Care of patients with inborn errors of immunity in thirty J Project countries between 2004 and 2021

Introduction

The J Project (JP) physician education and clinical research collaboration program was started in 2004 and includes by now 32 countries mostly in Eastern and Central Europe (ECE). Until the end of 2021, 344 inborn errors of immunity (IEI)-focused meetings were organized by the JP to raise awareness and facilitate the diagnosis and treatment of patients with IEI.

Results

In this study, meeting profiles and major diagnostic and treatment parameters were studied. JP center leaders reported patients' data from 30 countries representing a total population of 506 567 565. Two countries reported patients from JP centers (Konya, Turkey and Cairo University, Egypt). Diagnostic criteria were based on the 2020 update of classification by the IUIS Expert Committee on IEI. The number of JP meetings increased from 6 per year in 2004 and 2005 to 44 and 63 in 2020 and 2021, respectively. The cumulative number of meetings per country varied from 1 to 59 in various countries reflecting partly but not entirely the population of the respective countries. Altogether, 24,879 patients were reported giving an average prevalence of 4.9. Most of the patients had predominantly antibody deficiency (46,32%) followed by patients with combined immunodeficiencies (14.3%). The percentages of patients with bone marrow failure and phenocopies of IEI were less than 1 each. The number of patients was remarkably higher that those reported to the ESID Registry in 13 countries. Immunoglobulin (IgG) substitution was provided to 7,572 patients (5,693 intravenously) and 1,480 patients received hematopoietic stem cell therapy (HSCT). Searching for basic diagnostic parameters revealed the availability of immunochemistry and flow cytometry in 27 and 28 countries, respectively, and targeted gene sequencing and new generation sequencing was available in 21 and 18 countries. The number of IEI centers and experts in the field were 260 and 690, respectively. We found high correlation between the number of IEI centers and patients treated with intravenous IgG (IVIG) (correlation coefficient, cc, 0,916) and with those who were treated with HSCT (cc, 0,905). Similar correlation was found when the number of experts was compared with those treated with HSCT. However, the number of patients treated with subcutaneous Ig (SCIG) only slightly correlated with the number of experts (cc, 0,489) and no correlation was found between the number of centers and patients on SCIG (cc, 0,174).

Conclusions

1) this is the first study describing major diagnostic and treatment parameters of IEI care in countries of the JP; 2) the data suggest that the JP had tremendous impact on the development of IEI care in ECE; 3) our data help to define major future targets of JP activity in various countries; 4) we suggest that the number of IEI centers and IEI experts closely correlate to the most important treatment parameters; 5) we propose that specialist education among medical professionals plays pivotal role in increasing levels of diagnostics and adequate care of this vulnerable and still highly neglected patient population; 6) this study also provides the basis for further analysis of more specific aspects of IEI care including genetic diagnostics, disease specific prevalence, newborn screening and professional collaboration in JP countries.

OP0219 HIGH INCIDENCE OF MIS-C AND OTHER AUTOIMMUNE DISEASES AFTER SARS-COV-2 INFECTION COMPARED TO COVID-19 VACCINATION IN PEDIATRIC POPULATION FROM SOUTH CENTRAL EUROPE

Background

In contrast to adults, children are less likely to develop serious disease upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) but are at increased risk for inflammatory and autoimmune diseases linked to the virus (1). The reported incidence of multisystem inflammatory syndrome in children (MIS-C) varied from 0.2 to 11.4/100,000 persons under 21 years (2,3). It is yet unknown whether MIS-C can recur after SARS-CoV-2 reinfection or COVID-19 vaccination.

Objectives

To estimate the incidence and describe the spectrum of inflammatory and autoimmune diseases linked to SARS-CoV-2 infection and coronavirus (COVID-19) vaccination in pediatric patients from two neighbouring South Central European countries and regions, Slovenia and Friuli Venezia Giulia (FVG), Italy.

Methods

We performed a multi-centre prospective cohort study of all children and adolescents (under 18 years) newly diagnosed with MIS-C or other inflammatory/autoimmune diseases linked to SARS-CoV-2 infection, who were admitted to the pediatric tertiary care hospitals in Slovenia or FVG, Italy during the period from January 1, 2020, to December 31, 2021. These hospitals serve a combined population of 587,053 children and adolescents. Only patients who had positive anti-SARS-CoV-2 antibodies and/or positive SARS-CoV-2 PCR test within 3 months prior to disease onset were considered for estimating the disease incidence. We obtained the number of patients with serious adverse events (SAE) after COVID-19 vaccination and the number of patients with severe COVID-19 in the same population. This study was conducted as a part of the EU interregional Italy-Slovenia project CATTEDRA (Cross border cooperation for innovative diagnosis of rare diseases in paediatrics).

Results

192 children and adolescents were diagnosed with inflammatory and autoimmune diseases linked to SARS-CoV-2 (Figure 1). Median age at diagnosis was 11.9 years (IQR 7.6 -14.7). All included patients were White. Incidence of MIS-C was one in 921 children and adolescents after SARS-CoV-2 infection and one in 5870 of all children and adolescents. Cumulative incidence of MIS-C since the start of the pandemic was 17/100,000 children and adolescents. Until December 31, 2021, 92,139 children and adolescents (15.7 %) received at least one dose of COVID-19 vaccine. Three patients presented with inflammatory/autoimmune disease after COVID-19 vaccination, including 2 patients with MIS-C and one patient with myositis. All 3 had evidence of recent SARS-CoV-2 infection in form of positive anti-N SARS-CoV-2 antibodies. In the same period, 15 children and adolescents were hospitalised with severe COVID-19. Seven patients from our cohort were vaccinated against COVID-19 median 8 months after MIS-C and further 6 patients had a SARS-CoV-2 reinfection 3-14 months after MIS-C. None of them experienced SAE or recurrence of MIS-C.

Figure 1.

Inflammatory and autoimmune diseases linked to SARS-CoV-2 and severe COVID-19 in pediatric population in Slovenia and FVG, Italy

COVID-19=coronavirus disease, FVG=Friuli Venezia Giulia region in Italy, MIS-C=multisystem inflammatory syndrome in children, SARS-CoV-2=severe acute respiratory syndrome coronavirus 2

Conclusion

MIS-C was the most common manifestation and its incidence in this predominantly white population was higher than previously reported. Based on our limited experience, MIS-C does not seem to recur after SARS-CoV-2 reinfection or COVID-19 vaccination, however long-term data are lacking. Autoimmune diseases were much more common after SARS-CoV-2 infection than after COVID-19 vaccination. Hospitalisations due to MIS-C were seven times as frequent as hospitalisations due to severe COVID-19 in children.

References

[1]Ramaswamy A, et al. Immunity. 2021;54:1083-1095.e7.

[2]Belay ED, et al. JAMA Pediatrics. 2021;175:837–45.

[3]Lee EH, et al. JAMA Netw Open. 2020;3:e2030280.

Disclosure of Interests

None declared

Wiskott Aldrich syndrome protein regulates non-selective autophagy and mitochondrial homeostasis in human myeloid cells

The actin cytoskeletal regulator Wiskott Aldrich syndrome protein (WASp) has been implicated in maintenance of the autophagy-inflammasome axis in innate murine immune cells. Here, we show that WASp deficiency is associated with impaired rapamycin-induced autophagosome formation and trafficking to lysosomes in primary human monocyte-derived macrophages (MDMs). WASp reconstitution in vitro and in WAS patients following clinical gene therapy restores autophagic flux and is dependent on the actin-related protein complex ARP2/3. Induction of mitochondrial damage with CCCP, as a model of selective autophagy, also reveals a novel ARP2/3-dependent role for WASp in formation of sequestrating actin cages and maintenance of mitochondrial network integrity. Furthermore, mitochondrial respiration is suppressed in WAS patient MDMs and unable to achieve normal maximal activity when stressed, indicating profound intrinsic metabolic dysfunction. Taken together, we provide evidence of new and important roles of human WASp in autophagic processes and immunometabolic regulation, which may mechanistically contribute to the complex WAS immunophenotype.

Recurrent Fulminant Myocarditis Repeatedly Treated with Ecmo in a Child

Recurrent myocarditis is rare with only few reports having been published for paediatric cases. Repeated use of extracorporeal membrane oxygenation is also uncommon. In this paper we will present a very rare case of a 7-year old girl with recurrent fulminant myocarditis with heart failure requiring cardiopulmonary resuscitation and mechanical circulatory support with extracorporeal membrane oxygenation. Both episodes were precipitated by a viral upper respiratory tract infection, and in both cases the cardiac function eventually completely recovered. The second episode of fulminant myocarditis was particularly complex with markedly elevated markers of myocardiocytolysis, multiorgan dysfunction and the need for prolonged mechanical circulatory support. Nevertheless, the patient made a remarkable recovery. A comprehensive diagnostic workup pointed towards an aberrant immune response as the likely cause of the girl's susceptibility for fulminant myocarditis.

Clinical and immunological manifestations of patients with atypical severe combined immunodeficiency

Hypomorphic mutations in genes associated with severe combined immunodeficiency (SCID) or Omenn syndrome can also cause milder immunodeficiencies. We report 10 new patients with such "atypical" SCID and summarize 63 patients from the literature. The patient groups with T(low)B(low) (n=28), T(low)B(+) (n=16) and ADA (n=29) SCID variants had similar infection profiles but differed in the frequency of immune dysregulation, which was observed predominantly in patients with recombination defects. Most immunological parameters were remarkably similar in the three groups. Of note, 19/68 patients with "atypical" SCID had normal T cell counts, 48/68 had normal IgG and 23/46 had at least one normal specific antibody titer. Elevated IgE was a characteristic feature of ADA deficiency. This overview characterizes "atypical" SCID as a distinct disease with immune dysregulation in addition to infection susceptibility. Lymphopenia, reduced naïve T cells and elevated IgE are suggestive, but not consistent features of the disease.

Estimation of antiphospholipid antibodies in a prospective longitudinal study of children with migraine

The aim of this study was to determine the prevalence and clinical significance of antiphospholipid antibodies (aPL) in children with migraine. The values of anticardiolipin (aCL) and antibeta2 glycoprotein I (antibeta2GPI) antibodies were assayed by an ELISA method in 52 children with migraine and 22 children with tension-type headache. The control group consisted of 61 apparently healthy children at regular preventive visits. Two monoclonal beta2GPI dependent aCL (HCAL and EY2C9) were used as calibrators. Lupus anticoagulant (LA) was determined by a modified dilute Russell viper venom time test. Persistently positive aPL were observed during the follow-up in 16.3% of children with migraine (9.3% for aCL, 7.0% for antibeta2GPI and 0% for LA) and in 16.7% of children with tension-type headache (11.1% for aCL, 5.6% for antibeta2GPI and 0% for LA). The prevalence of aPL did not differ significantly between patient groups and healthy children. The prevalence of aPL does not appear to be increased in an unselected group of children with migraine, however, the possible role of aPL in individual cases of paediatric migraine can not be excluded.