Cited by 3,196COVID-19 Clinical Research StudiesAutoimmune and Inflammatory Disorders ResearchSepsis Diagnosis and Treatment

The DOI matches its Crossref record; 113 of the 113 references it cites were found in a registry or an index; 8 of the 109 sources its claims cite were checked for support.

Cytokine Storm

Open access
Fajgenbaum, David C., June, Carl H.·2020·New England Journal of Medicine

Abstract

Cardiac disorders CTCAE Term Grade 1 Grade 2 Grade 3 Grade 4 Grade 5 Pericarditis Asymptomatic, ECG or physical findings (e.g., rub) consistent with pericarditis Definition: A disorder characterized by flaky and dull skin; the pores are generally fine, the texture is a papery thin texture.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This review proposes a unifying definition of cytokine storm as elevated circulating cytokine levels, acute systemic inflammatory symptoms, and secondary organ dysfunction beyond a normal pathogen response (or cytokine-driven organ dysfunction if no pathogen is present). It synthesizes mechanisms, causes, and treatments across iatrogenic, pathogen-induced, neoplastic/autoimmune/monogenic, and Covid-19-associated cytokine storm.

Key findings

  • The authors propose three criteria for cytokine storm: elevated circulating cytokine levels, acute systemic inflammatory symptoms, and either secondary organ dysfunction due to inflammation beyond that attributable to a normal pathogen response (if a pathogen is present) or any cytokine-driven organ dysfunction (if no pathogen is present). Improvement with cytokine neutralization or antiinflammatory agents further supports the classification.
  • Key cytokines implicated include interferon-γ, interleukin-1, interleukin-6, TNF, and interleukin-18. Interleukin-6 is highly elevated in CAR T-cell therapy–induced cytokine storm and several other cytokine storm disorders; tocilizumab and siltuximab have shown effectiveness in HLH, idiopathic multicentric Castleman’s disease, and CAR T-cell–induced cytokine storm. Emapalumab was recently approved for primary HLH, and anakinra is effective in some forms of cytokine storm.
  • Causes span iatrogenic triggers (CAR T cells, blinatumomab, TGN1412, rituximab, gene therapies, immune checkpoint inhibitors, cardiac-bypass surgery, allogeneic stem-cell transplantation), pathogens (sepsis, EBV/CMV-associated HLH, HHV-8–associated multicentric Castleman’s disease, influenza), monogenic/autoimmune disorders (primary HLH mutations in PRF1, UNC13D, STXBP1, RAB27A, STX11, SH2D1A, XIAP, NLRC4; autoinflammatory diseases), and Covid-19.
  • In Covid-19, elevated cytokines include interleukin-1β, interleukin-6, IP-10, TNF, interferon-γ, MIP1α and MIP1β, and VEGF; higher interleukin-6 levels are strongly associated with shorter survival. Dexamethasone reduces mortality among the most severe cases with elevated CRP and supplemental oxygen requirements, whereas two large randomized controlled trials of anti–interleukin-6 receptor therapies did not show a survival benefit in hospitalized patients with Covid-19.

Methods

  • Narrative review; no primary study design, sample, or statistical analysis is reported. The authors synthesize literature and propose a unifying definition and conceptual framework for staging, assessment, and treatment of cytokine storm.
  • The review discusses pathophysiological features, clinical presentation, management, and iatrogenic, pathogen-induced, neoplasia-induced, monogenic, and Covid-19–associated causes. No systematic search strategy or meta-analysis is described.

Limitations

  • Stated: no single definition of cytokine storm or cytokine release syndrome is widely accepted, and there is disagreement about how these disorders differ from an appropriate inflammatory response; the National Cancer Institute CTCAE definition is too broad, and the American Society for Transplantation and Cellular Therapy definition focuses too specifically on iatrogenic causes.
  • Stated: the authors do not propose a specific threshold for cytokine elevations above normal or recommend specific cytokine panels or particular cytokines that must be elevated, given the lack of available evidence; they call for future systematic assessment by a multidisciplinary consortium.
  • Stated and evident: mechanisms of Covid-19–associated cytokine storm remain unclear, including whether immune hyperactivity or failure to resolve inflammation underlies severe cases; as a narrative review, it provides no primary data, systematic search, or formal risk-of-bias assessment.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1056/nejmra2026131

Cites

113 of 113 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

83 Not checked yet · 51 Own interpretation · 40 No basis given · 3 Partly supported · 1 Supported · 1 Not supported · accuracy not yet measured

Verify all 101 references — free account

Show all 90 claims

  • It may state two separate claims as one. 59
  • Probably not a substantial claim. 52
89 of 89
  • The paper relies on this without support.

    The immune system is expected to recognize foreign invaders, respond proportionally to the pathogen burden, and then return to homeostasis.

    “The immune system is expected to recognize foreign invaders, respond proportionally to the pathogen burden, and then return to homeostasis.”
  • The paper relies on this without support.

    Cytokines have short half-lives, which normally prevents them from having effects outside lymphoid tissue and sites of inflammation.

    “Cytokines have short half-lives, which normally prevents them from having effects outside lymphoid tissue and sites of inflammation.”
  • The paper relies on this without support.

    The immune response to SARS-CoV-2 is critical for controlling viral replication and clearance.

    “when the immune response to SARS-CoV-2 is critical in controlling viral replication and clearance.”
  • The paper relies on this without support.

    No unifying definition of cytokine storm exists.

    “No unifying definition of cytokine storm exists”
  • The paper relies on this without support.

    There is much disagreement about what the definition of cytokine storm should be and whether specific conditions such as Covid-19 should be included in the spectrum of cytokine storm disorders.

    “there is much disagreement about what the definition should be and whether specific conditions such as Covid-19 should be included in the spectrum of cytokine storm disorders.”
5 of 5

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Citations

Cites

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Metadata

Authors
Fajgenbaum, D. C., & June, C. H.
Affiliations
  • University of Pennsylvania (US)
  • Parker Institute for Cancer Immunotherapy (US)
Corresponding author
June, Carl H.
Venue
New England Journal of Medicine
Published
2020-12-03
Volume
383
Issue
23
Pages
2255-2273
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
OpenAlex
W3112902030
Cited by
3,196
References
113
Citations by year
2026: 304 · 2025: 438 · 2024: 534 · 2023: 592 · 2022: 711 · 2021: 601 · 2020: 10
FWCI
22.68
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health (2r01hl141408-06)
  • National Heart, Lung, and Blood Institute (R01-HL141408)
  • National Cancer Institute (P01CA214278)
Topics
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
  • Health Sciences › Medicine › Hematology › Autoimmune and Inflammatory Disorders Research
  • Health Sciences › Medicine › Critical Care and Intensive Care Medicine › Sepsis Diagnosis and Treatment
Keywords
cytokine storm, pericarditis, heart disease, CTCAE grading, adverse event definitions
MeSH terms
Cytokine Release Syndrome, COVID-19, Autoimmune Diseases, Bacterial Infections, Blood Proteins, Humans, Interleukins, Virus Diseases, Cytokines, Chemokines

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