P172 Immunisation and vaccination status at diagnosis in Pediatric inflammatory bowel disease

Abstract

Background Pediatric inflammatory bowel disease (PIBD) patients are especially prone to vaccine-preventable diseases and opportunistic infections. The aim was to evaluate the immunisation and vaccination status in PIBD. Methods Descriptive and retrospective study that analyses the immunisation and/or vaccination for measles, mumps and rubella (MMR), hepatitis B virus (HBV), chickenpox, cytomegalovirus (CMV) and Epstein–Barr virus (EBV) of PIBD patients in a tertiary paediatric hospital (January 2015- Oct 2019) in the first 6 months after diagnosis. Results Amongst 57 patients, 17 (30%) had ulcerative colitis (UC), 35 (61%) Crohn’s disease (CD) and 5 (9%) unclassified IBD (uIBD). Up to 35 (61%) were male and the mean age at diagnosis was 10.2 ± 4.1 years. A total of 18 (32%) were currently on biological treatment and 45 (79%) on immunosuppressants. The disease location in CD patients was L3 (Paris classification) in 22 (63%) and L4a in 13 (37%). Only 2 (6%) showed perianal involvement. From the UC patients, 11 (65%) were E4. A delayed growth was observed in 6 (10%), all CD patients. At diagnosis, 37 (65%) were HBV-vaccinated, 13 of them (35%) had a serological response and 22 (59%) had no response. Amongst the latter, 18 were re-vaccinated and 9 (50%) had a documented serological response. Up to 34 patients (60%) were MMR-vaccinated and 13 (38%) showed a complete response. Only 6 patients could be re-vaccinated. Up to 30 (52%) showed chickenpox immunisation. Only 4 of the non-immunised patients could be vaccinated and all of them responded to a single dose. Regarding CMV and EBV, 17 and 16 patients (46 and 43%) were IgG positive respectively, all of them were IgM negative. Patients with CD were more likely to need HBV re-vaccination than other IBDs (p < 0.05). Regarding chickenpox, CD patients without growth delay (G0) needed less re-vaccination than those whose growth was affected (G1) (p < 0.05). However, UC patients with extensive disease (E4) needed less re-vaccination than those with limited disease (p < 0.05). Male patients seemed to be less likely to need re-vaccination, with no significant differences. Conclusion The serological assessment of vaccine-preventable diseases immunisation yielded poor results. Remarkably, a high percentage of HBV and MMR vaccinated patients showed no response. CD patients tended to more likely need revaccination, especially in the most severe cases (G1). Surprisingly, severity was not related with vaccination response in UC. Our results suggest that less than half of the patients had been previously infected by CMV or EBV. Based on this, it seems reasonable to serologically check the immunisation status in PIBD patients in order to, when appropriate, re-vaccinate before starting immunosuppressive therapies.