Peripheral T-cell lymphomas (TCLs) are a heterogeneous group of aggressive, uncommon forms of T-cell or natural killer cell-derived non-Hodgkin's lymphomas. Acute tumor lysis syndrome (TLS) is a multiple metabolic derangement that occurs due to the treatment of malignancies or spontaneous tumor cell death. We report the case of a 56-year-old male patient who presented with marked eosinophilic leukocytosis, rash, and lymphadenopathy at the initial visit but finally manifested with TCL and spontaneous TLS. On the first visit, hemogram showed a marked eosinophilic leukocytosis and raised lactate dehydrogenase. The patient refused for admission; however, lymph node biopsy was done on day-care basis. After 3 days, the patient presented in the em...