The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been spreading worldwide since December 2019. Hundreds of cases of children and adolescents with Kawasaki disease (KD)–like hyperinflammatory illness have been reported in Europe and the United States during the peak of the COVID-19 pandemic with or without shock and cardiac dysfunction. These patients tested positive for the polymerase chain reaction or antibody test for SARS-CoV-2 or had a history of recent exposure to COVID-19. Clinicians managing such patients coined new terms for this new illness, such as COVID-19–associated hyperinflammatory response syndrome, pediatric inflammatory multisystem syndrome temporally associated with COVID-19, or COVID-19–associated multisystem inflammatory syndrome in children (MIS-C). The pathogenesis of MIS-C is unclear; however, it appears similar to that of cytokine storm syndrome. MIS-C shows clinical features similar to KD, but differences between them exist with respect to age, sex, and racial distributions and proportions of patients with shock or cardiac dysfunction. Recommended treatments for MIS-C include intravenous immunoglobulin, corticosteroids, and inotropic or vasopressor support. For refractory patients, monoclonal antibody to interleukin-6 receptor (tocilizumab), interleukin-1 receptor antagonist (anakinra), or monoclonal antibody to tumor necrosis factor (infliximab) may be recommended. Patients with coronary aneurysms require aspirin or anticoagulant therapy. The prognosis of MIS-C seemed favorable without sequelae in most patients despite a reported mortality rate of approximately 1.5%.

Background and ObjectivesTen to twenty percent of children with Kawasaki disease (KD) do not respond to initial intravenous immunoglobulin (IVIG) treatment. If untreated, approximately 15% to 25% of KD patients have complications. The aim of this study was to find useful predictors of responsiveness to initial IVIG treatment in KD.Subjects and MethodsWe retrospectively reviewed medical records of 91 children diagnosed with KD at Myong Ji Hospital from March 2012 to April 2014. Before and after (24 hours to 36 hours) IVIG treatment, the following laboratory data were obtained: hemoglobin (Hb) level, white blood cell count, proportion of neutrophil, lymphocyte and eosinophil, platelet count, erythrocyte sedimentation rate (ERS), C-reactive protein (CRP), creatine kinase (CK), creatine kinase MB (CK-MB), and N-terminal pro-brain natriuretic peptide (NT-proBNP). Subjects were then divided into two groups: IVIG-responsive or IVIG-resistant.ResultsOf 91 patients, 11 (12%) required retreatment. By univariate analysis, before-IVIG laboratory parameters of white blood cell count, % neutrophil, ERS, CRP, sodium, CK, CK-MB, and NT-proBNP were significantly different between IVIG-responsive and IVIG-resistant patient groups. In the after-IVIG laboratory parameters, Hb level, white blood cell count, % neutrophil, % lymphocyte, CRP, CK, CK-MB, and NT-pro-BNP were significantly different between the two groups. While the mean-differences were not statistically significant, fractional change (FC)-CRP and FC-% neutrophil showed significant difference. By multivariate analysis, FC-CRP was confirmed to be an independent predictor for initial IVIG resistance.ConclusionFractional change-C-reactive protein might be a useful and important value for predicting initial IVIG resistance in KD patients.

Since mid-April 2020, cases of multisystem inflammatory syndrome in children (MIS-C) associated with coronavirus disease 2019 that mimics Kawasaki disease (KD) have been reported in Europe and North America. However, no cases have been reported in Korea. We describe an 11-year old boy with fever, abdominal pain, and diarrhea who developed hypotension requiring inotropes in intensive care unit. His blood test revealed elevated inflammatory markers, thrombocytopenia, hypoalbuminemia, and coagulopathy. Afterward, he developed signs of KD such as conjunctival injection, strawberry tongue, cracked lip, and coronary artery dilatation, and parenchymal consolidation without respiratory symptoms. Microbiological tests were all negative including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription polymerase chain reaction. However, serum immunoglobulin G against SARS-CoV-2 was positive in repeated tests using enzyme-linked immunosorbent assay and fluorescent immunoassay. He was recovered well after intravenous immunoglobulin administration and discharged without complication on hospital day 13. We report the first Korean child who met all the criteria of MIS-C with features of incomplete KD or KD shock syndrome.

The authors suggest PC(80)_Xrs5 might be a useful parameter for IOS-assessed bronchial challenge testing in preschool children with asthma.

A concerning development during the coronavirus disease pandemic has been multisystem inflammatory syndrome in children. Reports of this condition in East Asia have been limited. In South Korea, 3 cases were reported to the national surveillance system for multisystem inflammatory syndrome in children. All case-patients were hospitalized and survived with no major disease sequelae.

Purpose Macrolide-resistant Mycoplasma pneumoniae pneumonia (MPP) is characterized by prolonged fever and radiological progression despite macrolide treatment. Few studies have examined serum procalcitonin (PCT) level in children with MPP. We aimed to investigate the association of acute inflammation markers including PCT with clinical parameters in children with MPP. Methods A total of 147 children were recruited. The diagnosis of MPP relied on serial measurement of IgM antibody against mycoplasma and/or polymerase chain reaction. We evaluated the relationships between C-reactive protein (CRP), PCT, and lactate dehydrogenase (LDH) levels and white blood cell (WBC) counts, and clinical severity of the disease. We used multivariate logistic regression analysis to estimate the odds ratio for prolonged fever (>3 days after admission) and hospital stay (> 6 days), comparing quintiles 2–5 of the PCT levels with the lowest quintile. Results The serum PCT and CRP levels were higher in children with fever and hospital stay than in those with fever lasting ≤ 3 days after admission and hospital stay ≤ 6 days. CRP level was higher in segmental/lobar pneumonia than in bronchopneumonia. The LDH level and WBC counts were higher in children with fever lasting for >3 days before compared to those with fever lasting for ≤ 3 days. The highest quintile of PCT levels was associated with a significantly higher risk of prolonged fever and/or hospital stay than the lowest quintile. Conclusion Serum PCT and CRP levels on admission day were associated with persistent fever and longer hospitalization in children with MPP.

Re s u l t s: In the norovirus group, 19 (86.4%) children showed vomiting and 21 (95.5%) children showed diarrhea, while all children in the rotaviral group showed both vomiting and diarrhea. The duration of vomiting was not different in the two groups, but mean episodes of vomiting/24 h were higher in the norovirus group than in the rotavirus group. The duration of diarrhea was longer and mean episodes of diarrhea/24 h were higher in the rotavirus group. The Vesikari Scale was not different in the two groups. Frequency and duration of fever did not show a significant difference. Most children in both groups were below 2 years of age. 2 .노로바이러스 RT ( r e v e r s et r a n s c r i p t i o n ) -PCR 방법 노로바이러스 위장관염은 대변 검체를 경기보건환경연구원에

Background and Objectives Immunological variability in Kawasaki disease (KD) shows age-specific differences; however, specific differences in laboratory values have not been compared between infants and non-infants with KD. We compared age-adjusted Z-values (Z) of white and red blood cells in infants with KD with those in non-infants with KD. Methods This study retrospectively investigated 192 infants and 667 non-infants recruited between 2003 and 2015 at the Korea University Hospital. Laboratory values for infants with KD and non-infants with KD were analyzed and age-unadjusted raw values (R) and age-adjusted Z for blood cells counts were determined. Results Z in infants with KD during pre-intravenous immunoglobulin (IVIG), post-IVIG, and chronic phases showed increased lymphopenia and eosinophilia, low neutrophil:lymphocyte and neutrophil:eosinophil ratios, worse anemia, increased thrombocytosis, and reduced erythrocyte sedimentation rates compared with those in non-infants with KD. The optimal cut-off value for pre-IVIG Z-hemoglobin for prediction of KD in all patients was <−0.01 (area under the curve [AUC], 0.914; sensitivity/specificity, 0.999/0.886; p=0.04). The optimal cut-off value for pre-IVIG C-reactive protein (CRP) for prediction of KD in infants compared to that in febrile control infants was >40 mg/L (AUC, 0.811; sensitivity/specificity, 0.712/0.700; p=0.04). Conclusions Laboratory characteristics enable differentiation between infants and non-infants with KD and contribute to a better understanding of changes in blood cell counts. Infants with incomplete KD can be more easily differentiated from infants with simple febrile illness using pre-IVIG Z-hemoglobin and pre-IVIG CRP values.