Objectives: Infliximab is used increasingly to treat inflammatory bowel disease (IBD). Infliximab is supplied in 100-mg vials. Doses that are typically calculated as 5 mg · kg⁻¹ · dose⁻¹ are commonly rounded up or down to the nearest 100 mg. Variation in dosing practices is unknown. Underdosing based on weight may increase the risk for disease exacerbation, whereas overimmune suppression could increase the risk of infection. Children may be at greater risk from dosage rounding. We aimed to characterize infliximab dosing practices, the use of corticosteroid premedication, and duration of infusions among pediatric practitioners participating in the ImproveCareNow Network, a national collaboration to improve IBD care and outcomes.
Methods: A national survey of infliximab dosing practices was sent to 279 pediatric IBD practitioners from March to December 2011. Double data reconciliation, t test, and χ² analyses were performed.
Results: The response rate was 74% (N = 207). Thirty-eight percent (78/207) indicated that their practice has no uniform approach to the rounding of doses. Of 114 respondents indicating a uniform approach to rounding doses, 43% always round up to the nearest 100 mg, 33% always round up or down to the nearest 100 mg, and 14% never round doses. In addition, 28% of respondents always premedicate with corticosteroids and 12% never premedicate. Of respondents indicating "it depends," 95% premedicate if there has been a previous infusion reaction, 46% if there has been a prolonged lapse between treatment doses, 40% if antibodies to infliximab are present, and 11% if giving infliximab monotherapy. The duration of infusions is most often 2 hours, but varies between 1 and 4 hours.
Conclusions: Wide variation exists in the practice of infliximab administration in pediatric IBD. The effect of these variations on outcomes is unknown.