Epstein–Barr virus infected natural killer cell lymphoma in a patient with hypersensitivity to mosquito bite

Hypersensitivity to mosquito bite (HMB) can occur in association with chronic Epstein–Barr virus (EBV) infection and natural killer (NK) cell leukaemia/lymphoma, which was named ‘Tokura-Ishihara disease’. This disease is very rare and most previous reports have been documented in Japan. We present a patient who suffered from of pustules on skin, high fever, myalgia and multiple lymph node enlargements after mosquito bite from childhood. Recently, multiple lymph nodes were palpable on his both inguinal area. Peripheral blood smear (PBS) revealed many large granular lymphocytes and the skin lesion showed a dense dermal and subcutaneous infiltrate of lymphocytes. The lymph nodes and perinodal adipose tissue were infiltrated by atypical lymphoid cells in which EBER-positive signals were identified by in situ hybridization using EBV encoded RNA-1 probe. He was diagnosed as having Tokura-Ishihara disease and receives chemotherapy now. Here, we report a case of this disease with a precise pathological description on the lymph node biopsy.