When Reactive Lymphadenopathy Isn’t Reactive: EBV-Associated Polymorphic Lymphoproliferative Disorder with Multidermatomal Herpes Zoster: A Case Report

Background: Epstein–Barr virus-associated lymphoproliferative disorders may present with persistent lymphadenopathy and can be difficult to distinguish from reactive lymphoid proliferation. Aim: This report describes a patient with progressive cervical lymphadenopathy in whom repeat tissue evaluation supported an Epstein–Barr virus-associated polymorphic lymphoproliferative disorder, followed by infectious and respiratory complications. Case Presentation: A 54-year-old woman presented with recurrent high-grade fever and subsequently developed cervical lymphadenopathy. An initial lymph-node biopsy was interpreted as reactive lymphadenopathy, and corticosteroid therapy was initiated. Because the lymph nodes continued to enlarge, a repeat excisional biopsy was performed. Histopathological examination demonstrated effacement of nodal architecture with immunoblasts and apoptotic cells in a polymorphous inflammatory background. Immunohistochemical evaluation showed latent membrane protein positivity, while quantitative Epstein–Barr virus polymerase chain reaction demonstrated a viral load of 750,500 copies/mL. During hospitalisation, the patient developed painful vesicular lesions involving multiple dermatomes of the right lower limb, consistent with multidermatomal herpes zoster. She subsequently developed hypotension, breathlessness and hypoxia. Chest computed tomography demonstrated bilateral pleural effusions with pneumonitic changes. She received antiviral and supportive treatment together with rituximab. Conclusion: Persistent or progressive lymphadenopathy despite an initially reactive biopsy warrants clinicopathological reassessment. Integration of tissue findings with virological investigations and careful surveillance for infectious complications are important in patients with Epstein–Barr virus-associated lymphoproliferative disorders.