[Oral tranexamic acid in the treatment of lichen planus pigmentosus: A prospective study of 20 cases]. / Acide tranexamique oral dans le traitement du lichen pigmentogène.

INTRODUCTION: Lichen planus pigmentosus is a variant of lichen planus that is particularly difficult to treat. The aim of this study was to evaluate the efficacy and safety of tranexamic acid in lichen planus pigmentosus. PATIENTS AND METHODS: This prospective study, conducted at the University Hospital of Casablanca from August 2017 to June 2019, included 20 patients with histologically confirmed lichen planus pigmentosus. The exclusion criteria were pregnancy, breastfeeding, known hypersensitivity to tranexamic acid, and thromboembolic disease. Evaluation was carried out by means of clinical examination and measurement of the affected area using the Visioface® RD hardware package at 6 and 12 months (M6 and M12). RESULTS: Eighteen women and 2 men with an average age of 49 years (range: 26-65 years) were included. All patients were phototype 3 or 4. The average disease duration was 2.9 years (range: 2 months-15 years). Pigmented, slate-grey, well-delineated macules were observed in all patients on the face (n=19), neck (n=14) or arms (n=2). Pruritus was present in 9 patients. All patients received oral tranexamic acid 250mg/d for 4 to 6 months with external photoprotection that was prolonged beyond 6 months. At M6, partial improvement was noted in 10 patients, 3 patients showed no improvement, and 7 patients were lost to follow-up. Pruritus disappeared in all patients and no relapse was seen at M12. DISCUSSION: Our study suggests that tranexamic acid could be an effective treatment for lichen planus pigmentosus with a good safety profile. However, the limitations of the study are the limited population and the high number of patients lost to follow-up at M6. Larger-scale studies are needed to provide more detailed results.