LAUSR

Dear Editor, Atopic dermatitis (AD) is very common and can affect up to 20% of children. Poorly controlled AD can lead to poor quality of life for the child and family. Severe AD patients may be refractory to topical therapies and require phototherapy or systemic immunosuppressants. We performed a retrospective analysis of a cohort of Asian children and adolescents with moderate or severe AD treated with systemic immunosuppressants at our tertiary pediatric dermatology unit. We performed a retrospective, observational review of all patients aged <16 years with a clinical diagnosis of AD (Hanifin and Rajka criteria), treated with ciclosporin, azathioprine or methotrexate, between January 2012 and August 2017 at KK Women's and Children's Hospital. Approval was obtained from the Centralized Institutional Review Board (CIRB). Patients' case records were reviewed, and information recorded included demographic data, clinical and treatment history, dosage and duration of treatment, investigations and side effects. Response to treatment was graded by individual patients' pediatric dermatologists, and the maximal change from baseline after starting on immunosuppressants was recorded for this study. Response to treatment was classified as good if there was more than 50% improvement, moderate if there was between 25% and 50% improvement and poor if there was less than 25% improvement. Thirty-five patients were identified, with 21 males and 14 females, with a median age of 10 years (range: 5-15 years). There were 27 Chinese (78%), seven Malays (19%) and one Indian (3%) patient. The median duration of AD prior to starting immunosuppressants was 8 years. The patient characteristics and treatment response are summarized in Table 1. There were 27 patients (77.1%) treated with ciclosporin, 14 patients (40.0%) with azathioprine and 11 patients (31.4%) with methotrexate. Nine patients were treated on separate times with two immunosuppressants, and four patients with all three agents. The median age of commencing treatment with ciclosporin was 10 years (range: 5-15 years), the median maximal dose was 3.6 mg/kg/d (2.6-4.5 mg/kg/d) and median duration of treatment was 35 weeks (5-133 weeks). The median age of treatment with azathioprine was 8 years (5-13 years) at median maximal dose of 1.6 mg/kg/d (0.9-3.2 mg/kg/d) and median duration of 50 weeks (2-122 weeks). The median age of treatment with methotrexate was 12 years (5-14 years) at median dose of 0.3 mg/kg/wk (0.1-0.5 mg/kg/wk) and median duration of 38.5 weeks (2-123 weeks). The percentage of patients who achieved moderate or good response was 51.9% (14/27) for ciclosporin, 64.3% (9/14) for azathioprine and 45.4% (5/11) for methotrexate. Two patients discontinued ciclosporin due to side effects (one hypertension and one gingival hyperplasia). There were marginal increases in serum creatinine levels for two patients on cyclosporine, but these eventually normalized upon dose adjustment. No patients on azathioprine or methotrexate discontinued treatment due to side effects, although two patients on azathioprine developed mildly elevated serum transaminases and one patient developed nausea on methotrexate. Our retrospective study has shown that ciclosporin, azathioprine and methotrexate have similar moderate efficacy in the treatment of Asian children with moderate or severe AD. However, the response rates in our cohort of patients appears less favorable compared to other studies conducted in different races. This may be