Related Experiment Video
Updated: Jul 2, 2026
10:08
Pseudofracture: An Acute Peripheral Tissue Trauma Model
Published on: April 18, 2011
Two-hit hypothesis and multiple organ dysfunction syndrome
1Sheffield Kidney Institute, Sheffield, UK.
JNMA; Journal of the Nepal Medical Association
|August 19, 2008
Abstract:
A severe insult in the form of infection or trauma primes the host immune system so that a subsequent, relatively trivial insult produces a markedly exaggerated host immune response, which can lead to multiple organ dysfunction syndrome (MODS) and death. This forms the basis of the "two-hit hypothesis" (THH), which is being increasingly recognised as an important cause of morbidity and mortality following severe injury and sepsis, particularly in intensive care settings. Appreciation of the impact of repeated insults and pathophysiology of MODS is vital in the prevention of this serious complication. We describe a case which illustrates the concept of THH and MODS and present a review of literature on this subject.
Insights
Severe injury or infection can prime the immune system, making a minor subsequent insult lead to a dangerous overreaction. This "two-hit hypothesis" (THH) explains multiple organ dysfunction syndrome (MODS) and mortality, especially in intensive care.
Area of Science:
- Immunology
- Critical Care Medicine
- Pathophysiology
Background:
- The
- two-hit hypothesis
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Observation:
- A severe insult primes the immune system.
- A subsequent, minor insult causes an exaggerated immune response.
- This response can lead to multiple organ dysfunction syndrome (MODS) and death.
Findings:
- The "two-hit hypothesis" (THH) describes a two-stage process.
- Priming occurs after severe injury or sepsis.
- A second, lesser insult triggers a hyperinflammatory response.
Implications:
- Understanding THH is vital for preventing MODS.
- THH is a significant factor in critical care settings.
- Further research into THH pathophysiology is needed.
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