PEDIATRICS Vol. 107 No. 4 April 2001, pp. 809

One More Thought on Sudden Infant Death Syndrome

To the Editor.

The American Academy of Pediatrics (AAP) Task Force on Infant Sleep Position and Sudden Infant Death Syndrome (SIDS) has identified a number of risk factors for SIDS, including prone sleeping, SIDS among siblings, infanticide, and cardiac arrhythmias.¹ However, one important and preventable risk factor was omitted. This factor, a metabolic disorder of fatty acid oxidationnotably, but not exclusively, medium-chain acyl-CoA dehydrogenase deficiency (MCADD)is increasingly recognized as a cause of infant death frequently mistaken for SIDS² and as a major cause of sudden death among siblings.³ In testing 4579 blood specimens obtained from autopsies of deaths diagnosed as SIDS, Neo Gen Screening, Inc, of Pittsburgh, Pennsylvania, has identified 21 cases of MCADD as well as 15 cases of other fatty acid oxidation disorders (www.neogenscreening.com/PostmortemScreeningSummary.htm). Retrospective biochemical screening of postmortem liver specimens equally revealed a high incidence of fatty acid oxidation disorders in sudden death cases diagnosed as SIDS.⁴ These deaths from disorders of fatty acid oxidation are preventable by treatment that includes avoidance of fasting, carbohydrate supplementation in the evening, and, perhaps, carnitine.

The critical element in prevention is identification through newborn screening. This is now possible by applying a technology known as tandem mass spectrometry (MS-MS) to the heel-stick blood specimen collected for routine newborn screening.^5,6 Unfortunately, relatively few newborn infants are screened in this comprehensive manner. These include infants born in most (but not all) hospitals in Pennsylvania and, most recently, those born in Massachusetts. The AAP would provide a valuable service by advocating the expansion of newborn screening with MS-MS throughout the United States.

Simone Albers
Harvey L. Levy
Children's Hospital
Boston, MA 02115

REFERENCES

1. American Academy of Pediatrics Task Force on Infant Sleep Position and Sudden Infant Death Syndrome Changing concepts of sudden infant death syndrome: implications for infant sleeping environment and sleep position. Pediatrics. 2000; 105:650-656 [Abstract/Free Full Text]
2. Bennett MJ, Powell S Metabolic disease and sudden, unexpected death in infancy. Hum Pathol. 1994; 25:742-746 [CrossRef][Medline]
3. Iafolla AK, Thompson RJ Jr, Roe CR Medium-chain acyl-coenzyme A dehydrogenase deficiency: clinical course in 120 affected children. J Pediatr. 1994; 124:409-415 [CrossRef][Medline]
4. Boles RG, Buck EA, Blitzer MG, Retrospective biochemical screening of fatty acid oxidation disorders in postmortem livers of 418 cases of sudden death in the first year of life. J Pediatr. 1998; 132:924-933 [CrossRef][Medline]
5. Naylor EW, Chace DH Automated tandem mass spectrometry for mass newborn screening for disorders in fatty acid, organic acid, and amino acid metabolism. J Child Neurol. 1999; 14:S4-S8
6. Chace DH, Hillman SL, Van Hove JL, Naylor EW Rapid diagnosis of MCAD deficiency: quantitatively analysis of octanoylcarnitine and other acylcarnitines in newborn blood spots by tandem mass spectrometry. Clin Chem. 1997; 43:2106-2113 [Abstract/Free Full Text]