Outcomes of Children with Inflammatory Bowel Disease who Develop Anti-tumour Necrosis Factor-induced Skin Reactions

Background and Aims Anti-tumour necrosis factor [anti-TNF] induced skin reactions are common adverse events in paediatric inflammatory bowel disease [IBD]. We aimed to report on outcomes of children with anti-TNF induced skin reactions who switched to ustekinumab [UST] vs. continued anti-TNF therapy. Methods Charts were reviewed for paediatric IBD patients with anti-TNF induced skin reactions. Skin reactions, including psoriasiform dermatitis [PD], were classified as mild or severe based on a severity score. Primary outcome was frequency of skin resolution at 6 months. Secondary outcomes were combined clinical remission and skin resolution at 6 months and skin resolution at latest follow-up. Results A total of 111/638 [17%] children ([85, 21%] infliximab [IFX]; [26, 11%] adalimumab [ADA]) developed skin reactions. Eighty [72%] had PD, 25 [23%] infections, and four [4%] alopecia areata; 71 [64%] continued anti-TNF; and 40 [36%] switched to UST. In all, 73 [66%] had severe reactions and were more likely to switch to UST than if mild (37 [51%] vs. 3 [8%]; p <0.0001). Switching to UST had a higher rate and odds of resolution (29 [73%] vs. 24 [34%]; p <0.0001; odds ratio [OR] = 19.7, 95% confidence interval [CI]: 5.6, 69.5; p <0.0001) and combined remission (21 [52%] vs. 22 [31%]; p = 0.03; OR = 8.5, 95% CI: 2.5, 28.4; p = 0.0005] vs. continuing anti-TNF at 6 months. Conclusions Children who switched to UST after anti-TNF induced skin reactions were more likely to have improved outcomes than those who continued anti-TNF therapy. Future studies are needed to determine immune mechanisms of anti-TNF induced skin reactions and treatment response.