Seroprevalence of Kaposi's sarcoma-associated herpesvirus infection among blood donors from Texas.

PURPOSE: Kaposi's sarcoma-associated herpesvirus (KSHV), a gammaherpesvirus recently discovered among AIDS patients with Kaposi's sarcoma, is a potential candidate for screening in blood and plasma donors. While a number of studies have assessed KSHV infection among U.S. blood donors, larger-scale population-based studies would be necessary to develop more refined estimates of the magnitude and variation of KSHV infection across different geographic regions of the U.S. blood supply. The goal of the present study, therefore, was to determine the seroprevalence of KSHV infection and to assess demographic correlates of KSHV infection among south Texas blood donors. METHODS: KSHV infection was determined using specific serologic assays that measure antibodies to KSHV latent and lytic antigens. RESULTS: The overall seroprevalence of KSHV in Texas blood donors (15.0%) is substantially higher than previously reported among blood donor and general population samples in the United States. This high rate of KSHV infection persisted across most of the sociodemographic subgroups under study but was particularly elevated among participants with less than a high school education. The infection rate also increased linearly with age. CONCLUSIONS: The elevated infection rate reported in the present study suggests that screening methods to detect KSHV infection in blood donors should be considered. In view of the etiologic role of KSHV for several malignancies, it would be important for future studies to directly assess the risk of KSHV transmission via blood transfusion.

Detection of EBV DNA in the cord blood donor for a patient developing Epstein-Barr virus-associated lymphoproliferative disorder following mismatched unrelated umbilical cord blood transplantation.

Epstein-Barr virus-associated post-transplant lymphoproliferative disorder (PTLD) has been well described as a complication following allogeneic stem cell transplantation but has only recently been reported following umbilical cord blood (UCB) transplant. We report the case of a child transplanted with unrelated mismatched UCB for juvenile chronic myelogenous leukemia (JCML) who developed EBV-associated PTLD, which was confirmed pathologically, 139 days following stem cell infusion. There was no clinical response to reduction of immune suppression, high-dose acyclovir, or alpha interferon. The patient died 160 days after transplantation. EBV was detected by polymerase chain reaction in the cord blood unit used for transplantation. This case demonstrates that EBV-associated PTLD can occur following mismatched unrelated UCB transplant and may be related to transmission of EBV infection by donor lymphocytes.

Absence of Epstein-Barr virus in smooth muscle cells of idiopathic hypertrophic pyloric stenosis.

CONTEXT: The etiology of idiopathic hypertrophic pyloric stenosis (IHPS) is unknown. Epstein-Barr virus (EBV) infects smooth muscle cells and is associated with leiomyomas and leiomyosarcomas of immunocompromised persons, including persons with the acquired immunodeficiency syndrome. OBJECTIVE: To determine whether EBV is causally associated with IHPS. DESIGN: Biopsy samples of the pylorus were obtained from 10 infants with projectile vomiting and pyloric hypertrophy on ultrasound, with confirmation of hypertrophy at the time of pyloromyotomy. The presence of EBV infection was tested by in situ hybridization for EBV-encoded RNA 1 (EBER1) in smooth muscle cells of IHPS. SETTING: Biopsy specimens were obtained from children treated for IHPS at a tertiary referral hospital and were tested in a clinical molecular diagnostics laboratory. RESULTS: All of the 10 smooth muscle biopsies were negative for EBER1. Cellular U6 RNA was detected in all smooth muscle samples, confirming that the RNA in the specimens was intact and capable of detection by in situ hybridization. CONCLUSIONS: The absence of EBER1 in 10 cases of clinically diagnosed and histopathologically confirmed cases of IHPS effectively excludes EBV infection of smooth muscle cells as a causal factor in the pathogenesis of IHPS.

Distinct distribution of rare US genotypes of Kaposi's sarcoma-associated herpesvirus (KSHV) in South Texas: implications for KSHV epidemiology.

Genotypes of Kaposi's sarcoma (KS)-associated herpesvirus (KSHV) from patients with KS in South Texas were examined. Open-reading frame (ORF)-K1 and ORF-K15 DNA segments from 16 KSHV isolates were amplified by polymerase chain reaction, and KSHV subtypes were assigned on the basis of sequence variations. K1 genotyping showed that 75% exhibited C subtype and 25% exhibited A subtype. K15 genotyping showed that 56% exhibited M form, of which 89% exhibited C3 K1 subtype and 44% exhibited P form. A unique isolate was found and was classified as C6 clade. All of the M KSHV isolates had been obtained from human immunodeficiency virus-negative classic KS patients >50 years of age, of whom 78% were Hispanic. Conversely, all KS patients with AIDS were <36 years of age and exhibited P form KSHV. These findings indicate that C3/M KSHV genotypes are more prevalent in South Texas (50%) than in other US regions (3%) and that M form KSHV likely existed in this region long before the AIDS epidemic.

Antiretroviral prescribing patterns in the Texas prison system.

Although the prevalence of human immunodeficiency virus (HIV) infection among prison inmates is reported to be high, little is known about anti-HIV treatment patterns in correctional institutions. The present study assessed antiretroviral prescribing patterns for 2360 Texas Department of Criminal Justice (TDCJ) inmates infected with HIV. In 1998, 66.8% of all TDCJ inmates infected with HIV who had CD4 lymphocyte counts < 500 cells/mm(3) were treated with highly active antiretroviral therapy (HAART). However, no substantial differences in the use of HAART were exhibited according to the sociodemographic factors under study. While the majority of inmates receiving HAART in 1998 were prescribed a combination of 2 nucleoside reverse transcriptase inhibitors (NRTIs) and 1 protease inhibitor, 11.2% were prescribed a combination of 2 NRTIs and 1 non-NRTI. In view of the elevated rate of HIV infection in correctional settings, it will be important to continue to document the pharmacotherapy patterns among prison inmates, both during and following incarceration.

Prospective 5-year study of peripheral blood CD4, CD8, and CD19/CD20 lymphocytes and serum Igs in children born to HIV-1 women. The P(2)C(2) HIV Study Group.

BACKGROUND: Peripheral blood CD4(+) and CD8(+) T cells, CD19(+)/20(+) B cells, and serum Igs are known to be altered by the progression of pediatric HIV-1 infection, but their evaluation as predictors of survival needs further definition. OBJECTIVE: To determine the natural history of these immune factors and their importance in predicting survival, we studied 298 HIV-1 vertically infected (HIV-1(+)) children over a 5-year period. METHODS: These immune factors and serum HIV-1 RNA levels were measured in two groups: (1) a birth cohort of children enrolled up to age 28 days postnatally, including 93 HIV-1(+) and 463 HIV-1 uninfected infants (HIV-1(-)), and (2) an older cohort of 205 HIV-1(+) children enrolled after the age of 28 days, who were classified as survivors or nonsurvivors. RESULTS: In the birth cohort HIV-1(+) children had significantly lower CD4(+) T-cell counts, higher CD8(+) T-cell counts, and lower CD19(+)/20(+) B-cell counts and higher IgG, IgA, and IgM levels than HIV-1(-) children. In the older cohort survivors had significantly higher CD4(+) and CD8(+) T-cell and CD19(+)/CD20(+) B-cell counts and higher IgG, lower IgA, and lower IgM levels than did nonsurvivors. In univariable analysis factors affecting survival in the older cohort were baseline CD4(+) and CD8(+) T-cell and CD19(+)/20(+) B-cell counts and IgG and HIV-1 RNA levels (all P <.05). In multivariable analysis high baseline CD4(+) T-cell count and low baseline HIV-1 RNA load remained important. CONCLUSION: The longitudinal mean profiles of CD4 and CD8 T-cell and CD19/20 B-cell counts and serum IgG levels helped to describe the natural progression of HIV-1 disease in children. However, only baseline CD4 T-cell count independently predicted survival.

Evaluation of human herpesvirus type 8 infection in childhood langerhans cell histiocytosis.

The etiology of Langerhans cell histiocytosis (LCH) is unknown. Viral causes, including human herpesvirus type 6 (HHV6), have been suggested but remain unproved. The recently discovered human herpesvirus type 8 (HHV8), the cause of Kaposi's sarcoma, infects dendritic cells in the bone marrow associated with multiple myeloma. Evidence for an association of HHV8 infection with LCH in children was studied by two approaches: indirectly by HHV8-specific serologic assays and directly by detection of HHV8 sequences using polymerase chain reaction in affected bone marrow samples. Using three different assays specific for HHV8 antibodies, 3 of 10 (30%) children with LCH had detectable HHV8 antibodies, which was not different from the prevalence of 5 of 30 (17%) in healthy controls of similar age (P = 0.65). Of bone marrow samples from three additional children with LCH, all had amplifiable DNA but were negative for HHV8 sequences. These studies of a small number of patients do not demonstrate an increased prevalence of HHV8 infection in children with LCH, and they do not suggest a causal role for HHV8 in the etiology of LCH.

Absence of herpesvirus DNA sequences in the 5T murine model of human multiple myeloma.

Kaposi's sarcoma-associated herpesvirus (KSHV, also known as HHV-8) has been found in patients with multiple myeloma (MM) and postulated to be aetiologically associated with the development of this common plasma cell malignancy. A murine model of MM was previously established in which intravenous transfer of 5T myeloma cells into C57BL/KaLwRij mice resulted in characteristic features of human MM. In the present study, we sought to identify herpesvirus DNA sequences in this murine model of MM through polymerase chain reaction (PCR) analysis using primers specific for KSHV, murine herpesvirus 68 (MHV68) and murine cytomegalovirus (MCMV) as well as consensus primers designed from the highly conserved DNA polymerase genes of the Herpesviridae family. None of the DNA samples from whole bone marrow (n = 6) or dendritic cells enriched by long-term culture (n = 8) of 5T myeloma-bearing mice as well as the 5T myeloma cell lines (n = 3) maintained in long-term culture yielded specific amplification products in any of the PCR assays. Two KSHV-specific serological assays measuring antibodies to KSHV latent and lytic antigens also failed to detect the presence of anti-KSHV antibodies in mice that developed MM. These results suggest that the development of 5T murine MM is unlikely to be involved with KSHV or a KSHV-like murine herpesvirus.

Acute complications of Epstein-Barr virus infectious mononucleosis.

Infectious mononucleosis caused by Epstein-Barr virus (EBV) usually resolves over a period of weeks or months without sequelae but may occasionally be complicated by a wide variety of neurologic, hematologic, hepatic, respiratory, and psychological complications. The strength of association of EBV with many of these complications remains based on scattered case reports, often using unsophisticated diagnostic tests, and the evidence for causation in many instances is unconvincing. There is little benefit of antiviral treatment of uncomplicated or complicated infectious mononucleosis. Corticosteroids may have a role in hastening resolution of some complications, especially upper airway obstruction and possibly immune-mediated anemia and thrombocytopenia, but should be used judiciously.

Epidemiology of herpesvirus papio infection in a large captive baboon colony: similarities to Epstein-Barr virus infection in humans.

The epidemiology of herpesvirus papio, a lymphocryptovirus similar to Epstein-Barr virus (EBV), was studied in a captive colony of >1900 baboons. Herpesvirus papio IgG antibody titers were measured by IFA. In total, 438 specimens from 296 baboons were assessed, including 116 serial specimens from 52 juveniles and 6 infants studied monthly for 1 year following birth and at age 18 months. Maternally derived antibody reached a nadir at 4 months of age. About 75% of animals at 12 months of age and >95% of animals after age 24 months demonstrated serologic evidence of herpesvirus papio infection. After age 3 years, the geometric mean titer was 1:60-75. The epidemiology of herpesvirus papio infection in baboons closely parallels that of EBV infection in humans. An animal model of lymphocryptovirus infection will facilitate investigations of human lymphocryptovirus biology.

Molecular and virologic characteristics of lymphoid malignancies in children with AIDS.

PURPOSE: To characterize AIDS-associated lymphoid malignancies in children. PATIENTS AND METHODS: We studied lymphomas and B-cell leukemias from 25 children with AIDS for immunoglobulin heavy chain gene clonality, c-myc oncogene abnormalities, and presence of HIV and Epstein-Barr virus. RESULTS: Monoclonal immunoglobulin gene rearrangements were identified in 22 of 23 cases tested, the single exception being one of mucosa-associated lymphoid tissue. Immunoglobulin gene/c-myc translocations were found in 3 of 4 cases of B (surface immunoglobulin-positive)-acute lymphoblastic leukemia, 8 of 11 small noncleaved cell lymphomas, and 1 of 5 large cell lymphomas. Mutations of c-myc were found in 2 of 13 small noncleaved cell lymphomas, 1 of 2 Epstein-Barr virus-positive mucosa-associated lymphoid tissue neoplasms, and 1 of 4 Epstein-Barr virus-negative B-acute lymphoblastic leukemia. Six small noncleaved cell lymphomas, both mucosa-associated lymphoid tissue neoplasms and one of large cell lymphoma had high levels of Epstein-Barr virus in tumor tissue. Hodgkin's disease tissue and B-acute lymphoblastic leukemia tumors were negative for EBV. Proviral HIV-1 was not detected in any tumor. CONCLUSIONS: AIDS-associated lymphoid malignancies in children appear to have a different distribution of histologic subtypes than adult HIV-infected individuals, fewer large cell lymphomas occur in children. The small noncleaved cell lymphomas exhibit a lower frequency as well as different locations of c-myc mutations than AIDS-associated small noncleaved cell lymphomas in adults.

Prevalence of Cryptosporidium parvum infection in children along the Texas-Mexico border and associated risk factors.

We examined the epidemiology of Cryptosporidium parvum in children aged 6 months to 13 years living in 1) colonias along the border (n = 105), 2) a clinic in an urban border community (n = 65), and 3) clinics in a large urban nonborder area (n = 109). Serum IgG and IgA anticryptosporidial antibodies were measured by enzyme-linked immunosorbent assay (ELISA). Overall, 70.2% (196/279) of subjects had detectable C. parvum antibodies. Prevalence rates were higher (93/105 [89%]) in the colonias and urban border community (53/65 [82%]) compared to the urban nonborder community (50/109 [46%]). Within colonias, independent risk factors for C. parvum infection included consumption of municipal water instead of bottled water, older age, and lower household income. Children living along the Texas-Mexico border have a higher rate of infection with C. parvum compared to children living in a large nonborder urban area. Within colonias, C. parvum infection was associated with source of water supply, age, and socioeconomic status.

Evaluation of immune survival factors in pediatric HIV-1 infection.

Peripheral blood CD4+ and CD8+ T cells, CD19+/20+ B cells, and serum immunoglobulins (Igs) have been implicated as survival factors for pediatric HIV-1 infection. To determine which of these immune factors might be important in predicting survival, we studied HIV-1 vertically infected (HIV-1+) children over a 5-year period. Peripheral blood lymphocytes and Igs were measured in 298 HIV-1+ children, who were classified as survivors or nonsurvivors, and in 463 HIV-1 vertically exposed and noninfected (HIV-1-) children. Measurements of other possible survival factors were included in this study: albumin, hemoglobin, lactic dehydrogenase (LDH), and HIV-1 RNA levels. Survivors had significantly higher CD4+ T-cell, CD8+ T-cell, and CD19+/CD20+ B-cell counts and serum IgG levels, but lower serum IgA and IgM levels than nonsurvivors. Serum albumin and blood hemoglobin levels were higher, but serum LDH and HIV-1 RNA levels were lower in the survivors compared to nonsurvivors. In univariable analysis, factors affecting survival were baseline CD4+ T-cell and CD8+ T-cell counts, IgG, albumin, hemoglobin, LDH, and HIV-1 RNA (all p < 0.001). In multivariable analysis, high baseline CD4+ T-cell count, IgG and albumin levels, and low baseline HIV-1 RNA load remained important factors for survival. Serum IgG level has been identified as an immune factor that independently predicts survival, in addition to the already established CD4+ T-cell count. The HIV-1 RNA and serum albumin levels also predicted survival.

Smokeless tobacco extracts modulate exogenous gene expression in early passage cultured human oral epithelial cells: an in vitro system to study chemical and viral enhancer/promoter interaction.

The increased risk for cancers of the oral cavity from smokeless tobacco use may reflect the interaction of tobacco with genetic factors, such as oncogenes, and other exogenous factors, such as viruses. An in vitro system was developed based on expression of the chloramphenicol acetyltransferase (CAT) reporter gene to study interactions of chemical treatments with viral enhancer/promoters in early passage cell cultures of oral cavity-derived epithelial cells. Expression of CAT in transfected cells was significantly greater with CAT under the control of the cytomegalovirus immediate early enhancer/promoter (pCEP4/CAT) compared to the Rous sarcoma virus long terminal repeat enhancer/promoter (pRSV-cat) and the simian virus 40 (SV40) early promoter (pSV2-cat). No CAT expression was detected using corresponding control plasmids without the CAT reporter gene. Using this system, smokeless tobacco extracts prepared from either dry snuff or moist snuff delayed maximum CAT expression from Day 4 to Day 5, with sustained, significantly increased CAT expression at 12 days compared to the declining CAT expression observed in untreated control cells. Smokeless tobacco extracts can modulate intracellular gene expression. This system provides an in vitro model to test specificity of toxic agents on enhancer/promoter activity and the interaction on exogenous gene expression.

Molecular polymorphism of Kaposi's sarcoma-associated herpesvirus (Human herpesvirus 8) latent nuclear antigen: evidence for a large repertoire of viral genotypes and dual infection with different viral genotypes.

Molecular polymorphism was found in Kaposi's sarcoma-associated herpesvirus (KSHV) latent nuclear antigen (LNA), mapped to the internal repeat domain of the encoding orf73 gene, and used to develop a novel genotyping technique, KSHV LNA genotyping (KVNAtyping). KVNAtype was stable during latent and lytic viral replication in cell culture and in humans. Diverse KVNAtypes were identified in 43 specimens: 6 KSHV cell lines and 6 Kaposi's sarcoma (KS) and 4 primary effusion lymphoma (PEL) tumor samples from the United States, 15 KS tumor samples from Italy, and 12 KS tumor samples from Zambia. A single KVNAtype was detected in each of 41 specimens, and 2 KVNAtypes were detected in each of 2 KS specimens. Multifocal KS from 3 patients showed the same single KVNAtype at all sites in each patient. These results demonstrate a large repertoire of KSHV genotypes and suggest that the development of most KSs and PELs is associated with a single viral genotype.

Kawasaki syndrome-like illness associated with infection caused by enterotoxin B-secreting Staphylococcus aureus.

Two children had symptoms and clinical signs that were characteristic of the diagnostic criteria for Kawasaki syndrome, temporally associated with Staphylococcus aureus bacteremia. One child initially had focal osteomyelitis that was evident clinically and radiographically, and radiographic evidence of multifocal osteomyelitis was noted at follow-up. The blood-borne S. aureus isolates from these two patients secreted staphylococcal enterotoxin B and were negative for toxic shock syndrome toxin. Staphylococcal and streptococcal superantigens may play a role in the pathogenesis of some cases of Kawasaki syndrome or Kawasaki syndrome-like illness.

Effects of smokeless tobacco and tumor promoters on cell population growth and apoptosis of B lymphocytes infected with epstein-barr virus types 1 and 2.

The effects of smokeless tobacco purified products 4-(N-methyl-N-nitrosamine)-1-3-pyridinyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN), smokeless tobacco extracts (dry snuff, moist snuff, and loose leaf), and the tumor promoters 12-O-tetradecanoyl phorbol-13-acetate (TPA) and n-butyrate on cell population growth, cell death, and apoptosis were studied in B lymphocyte cell lines harboring Epstein-Barr virus (EBV) type 1 (Raji and X50-7) or type 2 (HR-1K and AG876) and in an EBV-uninfected control lymphocyte cell line (Ramos). Spontaneous apoptosis was present in all EBV-infected cell lines, but at varying levels. Spontaneous and induced apoptosis were generally greater by Student-Newman-Keuls tests in cells harboring EBV type 2 compared to EBV type 1. The greatest effects on cell population growth, cell death, and apoptosis on cells harboring lytic EBV type 1 (X50-7) was with each of the three smokeless tobacco extracts. The greatest effects on cells harboring EBV type 2 was with TPA and n-butyrate. There were no effects of smokeless tobacco extracts on the Raji cell line that harbors EBV type 1 incapable of lytic replication. Smokeless tobacco purified products, NNN and NNK, had no discernible effects. At the concentrations used in these experiments, there appears to be an EBV type-specific response to chemical induction, with greater susceptibility of lytic EBV type 1 to smokeless tobacco extracts and lytic EBV type 2 to TPA and n-butyrate. This EBV type-specific susceptibility to the effects of smokeless tobacco extracts is another phenotypic difference between EBV types. The use of smokeless tobacco products may affect B lymphocytes infected with replication-capable EBV in the oropharynx. The absence of significant effects with NNK and NNN suggests that these properties reside with other compounds present in tobacco extracts.