Bacteria That Causes Stomach Ulcers: A Culprit in SIDS?

From the WebMD Archives

Oct. 27, 2000 -- Fear of sudden infant death syndrome (SIDS) haunts many parents and other caregivers. Any action that can lower the risk of SIDS receives media attention, such as the "back-to-sleep" movement, after a finding that infants who sleep on their backs are less likely to die of SIDS. New parents often listen for breathing and buy nursery monitors for reassurance.

Now, new research shows that Helicobacter pylori, the bacteria that is known to cause stomach ulcers and may also play a role in heart disease, may play a role in SIDS. In a British study published recently in the journal Archives of Disease in Childhood, investigators examinedtissue samples from 32 infants who had died of SIDS and compared these tissue samples with those from eight infants who had died of other causes. H. pylori genes were present in 28 SIDS cases and just one of the group that died from other causes.

These findings should not cause parents to become alarmed, says study author Jonathan Kerr, MD, or to worry that a parent with an ulcer could give a baby an illness that would result in SIDS. However, he says, the findings do point up the value of appropriate hygiene in the care of infants, such as proper hand washing, particularly before handling bottles and pacifiers. He is a consultant in medical microbiology at the University of Manchester in England.

As many parents and caregivers know, caring for an infant can be exhausting. Pacifiers are always falling out of babies' mouths, particularly in inopportune places, such as playgrounds or shopping malls, where hot water and soap aren't available. While the baby is crying inconsolably -- you guessed it -- the parent gives the pacifier a quick lick in his or her own mouth and puts it right back in the baby's mouth. Any organisms in the parent's mouth, H. pylori in this case, are transmitted through the parent's saliva to the baby.

However, parents should not be unduly alarmed that they are putting their babies at risk of SIDS, says Phipps Cohe, a spokesperson for the SIDS Alliance, a national advocacy group. "While it is not a good idea for parents or caregivers to transfer feeding bottles from their own mouths to their infants for sanitary purposes, alarming the public is unwarranted at this time," Cohe tells WebMD. "This is premature, as the investigators have acknowledged ... the investigators have a long way to go to make this something we can buy as a theory, but we don't want to discourage them from trying."

An H. pylori connection is still preliminary, Kerr agrees. He stresses that although these findings underscore the value of good hygiene in infant care, parents should not be alarmed by the findings, because of the study's preliminary nature. "Although we have found a significant prevalence of H. pylori in SIDS cases versus controls, the numbers are small and [the data] need to be repeated and confirmed independently," he tells WebMD.

The suspicion that H. pylori may play a role in SIDS has been gaining the attention of epidemiologists for some time, though, according to Kerr.

Subsequent studies will show whether H. pylori has a role in SIDS, Bradley Thatch, MD, tells WebMD. "These findings are very preliminary," he says. "Worldwide, many infants get H. pylori, as many as 70% to 80% in developing countries, and most don't die from SIDS. If this bacterium is a factor, it would combine with a number of other risk factors." Thatch, who was not involved in the current research, is a professor of pediatrics at Washington University School of Medicine in St. Louis and served as a co-author of the SIDS Alliance's response to the current research.

Still, "this study is the first confirmatory research that has been published showing the link between H. pylori and SIDS," Philip Pattison, MD, tells WebMD. "The study is excellent. I don't think that H. pylori by itself is enough to explain SIDS across the board. However, it makes the back-to-sleep position all the more urgent, because if an infected infant regurgitates, the material will be more likely to fall back into the esophagus than in the trachea." Pattison, who also was not involved in the current research, is a gastroenterologist and an associate clinical professor of medicine at the University of Missouri in Kansas City. He and his colleagues had conducted the original research that gave rise to the H. pylori hypothesis.