Adverse Events in HIV-Infected Persons Receiving Antiretroviral Drug Regimens in a Large Urban Slum in Nairobi, Kenya, 2003-2005.
Author: Kim, A. A.; Wanjiku, L.; Macharia, D. K.; Wangai, M.; Isavwa, A.; Abdi, H.; Marston, B. J.; Ilako, F.; Kjaer, M.; Chebet, K.; De Cock, K. M., and Weidle, P. J.
Source: J Int Assoc Physicians AIDS Care (Chic Ill). 2007 Sep; 6(3):206-9.
Abstract: Objective:
This article describes toxicities to antiretroviral therapy (ART) among HIV-infected patients receiving care at a clinic in a large urban slum in Nairobi, Kenya.
Methods:
Patients were treated with nonnucleoside reverse transcriptase inhibitor-based ART and followed at scheduled intervals. Frequencies and cumulative probabilities of toxicities were calculated.
Results:
Among 283 patients starting ART, any and severe clinical toxicity were recorded as 65% and 6%, respectively. Cumulative probabilities for remaining free of any and severe clinical toxicities at 6, 12, and 18 months, were 0.47, 0.26, and 0.17, respectively and 0.98, 0.95, and 0.89, respectively. The probability of remaining free from elevated and grade 3 or 4 serum aminotransferase (AST) at 6, 12, and 18 months were 0.62, 0.42, and 0.21, respectively, and 0.99 at 6, 12, and 18 months.
Conclusions:
ART toxicities were frequent, but severe toxicities were less common. In resource-limited settings, ART toxicity should not represent a barrier to care.
IL-7Ralpha expression on CD4+ T lymphocytes decreases with HIV disease progression and inversely correlates with immune activation.
Author: Koesters, S. A.; Alimonti, J. B.; Wachihi, C.; Matu, L.; Anzala, O.; Kimani, J.; Embree, J. E.; Plummer, F. A., and Fowke, K. R.
Source: Eur J Immunol. 2006 Feb; 36(2):336-44.
Abstract: Many factors can influence the rate of HIV disease progression, including those that maintain T cell homeostasis. One key homeostatic regulator is the IL-7 receptor (IL-7R). Previous studies have shown IL-7R expression levels decrease in HIV infection, but effects on memory subtypes, CD4(+) T cells, and cell function have not been explored. The present study examined the expression of the IL-7Ralpha chain on naive and memory T lymphocyte subsets of both HIV-positive and HIV-negative individuals from Nairobi, Kenya to assess the role of IL-7Ralpha in HIV disease. Expression of IL-7Ralpha was significantly reduced in all CD4(+) and CD8(+) T cell subsets in HIV-positive individuals. This reduction was further enhanced in those with advanced HIV progression. Expression of IL-7Ralpha was inversely correlated to immune activation, and apoptosis, and was positively correlated with CD4 count in both bivariate and multivariate analysis. Expression of IL-7Ralpha did not correlate with HIV viral loads, indicating the elevated immune activation seen in HIV-infected individuals may be impacting expression of IL-7Ralpha, independent of viral loads. Signaling via the IL-7R is essential for T cell homeostasis and maintenance of T cell memory. Reduction of this receptor may contribute to the homeostatic disruption seen in HIV.
Social networks and HIV/AIDs risk perceptions.
Author: Kohler, H. P.; Behrman, J. R., and Watkins, S. C.
Source: Demography. 2007 Feb; 44(1):1-33.
Abstract: Understanding the determinants of individuals' perceptions of their risk of becoming infected with HIV and their perceptions of acceptable strategies of prevention is an essential step toward curtailing the spread of this disease. We focus in this article on learning and decision-making about AIDS in the context of high uncertainty about the disease and appropriate behavioral responses. We argue that social interactions are important for both. Using longitudinal survey data from rural Kenya and Malawi, we test this hypothesis. We investigate whether social interactions--and especially the extent to which social network partners perceive themselves to be at risk--exert causal influences on respondents' risk perceptions and on one approach to prevention, spousal communication about the threat of AIDS to the couple and their children. The study explicitly allows for the possibility that important characteristics, such as unobserved preferences or community characteristics, determine not only the outcomes of interest but also the size and composition of networks. The most important empirical result is that social networks have significant and substantial effects on risk perceptions and the adoption of new behaviors even after we control for unobserved factors.
Etiology and resistance patterns of respiratory isolates in Kenyan adults with AIDS from slum population.
Author: Krcmery, V.; Benca, J.; Liskova, A.; Mitterpachova, E.; Kolenova, A.; Sladeckova, V.; Horvathova, D., and Kiwou, M.
Source: Neuro Endocrinol Lett. 2007 Nov; 28 Suppl 3:37-9.
Abstract: We investigated regularly swabs of adults dispenzarised at Mary Immaculate Clinic of Trnava University in Nairobi providing free health care for about 50 000 population of Mukuru Slums. 20 patients who were treated for AIDS by our clinic (those who started HAART before Free National AIDS Cooperation Programme - NASCOP) were assessed after 1, 2 and 3 years (18 of 20 completed the survey, other 2 loss of follow up, probably died. Exposure to other molecules can select resistant mutants. Previous exposure to TMP/SMX was similar in both groups and therefore was not responsible for the difference between resistance patterns.
Adult male circumcision: results of a standardized procedure in Kisumu District, Kenya.
Author: Krieger, J. N.; Bailey, R. C.; Opeya, J.; Ayieko, B.; Opiyo, F.; Agot, K.; Parker, C.; Ndinya-Achola, J. O.; Magoha, G. A., and Moses, S.
Source: BJU Int. 2005 Nov; 96(7):1109-13.
Abstract: Objective:
To develop a standard procedure for male circumcision in a resource-poor medical setting and prospectively evaluate the outcome in a randomized, controlled trial with the incidence of human immunodeficiency virus (HIV) as the main outcome, as studies suggest that circumcision is associated with a lower incidence of HIV and other sexually transmitted infections in high-risk populations.
Subjects and methods:
Healthy, uncircumcised, HIV-seronegative men aged 18-24 years from Kisumu District, Kenya, were offered participation in a clinical trial using a standard circumcision procedure based on "usual" medical procedures in Western Kenya. The follow-up included visits at 3, 8 and 30 days after circumcision, with additional visits if necessary. Healing, satisfaction and resumption of activities were assessed at these visits and 3 months from randomization.
Results:
Overall, 17 (3.5%) of the 479 circumcisions were associated with adverse events judged definitely, probably or possibly related to the procedure. The most common adverse events were wound infections (1.3%), bleeding (0.8%), and delayed wound healing or suture line disruption (0.8%). After 30 days, 99% of participants reported being very satisfied with the procedure; approximately 23% reported having had sex and 15% reported that their partners had expressed an opinion, all of whom were very satisfied with the outcome. About 96% of the men resumed normal general activities within the first week after the procedure.
Conclusion:
Safe and acceptable adult male circumcision services can be delivered in developing countries should male circumcision ultimately be advocated as a public-health measure.
Associations of human leukocyte antigen DRB with resistance or susceptibility to HIV-1 infection in the Pumwani Sex Worker Cohort.
Author: Lacap, P. A.; Huntington, J. D.; Luo, M.; Nagelkerke, N. J.; Bielawny, T.; Kimani, J.; Wachihi, C.; Ngugi, E. N., and Plummer, F. A.
Source: AIDS. 2008 May 31; 22(9):1029-38.
Abstract: Objective:
A group of commercial sex workers in the Pumwani Sex Worker Cohort, established in 1985 in Nairobi, Kenya, remain HIV-1 uninfected despite heavy exposure to HIV-1 through active sex work. Previous studies showed that this resistance is associated with a strong CD4+ T-cell response, which suggested that human leukocyte antigen class II antigens are important in resistance/susceptibility to HIV-1 infection. DRB1 is the most polymorphic locus among class II genes and forms haplotypes with DRB3, DRB4 and DRB5. The aim of this study is to investigate the role of DRB alleles/haplotypes on resistance/susceptibility to HIV-1 infection.
Design:
In total, 1090 women enrolled in the Pumwani cohort were genotyped for DRB1, DRB3, DRB4 and DRB5 using a high-resolution sequence-based method. Allele/haplotype frequencies were compared between HIV-positive women and women who have remained HIV negative for more than 3 years despite frequent exposure.
Methods:
Human leukocyte antigen DRB genes were amplified, sequenced and genotyped using a two-step sequence-based method. Allele/haplotype frequencies were determined using PyPop32-0.6.0. Statistical analysis was conducted using SPSS 11.0 for Windows.
Results:
Three DRB1 alleles were associated with resistance: DRB1*010101 (P = 0.016; odd ratio (OR): 2.55; 95% confidence interval (CI): 1.16-5.61), DRB1*010201 (P = 0.019; OR: 1.86; 95% CI: 1.10-3.15), and DRB1*1102 (P = 0.025; OR: 1.72; 95% CI: 1.07-2.78). DRB1*030201 (P = 0.038; OR: 0.48; 95% CI: 0.23-0.98), DRB1*070101 (P = 0.035; OR: 0.54; 95% CI: 0.30-0.97), DRB1*1503 (P = 0.0004; OR: 0.34; 95% CI: 0.19-0.64), and DRB5*010101 (P = 0.001; OR: 0.37; 95% CI: 0.20-0.67) were associated with susceptibility. The haplotype DRB1*1102-DRB3*020201 was associated with HIV-1 resistance (P = 0.041; OR: 1.68; 95% CI: 1.02-2.78), whereas the haplotypes DRB1*070101-DRB4*01010101 (P = 0.041; OR: 0.52; 95% CI: 0.28-0.98) and DRB1*1503-DRB5*01010101 (P = 0.0002; OR: 0.30; 95% CI: 0.15-0.58) were associated with susceptibility. These associations with resistance/susceptibility to HIV-1 were independent of previously reported alleles HLA-DRB1*01 and HLA-A*2301.
Conclusion:
Our findings indicate that human leukocyte antigen DRB-specific CD4+ T-cell responses are an important factor in resistance/susceptibility to HIV-1 infection.
Human immunodeficiency virus (HIV) type 1 proviral hypermutation correlates with CD4 count in HIV-infected women from Kenya.
Author: Land, A. M.; Ball, T. B.; Luo, M.; Pilon, R.; Sandstrom, P.; Embree, J. E.; Wachihi, C.; Kimani, J., and Plummer, F. A.
Source: J Virol. 2008 Aug; 82(16):8172-82.
Abstract: APOBEC3G is an important innate immune molecule that causes human immunodeficiency virus type 1 (HIV-1) hypermutation, which can result in detrimental viral genome mutations. The Vif protein of wild-type HIV-1 counteracts APOBEC3G activity by targeting it for degradation and inhibiting its incorporation into viral particles. Additional APOBEC cytidine deaminases have been identified, such as APOBEC3F, which has a similar mode of action but different sequence specificity. A relationship between APOBEC3F/G and HIV disease progression has been proposed. During HIV-1 sequence analysis of the vpu/env region of 240 HIV-infected subjects from Nairobi, Kenya, 13 drastically hypermutated proviral sequences were identified. Sequences derived from plasma virus, however, lacked hypermutation, as did proviral vif. When correlates of disease progression were examined, subjects with hypermutated provirus were found to have significantly higher CD4 counts than the other subjects. Furthermore, hypermutation as estimated by elevated adenine content positively correlated with CD4 count for all 240 study subjects. The sequence context of the observed hypermutation was statistically associated with APOBEC3F/G activity. In contrast to previous studies, this study demonstrates that higher CD4 counts correlate with increased hypermutation in the absence of obvious mutations in the APOBEC inhibiting Vif protein. This strongly suggests that host factors, such as APOBEC3F/G, are playing a protective role in these patients, modulating viral hypermutation and host disease progression. These findings support the potential of targeting APOBEC3F/G for therapeutic purposes.
Full-length HIV type 1 proviral sequencing of 10 highly exposed women from Nairobi, Kenya reveals a high proportion of intersubtype recombinants.
Author: Land, A. M.; Ball, T. B.; Luo, M.; Rutherford, J.; Sarna, C.; Wachihi, C.; Kimani, J., and Plummer, F. A.
Source: AIDS Res Hum Retroviruses. 2008 Jun; 24(6):865-72.
Abstract: Phylogenetic analysis has revealed that the current HIV/AIDS pandemic consists of a multitude of different viral clades and recombinant viruses. The predominant circulating HIV-1 clade in Kenya is A1; however, Kenya borders countries where different subtypes are prominent, making Kenya a likely location for recombination. Previous studies have reported significant differences in the proportions of sequences in Kenya that are intersubtype recombinants. Studies that performed sequence-based typing on multiple HIV-1 genomic regions or full-length sequences found higher rates of recombination than those that examined a single gene or gene fragment. In this study, we describe full-length HIV-1 proviral sequence-based genotyping after limited peripheral blood mononuclear cell (PBMC) coculture. Ten subjects from a highly exposed cohort located in Nairobi, Kenya were examined. Pairwise comparison found minimal difference between sequences generated directly from patient PBMC DNA compared to sequences from cocultured PBMC DNA. Of the 10 full-length HIV-1 sequences examined, five were nonrecombinant clade A1, while the other five were unique intersubtype recombinants. Although this frequency of recombination is higher than previously described in Kenya, this finding is in agreement with previous full-length sequence data. Interestingly, although all the nonrecombinant sequences were clade A1, not all the recombinant sequences contained a clade A1 sequence.
Effects of antiretroviral therapy on work performance: preliminary results from a cohort study of Kenyan agricultural workers.
Author: Larson, B. A.; Fox, M. P.; Rosen, S.; Bii, M.; Sigei, C.; Shaffer, D.; Sawe, F.; Wasunna, M., and Simon, J. L.
Source: AIDS. 2008 Jan 30; 22(3):421-5.
Abstract: Objective:
This paper estimates the impact of antiretroviral therapy (ART) on days harvesting tea per month for tea-estate workers in Kenya. Such information is needed to assess the potential economic benefits of providing treatment to working adults.
Methods:
Data for this analysis come from company payroll records for 59 HIV-infected workers and a comparison group of all workers assigned to the same work teams (reference group, n = 1992) for a period covering 2 years before and 1 year after initiating ART. Mean difference tests were used to obtain overall trends in days harvesting tea by month. A difference in difference approach was used to estimate the impact of HIV/AIDS on days working in the pre-ART period. Information on likely trends in the absence of the therapy was used to estimate the positive impacts on days harvesting tea over the initial 12 months on ART.
Results:
No significant difference existed in days plucking tea each month until the ninth month before initiating ART, when workers worked -2.79 fewer days than references (15% less). This difference grew to 5.09 fewer days (27% less) in the final month before initiating ART. After 12 months on ART, we conservatively estimate that workers worked at least twice as many days in the month than they would have in the absence of ART.
Conclusions:
Treatment had a large, positive impact on the ability of workers to undertake their primary work activity, harvesting tea, in the first year on ART.
Higher set point plasma viral load and more-severe acute HIV type 1 (HIV-1) illness predict mortality among high-risk HIV-1-infected African women.
Author: Lavreys, L.; Baeten, J. M.; Chohan, V.; McClelland, R. S.; Hassan, W. M.; Richardson, B. A.; Mandaliya, K.; Ndinya-Achola, J. O., and Overbaugh, J.
Source: Clin Infect Dis. 2006 May 1; 42(9):1333-9.
Abstract: Background:
There is limited information on the natural history of human immunodeficiency virus type 1 (HIV-1) infection in Africa, especially from individuals with well-defined dates of infection. We used data from a prospective cohort study of female sex workers in Mombasa, Kenya, who were followed up monthly from before the date of HIV-1 infection.
Methods:
Antiretroviral-naive women who had a well-defined date of HIV-1 infection were included in this analysis. The effects of set point plasma viral load (measured 4-24 months after infection), early CD4+ cell count, and symptoms of acute HIV-1 infection on mortality were assessed using Cox proportional hazards analysis.
Results:
Among 218 women, the median duration of follow-up after HIV-1 infection was 4.6 years. Forty women died, and at 8.7 years (the time of the last death), the cumulative survival rate was 51% by Kaplan-Meier analysis. Higher set point viral load, lower early CD4+ cell count, and more-symptomatic acute HIV-1 illness each predicted death. In multivariate analysis, set point viral load (hazard ratio [HR], 2.28 per 1 log10 copies/mL increase; P=.001) and acute HIV-1 illness (HR, 1.14 per each additional symptom; P=.05) were independently associated with higher mortality.
Conclusion:
Among this group of African women, the survival rate was similar to that for HIV-1-infected individuals in industrialized nations before the introduction of combination antiretroviral therapy. Higher set point viral load and more-severe acute HIV-1 illness predicted faster progression to death. Early identification of individuals at risk for rapid disease progression may allow closer clinical monitoring, including timely initiation of antiretroviral treatment.
Commercial sex and HIV transmission in mature epidemics: a study of five African countries.
Author: Leclerc, P. M. and Garenne, M.
Source: Int J STD AIDS. 2008 Oct; 19(10):660-4.
Abstract: The study compares the association between using the services of commercial sex workers and male HIV seroprevalence in five African countries: Ghana, Kenya, Lesotho, Malawi and Rwanda. The HIV seroprevalence among men who 'ever paid for sex' was compared with controls who 'never paid for sex'. Results were based on 12,929 eligible men, aged 15-59 years, interviewed in Demographic and Health Surveys. The odds ratio of HIV seroprevalence associated with ever paying for sex was 1.89 (95% confidence interval = 1.57-2.28), with only minor differences by country. The results were stable in multivariate analysis after controlling for available potential cofactors (data on non-sexual routes of transmission were not available). Given the relatively small proportion of men involved, the risk attributable to 'ever paying for sex' remained low: 7.1% in univariate analysis and 4.4% after adjustment, and it varied among countries (range 1.3-9.4%). These results match previous observations that commercial sex seems to play a minor role in the spread of HIV in mature epidemics.
Toll-like receptor expression and responsiveness are increased in viraemic HIV-1 infection.
Author: Lester, R. T.; Yao, X. D.; Ball, T. B.; McKinnon, L. R.; Kaul, R.; Wachihi, C.; Jaoko, W.; Plummer, F. A., and Rosenthal, K. L.
Source: AIDS. 2008 Mar 30; 22(6):685-94.
Abstract: Objectives:
Toll-like receptors (TLR) are important in pathogen recognition and may play a role in HIV disease. We evaluated the effect of chronic untreated and treated HIV-1 infection on systemic TLR expression and TLR signalling. METHODS: Two hundred HIV-infected and uninfected women from a Kenya cohort participated in the studies. TLR1 to TLR10 messenger RNA expression was determined by quantitative reverse transcriptase polymerase chain reaction in peripheral blood mononuclear cells (PBMC). TLR ligand responsiveness was determined in or using ex-vivo PBMC by cytokine production in culture supernatants.
Results:
Chronic, untreated HIV-1 infection was significantly associated with increased mRNA expression of TLR6, TLR7, and TLR8 and when analysis was limited to those with advanced disease (CD4 cell count < 200 cells/ml) TLR2, TLR3, and TLR4 were additionally elevated. TLR expression correlated with the plasma HIV-RNA load, which was significant for TLR6 and TLR7. In vitro HIV single-stranded RNA alone could enhance TLR mRNA expression. PBMC of HIV-infected subjects also demonstrated profoundly increased proinflammatory responsiveness to TLR ligands, suggesting sensitization of TLR signalling in HIV. Finally, viral suppression by HAART was associated with a normalization of TLR levels.
Conclusion:
Together, these data indicate that chronic viraemic HIV-1 is associated with increased TLR expression and responsiveness, which may perpetuate innate immune dysfunction and activation that underlies HIV pathogenesis, and thus reveal potential new targets for therapy
HIV type 1 subtypes among STI patients in Nairobi: a genotypic study based on partial pol gene sequencing.
Author: Lihana, R. W.; Khamadi, S. A.; Kiptoo, M. K.; Kinyua, J. G.; Lagat, N.; Magoma, G. N.; Mwau, M. M.; Makokha, E. P.; Onyango, V.; Osman, S.; Okoth, F. A., and Songok, E. M.
Source: IDS Res Hum Retroviruses. 2006 Nov; 22(11):1172-7.
Abstract: Circulating strains of human immunodeficiency virus (HIV) exhibit an extraordinary degree of genetic diversity and have been classified on the basis of relationships into distinct lineages called groups, types, subtypes, and subsubtypes. Sexually transmitted infections (STIs) are known to be a risk factor for HIV infection. To establish HIV-1 subtype diversity among STI patients in Nairobi, 140 samples were collected and partial pol gene sequencing done. From the analysis it was established that subtype A1 was the major subtype (64%) followed by D (17%), C (9%), G (1%), and recombinants AD (4%), AC (3%), CRF02()AG (1%), and CRF16()A2D (1%). These results suggest that the HIV-1 epidemic may be evolving toward more virulent and complex subtypes through transmission of complex recombinants due to viral mixing. Any use of ARVs may therefore require initial testing for de novo resistance before commencement of treatment and/or management.
Longitudinal assessment of human immunodeficiency virus type 1 (HIV-1)-specific gamma interferon responses during the first year of life in HIV-1-infected infants.
Author: Lohman, B. L.; Slyker, J. A.; Richardson, B. A.; Farquhar, C.; Mabuka, J. M.; Crudder, C.; Dong, T.; Obimbo, E.; Mbori-Ngacha, D.; Overbaugh, J.; Rowland-Jones, S., and John-Stewart, G.
Source: J Virol. 2005 Jul; 79(13):8121-30.
Abstract: Human immunodeficiency virus type 1 (HIV-1) infection results in different patterns of viral replication in pediatric compared to adult populations. The role of early HIV-1-specific responses in viral control has not been well defined, because most studies of HIV-1-infected infants have been retrospective or cross-sectional. We evaluated the association between HIV-1-specific gamma interferon (IFN-gamma) release from the cells of infants of 1 to 3 months of age and peak viral loads and mortality in the first year of life among 61 Kenyan HIV-1-infected infants. At 1 month, responses were detected in 7/12 (58%) and 6/21 (29%) of infants infected in utero and peripartum, respectively (P = 0.09), and in approximately 50% of infants thereafter. Peaks of HIV-specific spot-forming units (SFU) increased significantly with age in all infants, from 251/10(6) peripheral blood mononuclear cells (PBMC) at 1 month of age to 501/10(6) PBMC at 12 months of age (P = 0.03), although when limited to infants who survived to 1 year, the increase in peak HIV-specific SFU was no longer significant (P = 0.18). Over the first year of life, infants with IFN-gamma responses at 1 month had peak plasma viral loads, rates of decline of viral load, and mortality risk similar to those of infants who lacked responses at 1 month. The strength and breadth of IFN-gamma responses at 1 month were not significantly associated with viral containment or mortality. These results suggest that, in contrast to HIV-1-infected adults, in whom strong cytotoxic T lymphocyte responses in primary infection are associated with reductions in viremia, HIV-1-infected neonates generate HIV-1-specific CD8+-T-cell responses early in life that are not clearly associated with improved clinical outcomes.
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