Autoantibodies Detected in MIS-C Patients due to Administration of Intravenous Immunoglobulin

The autoantibody profile associated with known autoimmune diseases in patients with COVID-19 or multisystem inflammatory syndrome in children (MIS-C) remains poorly defined. Here we show that adults with COVID-19 had a moderate prevalence of autoantibodies against the lung antigen KCNRG, and SLE-associated Smith autoantigen. Children with COVID-19 rarely had autoantibodies; one of 59 children had GAD65 autoantibodies associated with acute insulin-dependent diabetes. While autoantibodies associated with SLE/Sjogren syndrome (Ro52, Ro60, and La) and/or autoimmune gastritis (gastric ATPase) were detected in 74% (40/54) of MIS-C patients, further analysis of these patients and of children with Kawasaki disease (KD), showed that the administration of intravenous immunoglobulin (IVIG) was largely responsible for detection of these autoantibodies in both groups of patients. Monitoring in vivo decay of the autoantibodies in MIS-C children showed that the IVIG-derived Ro52, Ro60, and La autoantibodies declined to undetectable levels by 45-60 days, but gastric ATPase autoantibodies declined more slowly requiring >100 days until undetectable. Together these findings demonstrate that administration of high-dose IVIG is responsible for the detection of several autoantibodies in MIS-C and KD. Further studies are needed to investigate autoantibody production in MIS-C patients, independently from IVIG administration.

High-Dose Intravenous Immunoglobulin in Severe Coronavirus Disease 2019: A Multicenter Retrospective Study in China

BackgroundThe effective treatment of coronavirus disease 2019 (COVID-19) remains unclear. We reported successful use of high-dose intravenous immunoglobulin (IVIg) in cases of severe COVID-19, but evidence from larger case series is still lacking.MethodsA multi-center retrospective study was conducted to evaluate the effectiveness of IVIg administered within two weeks of disease onset at a total dose of 2 g/kg body weight, in addition to standard care. The primary endpoint was 28-day mortality. Efficacy of high-dose IVIg was assessed by using the Cox proportional hazards regression model and the Kaplan-Meier curve adjusted by inverse probability of treatment weighting (IPTW) analysis, and IPTW after multiple imputation (MI) analysis.ResultsOverall, 26 patients who received high-dose IVIg with standard therapy and 89 patients who received standard therapy only were enrolled in this study. The IVIg group was associated with a lower 28-day mortality rate and less time to normalization of inflammatory markers including IL-6, IL-10, and ferritin compared with the control. The adjusted HR of 28-day mortality in high-dose IVIg group was 0.24 (95% CI 0.06–0.99, p<0.001) in IPTW model, and 0.27 (95% CI 0.10–0.57, p=0.031) in IPTW-MI model. In subgroup analysis, patients with no comorbidities or treated in the first week of disease were associated with more benefit from high-dose IVIg.ConclusionsHigh-dose IVIg administered in severe COVID-19 patients within 14 days of onset was linked to reduced 28-day mortality, more prominent with those having no comorbidities or treated at earlier stage.

AB0601 RAPID AND SUSTAINED EFFICACY OF AN INDUCTION TREATMENT WITH A TRIPLE THERAPY INCLUDING HIGH-DOSE INTRAVENOUS IMMUNOGLOBULINS, METHOTREXATE AND GLUCOCORTICOIDS IN ANTI-3-HYDROXY-3-METHYLGLUTARYL-COENZYME A REDUCTASE MYOPATHY

Background:Anti-3-hydroxy-3-methylglutaryl-coenzime A reductase (HMGCR) myopathy is a new entity, which has been clearly associated to statin use, even if it can be diagnosed in patients without a history of exposure to statin or even in the childhood (1).Objectives:The aim of the study is to describe the efficacy of a triple therapy regimen consisting in high-doses of intravenous immunoglobulins (IVIG), methotrexate (MTX), and glucocorticoids (GC) in 16 patients with Anti-HMGCR myopathy enrolled in 6 specialized centres.Methods:A total of 16 patients with anti-HMGCR myopathy (7 females; 9 males) were collected. Mean (±standard deviation) age at the onset of disease was 72.4±10.3 years old. All patients were diagnosed having anti-HMGCR myopathy [anti-HMGCR antibodies were measured by chemiluminescence assay (BioFlash, Inova, CA)] (2). Median follow-up was 29.5 months (interquartile range: 15.75-60 months). Anti-HMGCR antibodies were available in the follow-up in 8/16 patients.Results:Thirteen out of 16 patients (81.3%) had been exposed to statin (1/13 to red rice), 3/16 (18.7%) were not exposed. As induction therapy, 11/16 patients have been treated with triple therapy (high-dose IVIG, MTX and GC), 2/16 with double therapy (high-dose IVIG and GC), 2/16 have been treated with GC alone, the patient exposed to red rice resolved only with red rice suspension. Clinical remission and normalization of CPK values within month +24 were obtained in all the patients. All the patients were in remission at the last follow-up. Gradual improvement started soon from the first month, and among the 13 patients treated with an aggressive immunosuppresssive therapy including IVIG (13/13), GC (13/13) and methotrexate (11/13), 9/13 normalized the CPK value within 6 months. Clinical and laboratory response was accompanied by significant decrease or normalization of the anti-HMGCR antibody titer. All the patients were either not taking GC (56.3%), or were taking low doses of GC (43.7%) at the last follow-up. Four patients had stopped GC within 6 months. No serious side effects were recorded. After persistent remission, a maintenance immunosuppressive therapy was then administered. Only 3 relapses in 3 different cases were recorded, all of them during drug-free remission in long-term follow-up. Reinduction was again effective in all.Conclusion:Anti-HMGCR myopathy is a rare and serious myopathy which usually affects older people during statin treatment. After statin suspension, a rapid and sustained remission can be achieved by induction with a triple aggressive therapy consisting in medium-to high doses of GC, high-dose IVIG, and MTX (3). GC should be tapered as soon as possible. Relapse appears infrequent during maintenance treatment. Monitoring anti-HMGCR antibody titer may be clinically relevant.References:[1]AL Mammen et al. N Engl J Med. 2016;374:664-9[2]Musset L et al. Autoimmun Rev. 2016;15:983-93.[3]Aggarwal A et al. Scand J Rheumatol. 2019; 1-7.Acknowledgments:We thank MD Francesca Grosso and MD Valentina Mecheri from the University of Florence, MD Angela Zuppa and MD Chiara De Michelis, from San Martino Hospital, Genova, for their valued collaboration in data collectionDisclosure of Interests:Elena Treppo: None declared, Maria Infantino: None declared, Maurizio Benucci: None declared, Viviana Ravagnani: None declared, Boaz Palterer: None declared, Marina Grandis: None declared, Martina Fabris: None declared, Paola Tomietto: None declared, Mariangela Manfredi: None declared, Arianna Sonaglia: None declared, Maria Grazia Giudizi: None declared, Francesca Ligobbi: None declared, Daniele Cammelli: None declared, Paola Parronchi: None declared, Salvatore De Vita Consultant of: Roche, GSK, Speakers bureau: Roche, GSK, Novartis, Luca Quartuccio Consultant of: Abbvie, Bristol, Speakers bureau: Abbvie, Pfizer

High-Dose Intravenous Immunoglobulin as a Therapeutic Option for Deteriorating Patients With Coronavirus Disease 2019

The outbreak of coronavirus disease 2019 (COVID-19) has spread rapidly in China. Until now, no definite effective treatment has been identified. We reported on 3 patients with severe COVID-19 who received high-dose intravenous immunoglobulin (IVIg) with satisfactory recovery. Based on these observations, randomized studies of high-dose IVIg should be considered in deteriorating patients infected with COVID-19.

Immunological support

Until the 1980s, the use of immunoglobulin as a therapeutic agent was confined to replacement therapy in patients with primary or secondary antibody deficiency. Its role as an effective immunomodulator was discovered serendipitously, when IV immunoglobulin (IVIg) was shown to consistently increase the platelet count in a child with antibody deficiency and immune thrombocytopenic purpura. Since then, the use of high-dose IVIg as an immunomodulator has become established as an important therapeutic option in many immune-mediated diseases. This chapter reviews the therapeutic indications for immunoglobulin, and its potential adverse effects.