1. Introduction
2. Arguments
2.1. Case Definition
2.2. Initial Interventions
2.3. Differential Diagnosis
2.4. Further Evaluations
2.5. Criteria for Multisystem Inflammatory Syndrome in Children
2.6. Specific Evaluations Suspected to Have MISC
2.7. Pharmacological Interventions
2.8. Refractory Patients
Management of children with suspected COVID 19-associated multisystem inflammatory syndrome in children (MISC). 1classifiedaccording to American Heart Association criteria (15); 2 If ≥ 1 of these signs and symptoms: 1- petechial, purpuric, vesicular, or bullous Rash, 2- predominant GI symptoms: Diarrhea, abdominal pain, vomiting, 3- Neurologic Symptoms: decreased level of consciousness, seizure, cranial nerve involvement, 4- Hemodynamic instability, heart failure, or carditis, 5- Splenomegaly, 6- increase liver enzyme, hepatitis with or without jaundice, ascites, 7- Coagulopathy, 8- AND ≥ 1 of the following findings: Bicytopenia or pancytopenia (lymphopenia according to age, thrombocytopenia; 3MIS-C criteria in children; 4Second-line investigations: blood gas, lactate, fibrinogen, ferritin, troponin, N-terminal pro-B-type natriuretic peptide, D-dimer, lactate dehydrogenase, SARS-CoV-2 RT-PCR test, and serology, Septic and viral screen (lumbar puncture only if specifically indicated) ,12-lead electrocardiogram, Chest radiograph, Echocardiogram, Contrast-enhanced CT of the coronary vessels inadvisable for MISC. For children with abdominal pain who have symptoms of MISC, an abdominal ultrasound scan should be the first test to rule out other alternative diagnoses such as appendicitis; 5If evidence of coronary artery abnormality; use of IVIG with or without intravenous methylprednisolone (10 - 30 mg/kg), If progressive or unresponsive, a natural therapy should be used in children who do not answer to IVIG and methylprednisolone, infliximab is preferred for those with Kawasaki-like presentation and anakinra/ tocilizumab for others. In those small groups with the presentation of HLH, special treatment according to the consultation is recommended; 6severe disease can be considered if any of the following physiologic or biochemical features is presented, especially when there are in combination: delayed capillary tube refill time; continual hypotension; persistent tachycardia; requirement for 40 mL/kg fluid bolus; oxygen saturation < 92%, increase in CRP to 300 mg/L (some suggests > 150 mg/L); high troponin, NT-proBNP, ferritin, D-dimer, lactate dehydrogenase, creatinine, more or less fibrinogen, Cardiac symptoms like an atypical electrocardiogram, left ventricular failure or coronary artery aneurysms on echocardiogram (16); 7IN KD-like: First-line therapy for all children is IVIG at a dose of 2 g/kg, the second dose of IVIG is used for children who have not responded to the first dose of the drug. Some experts recommend that high-risk children (those that probably do not respond to IVIG according to kabashi score) or those Less than a year, and those with coronary artery changes; intravenous methylprednisolone (10 - 30 mg/kg; along with IVIG) must be prescribed at first. The second line of treatment is intravenous methylprednisolone (10 - 30 mg/kg) as the subsequent treatment choice for children who remain unwell and febrile 48 - 72 h after infusion of intravenous immunoglobulin. Biological therapy is considered as a third-line choice in children who do not reply to IVIG and methylprednisolone. In those with Kawasaki-like phenotype, infliximab is preferred (3). 8In cases of Kawasaki-like disease prescribe high dose aspirin (50 - 80 mg/kg/d) use aspirin till fever persists, and then continue with a low dose for 6 weeks. Use LMWH/enoxaparin as prophylaxis is recommended in moderate and severe cases of MISC and those children older than 12 years old (If hemorrhage and thrombocytopenia are controlled). All children over the age of 12 must wear compression stockings (13). MISC patients with coronary heart involvement or documented thrombosis should receive LMWH/ enoxaparin according to AHA protocol (15); 9In children with positive RT-PCR or with presentation consistent with typical covid-19might some experts recommend antiviral like favipiravir/ remdesivir.
