A Case Report of Pirfenidone-Induced Lichenoid Drug Eruption in a Patient with Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and lethal lung disease characterized by progressive dyspnea and irreversible loss of lung function. Pirfenidone is a novel anti-fibrotic and anti-inflammatory drug, which reduces deterioration in the lung function and prolongs progression-free survival in patients with IPF. However, it has adverse effects including gastrointestinal symptoms, hepatic dysfunction or skin photosensitivity, and rash. Lichenoid drug eruption (LDE) refers to lichen planus-like drug eruption usually presenting symmetric eczematous plaques with a purple hue. To date, numerous cases of LDE due to various drugs and pirfenidone-associated photosensitivity have been reported. However, a case of pirfenidone-induced LDE has been very rarely reported to our knowledge. Herein, is a case of pirfenidone-induced LDE so that clinicians can be aware of the possibility of LDE when using pirfenidone.