Patient handout

Multisystem inflammatory syndrome in children (MIS-C)

PRODUCTION

1. Your condition

This handout is for multisystem inflammatory syndrome in children (mis-c). Your care team identified this based on: persistent fever ≥ 24 h in child < 21 y with sars-cov-2 exposure / infection in prior 4-6 weeks (cdc mis-c 2020).

Other reasons your team may use this plan: abdominal pain / vomiting / diarrhea in child with recent covid exposure — prominent in mis-c (whittaker jama 2020 pmid 32511692); age-based hypotension / poor perfusion / ams in child with recent covid — mis-c cardiogenic shock phenotype (belhadjer circulation 2020 pmid 32418446); crp > 30 + ferritin > 500 + d-dimer > 1000 + lymphopenia + bnp/troponin elevation in child with recent covid (cdc mis-c 2020).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

Medication	Starting dose	How	When	What it does
IVIG	2 g/kg single dose IV over 10-12 h	IV	single dose	AHA 2022 + AHA/ACC 2024 + Henderson AHA 2020 Tier 1-3 — primary anti-inflammatory; reduces persistent organ dysfunction + biologic-need rate when paired with steroids (BATS observational evidence)
methylprednisolone	1-2 mg/kg/day IV ÷ q6-12h × 5 d → PO taper over 2-3 wk (mild-moderate)	IV→PO	q6-12h then taper	AHA 2022 + AHA/ACC 2024 Class I — combination with IVIG associated with shortest time to clinical improvement + lowest biologic-need rate (BATS evidence; Henderson AHA 2020 Tier 1-2)
methylprednisolone (pulse)	30 mg/kg/day IV × 1-3 d (max 1 g/d) → PO taper × 2-3 wk	IV→PO	daily × 1-3 then taper	AHA 2022 + AHA/ACC 2024 + Henderson AHA 2020 Tier 3 — pulse for severe / shock / cardiogenic / MAS overlap; mortality + ICU LOS reduced vs lower-dose in observational cohorts

Plan: MIS-C — IVIG + methylprednisolone → biologic escalation if refractory/severe → aspirin + anticoagulation per cardiac → outpatient taper + surveillance

3. Your action plan

Use these zones to know what to do based on how you feel.

GREEN — Recovering well — LV function recovering, no aneurysm or aneurysm regressing, off vasoactives

If you have:

Afebrile × 1 week (AHA 2022)
heart pumping strength (LVEF) recovering OR normal at discharge echo (AHA 2022)
No / mild coronary changes (z-score < 2.5) (AHA 2022)
CRP/ferritin/d-dimer trending normal (AHA 2022)
Tolerating PO steroid taper + aspirin (Henderson AHA 2020)
No new symptoms (AHA 2022)

Do this:

Continue PO prednisolone taper per plan (Henderson AHA 2020)
Continue low-dose aspirin 3-5 mg/kg/day × 4-6 wk minimum (AHA 2022)
Cardiology f/u at 1-2 wk + 6 wk + 1 y (AHA 2022 + AHA/ACC 2024)
Rheumatology f/u at 1-2 wk + 4-6 wk to confirm steroid taper completion (Henderson AHA 2020)
Peds-ID f/u at 4-6 wk for COVID booster planning (AAP 2024)
Avoid live vaccines for 11 mo after IVIG (AAP 2024)
COVID booster 90 d post-IVIG per peds-ID (CDC/AAP 2024)
Daily activity as tolerated; activity restrictions per cardiology if any LV abnormality or anticoagulation (AHA 2022)
Inform pediatrician + cardiologist of any new symptoms (AHA 2022)

YELLOW — Caution — new aneurysm, recurrent inflammation, medication side effects, or PICU-Family symptoms

If you have:

New / progressing coronary aneurysm on f/u echo (AHA 2022)
Recurrent fever within 4 wk of discharge (rare; AHA 2022)
Persistent / recurrent inflammation (CRP not normalizing) (AHA 2022)
Medication side effects (steroid AEs — glucose intolerance, BP, mood; GI bleed on aspirin; biologic — infection signs) (Henderson AHA 2020)
New mood / anxiety / sleep symptoms in child or caregivers (PICU-Family syndrome) (AAP)

Do this:

Contact peds-cardiology within 24 h for echo / cardiology changes (AHA 2022)
Contact peds-rheumatology within 24 h for inflammation / steroid AE concerns (Henderson AHA 2020)
Contact peds-ID within 24 h if infection signs on biologic (AHA/ACC 2024)
Mental-health referral if mood / anxiety / sleep concerns (AAP)
May need additional anti-thrombotic (clopidogrel for medium aneurysm; LMWH/warfarin for large) (AHA 2017 KD precedent + AHA 2022)
Recurrent fever → repeat MIS-C workup OR alternative diagnosis evaluation (AHA 2022)
Bring child to ED if signs of bleeding (GI bleed, easy bruising, hematuria) or coronary ischemia (chest pain, syncope) (AHA 2022)

Call your provider if:

Any aneurysm progression or new aneurysm (AHA 2022)
Recurrent fever (AHA 2022)
Medication side effects (Henderson AHA 2020)
New mental-health concerns (AAP)

RED — Emergency — coronary ischemia, severe bleeding, recurrent shock, status epilepticus, suicidality

If you have:

Chest pain in child with prior MIS-C / coronary aneurysm (AHA 2022)
Syncope, sudden collapse (AHA 2022)
Severe bleeding on antiplatelet/anticoagulant (GI bleed, intracranial hemorrhage) (AHA 2022)
Recurrent shock with multi-system findings (rare; consider MIS-C relapse or new sepsis) (AHA 2022)
Status epilepticus (route to peds.status_epilepticus.v1)
Stroke symptoms (focal neuro deficit) (AHA 2022)
Suicidality in child or caregiver (AAP)

Do this:

Call 911 immediately (AHA 2022)
Bring all medications + MIS-C records (AHA 2022)
Identify as MIS-C patient with cardiac involvement if applicable (AHA 2022)
Pediatric cardiac center transfer if available + ECMO-capable for refractory cardiac (AHA 2022 + ELSO 2023)

Call your provider if:

Any red zone trigger — go to ED, do not wait (AHA 2022)

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

MIS-C with cardiogenic shock OR severe LV dysfunction (heart pumping strength (LVEF) < 35) OR requiring high-dose vasoactive support (epi ≥ 0.3 µg/kg/min OR norepi ≥ 0.5 µg/kg/min)(life-threatening)
Coronary aneurysm Z ≥ 10 OR absolute diameter ≥ 8 mm at presentation OR rapidly expanding aneurysm on serial echo(life-threatening)
Persistent fever / persistent inflammation / persistent organ dysfunction at 36-48 h after completion of IVIG + methylprednisolone (refractory MIS-C)
MIS-C with encephalopathy / seizure / focal neurologic deficit / cranial nerve palsy / meningismus / new severe headache
MIS-C in immunocompromised host — transplant / oncology / on biologics or chemo / primary immunodeficiency / on DMARDs
MIS-C-like presentation beyond 4 weeks after documented SARS-CoV-2 exposure / infection OR persistent SARS-CoV-2 PCR positivity with chronic inflammation
MIS-C with macrophage activation syndrome features — ferritin > 10,000 ng/mL + bicytopenia / pancytopenia + LFT > 3-5x ULN + hypofibrinogenemia + hypertriglyceridemia + ± hemophagocytosis on bone marrow (rare to obtain in MIS-C acute)(life-threatening)

5. Follow-up

Outpatient peds-cardiology + peds-rheum + peds-ID f/u at 1-2 wk + 6 wk + 1 y per AHA 2022; aspirin 3-5 mg/kg/d × 4-6 wk (longer if coronary aneurysm); steroid taper PO over 2-3 wk; live vaccine deferral × 11 mo after IVIG (AAP 2024); COVID booster timing per peds-ID (defer 90 d after IVIG or per recovery); neurodev screening if neuro-involvement; transition to adult cardiology if persistent aneurysm

6. Sources

Guideline: CDC MIS-C Case Definition 2020 + 2023 update + AHA 2022 MIS-C management update + AHA/ACC 2024 MIS-C management update + Henderson AHA 2020 ACR/AHA tiered approach (Arthritis Rheumatol 2020) + BATS observational study + RECOVERY-C trial data