Abstract A 27-year-old woman was diagnosed with systemic lupus erythematosus and successfully achieved remission. She remained in long-term remission without relapse while receiving prednisolone, tacrolimus, and hydroxychloroquine. At the age of 42, after receiving an influenza vaccination, she developed multiple, progressively enlarging, painless cervical lymph nodes and was referred to our hospital. She presented with fever and cervical lymphadenopathy. Laboratory examination revealed an elevated sIL-2 receptor of 3300 U/mL. Computed tomography demonstrated lymphadenopathy in the left posterior cervical and left submandibular regions, as well as paraaortic lymphadenopathy. 18F-fluorodeoxyglucose positron emission tomography showed abnormal uptake with a maximum standardized uptake value of 14.5. A biopsy of the left posterior cervical lymph node was performed. Histopathological examination showed findings compatible with malignant lymphoma; however, definitive classification was difficult because immunohistochemistry showed loss of CD20 expression in the atypical cells and plasmacytic differentiation. In situ hybridization for Epstein–Barr virus–encoded RNA was negative. Based on the biopsy findings, we diagnosed the patient with Epstein-Barr virus-negative polymorphic lymphoproliferative disorder. We discontinued tacrolimus at the initial visit, after which the lymphadenopathy gradually regressed with almost complete resolution six months later. Iatrogenic immunodeficiency–associated polymorphic lymphoproliferative disorder resulting in complete remission after tacrolimus withdrawal in a patient with systemic lupus erythematosus has not been previously reported. Clinicians should be aware that iatrogenic immunodeficiency–associated polymorphic lymphoproliferative disorder may occur during tacrolimus use and that discontinuation of the drug may lead to improvement of lymphadenopathy.
Yoshida et al. (2026) studied this question.