SIDS (Sudden Infant Death Syndrome)
Definition
A diagnosis of exclusion under the AAP definition: sudden unexpected death of an infant under one year, occurring apparently during sleep, unexplained after complete autopsy, death-scene investigation, and clinical-history review. Not a synonym for SUDI (broader category of sudden unexpected death in infancy including explained causes).
- Age range
- Infants under one year
- Diagnostic requirement
- Diagnosis of exclusion - unexplained after autopsy, scene investigation, and clinical history review
Common questions
What makes SIDS different from other sudden infant deaths?+
SIDS is a diagnosis of exclusion. It applies only when a death remains unexplained after a complete autopsy, death-scene investigation, and thorough clinical history review. Other sudden unexpected infant deaths with identified causes fall into the broader category SUDI (Sudden Unexpected Death in Infancy). If a cause is found, it is not SIDS.
What age group does SIDS affect?+
SIDS applies to apparently healthy infants under one year of age. The deaths occur apparently during sleep and have no explanation despite full investigation.
Can autopsy findings alone determine SIDS?+
No. While SIDS deaths may show findings like petechiae, pulmonary congestion, or thymic petechiae, these overlap with other causes (such as smothering) and cannot pinpoint the cause. The diagnosis requires not just autopsy results but also complete scene investigation and clinical history review, with no cause found.
Related terms
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- Burking
- A combined method of homicide by simultaneous smothering (nose and mouth occlusion) and chest compression, preventing thoracic expansion. Named for William Burke...
- Channelopathy
- Ion-channel gene mutation causing potentially fatal arrhythmia without structural cardiac abnormality. The three principal forensic channelopathies are long QT syndrome (LQTS), Brugada...
- Crescentic Fingernail Abrasion
- A crescent-shaped skin abrasion produced by a fingernail during manual strangulation, with concave margin pointing toward the applied finger. Distinguishes manual throttling...
- Frenulum Tear
- A tear in the frenulum labii (the midline fold connecting the upper lip to the gum), produced by forceful smothering pressure; present...
- Gag-and-Bind Asphyxia
- Asphyxia produced by oropharyngeal or nasal obstruction from a gag combined with physical restraint preventing airway clearance; encountered in robbery, kidnapping, and...
- Hypertrophic Cardiomyopathy (HCM)
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- Manual Strangulation (Throttling)
- Asphyxia produced by application of the assailant's hands to the neck, compressing carotid arteries, jugular veins, and trachea. Produces fingertip bruising and...
- Post-Mortem Genetic Testing (Cardiac)
- Gene-panel analysis of post-mortem tissue (frozen fresh myocardium or paraffin-embedded blocks) targeting ion-channel and cardiomyopathy genes. Recommended in the UK (RCPath inherited...
- Serum Tryptase
- Enzyme released from mast cells during degranulation. Post-mortem tryptase > 11.4 ng/mL in peripheral blood is the principal biochemical marker for anaphylaxis...
- Smothering
- Asphyxia by occlusion of the external respiratory orifices (nose and mouth) without neck compression. May produce minimal or no external marks; internal...
Explained in these topics
- Manual Strangulation and SmotheringThe sudden unexpected death of an apparently healthy infant under 12 months that remains unexplained after a thorough autopsy, scene investigation, and review...
- Sudden Natural Deaths: Cardiac, SIDS, AnaphylaxisA diagnosis of exclusion under the AAP definition: sudden unexpected death of an infant under one year, occurring apparently during sleep, unexplained after co...