Azithromycin and metronidazole versus metronidazole-based therapy for the induction of remission in mild to moderate paediatric Crohn's disease : a randomised controlled trial

OBJECTIVE

Crohn's disease (CD) pathogenesis associated with dysbiosis and presence of pathobionts in the lumen, intracellular compartments and epithelial biofilms. Azithromycin is active in all three compartments. Our goal was to evaluate if azithromycin-based therapy can improve response and induce remission compared with metronidazole alone in paediatric CD.

DESIGN

This blinded randomised controlled trial allocated children 5-18 years with 10<Pediatric Crohn's Disease Activity Index (PCDAI)≤40 to azithromycin 7.5 mg/kg, 5 days/week for 4 weeks and 3 days/week for another 4 weeks with metronidazole 20 mg/kg/day (group 1) or metronidazole alone (group 2), daily for 8 weeks. Failures from group 2 were offered azithromycin as open label. The primary end point was response defined by a decrease in PCDAI>12.5 or remission using intention to treat analysis.

RESULTS

73 patients (mean age 13.8±3.1 years) were enrolled, 35 to group 1 and 38 to group 2. Response and remission rates at week 8 were identical 23/35 (66%) in group 1 and 17/38 (45%) and 15/38 (39%) in group 2 (P=0.07 and P=0.025, respectively). The needed to treat for remission was 3.7. Faecal calprotectin declined significantly in group 1 (P=0.003) but not in group 2 (p=0.33), and was lower at week 8 (P=0.052). Additional therapy was required in 6/35(17%) from group 1 versus 16/38(42%) in group 2 (P=0.027) by week 8. Among 12 failures in group 2, open-label azithromycin led to remission in 10/12 (83%).

CONCLUSIONS

The combination of azithromycin and metronidazole failed to improve response but was superior for induction of remission and reduction in calprotectin.

TRIAL REGISTRATION NUMBER

NCT01596894.

Limitations of fecal calprotectin at diagnosis in untreated pediatric Crohn's disease

BACKGROUND

Fecal Calprotectin (FC) is a validated screening test for intestinal inflammation in Crohn's disease (CD). The objective of the study was to prospectively evaluate the limitations of FC for identifying CD in newly diagnosed untreated pediatric patients and to assess the association of FC levels with disease location and serum inflammatory markers.

METHODS

Consecutive children with new onset untreated CD participating in the ongoing ESPGHAN GROWTH CD study were evaluated at diagnosis for disease activity, extent, C-reactive protein (CRP), and FC.

RESULTS

In all, 60 children met the inclusion criteria (mean age 12.6 ± 4.6 years,), 25 (42%) with mild disease, 17 (28%) moderate disease, and 18 (30%) severe disease. Twenty-seven (45%) had small bowel disease only. Median FC levels did not differ between children with small bowel only (2198 μg/g interquartile range [IQR] 696-2400) and those with colonic involvement (with or without small bowel disease; 2400 μg/g (IQR 475-2400) (P = 0.76). FC was elevated in 95% of patients, in comparison to CRP (86%) and erythrocyte sedimentation rate (ESR) (83%). Three children (5%) who had normal calprotectin levels also had low or normal CRP and/or ESR. There was no correlation between calprotectin levels and either the pediatric CD activity index (r = -0.11; P = 0.94) or physicians global assessment.

CONCLUSIONS

FC levels in active disease confined to the small bowel were elevated in the vast majority of children and site of disease was not a confounding factor in this setting. Patients with low FC had a trend toward low levels of inflammatory markers as well. We did not find a significant correlation between FC and clinical indices of activity.