LY24 Lymphomatoid papulosis in a patient on disease-modifying therapy for relapsing–remitting multiple sclerosis

Abstract

A 29-year-old woman with a history of relapsing–remitting multiple sclerosis on disease-modifying therapy presented with a 6-year history of a fluctuating skin rash first occurring during pregnancy. The rash was initially infrequent occurring once or twice a year but subsequently increased to six to eight times weekly. Prior to developing the rash she had been on natalizumab; this was stopped during pregnancy and she then commenced 6-monthly infusions of ocrelizumab (which targets B cells) after the birth. Although the rash predated commencement of ocrelizumab she noticed her skin often flared more severely following an infusion. Clinical examination showed multiple papules and nodules affecting her limbs, with crusting and central ulceration present. Lesions appeared necrotic at times. Itch was not a predominant factor; however, the lesions were described as uncomfortable and at times painful. She had multiple attendances to the emergency department and had several courses of antibiotics for presumed infective aetiology. Dermatology reviewed her in the emergency department and outpatient follow-up was arranged with biopsies for histology and culture. Histology showed superficial and deep dermal perivascular inflammation composed of lymphocytes, histiocytes and scattered eosinophils. Although suspicions at this time were focused on pityriasis lichenoides, discussion at the local clinicopathological conference meeting raised the possibility of lymphomatoid papulosis. A further tissue sample was arranged and sent to the specialist haematopathology lab in Leeds. This result was in keeping with a primary cutaneous CD30+ T-cell lymphoproliferative disorder. Our patient was subsequently started on oral methotrexate with multidisciplinary team input. Lymphomatoid papulosis is a rare cutaneous lymphoproliferative disease that often follows an indolent course. There have been previous case reports of this disease being associated with ­disease-modifying therapy in multiple sclerosis, which we believe is relevant in this case. This highlights the importance of clinicopathological correlation and increased vigilance in those on these immunosuppressive therapies.