168
were receiving concomitant mercaptopurine. A larger single-center retrospective
series by McGinnis et al. evaluated the short- and long-term response to infliximab
induction in 40 pediatric UC patients with steroid-dependent or steroid-resistant
disease [ 22 ]. Twenty-eight patients (70%) had a clinical response to infliximab,
including 9 of 12 patients with steroid-dependent disease and 18 or 27 with steroid-
refractory disease. Over the study period, 20% of responders had undergone colec-
tomy compared to 82% of nonresponders. A multicenter cohort, inception cohort
study of 332 pediatric patients with UC prospectively evaluated outcomes of 52
patients who received continuous maintenance therapy or episodic treatment with
infliximab [ 23 ]. Approximately 35% of these patients had corticosteroid-free inac-
tive or mild disease at 3-, 6-, 12-, and 24-month assessments, and 61% were
colectomy- free at 24 months. Looking at the subset of patients receiving continuous
maintenance therapy, approximately 50% of the patients had inactive or mild dis-
ease across these time points, and the likelihood of being colectomy-free was 74%
at 24 months, suggesting additional benefit on maintenance dosing. These remission
rates were lower than previously reported; however, 50% of this cohort was hospi-
talized at initiation of infliximab, perhaps suggesting more severe or chronic
disease.
Patients with chronic ulcerative colitis refractory to treatment with steroids,
immunomodulators, and aminosalicylates may have decreased response to inflix-
imab therapy. Fanjiang et al. retrospectively evaluated response to infliximab in
acute UC (n = 16), defined as new-onset UC that was refractory to intravenous ste-
roid therapy or an acute exacerbation of nonsteroid-dependent UC, compared to
response in chronic, steroid-dependent UC (n = 11) [ 24 ]. Patients received standard
induction dosing followed by every 8-week infusions. Patients with acute UC had
lower-average Lichtiger colitis activity index (LCAI) scores at 1 and 2 months after
therapy and more durable long term response. Over a mean follow-up of 27 months,
75% of patients with acute UC did not require steroid therapy or colectomy com-
pared to 27% of chronic UC patients.
Based on retrospective analysis of a population-based UC cohort, 28% of chil-
dren <15 years old require hospitalization for an acute severe exacerbation of their
disease, and almost 50% these patients are refractory to intravenous corticosteroids
[ 25 ]. As demonstrated by colectomy rate in the study by Fanjiang et al. [ 24 ], there
is some evidence that patients presenting with acute, fulminant, severe colitis may
have an improved response to treatment with infliximab compared to those with
chronic, steroid-dependent colitis. In a prospective, multicenter study of 128 chil-
dren with acute, severe colitis requiring intravenous corticosteroid therapy, 37
patients (29%) failed to respond to corticosteroids and required rescue therapy, 33
of whom receive infliximab [ 26 ]. Twenty-five (75%) of these patients responded,
with 7 patients entering clinical remission and 18 patients being discharged with
mild disease severity. At 1 year, 55% of these patients had sustained response (11
receiving maintenance therapy and 7 receiving only induction therapy). Patients
with newly diagnosed with UC, shorter duration of disease, and more severe disease
activity at admission and after 3 days of IV steroid treatment were less likely to
respond to infliximab. A smaller respective cohort of 29 hospitalized patients with a
S. Patel and J. Strople