Dear Editor, A 16-year-old boy, known to have Juvenile Idiopathic Arthritis–extended oligo-articular (JIA), presented with a pustule over the left leg rapidly progressing to a large, exceedingly painful ulcer. On examination he had pallor, flexion deformity of right elbow and active arthritis of both wrists. An ulcer measuring 10×5 cm was there over left shin with central necrosis and undermined erythematous edges (Fig. 1a). A diagnosis of pyoderma gangrenosum (PG) was made and a biopsy from ulcer margin was consistent with this diagnosis. There was no evidence of malignancy or infection. He was initiated on oral prednisolone (1 mg/kg/day), methotrexate (10 mg/week) and topical tacrolimus (0.03% w/w) twice a day under occlusive dressing. After 3 weeks, the ulcer had significantly healed with complete resolution of pain (Fig. 1b). PG is a rare and a serious ulcerating disease of the skin of unknown cause [1]. Abnormal neutrophil chemotaxis has been implicated [2]. Affection for children is rare [3]. About a quarter of patients with PG have arthritis the severity of which is unrelated to PG [4]. PG has been more commonly reported in context of seropositive RA and spondyloarthropathies and rarely in JIA [1, 5]. Extra-cutaneous lesion may involve lungs and bones (multifocal sterile recurrent osteomyelitis) and can precede cutaneous lesions [6, 7]. The timing and site of the biopsy determine the histopathology of PG [8]. The principle of biopsy is to exclude other conditions such as malignancy and infections. Treatment includes local care with moist dressings. Various topical and systemic therapies have been tried with varying success. Initial response to treatment can be seen within days to weeks but complete remission may require months to years [1]. In our patient, methotrexate was initiated primarily for the treatment of JIA and also because of reports of its efficacy in PG. The ulcer however responded dramatically to corticosteroid and topical tacrolimus. To the best of our knowledge, this is the first report of JIAassociated PG to be successfully treated in such a short span of time with a combination of topical tacrolimus and oral corticosteroid. Clin Rheumatol (2009) 28:489–490 DOI 10.1007/s10067-008-1066-y