(CNN) -- Here's what Katie Roche expected when she went into the hospital for spine surgery: two titanium rods, a bone graft, 17 screws in her vertebrae, eight hours in the operating room, and a week's stay in the hospital to recover. 

Here's what she didn't expect on top of all that: sharing a hospital room with a feverish 6-year-old and contracting a nasty bacterial infection her mother says nearly killed her. 

"She got so weak she couldn't even get out of bed to go to the bathroom -- I had to carry her," says her mother, Kathleen Roche. "For about 48 hours, I didn't think we'd have Katie with us much longer." 

Because of the infection she picked up at the hospital, Katie, who was 19 at the time, dropped from 120 to 90 pounds. 

The bacterium that made her so sick is called Clostridium difficile, and according to a study out this week, it's more common than ever among hospitalized children in the United States, and children who get it are more likely to die or require surgery. 

The study found Clostridium difficile infections in hospitalized children went up 15% per year from 1997, when there were 3,565 infections, to 2006, when there were 7,779 infections. 

The study looked at 10.5 million pediatric patients from 1997 to 2006, of whom 21,274, or 0.2%, had C. diff, as the bacteria are commonly called. The study was published this week in the Archives of Pediatric and Adolescent Medicine. 

"This is huge, and really concerning," says Dr. Peter Pronovost, director of the Quality and Safety research group at Johns Hopkins University. What's really disturbing, he says, is that these children didn't have to get sick. 
Children who get this are likely to die?
The bacterium that made her so sick is called Clostridium difficile, and according to a study out this week, it's more common than ever among hospitalized children in the United States, and children who get it are more likely to die or require surgery.