Inflammasome pathways

Inflammasomes are cytosolic multiprotein complexes. They are an important component of the innate immune system, and their activation is a process for inflammation. Their pathologies cause for many autoinflammatory diseases such as familial Mediterranean fever (FMF), cryopyrin associated periodic fever syndrome (CAPS), and autoimmune disorders. The NLRP3 inflammasome is the most famous one. Inflammasome activation pathways are canonical, non-canonical, and alternative. There is a two-step model in which signal 1 is for priming and signal 2 is for activation. Inflammasome formation is triggered by sensors of danger or damage associated molecular patterns (DAMPs) or pathogen-associated molecular patterns (PAMPs). In response to these stimuli, the caspase-1 enzyme is activated. And it converts the proactive form of interleukin (IL)-1 beta to active IL-1beta and the same procedure for IL-18 which are pro-inflammatory cytokines. According to recent studies, COVID-19 infection also has the potential to activate inflammasomes to induce hyperinflammation which may be related to disease severity. © 2023 Nova Science Publishers, Inc. All rights reserved.

MIS-C: A COVID-19-as sociated condition between hypoimmunity and hyperimmunity.

Multisystem inflammatory syndrome in children (MIS-C) is a rare, severe complication of COVID-19. A better knowledge of immunological, cellular, and genetic characteristics of MIS-C could help better understand the pathogenesis of the disease and contribute to identifying specific diagnostic biomarkers and develop targeted therapies. We studied 37 MIS-C children at hospital admission and 24 healthy controls analyzing serum cytokines (IFN-α, IFN-ß, IFN-γ, IL-6, IL-10, IL-17A, IL-12p70 and TNF), lymphocyte populations by flow cytometry and 386 genes related to autoimmune diseases, autoinflammation and primary immunodeficiencies by NGS. MIS-C patients showed a significant increase of serum IFNγ (despite a significant reduction of activated Th1) and ILs, even if with a great heterogeneity among patients, revealing different pathways involved in MIS-C pathogenesis and suggesting that serum cytokines at admission may help to select the inflammatory pathways to target in each patient. Flow cytometry demonstrated a relevant reduction of T populations while the percentage of B cell was increased in agreement with an autoimmune pathogenesis of MIS-C. Genetic analysis identified variants in 34 genes and 83.3% of patients had at least one gene variant. Among these, 9 were mutated in more patients. Most genes are related to autoimmune diseases like ATM, NCF1, MCM4, FCN3, and DOCK8 or to autoinflammatory diseases associated to the release of IFNγ like PRF1, NOD2, and MEF. Thus, an incomplete clearance of the Sars-CoV2 during the acute phase may induce tissue damage and self-antigen exposure and genetic variants can predispose to hyper-reactive immune dysregulation events of MIS-C-syndrome. Type II IFN activation and cytokine responses (mainly IL-6 and IL-10) may cause a cytokine storm in some patients with a more severe acute phase of the disease, lymphopenia and multisystemic organ involvement. The timely identification of such patients with an immunocytometric panel might be critical for targeted therapeutic management.

Anakinra in Paediatric Rheumatology and Periodic Fever Clinics: Is the Higher Dose Safe?

Objective: Anakinra has been increasingly used in off-label indications as well as dosing and mode of administration in a variety of inflammatory conditions. We aimed to review our clinical practice and compare treatment outcomes with published data. Methods: Clinical data from electronic records were retrospectively reviewed for patients treated with anakinra over the past 6 years for autoinflammatory diseases (AID). Results: From 47 eligible patients (27 female patients), 32 were children. Macrophage activation syndrome (MAS) was the indication for anakinra therapy in 42.6% of patients. Systemic juvenile idiopathic arthritis (SJIA) was the most common underlying diagnosis (19/47) followed by the spectrum of AID. Off-label use was noted in 38.3% patients. Recommended dose was exceeded in 21 children (mean induction dose 5.1, highest dose 29.4 mg/kg/day) and two adults; five patients were treated intravenously. The mean treatment duration for SJIA was 1.4 years, that for AID was 2.2 years, and that for patients with higher anakinra dose was 9.7 (19.3) months. The mean follow-up duration was 2.7 (1.7) years. Treatment was effective in the majority of SJIA and cryopyrinopathy patients as well as those with MAS. Anakinra was well-tolerated without any major adverse effects even in patients with long-term administration of higher than recommended doses including two infants treated with a dose of over 20 mg/kg/day. Conclusion: Our results support early use of anakinra in the individually tailored dosing. In patients with hyperinflammation, anakinra may be lifesaving and may even allow for corticosteroid avoidance. Further studies are needed in order to set up generally accepted response parameters and define condition-specific optimal dosing regimen.

Clinical characteristics and COVID-19 outcomes in a regional cohort of pediatric patients with rheumatic diseases.

BACKGROUND: This study aimed to assess the baseline characteristics and clinical outcomes of coronavirus disease 2019 (COVID-19) in pediatric patients with rheumatic and musculoskeletal diseases (RMD) and identify the risk factors associated with symptomatic or severe disease defined as hospital admission, intensive care admission or death. METHODS: An observational longitudinal study was conducted during the first year of the SARS-CoV-2 pandemic (March 2020-March 2021). All pediatric patients attended at the rheumatology outpatient clinics of six tertiary referral hospitals in Madrid, Spain, with a diagnosis of RMD and COVID-19 were included. Main outcomes were symptomatic disease and hospital admission. The covariates were sociodemographic and clinical characteristics and treatment regimens. We ran a multivariable logistic regression model to assess associated factors for outcomes. RESULTS: The study population included 77 pediatric patients. Mean age was 11.88 (4.04) years Of these, 30 patients (38.96%) were asymptomatic, 41 (53.25%) had a mild-moderate COVID-19 and 6 patients (7.79%) required hospital admission. The median length of hospital admission was 5 (2-20) days, one patient required intensive care and there were no deaths. Previous comorbidities increased the risk for symptomatic disease and hospital admission. Compared with outpatients, the factor independently associated with hospital admission was previous use of glucocorticoids (OR 3.51; p = 0.00). No statistically significant risk factors for symptomatic COVID-19 were found in the final model. CONCLUSION: No differences in COVID-19 outcomes according to childhood-onset rheumatic disease types were found. Results suggest that associated comorbidities and treatment with glucocorticoids increase the risk of hospital admission.

COVID-19 Pandemic and Patients with Rare Inherited Metabolic Disorders and Rare Autoinflammatory Diseases-Organizational Challenges from the Point of View of Healthcare Providers.

COVID-19 pandemic is an organisational challenge for both healthcare providers and patients. People with rare inherited metabolic disorders (IMD) and rare autoinflammatory diseases (AD) are vulnerable patients whose well-being is deeply connected with regular follow-ups. This study aimed to assess how e one year of coronavirus pandemic has impacted the treatment of patients with IMD and AD in Poland. Surveys were distributed to all healthcare providers that coordinate the treatment of IMD and AD patients. Thirty-two responders (55%) answered the survey. They provide care to 1726 patients with IMD/AD, including 246 patients on dedicated treatment. In 35% of units, the regular appointments were disrupted, primarily because of patient infection. In 18 hospitals, remote visits were implemented, but only 66.6% of patients used this form of consultation. In 14/32 hospitals, administration of the therapy was delayed (median: 17.4 days). Forty-four patients suffered from SARS-COV-2 infection, in majority with mild symptoms. However, four adult patients developed complications, and one died following a SARS-COV-2 infection. Although most hospitals managed to maintain regular visits during the pandemic, more comprehensive implementation of telemedicine and switch to oral therapy or home infusions would be a reasonable solution for the current epidemic situation.

COVID-19 and autoinflammatory diseases: prevalence and outcomes of infection and early experience of vaccination in patients on biologics.

OBJECTIVES: The systemic autoinflammatory diseases are rare conditions; to date, data on coronavirus disease 2019 (COVID-19) infection and vaccination safety are scarce. Agents targeting innate immune pathways have transformed the management of affected patients, and their outcomes are of wider interest given the role of inflammation in both viral clearance and severe COVID-19 disease. We surveyed patients with systemic autoinflammatory disease on biologic therapy to determine the prevalence and outcomes of COVID-19 infection and to gather early safety data on vaccination. METHODS: Electronic medical records of 248 patients with systemic autoinflammatory disease on biologic therapy at a national centre were reviewed. Patients were then surveyed in clinic or using a Web-based survey. RESULTS: In the cohort of 248 patients, no deaths were recorded. One hundred and seventy-five survey responses were received. Among the respondents, 27 reported suspected COVID-19 infection, of which 14 were confirmed by testing (8.0%). Two patients required hospital admission owing to dehydration. No patient required respiratory support or intensive care. One hundred and thirty-eight doses of COVID-19 vaccine had been administered to 130 patients. Side effects were reported after 71 of 138 (51.4%) administrations and were consistent with a flare of the underlying disease in 26 of 138 (18.8%) instances. No serious adverse events or hospital admissions were reported after vaccination. CONCLUSION: These data, including the largest published series of patients on anti-IL-1/6 biologics to receive any adenoviral vector or messenger RNA vaccine, show no serious early concerns regarding vaccination and will provide an urgently needed resource to inform decision-making of these patients and their clinicians.

COVID-19 in Autoinflammatory Diseases with Immunosuppressive Treatment.

COVID-19 disease increases interleukin (IL)-1ß release. Anti-IL-1-treatment is effective in IL-1-mediated autoinflammatory diseases (AID). This case series presents COVID-19 in patients with IL-1-mediated and unclassified AID with immunosuppressive therapy (IT). Patient 1 is a 34-year-old woman with an unclassified AID and methotrexate. Patients 2 and 3 (14-year-old girl and 12-year-old boy, respectively) have a Cryopyrin-Associated Periodic Syndrome (NLRP3 p.Q703K heterozygous, CAPS) treated with canakinumab 150 mg/month since three and five years, respectively. Patient 4 is a 15-year-old girl who has had familial Mediterranean fever (MEFV p.M694V homozygous) for 3 years treated with canakinumab 150 mg/month and colchicine. All patients had a mild acute COVID-19 course, particularly the adolescent patients. A few weeks after COVID-19 recovery, both CAPS patients developed increased AID activity, necessitating anti-IL-1-treatment intensification in one patient. At day 100, one out of four patients (25%) showed positive antibody response to SARS-CoV-2. This is one of the first reports providing follow-up data about COVID-19 in AID. The risk for severe acute COVID-19 disease was mild/moderate, but increased AID activity post-COVID-19 was detected. Follow-up data and data combination are needed to expand understanding of COVID-19 and SARS-CoV-2 immunity in AID and the role of IT.

Management of childhood-onset autoinflammatory diseases during the COVID-19 pandemic.

Concerns regarding the comorbidity as a significant risk factor for Coronavirus Disease-2019 (COVID-19), gave rise to an urgent need for studies evaluating patients with chronic conditions such as autoinflammatory diseases (AIDs). We prepared a web-based survey investigating the clinical findings and contact histories among pediatric patients with AIDs. Confirmed COVID-19 cases, patients with contact history and those with symptoms which were highly suggestive of COVID-19 were called via phone or recruited to a video or face to face appointment. Data of AIDs were obtained from their medical records, retrospectively. Laboratory and screening findings were confirmed by our national health registry website. There were 404 patients (217 female) eligible for the enrollment. During pandemic, 375 (93%) were on colchicine treatment and 48 (11.8%) were receiving biologic treatment. Twenty-four out of 404 patients were admitted to hospital due to COVID-19 suspicion. Severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) was identified through rhinopharyngeal swabs in seven patients, six of whom were only on colchicine treatment. Only one patient with no finding of any severe respiratory complications was hospitalized. All of seven patients recovered completely. Among patients on biologic drugs, neither a symptom nor a positive polymerase chain reaction test for COVID 19 was detected. In conclusion, pediatric patients with AIDs, those receiving biologic treatment and/or colchicine, may not be at increased risk for neither being infected nor the severe disease course.