Understanding Paradoxical Psoriasiform Dermatitis (PD) in Children on TNF inhibitors: A Deep dive for Parents & Providers
Paradoxical psoriasiform dermatitis (PD) is a challenging skin reaction that can occur in children receiving tumor necrosis factor inhibitors (TNFi) – medications commonly used to treat conditions like Crohn’s disease, juvenile idiopathic arthritis (JIA), and ulcerative colitis. While TNFi therapies are life-changing for many, understanding PD – it’s causes, how it presents, and what to do about it – is crucial. This article breaks down the latest research, offering insights for both parents and healthcare professionals.What is Paradoxical Psoriasiform Dermatitis?
Essentially, PD is a skin rash that looks like psoriasis, but develops during treatment with a medication designed to suppress the immune system. It’s considered “paradoxical” as the medication should, in theory, be reducing inflammation, not triggering a psoriasis-like eruption. It’s vital to remember this isn’t a typical allergic reaction; it’s a more complex immune response.Recent Research: What we now Know
A recent retrospective chart review from Cincinnati Children’s Hospital Medical Center, analyzing data from over 3400 young patients on TNFi therapy, shed valuable light on this condition. Here’s a breakdown of the key findings:
Incidence: Approximately 2% of children on TNFi developed PD.
Demographics: PD was more common in girls (52.9%) and among White patients (91.4%). The median age at the start of TNFi was 11.7 years, with PD typically appearing around age 13.6.
Concomitant Medications Matter: Interestingly, the use of other immunomodulating medications alongside TNFi was associated with a delayed onset of PD.
Widespread Rash: In over 90% of cases, the PD rash appeared in multiple locations on the body.
Time to Resolution: While the rash eventually resolved in about 46% of patients, it took a median of 15.5 months.
What Factors Increase the Risk of PD?
The study identified several potential predictors for developing PD, or experiencing a later onset:
JIA Diagnosis: Children with JIA were found to have a later onset of PD, by an average of 22.6 months.
Older Age at Treatment Start: Starting TNFi therapy at an older age correlated with a later PD onset (an average of 2.4 months delay per year of age). Immunomodulator Use: Using other immunomodulating drugs with TNFi also delayed the onset of PD (by an average of 11 months).
Gender: While not definitively proven, the research suggests girls may experience more severe PD, potentially due to differences in treatment approaches or underlying disease severity. Further research is needed.
How is PD Treated?
Treatment approaches vary depending on the severity of the rash. Common strategies include:
Topical Steroids (85.7%): These are the first-line treatment for many cases. Girls were more likely to receive high-potency steroids, wich warrants further investigation.
Non-Steroidal Topicals (24.3%): Medications like tacrolimus,pimecrolimus,and calcipotriene can be used as alternatives or adjuncts to steroids.
Systemic Medications (15.4%): In more severe cases, medications taken by mouth or injection may be necessary.
What Happens When PD Develops? Impact on Treatment
Managing PD can be complex. Here’s what the research revealed about treatment adjustments:
Discontinuation of TNFi: Over half (57.1%) of patients had their initial TNFi stopped due to PD.
Switching Medications: of those who stopped their initial TNFi:
30% switched to another TNFi, but experienced a 33% recurrence rate of PD.
62.5% switched to a different class of medication, but PD persisted in 36% of those patients.
This highlights the importance of careful consideration and shared decision-making when managing PD and its impact on yoru child’s overall treatment