy seems favorable also in high grade NHL when DAAs therapy is administered in combination with chemotherapy and therefore antiviral therapy should be considered as a first-line approach in HCV-related NHL.

A Review on Extrahepatic Manifestations of Chronic Hepatitis C Virus Infection and the Impact of Direct-Acting Antiviral Therapy.

Extrahepatic manifestations are a feature of chronic hepatitis C virus (HCV) infection. In the course of chronic HCV infection, about 70% of patients have one or more extrahepatic manifestations. The latter are often the first and only clinical sign of infection. Experimental and clinical data support a causal association for many extrahepatic manifestations and HCV infection, which include mixed cryoglobulinemia, non-Hodgkin lymphomas (NHL), cardiovascular disease, insulin resistance, type 2 diabetes, neurological and psychiatric disease and other rheumatic diseases. All these extrahepatic conditions influence the morbidity, quality of life and mortality of HCV-infected patients. Currently, interferon-free therapeutic regimens with direct-acting antiviral agents (DAA) offer the possibility of treatment to almost the entire infected population, irrespective of stage of cirrhosis and associated serious comorbidities, always maintaining a high efficacy and tolerability. Several studies have shown a close association between HCV clearance by DAAs and an improvement or reduction in the risk of extrahepatic manifestations. Patients with HCV after a sustained virologic response (SVR) by DAA treatment have a lower risk than non-responders of developing cryoglobulinemic vasculitis and B-cell non-Hodgkin's lymphomas. Furthermore, the SVR by DAA also reduces the risk of acute coronary syndrome, cardiovascular disease, insulin resistance and type 2 diabetes, and it improves atherosclerosis. HCV clearance by DAA also improves the quality of life and survival of patients with chronic HCV infection with associated extrahepatic diseases. Thus, DAAs should be initiated as early as possible in HCV patients with extrahepatic manifestations.

Hepatitis C virus-associated indolent B-cell lymphomas: A review on the role of the new direct antiviral agents therapy.

Several studies have suggested that hepatitis C virus (HCV) may be the causative agent of some B-cell non-Hodgkin lymphomas (B-NHL). Several authors have demonstrated that pegylated interferon (Peg-IFN) plus ribavirin (RBV) can revert indolent low-grade B-NHL by inducing HCV eradication. Presently, the combination therapy (IFN plus RBV) has been abandoned since the direct antiviral agents (DAAs) have shown very high efficacy in achieving sustained virologic response (SVR) (range: 95%-100%). This review analyzed DAAs efficacy in HCV-associated indolent low-grade NHL, providing a detailed literature review. Overall, 122 B-cell NHL patients were treated with DAAs: complete/partial hematological response, particularly in those with marginal zone lymphoma, was obtained in most cases. Hematological response, obtained either with DAAs or IFN-based therapy, was similar. Nonetheless, DAAs therapy showed better tolerability and higher SVR. A fraction of the patients, despite SVR, underwent hematologic relapse or progression. In these cases, a recovery treatment with immunotherapy, or chemoimmunotherapy, had to be planned. In conclusion, data obtained from published studies mostly agree that HCV eradication with DAAs should be considered as the first-line treatment in HCV-related NHL. In fact, the chronic viral stimulation of the immune system might be the primary pathogenic mechanism in disease development and progression.

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.

Hepatitis C virus-related cryoglobulinemic vasculitis.

INTRODUCTION: Hepatitis C virus (HCV) infection affects about 170 million people worldwide. HCV is responsible for both hepatitis and extra-hepatic manifestations. Chronic infection has been shown to develop in about 70% of cases, and it can progress to cirrhosis or hepatocellular carcinoma. Ten percent of HCV patients may develop extra-hepatic manifestations, including mixed cryoglobulinemia (MC) and non-Hodgkin lymphomas (NHL). Cryoglobulinemic vasculitis (CV) varies, ranging from mild-moderate clinical symptoms (purpura on the legs, asthenia and arthralgias) and chronic hepatitis to severe symptoms (ulcers on the legs, peripheral neuropathy, glomerulonephritis, low-grade NHL to life threatening complications (rapid progressive glomerulonephritis, gastrointestinal vasculitis, acute hyper-viscosity). EVIDENCE ACQUISITION: CV is associated with significant morbidity and mortality. Some studies have shown kidney involvement, cirrhosis, central nervous system involvement, and heart involvement as unfavorable prognostic factors. Many studies have demonstrated that, after antiviral therapy, CV can disappear along with HCV. After the introduction of the new direct antiviral agents (DAAs), the combination of pegylated interferon and ribavirin has been abandoned. EVIDENCE SYNTHESIS: Several studies on new DAAs have reported remarkable 90% to 100% HCV eradication rates, regardless of genotype. Treatment with DAAs has comparable efficacy on viral eradication in CV patients but definite clinical improvements of vasculitis can be observed only in half the patients. CONCLUSIONS: In patients with mild to moderate CV disease, DAAs therapy should be used as first line approach. In patients with severe vasculitis, DAAs therapy and a second-line treatment with RTX with or without aphaeresis are a required.

Hepatitis C virus-associated non-Hodgkin lymphomas: the endless history.

Hepatitis C virus (HCV) is a global population problem due to its high prevalence worldwide. In the prognosis of patients with HCV not only hepatic but increasingly frequent of extrahepatic HCV manifestations, such as mixed cryoglobulinemia (MC) and non-Hodgkin's lymphoma (NHL), are important. The role of the HCV virus in the pathogenesis of lymphoproliferative diseases is confirmed by a large number of epidemiological studies, as well as by the effectiveness of antiviral therapy in patients with non-Hodgkin's lymphoma (NHL). The purpose of the review was to provide an overview of epidemiological and biological data explaining the role of HCV in the development of NHL. The review also discusses HCV-associated NHL treatment by the traditional antiviral therapy (interferon and ribavirin) and by the new direct antiviral agents.

Direct-acting antiviral agents for hepatitis C virus-mixed cryoglobulinaemia: dissociated virological and haematological responses.

The hepatitis C virus-positive (HCV+) mixed cryoglobulinaemia (MC) is associated with haematological alterations such as monoclonal B-cell lymphocytosis or non-Hodgkin lymphomas (NHLs). Antiviral therapy for MC, based on interferon and ribavirin, has been shown to be able to eliminate the viral replication as well as the B-cell monoclonal alterations. Many studies have reported the efficacy of direct-acting antivirals (DAAs) in the treatment of HCV+ MC. However, some authors noticed the persistence of haematological diseases despite HCV eradication. To verify the effects of DAAs on B-cell proliferation, we evaluated 67 patients with HCV+ MC. Six patients had an overt NHL and 30% had monoclonal B-lymphocytosis. In 20% of the patients, the mutation L265P of the myeloid differentiation factor 88 (MYD88) gene was detected in peripheral blood. All patients had negative HCV viraemia at week 12; one had a breakthrough, while two cases relapsed. A complete clinical response of vasculitis was seen in 60% of the patients. Among the six patients with NHL, one showed a complete response, whereas in the others there were no changes in the number and size of the nodes. Among the patients carrying a clonal population in peripheral blood, only 22% became negative. These data indicate that DAAs are not able to eliminate the clonal alterations induced by HCV in a large proportion of cases.

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.

Hepatitis C virus- related cryoglobulinemic vasculitis: A review of the role of the new direct antiviral agents (DAAs) therapy.

Hepatitis C virus (HCV) infection affects about 70 million people worldwide. HCV is responsible for both hepatitis and extra-hepatic manifestations. Chronic infection has been shown to develop in about 70% of cases and can progress to cirrhosis or hepatocellular carcinoma. Ten percent of HCV patients may develop extra-hepatic manifestations, including mixed cryoglobulinemia (MC) and non-Hodgkin lymphomas. Many studies have demonstrated that, after antiviral therapy, MC can disappear along with HCV eradication. After the introduction of the new direct antiviral agents (DAAs), the combination of pegylated interferon and ribavirin has been abandoned. Several studies on new DAAs have reported remarkable 90% to 100% eradication rates, regardless of HCV genotype. Treatment with DAAs has comparable efficacy on viral eradication in patients with MC, but definite clinical improvements of vasculitis can be observed only in half the patients. On the contrary, the regression of renal disease and lympho-proliferative disorders, induced by HCV, appears to have a lower remission rate after viral eradication with DAAs and most cases need immunosuppressive treatments. In HCV related CV, the main clinical goal must be early eradication of HCV, to avoid organ complication and manifestation of lympho-proliferative diseases. This review focuses on the role of DAAs in treatment of HCV-related cryoglobulinemic vasculitis.

Survival and Prognostic Factors in Mixed Cryoglobulinemia: Data from 246 Cases.

INTRODUCTION: The clinical and therapeutic management of mixed cryoglobulinemia (MC) remains a subject of controversy. In addition, most studies have not recorded the long-term follow-up and the outcome of these cases. MATERIAL AND METHODS: We enrolled 246 patients affected by MC who were consecutively admitted to our Department from January 1993 to February 2013. Clinical and biological data had been recorded until June 2014. RESULTS: The median age (at diagnosis) was 60 years (range 26⁻83). The aetiology was HCV in 95% of patients, HBV in 3% and “essential” in 2%. HCV genotype was 1b in 57%, genotypes 2⁻3 in 43%. MC was Type II in 203 of the cases (87%) and Type III in 52 (13%). The most frequent clinical manifestations were purpura (72%), chronic liver disease (70%), glomerulonephritis (35%), arthralgias (58%), peripheral neuropathy (21%), non-Hodgkin lymphoma (15%) and cutaneous ulcers (3%). Purpura, arthralgias, peripheral neuropathy, glomerulonephritis and non-Hodgkin lymphoma were more frequently observed in Type II than in Type III MC (p < 0.05). Treatments were interferon (IFN) or Pegilated-IFN (PEG-IFN) alone or plus Ribavirin (RIBA) in 101 cases, steroids with or without alkylating agents in 33 cases, Rituximab in 8 patients. The complete clinical, virological and immunological responses were associated with PEG-IFN plus RIBA. Severe infections were associated with renal failure. At 10 years, the overall survival rate was 71% in Type II MC and 84% in Type III (p < 0.053). CONCLUSIONS: From our data, antiviral therapy is the first-line therapy in HCV-related MC, whereas steroids, alkylating agents and Rituximab should be considered as a second-line therapy. Given the heterogeneity of the disease, the role of these different therapeutic strategies should be checked in randomized controlled trials.

Long-term effects of the new direct antiviral agents (DAAs) therapy for HCV-related mixed cryoglobulinaemia without renal involvement: a multicentre open-label study.

OBJECTIVES: To investigate the long-term effects and safety of new direct anti-viral agents (DAAs) in patients with hepatitis C virus (HCV)-related mixed cryoglobulinaemia (MC) without renal involvement. METHODS: The study enrolled 22 consecutive patients, 19 received sofosbuvir-based regimen and three patients received other DAAs, individually tailored according to latest guidelines. As of December 2016, the median length of follow-up was 17 months (range 13-21). RESULTS: Extra-hepatic manifestations at enrollment were: purpura and arthralgia (12 cases), peripheral neuropathy (10 cases) and marginal zone B- lymphomas (2 cases). After a four-week DAA therapy, all patients became HCV- negative. Moreover, after 48 weeks since the beginning of DAA treatment, sustained regression of purpura and arthralgias was observed respectively in eight and in nine cases; peripheral neuropathy improved in seven cases, and cryocrit median values decreased from three (1-20) at baseline to two (1-12) after 48 weeks. Two cases with indolent marginal zone lymphomas did not show any haematological response: size and number of the involved nodes remained unchanged. In addition, the monoclonal B-cell population found in the peripheral blood in four cases did not disappear after recovery from HCV- RNA. Mild side effects occurred in nine patients, but six patients developed ribavirin-related anaemia requiring reduction of ribavirin dose. CONCLUSIONS: DAA therapy is safe and effective to eradicate HCV in MC, but seems associated with satisfactory clinical response in mild or moderate cryoglobulinaemic vasculitis and no response in B-NHL.

Hepatitis C Virus-Associated Non-Hodgkin Lymphomas: Biology, Epidemiology, and Treatment.

Eradication of hepatitis C virus (HCV) in indolent non-Hodgkin lymphomas (NHLs), especially in marginal zone lymphomas, determines the regression of the hematologic disorder in a significant fraction of cases. Because direct antiviral agents show an excellent profile in terms of efficacy, safety, and rapid onset of action, these drugs can be used in any clinical situation and in the presence of any comorbidities. To avoid the progression of the NHL, despite HCV eradication, antiviral therapy should be provided as soon as the viral infection is discovered; before that, the chronic antigenic stimulation determines the irreversible proliferation of neoplastic B cells.

HCV-unrelated cryoglobulinaemic vasculitis: the results of a prospective observational study by the Italian Group for the Study of Cryoglobulinaemias (GISC).

OBJECTIVES: To investigate the clinical and laboratory patterns of HCV-unrelated cryoglobulinaemic vasculitis (CV), and the factors influencing its outcome. METHODS: Prospective study of all anti-HCV and HCV-RNA negative patients with CV who have been observed since January 2004 in 17 centres participating in the Italian Group for the Study of Cryoglobulinaemias (GISC). RESULTS: 175 enrolled were followed up for 677 person-years. The associated conditions were primary Sjögren's syndrome (21.1%), SLE (10.9%), other autoimmune disorders (10.9%), lymphoproliferative diseases (6.8%), solid tumours (2.3%) and HBsAg positivity (8.6%), whereas 69 patients (39.4%) had essential CV. There were significant differences in age (p<0.001), gender (p=0.002), the presence of purpura (p=0.005), arthralgia (p=0.009), liver abnormalities (p<0.001), sicca syndrome (p<0.001), lymphadenopathy (p=0.003), splenomegaly (p=0.002), and rheumatoid factor titres (p<0.001) among these groups. Type II mixed cryoglobulins were present in 96 cases (54.9%) and were independently associated with purpura and fatigue (odds ratio [OR]4.3; 95% confidence interval [CI] 1.8-10.2; p=0.001; and OR2.8; 95%CI 1.3-6.3; p=0.012). Thirty-one patients died during follow-up, a mortality rate of 46/1000 person-years. Older age (for each additional year, adjusted hazard ratio [aHR] 1.13; 95%CI 1.06-1.20; p<0.001), male gender (aHR 3.45; 95%CI 1.27-9.40; p=0.015), type II MCG (aHR 3.31; 95%CI 0.09-1.38; p=0.047) and HBsAg positivity (aHR 7.84; 95%CI 1.20-36.04; p=0.008) were independently associated with greater mortality. CONCLUSIONS: HCV-unrelated CV is a multifaceted and often disabling disorder. The associated conditions influence its clinical severity, giving rise to significantly different clinical and laboratory profiles and outcomes.