Biomedical subjects

Nancy Webb

Publications and source records attributed to Nancy Webb.

4 recordsLinked to original sources

PubMed2005

Lower CD4+ T lymphocyte nadirs may indicate limited immune reconstitution in HIV-1 infected individuals on potent antiretroviral therapy: analysis of immunophenotypic marker results of AACTG 5067.

BACKGROUND: Although initiation of potent antiretroviral therapy (ART) has significantly improved immune perturbations in individuals with AIDS, it is unclear which factors are most important in determining the degree of immune reconstitution. METHODS: Whole blood was analyzed at baseline and week 12 in six groups of subjects (n = 81): those with acute or following immune reconstitution after Pneumocystis jirovecii (previously known as Pneumocystis carinii) pneumonia (PcP) (two groups) and cytomegalovirus (CMV) retinitis (two groups), HIV-infection without AIDS (one group), and healthy volunteers (one group). Absolute CD4+ and CD8+ T lymphocytes, naive (CD45RA+) and memory (CD45RO+) CD4+ T lymphocytes and percentages of activated CD8+ T lymphocytes (CD8+/CD38+/HLA-DR), and CD28 expression on CD4+ and CD8+ T lymphocytes were enumerated. RESULTS: The reconstituted CMV group, which had a history of a lower CD4+ T lymphocyte nadir compared to the reconstituted PcP group (15 cells/mm(3) versus 48 cells/mm(3); p = .013), had significantly lower absolute CD4+, CD8+ and naive CD4+ T lymphocytes and a trend toward lower memory CD4+ T lymphocytes compared to the reconstituted PcP group. Moreover, no difference was noted between the reconstituted groups in the proportion of subjects with undetected HIV-1 RNA. The reconstituted subjects had significantly lower absolute CD4+, memory CD4+ and naive CD4+ T lymphocytes than the HIV-positive controls and a significantly higher percentage of activated CD8+ T lymphocytes with a lower percentage of CD8+CD28 expression than the HIV-negative controls. CONCLUSION: The association of CD4+ T lymphocyte nadir with the extent of immune reconstitution in HIV-infected individuals suggests that HIV-1 may cause irreparable immune system damage despite potent ART.

Adult↗

PubMed2005

GB virus C infection in children with perinatal human immunodeficiency virus infection.

BACKGROUND: GB virus C (GBV-C) infection occurs in 20-40% of human immunodeficiency virus (HIV)-infected adults, and coinfection is associated with improved HIV disease outcome. METHODS: To determine the prevalence of GBV-C infection in children who were perinatally infected with HIV, we conducted a cross-sectional prevalence survey in a cohort of perinatally infected HIV-positive children selected from a large, multicenter observational protocol. A blood specimen was obtained and tested for GBV-C viremia with the use of a qualitative GBV-C RNA assay and screened for past GBV-C infection with enzyme-linked immunosorbent assay to detect antibodies to the GBV-C envelope protein E2 (E2 Ab). RESULTS: The 354 children who participated in the substudy were relatively healthy, with a median CD4 of 784 cells/mm and median HIV-1 viral load of 1055 copies/mL. The prevalence of GBV-C viremia was 20 of 353 or 5.7% (95% confidence interval, 3.5-8.6%), and the prevalence of E2 Ab was 12 of 354 or 3.4% (95% confidence interval, 1.8-5.8%). GBV-C viremic patients were older than patients without past GBV-C infection (median age, 12.8 years versus 10.7 years). Median CD4 lymphocyte counts were highest in subjects without GBV-C infection and lowest in those with E2 Ab. CONCLUSIONS: GBV-C prevalence rates are lower in children with perinatal HIV infection than those reported for HIV-infected adults. With the exception of evidence that GBV-C viremic children had lower rates of Centers for Disease Control and Prevention HIV disease category C disease before GBV-C testing, we did not find evidence of improved HIV disease outcome in coinfected patients, but the number of HIV/GBV-C-coinfected children was small.

AIDS-Related Opportunistic Infections↗

PubMed2004

Hepatitis C prevalence in children with perinatal human immunodeficiency virus infection enrolled in a long-term follow-up protocol.

OBJECTIVE: To evaluate the prevalence of hepatitis C virus (HCV) infection in children with perinatal human immunodeficiency virus (HIV) infection. DESIGN: Cross-sectional substudy. SETTING: Multicenter study from 41 sites in the United States. PATIENTS: Children with perinatal HIV infection were randomly selected from a large, long-term, follow-up protocol. MAIN OUTCOME MEASURE: Hepatitis C infection was defined as having positive test results on both HCV antibody and HCV RNA assays. RESULTS: Five hundred thirty children enrolled in the substudy; definitive HCV test results were available for 525 children. Eighty-three percent were of a minority race or ethnicity. They were equally distributed by sex, had a median age of 10.7 years, and were relatively healthy, with 75% having CD4+ lymphocyte counts greater than 500 cells/mm3. Eight of 525 children (1.5%; 95% confidence interval [CI], 0.7%-3.0%) infected with HIV were coinfected with HCV. In contrast, the rate of HCV infection in a serosurvey of more than 2700 children aged 6 to 11 years from the National Health and Nutrition Examination Survey was 0.2% (95% CI, 0.04%-0.6%). In our study, there were no differences between children coinfected with HIV and HCV and those without HCV infection in terms of demographic characteristics, CD4+ or CD8+ T-lymphocyte counts, HIV 1 RNA levels, preterm or mode of delivery, or liver disease; however, the number of children coinfected with HIV and HCV was small. CONCLUSION: While HCV prevalence infection rates are low in children with perinatal HIV infection, they are 8 to 10 times higher than reported in HCV serosurveys of children in the United States.

Adolescent↗

PubMed2003

The Baycrest SARS experience: the human side.

Toronto, in the province of Ontario, Canada was one of the cities severely impacted by Severe Acute Respiratory Syndrome (SARS). SARS required the health care system to respond quickly and efficiently. This paper describes the situation and response at a large public academic aged care centre.

Academic Medical Centers↗