The Multifaceted Presentation of the Multisystem Inflammatory Syndrome in Children: Data from a Cluster Analysis.

BACKGROUND: The aim of this study was to evaluate the outcomes of patients with the multisystem inflammatory syndrome in children (MIS-C) according to phenotypes of disease and define the prognostic factors for the severe course. METHODS: This cross-sectional study included 293 patients with MIS-C from seven pediatric rheumatology centers. A two-step cluster analysis was performed to define the spectrum of disease and their outcomes were compared between each group. RESULTS: Four subgroups were identified as follows: cluster I, predominantly Kawasaki-like features (n = 100); cluster II, predominantly MAS-like features (n = 34); cluster III, predominantly LV dysfunction (n = 47); cluster IV, other presentations (n = 112). The duration of fever was longer in cluster II and the length of hospitalization was longer in both clusters II and III. Laboratory findings revealed lower lymphocyte and platelet counts and higher acute phase reactants (APRs) in cluster II, while patients in cluster IV showed less inflammation with lower APRs. The resolution of abnormal laboratory findings was longer in clusters II and III, while it was shortest in cluster IV. Seven patients died. Among them, four belonged to cluster II, while three were labeled as cluster III. Patients with severe course had higher levels of neutrophil-lymphocyte ratio, mean platelet volume, procalcitonin, ferritin, interleukin-6, fibrinogen, D-Dimer, BNP, and troponin-I, and lower levels of lymphocyte and platelet counts. CONCLUSION: As shown, MIS-C is not a single disease presenting with various clinical features and outcomes. Understanding the disease spectrum will provide individualized management.

The clinical course and short-term health outcomes of multisystem inflammatory syndrome in children in the single pediatric rheumatology center.

OBJECTIVES: Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe condition resulting in excessive response of the immune system after SARS-CoV-2 infection. We report a single-center cohort of children with MIS-C, describing the spectrum of presentation, therapies, clinical course, and short-term outcomes. METHODS: This is a prospective observational study from to a tertiary pediatric rheumatology center including patients (aged 1 month to 21 years) diagnosed with MIS-C between April 2020-April 2021. Demographic, clinical, laboratory results and follow-up data were collected through the electronic patient record system and analyzed. RESULTS: A total of 67 patients with MIS-C were included in the study. Fever was detected in all patients; gastrointestinal system symptoms were found in 67.2% of the patients, rash in 38.8%, conjunctivitis in 31.3%, hypotension in 26.9% myocarditis, and/or pericarditis in 22.4%, respectively. Respiratory symptoms were only in five patients (7.5%). Kawasaki Disease like presentation was found 37.3% of the patients. The mean duration of hospitalization was 11.8 7.07 days. Fifty-seven patients (85%) received intravenous immunoglobulin (IVIG), 45 (67%) received corticosteroids, 17 (25.3%) received anakinra, and one (1.5%) received tocilizumab. Seven of the patients (10.4%) underwent therapeutic plasma exchange (TPE). In 21 (31.3%) patients, a pediatric intensive care unit (PICU) was required in a median of 2 days. The first finding to improve was fever, while the first parameter to decrease was ferritin (median 6.5 days (IQR, 4-11.2 days)). Sixty-five patients were discharged home with a median duration of hospital stay of 10 days (IQR, 7-15 days). CONCLUSION: Patients with MIS-C may have severe cardiac findings and intensive care requirements in admission and hospital follow-up. The vast majority of these findings improve with effective treatment without any sequelae until discharge and in a short time in follow-up. Although the pathogenesis and treatment plan of the disease are partially elucidated, follow-up studies are needed in terms of long-term prognosis and relapse probabilities.

The clinical course of SARS-CoV-2 infection among children with rheumatic disease under biologic therapy: a retrospective and multicenter study.

The effects of biological disease-modifying antirheumatic drugs (bDMARDs) in the clinical course of COVID-19 on children with underlying rheumatologic diseases have not been fully demonstrated. To evaluate the course of COVID-19 infection in patients with rheumatic disease receiving bDMARD treatment. This was a retrospective, multicenter study conducted in pediatric patients infected by SARS-CoV-2 and under bDMARDs therapy. The study population consisted of 113 patients (72 female/41 male). The mean age of the patients was 12.87 ± 4.69 years. The primary diagnosis of the cohort was as follows: 63 juvenile idiopathic arthritis, 35 systemic autoinflammatory diseases, 10 vasculitides, and five cases of connective tissue diseases. The mean duration of the primary disease was 4.62 ± 3.65 years. A total of 19 patients had additional comorbid diseases. Thirty-five patients were treated with canakinumab, 25 with adalimumab, 18 with etanercept, 10 with infliximab, nine with tocilizumab, six with rituximab, four with anakinra, three with tofacitinib, and one with abatacept. The median exposure time of the biological drug was 13.5 months. Seventy-one patients had symptomatic COVID-19, while 42 were asymptomatic. Twenty-four patients required hospitalization. Five patients presented with MIS-C. The hospitalized patients were younger and had a shorter duration of rheumatic disease compared to ambulatory patients, although the difference was not statistically significant. Steroid usage, presence of fever, and dyspnea were more common among the hospitalized patients. A worsening in the course of both COVID-19 and current disease was not noticed under bDMARDs, however, to end with a strong conclusion multicentric international studies are required.

Evaluation of radiological findings in pediatric patients with COVID-19 in Turkey.

OBJECTIVE: The objective of the study was to describe the findings of pediatric patients diagnosed with COVID-19 in computed tomography (CT) and chest X-ray (CXR) images. Therefore, the aim of this study is to show protecting the children from radiation as much as possible while guiding the diagnosis. METHODS: Between March and June 2020, 148 pediatric patients examined who underwent CT due to suspicion of COVID-19. Fifty patients of 148 with normal thorax CT and negative reverse transcription polymerase chain reaction (RT-PCR) were excluded from the study. Of the remaining 98 patients were evaluated retrospectively by two pediatric radiologists with 15 years of experience. RESULTS: The demographic, clinical, and laboratory data were evaluated for 52 RT-PCR-positive patients. CT finding of 23 RT-PCR positive and 12 negative patients was classified. According to our study, unilateral (61-67%), multifocal (50-52%), and peripheral (83-91%) involvement were higher in all groups. Lower lobe involvement was frequently detected (58-65%). The most frequently detected parenchymal lesion was ground-glass opacity followed by consolidated areas accompanying ground-grass opacities. Halo sign and vascular enlargement signs were the common signs of lung lesions (35%). In addition, some rare findings not previously described in this disease in children were mentioned in this study. The clinical course of all our patients was mild and control radiological imaging checked by CXR. CONCLUSION: Most pediatric patients have a mild course. Hence, a balance between the risk of radiation and necessity for chest CT is very important. Low-dose CT scan is more suitable for pediatric patients but still it should be used cautiously.

Differences and similarities of multisystem inflammatory syndrome in children, Kawasaki disease and macrophage activating syndrome due to systemic juvenile idiopathic arthritis: a comparative study.

To compare the clinical and laboratory findings of multisystem inflammatory syndrome in children (MIS-C), patients with Kawasaki disease (KD) and with macrophage activating syndrome due to systemic juvenile idiopathic arthritis (sJIA-MAS) on real-life data. Patients diagnosed with MIS-C, KD, and sJIA-MAS from 12 different centers in Turkey who were followed for at least 6 months were included in the study. Demographic, clinical, and laboratory findings of all patients were analyzed. A total of 154 MIS-C, 59 KD, and 31 sJIA-MAS patients were included. The median age of patients with MIS-C were higher than those with KD while lower than those with sJIA-MAS (8.2, 3, 12 years, respectively). Myalgia (39.6%), cardiac (50.6%), gastrointestinal (72.7%), and neurological (22.1%) involvements were more common in patients with MIS-C compared to others. MIS-C patients had lower levels of lymphocyte (950 vs 1700 cells/µl) and thrombocyte (173,000 vs 355,000 cells/µl) counts and higher pro-BNP (1108 vs 55 pg/ml) levels than KD. Ferritin levels were higher in patients with MIS-C compared to patients with KD while they were lower than patients with sJIA-MAS (440, 170, 10,442 ng/ml, respectively). Patients with MIS-C had a shorter duration of hospitalization than sJIA-MAS (p = 0.02) while they required intensive care unit admission more frequently (55 vs 8 patients, p < 0.001). The median MAS/sJIA score of MIS-C patients was - 1.64 (- 5.23 to 9.68) and the median MAS/sJIA score of sJIA-MAS patients was -2.81 ([- 3.79] to [- 1.27]). MIS-C patients displayed certain differences in clinical and laboratory features when compared to KD and sJIA-MAS. Definition of the differences and similarities between MIS-C and the other intense inflammatory syndromes of childhood such as KD and MAS will help the clinicians while making timely diagnosis.

SARS-CoV-2 infection in children with rheumatic disease: Experience of a tertiary referral center.

OBJECTIVES: In this study, we present our clinical severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) experience in patients with childhood rheumatic disease during novel coronavirus-2019 (COVID-19) pandemic. PATIENTS AND METHODS: A total of 87 patients (50 males, 37 females; median age: 12 years; range, 6.6 to 16 years) suspected of having COVID-19 at our pediatric rheumatology clinic between March 11th and October 15th 2020 were retrospectively analyzed. Demographic and clinical features, treatments, laboratory results, imaging findings, and clinical outcomes of the patients diagnosed with COVID-19 and/or multisystem inflammatory syndrome in children (MIS-C) were retrieved from the medical records. The diagnosis of SARS-CoV-2 infection was made based on the reverse transcriptase-polymerase chain reaction test. RESULTS: The most common rheumatic diseases were juvenile idiopathic arthritis and familial Mediterranean fever (35.6% and 34.5%, respectively). Twenty-six of these patients were treated with biological disease-modifying anti-rheumatic drugs. SARS-CoV-2 infection was tested as positive in 84 (96.5%) patients. Also, 51 (58.6%) patients had an epidemiological contact to a person with COVID-19. Eighteen patients met the clinical criteria and diagnosed with MIS-C. The COVID-19 outbreak also caused exacerbation of systemic disease in 56 children due to medication cessation, postponed drug switch, or recurrent viral infection. CONCLUSION: Children with rheumatic disease do not appear to present a higher risk of severe COVID-19. The immunosuppressive treatments can be adjusted in case of infection; otherwise, it is not recommended to interrupt the treatments. Physicians should be cautious about the hyperinflammatory syndrome associated with COVID-19 in rheumatic children, which may be severe in this group of patients and may be confused with primary diseases.