Researchers found the bacterium Klebsiella along with gut inflammation in the intestines of all babies in their study who had colic, a condition characterized by uncontrollable crying.

"We believe that the bacterium may be sparking an inflammatory reaction, causing the gut inflammation," Dr. J. Marc Rhoads, a pediatrics professor at the University of Texas Medical School at Houston and the study's lead investigator, said in a news release from the school. "Inflammation in the gut of colicky infants closely compared to levels in patients with inflammatory bowel disease."

He said colic could possibly lead to other gastrointestinal conditions in later life, such as irritable bowel syndrome and celiac disease.

Colic, which causes an otherwise healthy baby to cry and scream often and for long periods without any noticeable reason, has no medically grounded treatment or known cause, although bottle-fed babies seem to get it more often than breast-fed infants, according to background information in the news release. The condition often disappears as suddenly as it presents itself.

"Colic can be a dangerous situation for a baby," Rhoads said. "The parents' frustration over the crying can lead to maternal frustration, post-partum depression and even thoughts of harming the baby." Half of all infanticides are colic-related, he noted.

The study, published online in the Journal of Pediatrics, included 36 babies, both breast- and bottle-fed. About half had colic. The researchers found that babies without colic had more types of bacteria in their intestines, a sign that certain types of bacteria are beneficial to people, Rhoads said.

He said the researchers plan further study, involving adults as well as infants, on Klebsiella and on whether probiotics, a dietary supplement of so-called good bacteria, could control the gut inflammation in colicky babies.

More information

The American Academy of Family Physicians has more about colic .