A case of T-cell lymphoproliferative disorder associated with hypereosinophilia with excellent response to mycophenolate mofetil

Hypereosinophilic syndrome (HES) is a group of rare blood disorders characterized by a persistent elevation of blood eosinophil count ?1.5 × 10⁹/L and clinical manifestations attributable to eosinophilia or tissue hypereosinophilia. Lymphocytic variant of HES (HES-L) is a known subtype according to World Health Organization classification. It is well documented in the literature that patients with HES-L are predisposed to develop T-cell lymphoma. We report a case of T-cell lymphoproliferation associated with hypereosinophilia, which has been successfully treated with mycophenolate mofetil, with resolution of skin lesions and normalization of eosinophil count and immunoglobulin E level. We believe this is a clinically relevant case since this is a rare disease with little known knowledge on its best treatment modality.