No abstract available.
Epstein-Barr Virus Infections/*complications/diagnosis ; Herpesvirus 4, Human/pathogenicity ; Humans ; Lymphoma, Follicular/complications ; Lymphoproliferative Disorders/*complications/diagnosis/virology ; Male ; Middle Aged ; *T-Lymphocytes/pathology/virology

Chronic infection with Epstein-Barr virus (EBV) without previous immunodeficiency or immuno-suppressive therapy is relatively rare. Severe chronic active EBV (SCAEBV) infection was reported for the first time in 1984 as 'chronic mononucleosis syndrome', and diagnostic criteria were proposed. It is characterized by clinical features including fever, severe hepatosplenomegaly, lymphadenopathy, hematologic features such as anemia and thrombocytopenia, and elevated antibody titers to EBV. We experienced a 21-year-old woman who initially presented with fever and chronic fatigue; however, no definite diagnosis could be made at the time of admission. Three months after the initial admission, there was evidence of only splenomegaly and the patient had persistent, multiple, paraaortic lymphadenopathies in abdominal CT. Diagnostic splenectomy was performed, and SCAEBV infection with T-cell lymphoproliferative disorder was ultimately diagnosed.
Adult ; Chronic Disease ; Diagnosis, Differential ; Epstein-Barr Virus Infections/*complications/*diagnosis ; Female ; Humans ; Lymphoproliferative Disorders/*diagnosis/pathology/virology ; Severity of Illness Index ; Splenectomy ; *T-Lymphocytes ; Tomography, X-Ray Computed

Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, affecting >90% of the adult population. EBV targets B-lymphocytes and achieves latent infection in a circular episomal form. Different latency patterns are recognized based on latent gene expression pattern. Latent membrane protein-1 (LMP-1) mimics CD40 and, when self-aggregated, provides a proliferation signal via activating the nuclear factor-kappa B, Janus kinase/signal transducer and activator of transcription, phosphoinositide 3-kinase/Akt (PI3K/Akt) and mitogen-activated protein kinase pathways to promote cellular proliferation. LMP-1 also induces BCL-2 to escape from apoptosis and gives a signal for cell cycle progression by enhancing cyclin-dependent kinase 2 and phosphorylation of retinoblastoma (Rb) protein and by inhibiting p16 and p27. LMP-2A blocks the surface immunoglobulin-mediated lytic cycle reactivation. It also activates the Ras/PI3K/Akt pathway and induces Bcl-xL expression to promote B-cell survival. Recent studies have shown that ebv-microRNAs can provide extra signals for cellular proliferation, cell cycle progression and anti-apoptosis. EBV is well known for association with various types of B-lymphocyte, T-lymphocyte, epithelial cell and mesenchymal cell neoplasms. B-cell lymphoproliferative disorders encompass a broad spectrum of diseases, from benign to malignant. Here we review our current understanding of EBV-induced lymphomagenesis and focus on biology, diagnosis and management of EBV-associated B-cell lymphoproliferative disorders.
B-Lymphocytes/*pathology/*virology ; Diagnosis, Differential ; Disease Management ; Epstein-Barr Virus Infections/*complications ; Herpesvirus 4, Human/*physiology ; Humans ; Lymphoproliferative Disorders/*diagnosis/*etiology/therapy

Epstein-Barr virus, a ubiquitous human herpesvirus, can induce both lytic and latent infections that result in a variety of human diseases, including lymphoproliferative disorders. The oncogenic potential of Epstein-Barr virus is related to its ability to infect and transform B lymphocytes into continuously proliferating lymphoblastoid cells. However, Epstein-Barr virus has also been implicated in the development of T/natural killer cell lymphoproliferative diseases. Epstein-Barr virus encodes a series of products that mimic several growth, transcription and anti-apoptotic factors, thus usurping control of pathways that regulate diverse homeostatic cellular functions and the microenvironment. However, the exact mechanism by which Epstein-Barr virus promotes oncogenesis and inflammatory lesion development remains unclear. Epstein-Barr virus-associated T/natural killer cell lymphoproliferative diseases often have overlapping clinical symptoms as well as histologic and immunophenotypic features because both lymphoid cell types derive from a common precursor. Accurate classification of Epstein-Barr virus-associated T/natural killer cell lymphoproliferative diseases is a prerequisite for appropriate clinical management. Currently, the treatment of most T/natural killer cell lymphoproliferative diseases is less than satisfactory. Novel and targeted therapies are strongly required to satisfy clinical demands. This review describes our current knowledge of the genetics, oncogenesis, biology, diagnosis and treatment of Epstein-Barr virus-associated T/natural killer cell lymphoproliferative diseases.
Cell Transformation, Viral ; Epstein-Barr Virus Infections/*complications ; Herpesvirus 4, Human/*physiology ; Humans ; Killer Cells, Natural/immunology/metabolism/*pathology/*virology ; Lymphoproliferative Disorders/diagnosis/*etiology/therapy ; T-Lymphocytes/immunology/metabolism/*pathology/*virology

The World Health Organization (WHO) recently defined systemic Epstein-Barr virus (EBV)-positive T-cell lymphoproliferative disorders (LPD) of childhood as a life-threatening illness. However, this rare disease has not been extensively studied. Here we report a case of systemic EBV-positive T-cell LPD in a previously healthy middle-aged man with a chief complaint of chronic diarrhea. The initial colon biopsy showed focal infiltration of EBV-positive small lymphocytes without any atypia. However, the disease rapidly progressed and the patient required a total colectomy due to severe gastrointestinal bleeding. Three and half months after admission, the patient died from a complication of disseminated intravascular coagulation. The resected colon showed diffuse infiltration of EBV-positive atypical lymphocytes with ischemic change. Most atypical lymphocytes were CD3+ or CD5+. The monoclonality of EBV was demonstrated by sequence variation analysis of the latent membrane protein 1 (LMP1) gene in the colectomy specimen as well as in the initial biopsy.
Chronic Disease ; Colonoscopy ; Diarrhea/*diagnosis ; Disseminated Intravascular Coagulation/diagnosis ; Epstein-Barr Virus Infections/complications/virology ; Feces/virology ; Gastrointestinal Hemorrhage ; Herpesvirus 4, Human/genetics/*isolation & purification ; Humans ; Lymphoproliferative Disorders/*diagnosis/immunology/virology ; Male ; Middle Aged ; RNA, Viral/analysis ; T-Lymphocytes/*immunology/pathology