Opportunistic infections mimicking post-transplant lymphoproliferative disorder in transplant recipients: a scoping review of reported cases

Post-transplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ and hematopoietic stem cell transplantation. Opportunistic infections may closely resemble PTLD clinically, radiologically, or histopathologically, creating a diagnostic uncertainty potentially leading to inappropriate clinical management. This scoping review synthesizes published cases of opportunistic infections initially suspected to represent PTLD to characterize their presentation, diagnostic pitfalls, and clinical outcomes. Following PRISMA-ScR guidelines, we searched PubMed, PubMed Central, and EMBASE through September 30, 2025, for reports of opportunistic infections initially suspected as PTLD in transplant recipients. Data on patient demographics, transplant characteristics, pathogens, clinical presentation, diagnostic evaluation, management, and outcomes were extracted and summarized descriptively. Thirty-five studies reporting 37 individual cases met the inclusion criteria. Most patients were solid organ transplant recipients (97%), with kidney transplantation predominating. The median age of patients was 44.5 years, and the median interval from transplantation to clinical presentation was 48 months. Bacterial infections were the most common (51%), led by Bartonella henselae , followed by fungal (27%), parasitic (14%), and viral (8%) infections. Radiological mimicry was the predominant mechanism leading to suspicion of PTLD, whereas histopathological examination ultimately established the correct diagnosis in most cases. Tissue biopsy, combined with pathogen-specific microbiological or molecular testing, was central for the diagnosis. Diagnostic delays resulted in inappropriate PTLD-directed therapy in several patients and were associated with severe complications, including graft dysfunction and death. Opportunistic infections represent important mimics of PTLD across a broad range of pathogens and organ systems. Because imaging findings and EBV-associated laboratory abnormalities lack specificity, early tissue diagnosis integrated with microbiological and molecular investigations is essential before initiating PTLD-directed therapy. Greater awareness of these infectious mimics may reduce diagnostic error, preserve graft function and improve outcomes in transplant recipients. Not applicable.