HIV-related malignant lymphomas. A clinical and pathological study of 13 cases

Malignant lymphomas in Japanese AIDS patients

Seven non-Hodgkin's malignant lymphomas (MLs) were found in 25 Japanese AIDS (acquired immune deficiency syndrome) patients who died at two hospitals in Tokyo. All of these MLs originated from extranodal organs including the brain (three cases), skin (two cases) liver and adrenal gland. B cell markers were demonstrated in all of them. Epstein-Barr virus (EBV) capsid antigen (EBVCA) was demonstrated in 5/7, nuclear antigen (EBNA) in 2/2, the W fragment of EBV DNA by in situ hybridization in 5/7 and the same fragment by PCR in 6/7, indicating high association of these MLs with EBV. The adult T cell leukemia/lymphoma (ATL), endemic in south-west Japan and known to have a high association with HTLV-I, was not found in this series. The incidence of ML among the present AIDS cases is higher than in any other autopsy reports from western countries, although statistical analysis did not show this to be significant in comparison to some of these reports at a level of p less than 0.05. In spite of apparent higher incidence, the histopathologic and immunophenotypic characteristics of AIDS-associated MLs in Japan are in accordance with those in western countries.

Intracerebral Hodgkin's disease in a human immunodeficiency virus-seropositive patient

Intracerebral involvement of Hodgkin's disease (HD) is rarely described, with only 42 cases in the literature. Since the outbreak of the acquired immune deficiency syndrome (AIDS) epidemic, there has been an increasing number of human immunodeficiency virus (HIV)-infected (HIV+) persons who have diffuse non-Hodgkin's lymphoma and, more recently, atypical aggressive HD. The authors report the case of a patient with a history of intravenous drug abuse (IVDA) and Stage IVB HD who, after a drug-induced clinical remission, had intracerebral mixed-cellularity HD. This appears to be the first report of intracerebral HD in a person who is HIV+.

Hodgkin's disease in association with human immunodeficiency virus infection. Pathologic and immunologic features

Six patients with Hodgkin's disease (HD) and demonstrable serum antibodies to human immunodeficiency virus (HIV) and two additional patients with HD belonging to HIV-associated high-risk groups but with negative HIV serology were studied. All patients were men and ranged in age from 21 to 45 years. The HIV risk factors included homosexuality (6), intravenous drug abuse (2), and hemophilia A (1). All patients had high pathologically determined stage (one Stage III and seven Stage IV), and bone marrow involvement was observed in five patients with the initial diagnosis of HD based on marrow biopsy in two cases. Four cases were histologically subclassified as mixed cellularity (MC) and three as nodular sclerosis (NS); one patient underwent only bone marrow biopsy and was not subclassified. Histologically all cases were characterized by numerous Reed-Sternberg cells and variants, and with the exception of one case, all had a distinctive decrease in the proportion of reactive background lymphocytes compared with what is usually expected in MC or NS Hodgkin's disease (relative lymphocyte depletion). Flow-cytometric immunophenotypic studies done on cell suspensions from diagnostic lymph node biopsies in four cases showed decreased CD4:CD8 ratios (mean = 1.4) compared with expected values of 4 to 6. The relative lymphocyte depletion observed histologically is probably a reflection of the decreased tissue CD4:CD8 ratios, and this impairment of host immune response may be related to the observed high stage in all eight cases. Patients with high stage HD and the described histologic and immunologic features should be evaluated for the presence of HIV infection.

Immunological dysregulation of lymph nodes in AIDS patients

Changes in immune competent tissues of the HIV-1-infected person reflect to a certain extent the kind and intensity of immunological dysregulations. The diagnostic approach, however, must include immunophenotyping of cells, immunovirological studies of virus distribution in diseased tissues, and functional tests in addition to classical morphology. The latter technique alone just serves as a crude screening method since structural lesions in lymphoid tissues do not permit discrimination from other HIV-independent immune deficiency and autoimmune disorders. Although the overall appearance of lymph nodes in HIV infection and in chronic autoimmune disorders, such as collagen vascular diseases (e.g., rheumatoid arthritis and systemic lupus erythematosus), is similar, immunophenotyping shows a progressive loss of CD4 cells in HIV infection yet a quantitative increase in this cell population in autoimmune disorders (Krueger 1985a). In addition, there are other persistent active infections by lymphotropic viruses (e.g., EBV or HHV-6) which can cause structural and cellular changes in lymphoid tissues closely resembling HIV-induced lesions (Krueger et al. 1988b; Krueger 1985b). The pathological diagnosis therefore nedds to be supplemented by serological studies and--in selected cases--by in situ hybridization for the demonstration of viral genome. Southern blotting for viral DNA can only detect high numbers of viral genome copies in tissue extracts, not in which cell population the virus resides (e.g., malignant cells vs associated "normal" cells), while the polymerase chain amplification reaction, the most sensitive of all (Buchbinder et al. 1988), cannot yet differentiate between latent and (disease-related) active infection. Taking into consideration the above-described precautions in the evaluation of lymphatic lesions, there are a number of characteristic changes which reflect well the sequelae of HIV infection itself and of the ensuing immune dysregulation. Progressive loss of CD4 cells in the paracortex of lymph nodes and in the peripheral blood leads to inversion of the CD4/CD8 ratio. Loss of demonstrable CD4 cells is probably the consequence not only of cell lysis by HIV-1 infection (note: discrepancy between HIV-1 genome positive cell numbers and depletion of CD4 cells) but also of decreased CD4 marker synthesis in infected cells (Stevenson et al. 1987). In this context it is interesting that Fouchard et al. (1986) were able to show HIV expression in CD8 cells and theorized that these developed from infected CD4 cells which subsequently lost the CD4 epitope and expressed CD8.(ABSTRACT TRUNCATED AT 400 WORDS)