Immunisation status of children and adolescents with a new diagnosis of inflammatory bowel disease.

BACKGROUND: Patients with Inflammatory Bowel Disease (IBD) are at increased risk of serious infections, including vaccine preventable diseases. Current evidence suggests uptake of additional recommended special risk vaccinations is low. Identification of IBD patients prior to commencing immunosuppressive therapy allows for optimisation of vaccination, including timely administration of live-attenuated and additional recommended vaccines, such as influenza and pneumococcal vaccines. METHODS: Paediatric patients (0-18 years) seen at the tertiary Royal Children's Hospital, Melbourne, Australia, with a recent diagnosis of IBD were referred by the Gastroenterology Unit to our Specialist Immunisation Clinic (SIC) for assessment and provision of routine and special risk vaccines. Data was collected via a standardised REDCap questionnaire completed in or post attendance at the SIC and included serology results where available. RESULTS: Sixty-nine paediatric patients were recruited to the study between 2014 and 2017. Median age at IBD diagnosis was 11.25 years (IQR 4.64 years), with median time between diagnosis and SIC review of 0.88 years (IQR 2.84 years). At initial review 84.1% (58/69) of patients were up to date with vaccines on the Australian National Immunisation Program (NIP) schedule. Of those who were tested, serological evidence of immunity was demonstrated in 38.3% (23/60) of patients for Hepatitis B, 66.7% (36/54) for measles, 51.9% (28/54) for rubella and 41.9% (26/62) for Varicella Zoster Virus. Prior to SIC review 47.8% (33/69) had additional vaccinations and 92.8% (64/69) had vaccinations administered in the 12 months following SIC assessment. The Pneumococcal conjugate vaccine (76.8%, 53/69) was the most commonly administered vaccine after SIC review, followed by influenza vaccine (69.6%, 48/69). Within 12 months of SIC review 43.5% (30/69) of patients had completed the schedule and were up-to-date as recommended by the SIC. CONCLUSIONS: Children with IBD and other special risk groups can benefit from early referral to a SIC team to ensure optimal administration of routine and additionally recommended vaccines, especially live and additional special risk vaccines. The value of optimising immunisations could also be applied to other special risk groups, including adult IBD cohorts, particularly those commencing newer biologic immunosuppressive medications.