A Case of Spontaneously Improving Secondary HemophagocyticLymphohistiocytosis in an Adult Associated with T-CellHistiocyte-Rich Large B-Cell Lymphoma

Secondary hemophagocytic lymphohistiocytosis (HLH) in adults is a rare, often fatal syndrome characterized by widespreadimmune dysregulation. It is seen as a complication of infections, autoimmune diseases, and malignancies. Among the malignancy-related causes, aggressive T-cell or NK-cell neoplasms are most notable, while B-cell lymphomas are less commonly implicated.We present the case of a 32-year-old male transferred to our facility with concern for HLH. During the first week of hishospitalization, his diagnosis was confirmed and the patient demonstrated spontaneous improvement in his symptoms promptingus to delay therapy while searching for a primary cause. In the second week, the patient deteriorated, leading us to initiate steroidmonotherapy in the absence of a cause for his HLH. Meanwhile, pathology results from an excisional lymph node biopsyconfirmed a diagnosis of T-cell/histiocyte-rich large B-cell lymphoma (TCHRLBCL). Subsequently, we initiated therapy withdose-adjusted R-EPOCH. )e patient achieved a complete remission of both HLH and TCHRLBCL as well as a complete return tohis prior functional status. In our review of the literature, this represents only the second documented case of HLH associated withTCHRLBCL and the only documented case of an adult experiencing significant spontaneous recovery in this context.