P645 Use of Leukocytapheresis in inflammatory bowel disease in paediatric patients. A serie of 10 cases.
Authors: Martinez Navarro G , Palomino Pérez L M , Velasco Rodríguez-Belvís M , Cañedo Villarroya E , De la Mano Hernández A , Dominguez Ortega G , Martínez Pérez J , Martín Fernández C , Di Campli Zaghlul M , García Hernández P , Sánchez Llorente P , Muñoz Codoceo R A 
Published: January 2023

Abstract

Background
Inflammatory bowel disease causes increased granulocyte and monocyte activation. Leukocytapheresis (LCA) is a safe technique that has shown efficacy in ulcerative colitis wich replaces activated leukocytes decreasing the cytokines involved in inflammatory response.
The objective of this report is to describe the main characteristics of patients in whom LCA was made and evaluate the response to different types of LCA.

Methods
A descriptive and retrospective study that analyses clinical and analytical data of patients diagnosed with IBD who underwent LCA a cause of refractory to conventional treatment, in a tertiary paediatric hospital between 2006 and 2022.
The following variables were studied: Demographic data, treatments before and during LCA, reason for the onset of LCA, clinical and analytical situation, characteristics of the sessions, beneficial and side effects.

Results
10 patients (3 women and 7 men) diagnosed with ulcerative colitis (E4S1) were included. The mean age at diagnosis was 11,6 +/- 1,9 years. 6 patients received combination therapy (biologic + inmunomodulator), 2 immunomodulator in monotherapy, 1 biologic in monotherapy and 1 neither immunomodulator nor biologic.
14 cycles were analyzed during a median follow-up of 37 +/- 31 months. The main indication to initiate LCA was steroid-dependence (55%). The rest of indication: Steroid-refractoriness (15%), primary non response to biologics (15%) and secondary loss of response to biologics (15%). The mean age at the start of LCA was 14,1 +/- 1,8 years. In 78% corticotherapy was added. The average duration was 93 +/- 84 days with a mean of 8,6 +/- 4,5 sessions. 1 adverse effects were reported: Transient hypertransaminasemia. The effect of the therapy was beneficial in 71% and corticotherapy could be withdrawn &gt; 3 months in 9 instances; in 2 of them &gt; 12 months. In addition, 1 patient continued his treatment with Infliximab despite primary failure and 1 patient recovered from the secondary loss of response to Adalimumab. 4 of 7 patients had to switch to a different biologic agent. Average decrease in the PUCAI score of 33 +/- 30 points was observed as and average decrease in the values of leukocytes, neutrophils, lymphocytes and monocytes of 1,8 +/- 5,2 × 109/L, 1,9 +/- 5,1 × 109/L, 0,1 +/- ,1 × 109/L and 0,2 +/- 0,3 × 109/L and a decrease in the CRP, ESR and FC of 4,8+/- 10,6 mg/dL, 4,1 +/- 36,3 mm/h and 536 +/- 977 mcg/g. LCA was more effective when the indication was corticodependence versus other indications (p&lt;0,05). No significant differences were found in the subgroup analyisis.

Conclusion
In our experience, LCA has proven to be a safe and effective treatment in more than 50% of paediatric patients with refractory CU, especially in corticodependent patients.