Cases of Clostridium difficile-associated disease at children's hospitals increased significantly between 2001 and 2006, but in-hospital mortality and colectomy rates did not increase during that time, in what the authors say is the first study to report “the increasing nationwide burden” of C. difficile-associated disease at freestanding pediatric hospitals.
A significant increase in the use of oral metronidazole to treat C. difficile-associated disease (CDAD) and the preponderance of cases in children with complex medical conditions were among the other notable findings of the retrospective cohort study, conducted at 22 children's hospitals across the United States, according to Dr. Jason Kim of the division of infectious diseases at Children's Hospital of Philadelphia, and his associates (Pediatrics 2008;122:1266-70).
They pointed out that, while the incidence and severity of CDAD in adults had been increasing, the epidemiology of CDAD in the pediatric population has “remained relatively undefined.”
Previous studies were usually done in one center, and provided inconsistent results. But this study was a multicenter trial and documented the largest number of pediatric CDAD cases reported—4,895 cases among children under age 18 years, they said.
The median age of these children was 4 years; CDAD was defined as a hospitalized child with a discharge code for C. difficile infection, a laboratory billing charge for C. difficile toxin assay, and an initial dose of CDAD antimicrobial therapy (oral or parenteral administration of metronidazole or oral vancomycin).
Of the cases, 54% were boys, 76% were white, 26% were aged 1 year or younger, and 5% were under 1 month of age. Most (67%) had at least one complex underlying medical condition, which among children 1 month and younger was most often a cardiovascular condition; a malignancy was the most common condition among the oldest children.
Between 2001 and 2006, the annual rate of CDAD increased from 2.6 to 4.0 cases per 1,000 admissions, a 53% increase. No regional differences in CDAD incidence were detected.
When they analyzed age groups separately, the authors found a marked increase in cases among children ages 1-5 years, from 0.7 to 1.3 cases per 1,000 admissions, an 85% increase. There were increases from 1.2 to 1.8 cases per 1,000 admissions among children ages 5-17 years. But there was no significant difference in the CDAD incidence among children under age 1 year.
Single therapy of oral metronidazole was the most common treatment (61%), use of which increased significantly over the period studied. The use of oral vancomycin, which was used to treat 3.5% of the children, did not increase during the study.
During the period studied, 61 of the children underwent a colectomy, at a median age of 2.1 years, but the rate did not increase during the study.
All-cause mortality among the children with CDAD was 4%, and did not increase, unlike the increase that has been documented in adults, they observed.
The increase in CDAD cases in the hospitalized children could be attributable to more people carrying C. difficile, or to an increase in the more virulent strain of C. difficile, the North American pulsed-field gel electrophoresis type 1 (NAP1), which “is considered a major factor for the recent increase in adults,” Dr. Kim and his associates wrote.
The researchers pointed out that 26% of the cases occurred in children under age 1 year and 5% under age 1 month—a significant proportion of whom “were at an age previously thought to be unaffected by C. difficile toxin.”