Suboptimal Vaccination Coverage and Serological Screening in Western Australian Children With Inflammatory Bowel Disease Receiving Immunosuppressive Therapy: An Opportunity for Improvement.

Background Patients with inflammatory bowel disease (IBD) face an increased likelihood of severe illnesses, including those caused by vaccine-preventable diseases. Consequently, the purpose of this study was to evaluate both vaccination rates and serological screening in children with IBD in Western Australia, focusing on compliance with routine and additional vaccines, and pre-treatment screening for infections before starting immunosuppressive (IS) treatment. Method The study was conducted at Perth Children's Hospital (PCH) from June 2021 to February 2022, focusing on children aged 0-18 with confirmed IBD diagnoses. Demographic and medical data were collected and matched with immunization records from the Australian Immunisation Register (AIR) to audit compliance with routine childhood vaccinations and additional vaccines (23-valent pneumococcal, human papillomavirus (HPV), and annual influenza). Data from medical records were analyzed for compliance with serologic testing (QuantiFERON TB, Hep B and C, Varicella, and Epstein-Barr virus (EBV)) before initiating IS therapy, which included immunomodulators, biologics, or small molecules. Results Of the 243 patients, 120 (52%) were diagnosed with Crohn's disease and 106 (43%) with ulcerative colitis. A total of 181 patients (74.5%) were treated with immunomodulators, while 62 (26%) received biologic therapies. Incomplete routine vaccination coverage was identified in 71 (29.2%) patients, with no notable differences observed between the IS and non-IS groups (p=0.3). Specific vaccines with incomplete coverage included HPV in 49 (24%) patients, Varicella in 39 (16%) patients, and diphtheria-tetanus-pertussis (DTP in 16 (6.5%) patients. Pre-treatment serological screening was also suboptimal, with the lowest testing rate for EBV at 32 (13.2) patients and the highest for Varicella at 181 (74.6%) patients. Conclusion The results emphasized the importance of targeted interventions to enhance vaccination and screening practices, enhancing disease management, and reducing the possibility of preventable infections in the vulnerable populace.