The adverse effect profile of oral azathioprine in pediatric atopic dermatitis, and recommendations for monitoring
Presented orally at British Society of Pediatric Dermatology at the British Association of Dermatologists, Liverpool, UK, July 2013 meeting and as a poster at the World Congress of Pediatric Dermatology, Madrid, Spain, September 2013.
Azathioprine is efficacious in the treatment of severe childhood atopic dermatitis; however, robust data on adverse effects in this population are lacking.
Objective
We sought to assess adverse effects of azathioprine treatment in a pediatric atopic dermatitis cohort, and make recommendations for monitoring based on these data.
Methods
Blood test results for all 82 children prescribed oral azathioprine for atopic dermatitis in our department between 2010 and 2012 were collated prospectively, and clinical notes were reviewed retrospectively.
Results
Mean age at commencing azathioprine was 8.3 years (SEM 0.4). Mean maximum doses were 2.4 mg/kg (SEM 0.1) and 1.5 mg/kg (SEM 0.1) for normal and reduced serum thiopurine-S-methyltransferase levels, respectively. Adverse effects on blood indices occurred in 34 of 82 patients (41%), with pronounced effects in 18 of 82 (22%) after a median time of 0.4 years. Two patients stopped therapy as a result of abnormal blood indices. Clinical adverse effects occurred in 16 of 82 (20%), two resulting in cessation of therapy. Incidence of adverse effects was unaffected by age, sex, thiopurine-S-methyltransferase level, and drug dose on multivariate regression.
Limitations
Comparison with other studies is limited by varying definitions of adverse effects.
Conclusion
Oral azathioprine was associated with few pronounced adverse effects for the duration of use and dosage in this cohort. Recommendations for monitoring are made.
Key words
atopic dermatitis
azathioprine
child
eczema
guidelines
monitoring
pediatric
safety
systemic
therapy
Abbreviations used
AD
atopic dermatitis
CBC
complete blood cell count
TPMT
thiopurine-S-methyltransferase
Cited by (0)
Dr Kinsler was funded by the Livingstone Skin Research Center, UCL Institute of Child Health, London.