P38 Evaluating compliance to thiopurine monitoring guidelines in paediatric inflammatory bowel disease
Authors: Treadwell Maria , Patel Shiras 
Published: April 2023

Aim

Paediatric inflammatory bowel disease (IBD) accounts for 7–22% of IBD cases globally and there is evidence to suggest that the incidence is rising.1The aims of therapy in paediatric IBD are to relieve symptoms, optimize growth, improve quality of life while minimizing drug toxicity and reducing the risk of complications without surgery. Treatment involves two main steps, inducing remission and maintaining remission. Thiopurines are effective at maintaining remission in IBD but have serious adverse effects, such as myelosuppression and hepatotoxicity,2therefore, patients on thiopurines must have regular monitoring to ensure safe prescribing. Several national and international guidelines have been created recommending monitoring parameters for patients on thiopurines. At our trust we follow the British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN) guidelines.3The primary aim of this study was to evaluate compliance to the BSPGHAN guidelines for initiating and monitoring paediatric IBD patients on thiopurines at a tertiary paediatric gastroenterology unit.

Method

Paediatric patients on thiopurines were identified using the pharmacy dispensing system. Subsequently, patient electronic records were accessed to collect demographics and data comparing compliance to the BSPGHAN guideline. The BSPGHAN guidelines state that patients should have a thiopurine methyl transferase screen, FBC, LFT and documented counselling before initiating thiopurines, with subsequent FBC, LFT and metabolite monitoring at specific frequencies while on maintenance therapy. Data analysis was performed in two ways. Firstly, overall guideline compliance was assessed by examining compliance with each guideline criterion. Secondly, percentage compliance scores were generated for each patient to assess the variation in guideline compliance between patients. The Mann-Whitney U test compared percentage compliance scores between the sexes and thiopurine used while the Kruskal-Wallis test compared percentage compliance scores between IBD phenotypes.

Results

Compliance to all guideline criteria were less than 100%. Percentage compliance scores ranged from 44.4% to 100%, with a median of 88.9% and interquartile range of 77.8% to 100%. Compliance was generally higher for the monitoring undertaken at initiation of treatment, with the lowest level of compliance score of 61% seen for the monitoring requirements at the 12-week interval post initiation of treatment. Only 56 patients (37.3%) had a percentage compliance score of 100%. Statistical difference was not observed in percentage compliance scores between sex, thiopurine used and IBD phenotype.

Conclusion

Suboptimal guideline compliance was noted at the trust, suggesting improvements need to be made to comply with recommended monitoring requirements for thiopurines. The results suggest consideration of using a more simplified regimen for routine monitoring should be considered, such as that recommended by the British National Formulary (BNF). The variation in percentage compliance scores between patients warrants further investigation to identify possible causes for this variation.

References

Auvin S, Molinié F, Gower-Rousseau C, Brazier F, Merle V, Grandbastien B,et al. Incidence, clinical presentation and location at diagnosis of paediatric inflammatory bowel disease: a prospective population-based study in Northern France (1988–1999).Journal of Paediatric Gastroenterology and Nutrition[Online] Lippincott Williams and Wilkins; 2005;41(1):49–55. Available from: doi:10.1097/01.MPG.0000162479.74277.86

British National Formulary. Azathioprine [Online]. Available from https://bnfc.nice.org.uk/drugs/azathioprine/ [Accessed May 2022]

BSPGHAN IBD Working group [Online]. Thiopurine (Azathioprine/Mercaptopurine) Blood Monitoring Guidelines. 2018. Available from https://bspghan.org.uk.

[Accessed January 2022]