Activin a suppresses peripheral CD8+ T lymphocyte activity in acute-phase Kawasaki disease

Efficacy and safety of infliximab in the treatment of Kawasaki disease: A systematic review and meta-analysis

Infliximab is a monoclonal antibody specifically binding tumor necrosis factor-alpha and has been approved for the treatment of several inflammatory disorders. However, the efficacy of infliximab in primary treatment of Kawasaki disease (KD) or retreatment of intravenous immunoglobulin (IVIG)-resistant KD in children is controversial. Therefore, we conducted a meta-analysis to compare the efficacy of infliximab alone or in combination with IVIG to IVIG. Eligible randomized and non-randomized trials were retrieved by searching literature databases prior to May 31, 2023. Pooled odds ratio (OR) and 95% confidence interval (95% CI) were calculated for dichotomous variables, and mean difference (MD) with 95% CI was estimated for continuous variables. A total of 14 eligible studies comprising 1257 participants were included. In refractory KD, infliximab alone was associated with a higher effectiveness rate (OR = 4.48, 95% CI 2.67-7.52) and defervescence rate (OR = 5.01, 95% CI 2.99-8.37) and resulted in a 1.08-day-shorter duration of fever (95% CI 0.61-1.55, P < 0.001) and 1.36-day-shorter length of hospital stay (95% CI 0.65-2.08) compared with IVIG. Incidences of coronary artery lesions (CALs), newly developing CALs, and CAL regression did not differ between both groups. For initial treatment of KD, infliximab in addition to IVIG led to a nominally significant higher effectiveness rate (OR = 2.26, 95% CI 1.02-5.01) and a larger reduction of right coronary artery Z score (MD = -0.24, 95% CI -0.27 to -0.21) but did not show additional efficacy in improving other outcomes. The safety profile was similar between both groups.   Conclusion: The meta-analysis demonstrates that infliximab alone is a well-tolerated and effective treatment for IVIG-resistant KD. The additional efficacy of infliximab to IVIG for initial treatment of KD is limited. More large and high-quality trials are needed to confirm the efficacy of infliximab, especially for intensification of primary treatment for KD. What is Known: • Infliximab is a novel monoclonal antibody specifically blocking tumor necrosis factor-alpha and is approved for treatment of several immune-mediated inflammatory disorders. • The efficacy of infliximab in treating children with Kawasaki disease is controversial. What is New: • Infliximab is an effective and safe treatment for children with refractory Kawasaki disease but adds limited efficacy to intravenous immunoglobulin for initial treatment of Kawasaki disease.

Immunophenotyping of peripheral blood cells allows to discriminate MIS-C and Kawasaki disease

BACKGROUND

The pathogenesis of the novel described multisystem inflammatory syndrome in children (MIS-C) and Kawasaki disease (KD) is still debated as it is not clear if they are the same or different nosological entities. However, for both the diseases a rapid and unequivocal diagnosis is mandatory to start the therapy before the onset of severe complications. In this study, we aimed to evaluate the white cell populations in MIS-C and KD as potential markers to discriminate between the two diseases.

METHODS

We studied white cell populations by flow cytometry in 46 MIS-C and 28 KD patients in comparison to 70 age-matched healthy children.

RESULTS

MIS-C patients had a significant lymphopenia that involved both B and T populations while KD patients showed a significant neutrophilia and thrombocythemia. Granulocyte/lymphocyte ratio helped to diagnose both MIS-C and KD with a high diagnostic sensitivity, while a multivariate analysis of granulocyte and T lymphocyte number contributed to discriminate between the two diseases.

CONCLUSIONS

The relevant lymphopenia observed in MIS-C patients suggests that the disease would be a post-infectious sequel of COVID-19 immunologically amplified by a massive cytokine release, while the significant neutrophilia and thrombocythemia observed in KD confirmed that the disorder has the genesis of a systemic vasculitis. The analysis of a panel of circulating cells may help to early diagnose and to discriminate between the two diseases.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1186/s41231-022-00128-2.

Different Immunoregulation Roles of Activin A Compared With TGF-β

Activin A, a critical member of the transforming growth factor-β (TGF-β) superfamily, is a pluripotent factor involved in allergies, autoimmune diseases, cancers and other diseases with immune disorder. Similar to its family member, TGF-β, activin A also transmits signals through SMAD2/SMAD3, however, they bind to distinct receptors. Recent studies have uncovered that activin A plays a pivotal role in both innate and adaptive immune systems. Here we mainly focus its effects on activation, differentiation, proliferation and function of cells which are indispensable in the immune system and meanwhile make some comparisons with those of TGF-β.