Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human immunodeficiency virus-1 (HIV-1) infection is a fatal retroviral infection that may first present clinically as enlargement of the lymphoid tissues of Waldeyer's ring. These tissues are a major site of viral replication. The presence of the virus in these tissues causes a unique constellation of diagnostic histopathologic features, including florid follicular hyperplasia, follicle lysis, and productively HIV-1-infected multinucleated giant cells of probable dendritic cell origin. Serologic evaluation is confirmatory of HIV infection. With the recent advances in antiretroviral chemotherapy, the early institution of which may significantly prolong life and disease-free interval, the recognition of the clinical and pathologic parameters of HIV-related enlargement of Waldeyer's ring tissues is essential.
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PMID:Human immunodeficiency virus-1 infection of the lymphoid tissues of Waldeyer's ring. 922 66

Lymphoid hyperplasia of Waldeyer's ring (WR) is an often-symptomatic complication of human immunodeficiency virus (HIV) infection. A characteristic but not well explained finding is the presence of multinucleated giant cells (MNGCs) adjacent to crypt or surface epithelium. To further elucidate the MNGCs and assess their relationship to HIV and Epstein-Barr virus (EBV), 12 specimens from 11 HIV-positive patients were stained with antibodies to HIV-1 p24, EBV (latent membrane protein, LMP-1), histiocytes (CD68), and other antigen-presenting cells: S-100 protein, the Langerhans cell (LC) marker CD1a, and the follicular dendritic cell (FDC) marker (CD21). Double immunofluorescent staining to assess co-expression of p24 and cell-specific markers was performed and analyzed by laser-scanning confocal microscopy with 3-dimensional reconstruction. In situ hybridization for EBV-encoded small RNA (EBER) was performed in all cases. Immunostains showed MNGCs labeled for p24, S-100, and CD68, but not CD1a. In 1 case, rare MNGCs were CD21-positive. EBV LMP-1 was uniformly negative, although EBER-positive lymphocytes were seen by in situ hybridization in 9 of 12 specimens (numerous in only 3 specimens). Double immunofluorescent staining showed co-localization of p24 with CD68 and S-100. Our results suggest that MNGCs are generally HIV-infected, EBV-negative, and most likely represent an unusual S-100-positive histiocyte subset (not LC or FDC). Their exact pathophysiologic role remains uncertain. EBV does not appear to play a major role in the pathogenesis of WR lymphoid hyperplasias in HIV infection.
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PMID:HIV-associated Waldeyer's ring lymphoid hyperplasias: characterization of multinucleated giant cells and the role of Epstein-Barr virus. 1057 22

Post-transplantation lymphoproliferative disorder is a well-documented complication of solid organ or bone marrow transplantation. Histologically, it is characterized by an abnormal proliferation of lymphocytes, which can range from benign B-cell hyperplasia to malignant lymphoma. Non-Hodgkin's lymphoma (NHL) is associated with several risk factors, such as congenital or acquired immunodeficiency states, autoimmune disorders, and infectious agents (eg, Epstein-Barr virus). Primary sites of presentation in the head and neck are Waldeyer's ring, paranasal sinuses, salivary glands, the oral cavity, and the larynx. Clinical appearance of gingival NHL varies but is usually found to be an asymptomatic gingival enlargement or mass resembling a pyogenic granuloma. We present a patient with a gingival ulceration that was subsequently diagnosed as Epstein-Barr virus malignant lymphoma resulting from the immunosuppression needed to prevent graft-versus-host disease after bone marrow transplantation.
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PMID:Unusual gingival presentation of post-transplantation lymphoproliferative disorder: a case report and review of the literature. 1102 79

Hyperplastic lymphoid tissues of the Waldeyer's ring in human immunodeficiency virus (HIV)-infected patients may occasionally contain multinucleated giant cells (MGCs). These cells, which are unrelated to any opportunistic infection, previously have been demonstrated to harbor significant amounts of HIV. Studies undertaken to characterize these MGCs have generated conflicting results: some reports suggested a macrophage origin, whereas others supported a dendritic cell lineage. This study was performed to determine the occurrence of MGCs in a series of adenoid/tonsil specimens from HIV-seropositive patients showing no histological evidence of opportunistic infection in order to further characterize the phenotype of these cells and to investigate the role of a viral infection in their pathogenesis. Adenoid/tonsil tissue specimens from 21 HIV-seropositive patients with no documented opportunistic infection were scrutinized for the presence of MGCs and evaluated immunohistochemically on paraffin sections by antibodies directed against various macrophage and DC antigens. These antigens included CD68, the macrophage marker 3A5, major histocompatibility complex Class II, S-100 protein, CD1a, and CD83. Additional immunostainings directed at CD21 and CD35 as well as at the HIV-associated p24 antigen were also performed. Finally, the presence of Epstein-Barr virus and human herpesvirus 8 viral sequences was investigated by in situ hybridization and by polymerase chain reaction analysis, respectively. MGCs were found in 14 patients (66.7%), regardless of gender, age, method of viral transmission, CD4 cell count, viral load, or ethnic group. These cells were mostly localized at the lymphoepithelium layer of the tonsillar crypts and, to a lesser extent, in the interfollicular areas of the underlying lymphoid tissue, which consistently exhibited features of follicular hyperplasia. Phenotypically, MGCs were found to be CD68+, 3A5+, major histocompatibility complex Class II+, S-100 protein+/-, CD1a-, CD21-, CD35-, and CD83-. Although the HIV-associated p24 protein was consistently present in the cytoplasm of these cells, no sign of Epstein-Barr virus or human herpesvirus 8 infection could be demonstrated. Consequently, our study didn't show any conclusive evidence to support that MGCs in hyperplastic lymphoid tissues of the Waldeyer's ring from HIV-seropositive patients originated from dendritic cells. The definite nature of these cells has yet to be elucidated, but it is plausible that they simply represent activated macrophages that are infected with HIV present in the oropharyngeal secretions during the circulation of their precursor through the lymphoepithelium area of adenoids and tonsils.
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PMID:HIV-associated multinucleated giant cells in lymphoid tissue of the Waldeyer's ring: a detailed study. 1114 25

Burkitt's lymphoma (BL) is one of the fastest growing malignancies in the pediatric population in the United States. BL is a high-grade B-cell Non-Hodgkin's lymphoma (NHL) which exists in endemic, sporadic, and human immunodeficiency-associated subtypes. The African, or endemic, variant usually involves the maxilla and other facial bones while head and neck manifestations in non-endemic BL are rare. We present three unusual present ations of sporadic BL stemming from Waldeyer's ring and the orbit. The clinical and pathologic features of BL are reviewed.
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PMID:Sporadic Burkitt's lymphoma of the head and neck in the pediatric population. 1256 Jan 51