peds.mis-c.v1PRODUCTION

peds.mis-c.v1

Multisystem inflammatory syndrome in children (MIS-C)

pediatricsacutesyndromepediatric

Hard-required inputs

0 / 25

Care setting:

Encounter flow

12/12 authored

Canonical 12-phase frame with authored status for this dossier.

Current phase

Frame

Detailed

MIS-C per CDC 2020 + 2023 — age < 21 y + fever ≥ 24 h + ≥ 2 organ systems + lab inflammation + SARS-CoV-2 evidence + no alt dx. Distinguish from Kawasaki (older age, GI prominence, myocarditis with reduced LVEF vs coronary aneurysm).

Inputs

Actions

Advance rule

Set

Advance when

MIS-C pattern identified per CDC 2020

Patient inputs (29)

age*demographic • CONTEXT

CDC MIS-C 2020 requires age < 21 y; peak incidence 5-12 y vs KD 6 mo-5 y (Feldstein NEJM 2020 PMID 32598831)

temperature*vital • CONTEXT

Fever ≥ 24 h required for CDC MIS-C 2020 criteria

sbp*vital • CONTEXT

Age-based hypotension threshold → cardiogenic shock / severe-MIS-C trigger (Belhadjer Circulation 2020)

hr*vital • CONTEXT

Age-based tachycardia → severity indicator (Phoenix sepsis-style framing)

spo2*vital • CONTEXT

Hypoxaemia indicates respiratory / cardiac compromise; intubation decision (AHA 2022)

sars_cov_2_evidence*history • CONTEXT

not present

CDC MIS-C 2020 requires PCR / serology / antigen / exposure within 4 weeks

covid_vaccination_history*history • CONTEXT

not present

Vaccination status modifies likelihood + informs post-recovery COVID booster timing (CDC + AAP 2024)

immunocompromise_peds*history • CONTEXT

not present

Transplant / oncology / biologics → broader workup + tiered escalation (AHA/ACC 2024)

gi_symptoms*symptom • INITIAL_WORKUP

Abdominal pain / vomiting / diarrhea — prominent in MIS-C ~ 60-90% (Whittaker JAMA 2020)

mucocutaneous_findings*symptom • INITIAL_WORKUP

Conjunctivitis / rash / lip-oral changes — KD-overlap evaluation (Henderson AHA 2020)

crp*lab • INITIAL_WORKUP

CRP > 30 mg/dL supports hyperinflammation (CDC MIS-C 2020 inflammation criterion)

ferritin*lab • INITIAL_WORKUP

Ferritin > 500 supports MIS-C; > 10,000 → consider MAS overlap (Henderson AHA 2020)

d_dimer*lab • INITIAL_WORKUP

D-dimer > 1000 ng/mL supports hyperinflammatory + coagulopathy in MIS-C

troponin*lab • INITIAL_WORKUP

Troponin elevation supports myocarditis in MIS-C (Belhadjer Circulation 2020)

bnp_or_ntprobnp*lab • INITIAL_WORKUP

BNP / NT-proBNP elevation supports MIS-C cardiac involvement (AHA 2022)

wbc*lab • INITIAL_WORKUP

Lymphopenia + neutrophilia pattern supports MIS-C (Whittaker JAMA 2020)

platelets*lab • INITIAL_WORKUP

Thrombocytopenia early; recovery thrombocytosis subacute (Whittaker JAMA 2020)

creatinine*lab • INITIAL_WORKUP

AKI complicates MIS-C (CDC organ-system criterion)

sars_cov_2_pcr*lab • INITIAL_WORKUP

CDC criterion — current infection (AAP Red Book 2024)

sars_cov_2_serology*lab • INITIAL_WORKUP

CDC criterion — prior infection within 4 weeks (most common evidence in MIS-C)

blood_culture*lab • INITIAL_WORKUP

Exclude bacterial sepsis (CDC MIS-C exclusion criterion)

echocardiogram*imaging • INITIAL_WORKUP

not present

LVEF + coronary z-score + pericardial effusion at baseline + 1-2 wk + 6 wk + 1 y (AHA 2022 + AHA/ACC 2024 MIS-C surveillance)

ecg*imaging • INITIAL_WORKUP

not present

Arrhythmia / conduction / myocarditis screen at presentation (AHA 2022)

mental_status_child*symptom • RED_FLAGS

Neuro-involvement (encephalopathy / seizure / focal deficit) = severity marker (CDC MIS-C 2020 + AHA/ACC 2024)

weight*demographic • TREATMENT

IVIG 2 g/kg + methylprednisolone 1-2 mg/kg/d + biologic dosing all weight-based (AHA 2022)

esrlab • INITIAL_WORKUP

ESR elevated supports inflammation (CDC MIS-C 2020)

albuminlab • INITIAL_WORKUP

Hypoalbuminemia ≤ 3 g/dL = severity marker (Henderson AHA 2020)

altlab • INITIAL_WORKUP

Hepatitis pattern common in MIS-C (Whittaker JAMA 2020)

fibrinogenlab • INITIAL_WORKUP

Hypofibrinogenemia → MAS overlap (Henderson AHA 2020)

* = hard-required. Engine cannot meaningfully run until these are filled.

Severity triggers (8)

8 need judgement

informationallife_threateningmis_c_with_cardiogenic_shock_or_severe_lv_dysfunction
MIS-C with cardiogenic shock OR severe LV dysfunction (LVEF < 35) OR requiring high-dose vasoactive support (epi ≥ 0.3 µg/kg/min OR norepi ≥ 0.5 µg/kg/min)
Trigger could not be auto-evaluated — needs clinician judgement.
informationallife_threateningmis_c_with_coronary_aneurysm_emergent
Coronary aneurysm Z ≥ 10 OR absolute diameter ≥ 8 mm at presentation OR rapidly expanding aneurysm on serial echo
Trigger could not be auto-evaluated — needs clinician judgement.
informationallife_threateningmis_c_with_macrophage_activation_syndrome
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)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalsevereivig_refractory_mis_c_at_36_48h
Persistent fever / persistent inflammation / persistent organ dysfunction at 36-48 h after completion of IVIG + methylprednisolone (refractory MIS-C)
Trigger could not be auto-evaluated — needs clinician judgement.
informationalseveremis_c_with_neuro_involvement
MIS-C with encephalopathy / seizure / focal neurologic deficit / cranial nerve palsy / meningismus / new severe headache
Trigger could not be auto-evaluated — needs clinician judgement.
informationalseveremis_c_in_immunocompromised
MIS-C in immunocompromised host — transplant / oncology / on biologics or chemo / primary immunodeficiency / on DMARDs
Trigger could not be auto-evaluated — needs clinician judgement.
informationalseveremis_c_late_presentation_beyond_4_weeks
MIS-C-like presentation beyond 4 weeks after documented SARS-CoV-2 exposure / infection OR persistent SARS-CoV-2 PCR positivity with chronic inflammation
Trigger could not be auto-evaluated — needs clinician judgement.
informationalmoderatemis_c_vs_kawasaki_overlap_features
MIS-C with full Kawasaki criteria met (fever ≥ 5 d + ≥ 4 of 5 principal: bilateral nonexudative conjunctivitis, oral changes, polymorphous rash, extremity changes, cervical lymphadenopathy)
Trigger could not be auto-evaluated — needs clinician judgement.

Workflow calculators

This dossier does not reference any calculators.

Recommended regimen

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

axis: mis_c_acute_4stagestep 1 - Stage 1 — IVIG + methylprednisolone (first-line, all confirmed MIS-C)

Selected step "Stage 1 — IVIG + methylprednisolone (first-line, all confirmed MIS-C)" — CDC MIS-C 2020 criteria met OR strongly suspected MIS-C with shock features

IVIG
first line
immunoglobulin
2 g/kg single dose IV over 10-12 h • IV • single dose
triggers: mis_c_diagnosis_confirmed_or_strongly_suspected
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)
rxcui 1426680
methylprednisolone
first line
corticosteroid
1-2 mg/kg/day IV ÷ q6-12h × 5 d → PO taper over 2-3 wk (mild-moderate) • IV→PO • q6-12h then taper
triggers: mis_c_tier_1_or_tier_2_henderson_aha_2020
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)
rxcui 6902
methylprednisolone (pulse)
first line
corticosteroid
30 mg/kg/day IV × 1-3 d (max 1 g/d) → PO taper × 2-3 wk • IV→PO • daily × 1-3 then taper
triggers: mis_c_tier_3_severe_or_cardiogenic_shock_or_mas_overlap
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
rxcui 6902

outpatient playbook — drug actions (6)

1. prednisolone PO taper continuation
Per discharge taper plan; typically over 2-3 wk (longer if relapse risk) • PO • daily taper
trigger: Post-discharge with steroid continuation
Henderson AHA 2020 — no abrupt stop; relapse risk markers (persistent CRP, severe LV at peak) → longer taper
2. aspirin low-dose continuation
3-5 mg/kg/day PO once daily × 4-6 wk total (longer if coronary aneurysm) • PO • once daily
trigger: Post-discharge MIS-C
AHA 2022; indefinitely if persistent aneurysm (AHA 2017 KD precedent)
3. enoxaparin OR warfarin continuation
Per discharge plan; until EF normalized + no thrombus • SC or PO • per agent
trigger: Discharge with anticoagulation indication
AHA 2022 — discontinue when EF normalized + no aneurysm + no thrombus per cardiology
4. COVID booster (deferred timing)
Per ACIP age-based schedule • IM • per ACIP
trigger: 90 d post-IVIG OR per peds-ID assessment of clinical recovery
CDC/AAP 2024 — booster after clinical recovery + IVIG washout; protect against MIS-C recurrence + severe COVID
5. live vaccines (MMR, varicella, rotavirus) deferred
Per ACIP age-based schedule • SC or PO • per ACIP
trigger: 11 mo post-IVIG (AAP 2024)
IVIG interferes with live-vaccine immunogenicity; defer to ensure efficacy
6. inactivated vaccines (PCV, Hib, DTaP, influenza)
Per ACIP age-based schedule • IM • per ACIP
trigger: Post-recovery + per peds-ID
AAP Red Book 2024 — no IVIG interference with inactivated vaccines; catch up routine schedule

Auto-drafted A&P note

outpatient

Subjective

- Possible entry pathways: Persistent fever ≥ 24 h in child < 21 y with SARS-CoV-2 exposure / infection in prior 4-6 weeks (CDC MIS-C 2020); 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).

Objective

- No vitals, labs, or imaging entered for this encounter.

Assessment

**Multisystem inflammatory syndrome in children (MIS-C)** (peds.mis-c.v1).
Phenotype framing: Phenotype: full MIS-C / KD-overlap MIS-C / MIS-C with shock-dominant / MIS-C with neuro / MIS-C with MAS overlap; rule out: bacterial sepsis with positive culture, TSS, appendicitis, leptospirosis, atypical viral, autoimmune flare, primary cardiomyopathy
Scope: MIS-C per CDC 2020 + 2023 — age < 21 y + fever ≥ 24 h + ≥ 2 organ systems + lab inflammation + SARS-CoV-2 evidence + no alt dx. Distinguish from Kawasaki (older age, GI prominence, myocarditis with reduced LVEF vs coronary aneurysm).

No severity triggers fired against current inputs.

Plan

Regimen axis: **MIS-C — IVIG + methylprednisolone → biologic escalation if refractory/severe → aspirin + anticoagulation per cardiac → outpatient taper + surveillance** — step "Stage 1 — IVIG + methylprednisolone (first-line, all confirmed MIS-C)".
1. IVIG 2 g/kg single dose IV over 10-12 h IV single dose (immunoglobulin, first line) — 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)
2. 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 (corticosteroid, first line) — 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)
3. 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 (corticosteroid, first line) — 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

Setting playbook (outpatient) — Long-term cardiac surveillance + steroid taper + aspirin + immunization + COVID booster planning + neurodev follow-up if neuro-involvement + transition to adult cardiology if persistent aneurysm
4. prednisolone PO taper continuation Per discharge taper plan; typically over 2-3 wk (longer if relapse risk) PO daily taper — Post-discharge with steroid continuation (Henderson AHA 2020 — no abrupt stop; relapse risk markers (persistent CRP, severe LV at peak) → longer taper)
5. aspirin low-dose continuation 3-5 mg/kg/day PO once daily × 4-6 wk total (longer if coronary aneurysm) PO once daily — Post-discharge MIS-C (AHA 2022; indefinitely if persistent aneurysm (AHA 2017 KD precedent))
6. enoxaparin OR warfarin continuation Per discharge plan; until EF normalized + no thrombus SC or PO per agent — Discharge with anticoagulation indication (AHA 2022 — discontinue when EF normalized + no aneurysm + no thrombus per cardiology)
7. COVID booster (deferred timing) Per ACIP age-based schedule IM per ACIP — 90 d post-IVIG OR per peds-ID assessment of clinical recovery (CDC/AAP 2024 — booster after clinical recovery + IVIG washout; protect against MIS-C recurrence + severe COVID)
8. live vaccines (MMR, varicella, rotavirus) deferred Per ACIP age-based schedule SC or PO per ACIP — 11 mo post-IVIG (AAP 2024) (IVIG interferes with live-vaccine immunogenicity; defer to ensure efficacy)
9. inactivated vaccines (PCV, Hib, DTaP, influenza) Per ACIP age-based schedule IM per ACIP — Post-recovery + per peds-ID (AAP Red Book 2024 — no IVIG interference with inactivated vaccines; catch up routine schedule)

Non-pharmacologic actions:
- Peds-cardiology long-term f/u (AHA 2022 — to 1 y minimum; lifelong if persistent aneurysm)
- Peds-rheumatology f/u for steroid taper completion + inflammatory recurrence screen (Henderson AHA 2020)
- Peds-ID f/u for COVID booster planning + post-acute COVID sequelae screen (AAP 2024)
- Neurodev referral if neuro-involvement during acute (Bayley III < 3 yo; ASQ 1 mo - 5.5 yo; PEDS:DM 3-8 yo) (AAP)
- Mental health referral for child + caregivers if PICU-Family syndrome features (PHQ-9-A ≥ 12 yo; SCARED anxiety; PCL-5 PTSD) (AAP)
- PT/OT referral if functional decline post-PICU (Choong PEDAL series equivalent for MIS-C survivors)
- School re-entry plan with activity restrictions per cardiology (no contact sports if anticoagulated)
- Family adherence support + return-precaution education (fever recurrence within 4 wk, chest pain, syncope, neuro changes) (AHA 2022)
- Transition planning to adult cardiology if persistent giant aneurysm into adolescence (AHA 2017 KD precedent + AHA 2022)

AVOID / contraindication checks:
- Delay live vaccines 11 months after IVIG (AAP 2024)
- ASA Reye risk during VZV or influenza exposure (AHA 2017 McCrindle) — substitute clopidogrel during exposure
- IVIG premedicate diphenhydramine + acetaminophen + monitor for infusion reaction (AHA 2022)
- Steroid taper no abrupt stop (Henderson AHA 2020)
- Warfarin INR 2 3 for severe LV / large aneurysm (AHA 2017 + AHA 2022)
- Biologic TB screen + hepatitis screen + live vaccine prior + infusion reaction premedication (AHA/ACC 2024)
- Anakinra renal dose adjustment CrCl < 30 mL/min (DailyMed label)
- Infliximab heart failure caution NYHA III contraindication; avoid in severe LV dysfunction without expert consult (DailyMed label)
- Tocilizumab GI perforation risk + LFT monitoring + neutropenia risk (DailyMed label)
- COVID booster timing defer 90 days after IVIG OR after clinical recovery + per peds ID (CDC/AAP 2024)

Monitoring

Regimen monitoring:
- temperature q4h until afebrile 48-72h post-treatment (AHA 2022)
- CRP + ferritin + d-dimer + troponin + BNP q1-2 days during acute (AHA 2022)
- CBC + CMP + LFT q1-2 days during acute (AHA 2022)
- echocardiogram at baseline + 1-2 wk + 6 wk + 1 y (AHA 2022 + AHA/ACC 2024 MIS-C surveillance)
- ECG at diagnosis + pre-discharge + 1-2 wk (AHA 2022)
- IVIG response assessment at 36-48 h — biologic-escalation decision (Henderson AHA 2020)
- steroid AEs — glucose q6h during high-dose, BP, GI bleed screen (AHA 2022)
- biologic AEs — infection screen, infusion reaction, LFT for tocilizumab (DailyMed)
- long-term cardiology follow-up to 1 y minimum; lifelong if persistent aneurysm (AHA 2022)
- live vaccine schedule adjusted for IVIG 11 mo (AAP 2024); COVID booster per peds-ID

Setting (outpatient) monitoring:
- Peds-cardiology q1-2 wk × 6 wk, then 3 mo, 6 mo, 1 y (AHA 2022)
- Echo per schedule (AHA 2022)
- Inflammation labs (CRP + ferritin + d-dimer) at 1-2 wk + 6 wk + 3 mo (AHA 2022)
- CBC + LFT + glucose during steroid taper (AHA 2022)
- Neurodev re-assessment at 6 mo + 12 mo if applicable (AAP)
- Mental health re-screen at 3 mo + 6 mo + 12 mo (AAP)
- Vaccination status audit at every visit until caught up (AAP Red Book 2024)

Follow-up plan: 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
- Close-out criterion: Long-term cardiac plan + immunization plan + transition plan documented

Monitoring phase: Daily fever curve + CRP/ferritin/d-dimer/troponin/BNP trend; serial echo at baseline + 1-2 wk + 6 wk + 1 y (AHA 2022 + AHA/ACC 2024); ECG; IVIG infusion reactions; steroid AEs (glucose, BP, GI bleed); biologic AEs (infection, infusion reaction)

Disposition

Current setting: outpatient — Long-term cardiac surveillance + steroid taper + aspirin + immunization + COVID booster planning + neurodev follow-up if neuro-involvement + transition to adult cardiology if persistent aneurysm

Disposition criteria:
- Sustained recovery — afebrile + normal echo at 6 wk + normal inflammation labs + steroid off + aspirin completed (4-6 wk min) + immunization plan complete + neurodev within age-appropriate range + mental-health screens negative + family demonstrating return-precaution knowledge (AHA 2022 + AAP)

Escalation triggers (move to higher acuity):
- Recurrent fever / inflammation within 4 wk of discharge → ED + repeat MIS-C workup (rare relapse) (AHA 2022)
- New chest pain / syncope in aneurysm patient → ED + cardiology urgent (AHA 2017 + AHA 2022)
- New focal neurological deficit / seizure → ED + neurology urgent; route to peds.status_epilepticus.v1 if seizing
- Functional decline at f/u → developmental peds + PT/OT urgent (AAP)
- Severe mental-health concerns (PHQ-9-A ≥ 15; PCL-5 elevated; suicidality) → mental-health urgent (AAP)
- New aneurysm progression on serial echo → cardiology urgent + consider escalation to anticoagulation (AHA 2017 + AHA 2022)

Patient Action Plan

**MIS-C post-discharge action plan — cardiac surveillance + medication adherence + return precautions**
Personalised values: lvef_at_discharge, coronary_z_score_at_discharge, medication_regimen, age_for_dosing, covid_vaccination_status, ivig_administration_date.

**Recovering well — LV function recovering, no aneurysm or aneurysm regressing, off vasoactives** (green):
Triggers:
- Afebrile × 1 week (AHA 2022)
- 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)
Actions:
- 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)

**Caution — new aneurysm, recurrent inflammation, medication side effects, or PICU-Family symptoms** (yellow):
Triggers:
- 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)
Actions:
- 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)
Contact provider when:
- Any aneurysm progression or new aneurysm (AHA 2022)
- Recurrent fever (AHA 2022)
- Medication side effects (Henderson AHA 2020)
- New mental-health concerns (AAP)

**Emergency — coronary ischemia, severe bleeding, recurrent shock, status epilepticus, suicidality** (red):
Triggers:
- 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)
Actions:
- 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)
Contact provider when:
- Any red zone trigger — go to ED, do not wait (AHA 2022)

Earlier-Return Triggers

Return-precaution thresholds (watch for):
- [LIFE_THREATENING] MIS-C with cardiogenic shock OR severe LV dysfunction (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] 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)

Citations

- 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 [PMID:32418446](https://pubmed.ncbi.nlm.nih.gov/32418446/)
- Cited evidence (PMID 32511692) [PMID:32511692](https://pubmed.ncbi.nlm.nih.gov/32511692/)
- Cited evidence (PMID 32598831) [PMID:32598831](https://pubmed.ncbi.nlm.nih.gov/32598831/)
- Cited evidence (PMID 32705809) [PMID:32705809](https://pubmed.ncbi.nlm.nih.gov/32705809/)

Last reconciled with current guidelines: 2026-05-15.

References

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 — PMID:32418446
Cited evidence (PMID 32511692) — PMID:32511692
Cited evidence (PMID 32598831) — PMID:32598831
Cited evidence (PMID 32705809) — PMID:32705809