A 5-year retrospective study on the outcome of patients with acne vulgaris treated with oral isotretinoin in Ipoh Hospital

ABSTRACT

Objective The purpose of this study is to determine the outcome of patients with acne vulgaris treated with oral isotretinoin from January 2003 till January 2008. Methodology This is a 5-year retrospective study of patients with acne vulgaris who were started on oral isotretinoin from January 2003 to January 2008. Only patients who have completed at least 4 months of treatment were included. Case notes were retrieved and analyzed with regards to demographic data, total cumulative dose of oral isotretinoin, duration of treatment, average daily dose of isotretinoin, response, relapse and subsequent treatment. Patients who defaulted follow-up were contacted via phone to ascertain if they had any relapse. Laboratory data that were analyzed included serial liver enzymes, total cholesterol, triglyceride and LDL levels. Results A total of 110 case notes were reviewed but only 83 patients fulfilled the inclusion and exclusion criteria. Average daily dose of isotretinoin was 0.24 mg /kg/day and mean duration of treatment was 9.56 months. Mean total accumulated dose of isotretinoin was 61.96 ± 34.15 mg/kg (range from 11.18 mg/kg to 151.79mg/kg). There were only 6 (7.2%) patients who achieved total accumulated dose of more than 120mg/kg/day. All of our patients responded to treatment with 24 (28.9%) of them were in complete clearance. However, a high percentage (71.2%) of patients developed mucocutaneous side-effects out of which 27.7% required dose reduction. Relapse rate among those who completed treatment and follow up or contactable for at least 6 months post treatment was 24.2% (8 out of 33 patients). There were only 3 (3.6%) patients who developed raised transaminases during treatment but all were less than twice the upper normal limit. Mean total cholesterol, triglyceride and LDL level were significantly raised at 4 months of treatment when compared to the baseline (p<0.05). Conclusion Low dose Isotretinoin (<0.5mg/kg) is an effective treatment for moderate to severe acne vulgaris in our population. All of our patients showed good response to isotretinoin even though some of them relapsed subsequently. Intolerability as a result of mucocutaneous side-effects seems to be a challenging issue when starting isotretinoin in our population.