ABSTRACT
OBJECTIVE: Some of the manifestations of mixed cryoglobulinemia syndrome (MCS) can be severe or life-threatening, and should be rapidly contained but, as the therapeutic approaches to such conditions are largely based on anecdotal data, a consensus conference was organised by the Italian Group for the Study of Cryoglobulinemia (GISC) with the aim of providing a set of recommendations based on an in-depth survey of the available data and expert opinion. METHODS: The consensus panel, which included specialists working in different medical fields involved in the management of MCS patients, was first asked to divide the manifestations of MCS into severe or life-threatening conditions on the basis of their own experience, after which a complete literature review was carried out in accordance with the Cochrane guidelines for systematic reviews. RESULTS: Therapeutic plasma exchange (TPE) was considered the elective first-line treatment in the case of life-threatening manifestations of MCS (LT-MCS) and patients with severe clinical symptoms (S-MCS) who fail to respond to (or who are ineligible for) other treatments. The data supporting the combined use of cyclophosphamide and TPE were considered limited and inconclusive. High-dose pulsed glucocorticoid (GCS) therapy can be considered the first-line treatment of severe MCS, generally in association with TPE. Rituximab (RTX)-based treatments should be considered in patients with skin ulcers, peripheral neuropathy or glomerulonephritis, and in patients with persistent LT-MCS after TPE. In patients with hepatitis C virus-related MCS with S-MCS, viral eradication should be attempted as soon as a patient's condition allows the use of direct-acting antivirals.
Subject(s)
Cryoglobulinemia/therapy , Humans , SyndromeABSTRACT
Mixed cryoglobulinaemia syndrome (MCS) is associated with a number of infectious, autoimmune and lymphoproliferative disorders, particularly chronic hepatitis C infection. Although circulating mixed cryoglobulins (cMCGs) are a frequent finding in HCV-infected patients, only a minority of them develop a frank MCS. The only available data concerning the prevalence of MCS, which is generally considered a rare disease, come from hospital records. The aim of this investigation was to estimate the prevalence of cMCGs and MCS in a population-based study. All of the adult residents in Origgio, a town of about seven thousand inhabitants in northern Italy, were mailed a validated questionnaire, and a randomly selected sample of respondents was invited to undergo a clinical examination and laboratory tests including the determination of cMCGs. The 1594 respondents to the questionnaire (54.3% women, 64.5% aged >49years) accounted for 26.4% of the total adult population. Forty-nine (3.1%) positively responded to at least two questions, including a disproportionately high number of people aged >70years (p=0.001). Of the 266 randomly selected subjects invited to undergo a clinical examination and laboratory tests, 147 accepted, 30 (20.4%) of whom had asymptomatic type III cMCGs and four MCS. The risk of cMCG positivity was independently associated with C4 levels of <16mg/dL (adjusted odds ratio [AOR] 4.40, 95% confidence interval [CI] 1.07-18.08; p=0.040) and HCV positivity (AOR 6.87, 95% CI 1.16-40.79; p=0.034). No co-morbidities known to be related to cMCG production could be detected in more than 50% of the positive cases. After including the other positive respondents who agreed to undergo a clinical examination, the number of diagnosed MCS increased to seven: five HCV-related, one HBV-related, and one essential MCS. In conclusion, MCS seems to be more frequent than expected for a 'rare' disease, and the unexpectedly high prevalence of cMCGs raises questions about the frequency with which they are triggered, the spectrum of diseases involved in triggering them, and their real role as disease indicators.
