Multisystem Inflammatory Syndrome in Children after SARS-CoV-2 Vaccination
Multisystem inflammatory syndrome in children (MIS-C) and adults (MIS-A) can follow SARS-CoV-2 infection. MIS-C was primarily described for 16-20 year olds, racial/ethnic minority populations and children with comorbidities.
MIS-C and MIS-A can be also induced by vaccination without current COVID-19 infection. In adults, many individuals who experienced it were vaccinated 11-78 days after COVID-19-like illness. One case when a 30-year-old male was vaccinated 6 and 28 days after positive test was fatal. In children, only ~25% had COVID-19 in the past. Average age was lower than in MIS-C triggered by the virus.
Here are a few case reports.
A 12-year-old male was presented to the hospital with acute encephalopathy, headache, vomiting, diarrhea, and elevated troponin two days after the second dose of the Pfizer-BioNTech COVID-19 vaccine. Symptoms developed within 24 h. Brain magnetic resonance imaging revealed a cytotoxic splenial lesion of the corpus callosum (CLOCC). Three weeks after hospital discharge, all of his symptoms had dissipated, and he had a normal neurologic exam. The child recovered without receipt of immune modulatory treatment.
A previously healthy 12-year-old male presented with a 4-day duration of fever, eye redness, diarrhea, neck pain and swelling that started 27 days before his first dose of Pfizer-BioNTech COVID-19 vaccine.He had no history of COVID-19 infection or exposure. He had a negative anti-SARS-CoV-2 nucleocapsid total antibody level, but a high level of anti-SARS-CoV-2 spike IgG (257 BAU/mL; >0.8 BAU/mL: positive result), indicating a vaccine-induced antibody response rather than a SARS-CoV-2 infection-induced antibody response. He was treated with IVIG (2 g/kg) and methylprednisolone (2 mg/kg). He was discharged 5 days after admission with no sequela or complication.
A 12-year-old boy presented by continuous, high-grade fever for 3 days, redness of eyes, followed by a diffuse erythematous non-itchy rash, fatigue and abdominal pain, 5 weeks after his second dose of Moderna vaccine that was preceded by the first dose of Pfizer-BioNTech vaccine given 3 weeks apart. He had no history of COVID-19 infection or exposure. He was treated with intravenous fluids, acetaminophen, antibiotics and intravenous immunoglobulin. One week after discharge he only had residual mild fatigue.
A 15-year-old boy with a history of mild COVID-19 received the first dose of COVID-19 messenger RNA vaccine (Moderna) 50 days later. On post-vaccination day 1, the patient developed fever, lethargy, headache, diarrhea, nausea, lip swelling, and right neck pain. On post-vaccination day 4, he sought medical consultation because his condition worsened. Intravenous immunoglobulin (IVIG) was initiated at 1 g/kg/day, and oral aspirin was started at 200 mg (3 mg/kg/day). The patient subsequently recovered without relapse.
A 15-year-old girl with asthma received her first dose of BNT162b2 6 days before seeking care. She had low-grade fever and myalgia, which resolved within 2 days of vaccination. Four days later, she experienced 102°F fevers, headaches, nonbilious emesis, bilateral conjunctivitis, myalgias, chest pain, pharyngeal erythema and a diffuse blanching rash. She was negative for SARS-CoV-2. She was admitted to the pediatric intensive care unit (ICU) and given 2 g/kg intravenous immune globulin (IVIG) for suspected of Multisystem Inflammatory Syndrome in Children MIS-C. The patient fully recovered.