Effect of age on the CD4⁺ T-cell impairment in HIV-infected persons without and with cART.

BACKGROUND: Knowledge about HIV infection in older persons is becoming increasingly important. CD4⁺ T cells are essential for protective immunity, but little is known about the effect of age on the CD4⁺ T-cell impairment in HIV infection. METHODS: Treatment-naive patients aged older than 50 or younger than 40 years were studied for absolute and relative frequencies of CD31⁺ naive and CD31⁻ naive CD4⁺ T cells, central memory, effector memory, and terminally differentiated CD4⁺ T cells, and compared with age-matched controls. In addition, cellular proliferation and cytokine secretion properties were determined. CD4⁺ T-cell reconstitution was analyzed in older and younger patients with <350 or ≥ 350 CD4⁺ T cells per microliter at initiation of combination antiretroviral therapy (cART). RESULTS: CD4⁺ T cells of older but not younger HIV-infected patients showed age-inappropriate low levels of CD31⁻ naive cells, increased levels of effector memory cells, and enhanced interferonγ and interleukin-17 secretion. Impaired CD4⁺ T-cell composition persisted in patients who initiated cART at <350 CD4⁺ T cells per microliter. In patients with CD4⁺ T cells ≥ 350 per microliter, alterations were less pronounced and were reversible with cART. Compared with age-matched controls, total CD4⁺ T-cell counts did not differ between treated younger and older HIV-infected patients. CONCLUSIONS: These data demonstrate that aging enhances the CD4⁺ T-cell impairment in HIV-infected persons mainly by a loss of CD31⁻ naive cells, accumulation of effector memory cells, and increased pro-inflammatory effector functions. Age-related changes in CD4⁺ T-cell composition can be prevented by an early initiation of cART.

Risk factors for treatment denial and loss to follow-up in an antiretroviral treatment cohort in Kenya.

OBJECTIVES: To evaluate risk factors for treatment denial and loss to follow-up in an antiretroviral treatment (ART) cohort in a rural African setting in western Kenya. METHOD: Sociodemographic and clinical data of patients enrolled in an ART cohort were collected within 18 months of an observational longitudinal study and analysed by logistic and Cox regression models. RESULTS: Of 159 patients with treatment indication 35 (22%) never started ART. Pregnancy [adjusted odds ratio (AOR) 3.60, 95% confidence interval (CI) 1.10-11.8; P = 0.035] and lower level of education (AOR 3.80, 95% CI 1.14-12.7; P = 0.03) were independently associated with treatment denial. The incidence of total loss of patients under therapy was 43.2 per 100 person years (pys) (mortality rate 19.2 per 100 pys plus drop out rate 24 per 100 pys). Older age [adjusted hazard ratio (AHR) 1.06, 95% CI 1.01-1.12; P = 0.04], AIDS before starting treatment (AHR 5.83, 95% CI 1.15-29.5; P = 0.03) and incomplete adherence to treatment (AHR 1.05, 95% CI 1.03-1.07; P < 0.001) were independent risk factors for death. Incomplete adherence also independently predicted drop out because of other reasons (AHR 1.06, 95% CI 1.04-1.09; P < 0.001). CONCLUSION: Pregnancy and lower level of education, higher age, advanced AIDS stage and impaired compliance to ART were identified as risk factors for treatment denial and death, respectively. Adequate counselling strategies for patients with these characteristics could help to improve adherence and outcome of treatment programmes in resource-limited settings.

Intrapartum transmission after mucosal exposure to HIV was not observed with single-dose nevirapine for mother and child.

BACKGROUND: Intrapartum transmission of HIV has been reported to be associated with HIV in oropharyngeal secretions (OPSs) of the child. In this study, we analyze the frequency of intrapartum transmission after mucosal exposure to HIV after administration of single-dose nevirapine. METHODS: Eighty mothers and their children participating in a prevention of mother-to-child transmission of HIV program in Uganda who took a single dose of nevirapine according to the HIVNET012 protocol participated in the study. HIV-1 was quantified by polymerase chain reaction (PCR) in the mothers' and children's plasma, in cervicovaginal secretions (CVSs), and in the children's OPSs. Intrapartum transmission was defined as a positive HIV-1 RNA PCR result at week 1 or 2 after birth and a previously negative PCR result. RESULTS: Ninety-seven percent of children had detectable nevirapine in their OPS (median = 592 ng/mL). Fifty-seven (81%) children had HIV-negative OPSs, and 13 (19%) had HIV-positive OPSs. All children of mothers with HIV-negative CVSs had HIV-negative OPSs. HIV-1 levels of OPSs and CVSs correlated (r = 0.33, P = 0.027). None of the babies with detectable HIV-1 in the OPSs became infected by means of intrapartum transmission. CONCLUSION: Intrapartum HIV infection was not observed after mucosal exposure to HIV-1 after administration of a single dose of nevirapine to the mother and child.

Outcome of different nevirapine administration strategies in preventing mother-to-child transmission (PMTCT) programs in Tanzania and Uganda.

OBJECTIVE: Prevention-of-mother-to-child transmission (PMTCT) interventions based on single-dose nevirapine (NVP) are widely implemented in Africa, but strategies differ regarding how and when to administer the drug to women and infants. The aim of this study was to analyze the outcome of different strategies with regard to NVP intake in pregnant women and their infants in Tanzania and Uganda. METHODS: In an observational study carried out between March 2002 and December 2004, we compared a directly observed NVP administration strategy in Tanzania (supervised NVP intake for women and infants at a health unit) and a semi-observed administration strategy (self-administered NVP for women at home and supervised intake for infants at a health unit) in Uganda. RESULTS: The proportions of HIV-positive women accepting receipt of NVP from the health units were similar in the 2 countries (42.4% in Tanzania vs 45.6% in Uganda; P = .06). NVP intake in infants was significantly higher in Tanzania than in Uganda (43.7% vs 24.1%; P > .001). In a multivariate analysis, maternal age above 25 years, secondary education, Catholic faith, and having undergone PMTCT counseling at a hospital were independently associated with infant NVP intake. CONCLUSION: In our settings, the directly observed administration strategy resulted in a higher NVP intake in infants. The semi-observed strategy, which implies that, after home delivery, the infant has to be presented to a health unit for NVP administration, was less successful.

Comparison of two alternative methods for CD4+ T-cell determination (Coulter manual CD4 count and CyFlow) against standard dual platform flow cytometry in Uganda.

BACKGROUND: In this study we evaluated alternative CD4(+) T-cell counting methods in clients of a PMTCT Programme in rural Uganda. METHODS: The Coulter Manual CD4 Count method for CD4(+) T-cell enumeration (Cyto-Spheres) and an automated method (volumetric, single-platform flow cytometry; CyFlow) were compared with a standard, dual-platform flow cytometry protocol (DPFC, FACScan). RESULTS: Correlation and precision of agreement were higher for the CyFlow method (r = 0.929 and eta = 0.08) when compared to DPFC than for the Cyto-Spheres method (r = 0.725 and eta = 0.3). Multiple linear regression analysis showed that CD4(+) cell counts by the CyFlow method were a stronger predictor for results of DPFC than those of the Cyto-Spheres method (r(2) = 0.864 and r(2) = 0.552, respectively). When compared to DPFC the CyFlow method generated higher CD4(+) cell counts than the Cyto-Spheres method, as expressed by a higher median and mean difference (+70 and +90 cells for CyFlow, +28 and -1.4 cells for Cyto-Spheres). CONCLUSION: Both, the manual Cyto-Spheres method and the CyFlow method can be used for the enumeration of CD4(+) cells in resource-limited settings. Under supervised conditions, the CyFlow method produced results more consistent with the reference method than the Cyto-Spheres method.

Outcome of Different Nevirapine Administration Strategies in Preventin g Mother-to-Child Transmission (PMTCT) Programs in Tanzania and Uganda.

OBJECTIVE: Prevention-of-mother-to-child transmission (PMTCT) interventions based on single-dose nevirapine (NVP) are widely implemented in Africa, but strategies differ regarding how and when to administer the drug to women and infants. The aim of this study was to analyze the outcome of different strategies with regard to NVP intake in pregnant women and their infants in Tanzania and Uganda. METHODS: In an observational study carried out between March 2002 and December 2004, we compared a directly observed NVP administration strategy in Tanzania (supervised NVP intake for women and infants at a health unit) and a semi-observed administration strategy (self-administered NVP for women at home and supervised intake for infants at a health unit) in Uganda. RESULTS: The proportions of HIV-positive women accepting receipt of NVP from the health units were similar in the 2 countries (42.4% in Tanzania vs 45.6% in Uganda; P = .06). NVP intake in infants was significantly higher in Tanzania than in Uganda (43.7% vs 24.1%; P < .001). In a multivariate analysis, maternal age above 25 years, secondary education, Catholic faith, and having undergone PMTCT counseling at a hospital were independently associated with infant NVP intake. CONCLUSION: In our settings, the directly observed administration strategy resulted in a higher NVP intake in infants. The semi-observed strategy, which implies that, after home delivery, the infant has to be presented to a health unit for NVP administration, was less successful.