Prevalence of HTLV-I-associated T-cell lymphoma

In order to assess the prevalence rate of HTLV-1-associated T-cell lymphomas and human retrovirus infection in general, approximately 21,000 individuals representing various patient populations, retroviral risk groups, and blood donors were examined for HTLV-I, HTLV-II, HIV-1, or HIV-2 infection using serologic and PCR assays. The prevalence rates among volunteer blood donors were 0.02% and 0% for HTLV and HIV, respectively. Significantly increased HTLV prevalence rates were observed among paid blood donors, African American health care clinic patients, Amerindians, recipients of HTLV-positive cellular blood products, intravenous drug users, sexual contacts and family members of HTLV-positive people, and patients with primary thrombocytosis and other-than-low-grade non-Hodgkin's lymphoma (NHL). Among some of these groups there were significant differences in the prevalence of HTLV-I versus HTLV-II. The eight HTLV-positive NHL patients all had mature, high-grade, CD4+ T-cell lymphomas with clonally integrated HTLV-I, for a prevalence of 4% among other-than-low-grade NHL patients. Seven of the eight died from their disease within 2 years despite treatment. Interestingly, two groups at risk for HTLV infection, namely needle stick victims and recipients of HTLV-infected and/or pooled plasma products, showed no evidence for infection. Significantly increased HIV-1 prevalence was observed among paid blood donors, African Americans, homosexuals, female prostitutes, hemophiliacs, and other-than-low-grade NHL patients. Only one patient was infected with HIV-2. Of the nine HIV-positive, other-than-low-grade NHL patients, seven HIV-1 positives had B-cell lymphomas, one HIV-1 positive had an HTLV-I-positive CD4+ T-cell lymphoma, and one infected with HIV-2 had a CD4+ T-cell lymphoma that was HTLV negative. The data indicate that HTLV-I lymphoma, while uncommon, is not necessarily rare among other-than-low-grade NHL cases in the United States and, given its poor prognosis, should probably be studied separately in clinical trials.

Non-cytocidal natural variants of human immunodeficiency virus isolated from AIDS patients with neurological disorders

To understand the mechanism of HIV-mediated neuropathology five viral isolates were obtained from four AIDS cases with central nervous system manifestations as the primary involvement. The isolates were identified as HIVs by antigenic cross-reactivity and nucleic acid hybridizations to HIV-specific antibodies and DNA probes. The replication and cytopathic properties of these isolates were studied and compared with lymphadenopathy-associated virus (HIVLAV). All isolates had replication competence equivalent to LAV, but four isolates did not kill T4 (CD-4) cells. This isolation of non-cytocidal natural variants of HIV raises the possibility that in some AIDS cases the neurological disorders might be due to HIV variants that are non-cytocidal to T4 cells. The results also indicate that virus replication and cytotoxicity are not always concordant functions in HIV.

Atypical presentation of childhood acquired immune deficiency syndrome mimicking Crohn's disease: nutritional considerations and management

A child with acquired immune deficiency syndrome became severely malnourished presumably as a result of multiple gastrointestinal infections, with numerous organisms including campylobacter, giardia, and cryptosporidium. These opportunistic infections preceded laboratory evidence of immune deficiency. Despite severe diarrhea and marked weight loss, there was no laboratory evidence of significant malabsorption. By using nasogastric feedings, we were successful in promoting a 60% weight gain, and a rise in serum albumin from 1.2 to 4.3 g/dl. While eventual outcome was not altered, this particular patient's clinical course was improved. We suggest that malnutrition should not be accepted as inevitable and that malabsorption should not be assumed in similar acquired immune deficiency syndrome patients. Appropriate studies for malabsorption should be done, and high caloric enteral feedings should be used whenever feasible.

An immunodeficient child with inflammatory bowel disease: involvement of cyclic nucleotides and effects of lithium

A 3-year-old male with inflammatory bowel disease and hypogammaglobulinemia was found to have decreased T lymphocyte function. His serum was shown to depress normal T cell proliferative responses to phytohemagglutinin. Incorporation of lithium chloride to in vitro cultures enhanced autologous lymphocyte responses to phytohemagglutinin. Since lithium acts by inhibiting cAMP production, the child's lymphocytes were postulated to have increased levels of cAMP. Both lymphocytes and serum were shown to contain elevated levels of cAMP. In vivo therapy with lithium citrate was initiated and enhanced T cell numbers and function were observed concomitantly. Serum cAMP was also reduced to normal levels. The patient showed initially marked clinical improvement as assessed by mood, weight gain, and diminution of diarrhea. This clinical improvement was unfortunately not sustained despite the continued improvement in immune parameters and cAMP levels.

Analyses of lymphocytes from patients with rheumatoid arthritis and systemic lupus erythematosus. Occurrence of interfering cold-reactive antilymphocyte antibodies

Large percentages of the lymphocytes from some patients with rheumatoid arthritis and systemic lupus erythematosus were densely covered with Ig demonstrable by immunofluorescence, which was occasionally present in the form of caps. The amount and character of the Ig staining depended largely on the procedures used in the isolation and washing of the lymphocytes. Cold-reactive antilymphocyte antibodies present in many sera wre primarily responsible for these variations. Overnight culture of the lymphocytes proved to be an efficient procedure for the removal of adsorbed antibody. Some evidence was also obtained for the presence of circulating immune complexes and exogenous rheumatoid factor molecules on the lymphocyte surface. Thus on freshly isolated cells the demonstration of surface Ig proved to an unreliable marker of bone marrow-derived (B) cells in these disease: the actual percent of B cells with intrinsic surface Ig was often markedly decreased. In patients with systemic lupus erythematosus, this reduction was in agreement with the low numbers of cells that had a receptor for aggregated IgG. The mean percentage of thymus-derived (T) cells in both diseases was slightly greater than the normal level.The concentrations of lymphocytes in joint fluids from patients with rheumatoid arthritis were often greater than levels found in blood. T cells primarily accounted for this increase. The T cells typically formed unusually dense rosettes with sheep erythrocytes. B lymphocytes were proportionally much diminished. Evidence was obtained for the existence of a major joint fluid lymphocyte population that lacked all assayed surface markers.