Sudden infant death syndrome (SIDS)

Sudden infant death syndrome (SIDS) is a syndrome marked by the symptoms of sudden and unexplained death of an apparently healthy infant aged one month to one year. The term cot death is often used in the United Kingdom, Australia and New Zealand, while crib death is sometimes used in North America. Typically the infant is found dead after having been put to bed, and exhibits no signs of having suffered. SIDS is a diagnosis of exclusion. It can only be applied to an infant whose death is sudden and unexpected, and remains unexplained after the performance of an adequate postmortem investigation including 1. an autopsy;2. investigation of the scene and circumstances of the death;3. exploration of the medical history of the infant and family. SIDS is responsible for roughly 1 death per 2,000 births in the U.S. It is responsible for far fewer deaths than congenital disorders and disorders related to short gestation, though it is the leading cause of death in healthy babies after one month of age. According to the American SIDS Institute, SIDS is "a tragedy which leaves with a sadness and a feeling of vulnerability that lasts throughout their lives." In November 2007, the Bill & Melinda Gates Foundation contributed $11 million to distribute 200,000 cribs in the United States of America to families at-risk of SIDS or in need of financial assistance. Additionally, the grant will fund a study of infant mortality over 100,000 families. The hypothesis of the study is that availability of safe cribs and knowledge of safe sleep practices will reduce the occurrence of SIDS. Very little is certain about the possible causes of SIDS, and there is no proven method for prevention. Although studies have identified risk factors for SIDS, such as putting infants to bed on their stomachs, there has been little understanding of the syndrome's biological cause or causes. The frequency of SIDS appears to be a strong function of infant sex and the age, ethnicity, and the education and socio-economic status of the parents. According to a study published in October 2007 in the Journal of the American Medical Association, babies who die of SIDS have abnormalities in the part of the brain called the medulla oblongata which helps control functions like breathing, blood pressure and arousal. Researchers examined the brains of 31 babies who had died of SIDS and 10 who had died from other causes. It was discovered that the medulla oblongata had neurons that released a chemical called serotonin. The number of these neurons was greater than normal in 55% of the brains of the babies who had died of SIDS. They also found that babies had fewer receptors for serotonin and that abnormalities in the brain stem appear to affect the ability to use and recycle serotonin, which is responsible for regulating mood as well as vital body functions. According to the National Institutes of Health, which funded the study, the new finding is the strongest evidence to date suggesting that innate differences in a specific part of the brain may place some at increased risk of dying from SIDS. In a British study released May 29 2008 researchers discovered that the common bacterial infections Staphylococcus aureus (staph) and Escherichia coli (E. coli) appear to be the cause of some cases of Sudden Infant Death Syndrome. Both the "staph" and E. coli bacteria had a greater presence in the unexplained deaths of infants. SIDS cases peak between eight and ten weeks after birth, which is also the time frame in which the antibodies that were passed along from mother to child are starting to disappear and babies have not yet made their own antibodies. Listed below are several factors associated with increased probability of the syndrome based on information available prior to this recent study.