{Reference Type}: Journal Article
{Title}: Serum proteomics reveals hemophagocytic lymphohistiocytosis-like phenotype in a subset of patients with multisystem inflammatory syndrome in children.
{Author}: Tulling AJ;Holierhoek MG;Jansen-Hoogendijk AM;Hoste L;Haerynck F;Tavernier SJ;Oostenbrink R;Buysse CMP;Bannier MAGE;Bekhof J;Breukels M;Hammer SC;Jacobs MAM;Kamps AWA;van der Linden JW;Lebon A;Oudshoorn JH;Tramper-Stranders GA;Vastert SJ;Wieringa JW;Terheggen-Lagro SWJ;Wildenbeest JG;von Asmuth EGJ;van den Akker EB;van Gijn ME;Lugthart G;Buddingh EP;
{Journal}: Clin Immunol
{Volume}: 264
{Issue}: 0
{Year}: 2024 Jul 12
{Factor}: 10.19
{DOI}: 10.1016/j.clim.2024.110252
{Abstract}: Children with Multisystem Inflammatory Syndrome in Children (MIS-C) can present with thrombocytopenia, which is a key feature of hemophagocytic lymphohistiocytosis (HLH). We hypothesized that thrombocytopenic MIS-C patients have more features of HLH. Clinical characteristics and routine laboratory parameters were collected from 228 MIS-C patients, of whom 85 (37%) were thrombocytopenic. Thrombocytopenic patients had increased ferritin levels; reduced leukocyte subsets; and elevated levels of ASAT and ALAT. Soluble IL-2RA was higher in thrombocytopenic children than in non-thrombocytopenic children. T-cell activation, TNF-alpha and IFN-gamma signaling markers were inversely correlated with thrombocyte levels, consistent with a more pronounced cytokine storm syndrome. Thrombocytopenia was not associated with severity of MIS-C and no pathogenic variants were identified in HLH-related genes. This suggests that thrombocytopenia in MIS-C is not a feature of a more severe disease phenotype, but the consequence of a distinct hyperinflammatory immunopathological process in a subset of children.