ABSTRACT
Cryoglobulinaemia consists of circulating monoclonal and/or polyclonal immunoglobulins with rheumatoid factor (RF) activity that precipitate at temperatures <37°C. Cryoglobulinaemic syndrome, characterised by clinical signs of systemic vasculitis, is associated with chronic infection of hepatitis C virus (HCV) and might evolve in B-cell malignancies. In about one third of all HCV infection cases, serum autoantibodies are commonly found. This is probably due directly to the transformation of infected B cells but, also, indirectly, to the viral chronic stimulation of a pool of autoreactive B cells. The pattern of IgG subclasses seems to contribute to the worsening progression of HCV infection into lymphoproliferative and/or autoimmune diseases. Many evidences showed that B cells circulating in patients with HCV-associated mixed cryoglobulinaemia (MC) are profoundly abnormal;moreover, in most of cases, normal B cells are replaced by expanded clonal B cells characterised by the low expression of CD21. After viral eradication, these cells persist in circulation and their occurrence does not correlate with serum cryoglobulins nor with vasculitis response or relapse. It is probably due to the persistence of monoclonal B cells producing RF, that in course of MC can be reactivated by circulating immune complexes, highly produced during infections or tumours. Here, we aimed to review current literature focusing the pathogenesis of MC referring to specificity and immunochemical characteristics of the immunoglobulins involved in cryoprecipitation.
Subject(s)
COVID-19 , Pandemics , Child , Humans , Pandemics/prevention & control , Patient-Centered CareABSTRACT
OBJECTIVE: Since the start of the COVID-19 pandemic, millions of people have been infected with thousands of deaths. Few data regarding factors that increase the risk of infection are available. Our study aimed to evaluate all people living in retirement homes (PLRNH) and identify factors that could increase infection risk in a close community. MATERIALS AND METHODS: We conducted a retrospective study enrolling all PLRNH, where at least one SARS-CoV-2 infected person was present. Variables were compared with Student's t-test or Pearson chi-square test as appropriate. Uni- and multivariate analyses were conducted to evaluate variables' influence on the infection. RESULTS: We included 452 PLRNH; 144 (31.7%) were male, with a mean age of 82.2±8.6 years. People with a positive swab for SARS-CoV-2 were 306 (67.4%). A significant difference between SARS-CoV-2 infected and not infected was observed in the percentage of those receiving chronic treatment with Angiotensin II receptor blockers (ARBs) (18.6% vs. 9.5%, p=0.012). On the contrary, there was no difference in the proportion of those receiving ACE inhibitors (ACE-I) (21.2% vs. 23.6%, p=0.562). At multivariate analysis, people with mental illness and cancer had an increased risk of being infected. Furthermore, receiving ARBs as a chronic treatment was an independent predictor of infection risk [OR 1.95 (95% CI 1.03-3.72) p=0.041]. CONCLUSIONS: Our data suggest that, in close communities, such as retirement nursing homes, the receipt of ARBs increased the risk of acquiring SARS-CoV-2 infection. However, before changing an important chronic treatment in a fragile population, such as the elderly living in retirement nursing homes, clinicians should carefully evaluate the risk-benefit ratio.
Subject(s)
Angiotensin Receptor Antagonists/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , COVID-19/epidemiology , SARS-CoV-2 , Aged, 80 and over , Angiotensin Receptor Antagonists/administration & dosage , Angiotensin Receptor Antagonists/adverse effects , Angiotensin-Converting Enzyme Inhibitors/administration & dosage , Angiotensin-Converting Enzyme Inhibitors/adverse effects , COVID-19/transmission , Drug Utilization , Female , Homes for the Aged/statistics & numerical data , Humans , Male , Nursing Homes/statistics & numerical data , Pandemics , Retrospective Studies , Risk AssessmentABSTRACT
Since the start of the SARS-CoV-2 outbreak, more than 4 million cases have been reported with almost 300,000 deaths. Commonly, the virus involves the respiratory system causing fever, cough, and dyspnea. On the contrary, cutaneous involvement has been infrequently reported. We described the case of a 72-year-old woman without a history of dermatologic diseases with COVID-19 who developed vasculitis-like skin eruptions. Because she has not received any treatment for COVID-19, we suggest that the dermatologic clinical picture was related to SARS-CoV-2. © Wolters Kluwer Health, Inc. All rights reserved.