(219) Short course cefixime for the prevention of irinotecan-associated diarrhea in children with solid tumors

Poster Abstract:

Background: Prophylactic oral third generation cephalosporins, administered prior to and concurrently with irinotecan reduces dose-limiting diarrhea and allows higher irinotecan dosing in pediatric patients. Currently, the Children’s Oncology Group (COG) recommends a 10-day regimen of cefixime starting 2 days prior to each 5-day irinotecan course. However, an analysis of prescribing practices at our institution identified poor adherence to these recommendations with only 7% of courses having received 2 days of prophylaxis before initiating a course of irinotecan and 71% of courses receiving >10 days of prophylaxis. To standardize prescribing patterns and limit antibiotic exposure, a multidisciplinary team implemented a short-course 5-day prophylactic regimen of cefixime administered only on days irinotecan was administered. It is our hypothesis that shortening the course of cefixime did not increase the incidence of severe diarrhea and reduced inappropriate antimicrobial exposure.

Objectives: The primary objective of this study was to compare the incidence of severe diarrhea with the first course of irinotecan before and after the implementation of short-course cefixime prophylaxis. Secondary objectives include evaluation of provider adherence and total duration of antibiotics administered per course of irinotecan as well as the incidence of Clostridioides difficile or other opportunistic or ceftriaxone-resistant infections.

Methods: In January 2020, St. Jude Children’s Research Hospital implemented short-course cefixime prophylaxis for the prevention of irinotecan-induced diarrhea. This is a single-center, retrospective chart review of all patients who received a 5-day course of irinotecan for the 12 months before and 18 months after the intervention. In addition to general demographic information, the following information was collected regarding the patient’s first course of irinotecan: irinotecan initiation and stop date, third generation cephalosporin initiation and stop date, intensive care unit admission for consequences of uncontrolled diarrhea and/or dehydration, delay of next course and subsequent reasoning, presence of Clostridium difficile colitis or Gram-negative bacterial infections. Severe diarrhea was defined as the need for the following interventions related to diarrhea: hospitalization, intravenous fluid support, or total parenteral nutrition support. Inferential statistics were used to compare the incidence of severe irinotecan-associated diarrhea pre- and post-implementation.

Results: pending

Conclusions: pending

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