Is there a common denominator for Brief Resolved Unexplained Events, Sudden Infant Death Syndrome, and alleged Shaken Baby Syndrome?

We propose the medical hypothesis that a common denominator may be the precursor for Brief Resolved Unexplained Events (BRUE), cases of Sudden Infant Death Syndrome (SIDS) as well as to cases of alleged Shaken Baby Syndrome (SBS) without external signs of trauma. Although previous studies have emphasized differences, we have focused on the overarching common denominators of the three conditions in terms of mechanism theories. In consequence, fatal cases with subdural hemorrhage (SDH) classified as SBS could be classified as high risk BRUE with SDH. Fatal cases without SDH could be classified as SIDS. Non-fatal cases with SDH and retinal hemorrhages (RHs), currently classified as SBS, could be classified as BRUE with SDH and RHs, leaving a fourth group of BRUE without SDH and RHs. While both the BRUE and the SIDS diagnoses have been refined and developed, alleged abusive head trauma (AHT) cases with and without external signs of trauma have been indiscriminately combined. This is analogous to indiscriminately grouping together, e.g., headache due to a brain tumor or headache after head trauma. Alleged AHT cases with external signs of trauma and high velocity impact might be explained by the traditional AHT mechanism theories, whereas the one-third of all alleged AHT cases without external signs of trauma could be explained by the hypoxia cascade theory and/or other non-shaking theories.