Hypothesis: new concepts concerning the pathophysiology of the sudden infant death syndrome due to magnesium deficiency shock.

There appear to be many contributing factors to sudden infant death syndrome (SIDS). One final common pathway that may explain some cases of SIDS is presented as a hypothesis: SIDS occurs as a shock-like event in a stressed infant with congenital or acquired magnesium deficiency with respect to calcium, or with genetically determined high magnesium requirements. Increased calcium and stress-related catecholamines favour platelet aggregation and release of mediators, chief of which appears to be thromboxane A2 (TXA2). TXA2, a major vasoconstrictor, bronchoconstrictor, and platelet aggregator is relatively unopposed during shock by prostacyclin, a vasodilator, bronchodilator, and platelet disaggregator which normally counterbalances its effects. The shock episode is self-limited. Infants who recover have suffered an apparent life threatening event (ALTE); those who die have insufficient pathology to explain the cause of death; the diagnosis is SIDS.