Assessment of Risk Predisposition to Human Papilloma Virus through Cervical Infections Screening of Women Attending an Outpatient Health Facility in Nairobi, Kenya

There is limited data on comparative disposition to cervical cancer among HPV infected women in Kenya. We aimed to determine the distribution of HPV infection, cervical abnormalities and infections commonly reported on cervical pap smears among both HIV positive and HIV negative women attending a reproductive health clinic at the largest national hospital in Kenya. A total of 187 women aged 18 to 50 years attending the reproductive clinic at Kenyatta National Referral Hospital in Nairobi were recruited into the study. All consenting subjects were screened for HIV by serology and their cervical smears taken and immediately fixed on slides for Papanicolaou (Pap) staining. A second endocervical swab was collected in the same sitting for HPV DNA extraction and PCR amplification of the HPV LI region.  Of the 187 women studied, 27 (14.4 %) were positive for HIV and 90 (48.1%) had one or more infection associated with bacterial vaginosis, candidiasis, cervicitis or inflammation of the cervix of unknown cause.  Eight (4.3%) women had abnormal cervix, 3/8 being of high grade squamous intraepithelial lesions (HSIL), 1/8 of low grade squamous intraepithelial lesions (LSIL), 1/8 had adenocarcinoma while the remaining 3 had atypical squamous cells of undetermined significance (ASC-US). The remaining 89/187 (47.6%) women had normal smears with no infection. Of the 89 women with normal smears, 82 (92.1%) were HIV negative.  A total of 66 (35.3%) women were positive for HPV L1 DNA by PCR and included 30 of the 89 women with normal cytology. Of the 27 HIV positive women, 14 (51.9%) were also positive for HPV LI DNA. 52 of the 160 (32.5%) HIV negative women were positive for HPV L1 DNA. We report more cases of cervical intraepithelial lesions among HIV positive than HIV negative women. Similarly, the other infections commonly found on Pap smear tests were higher among HIV negative than HIV positive women. HPV prevalence among these clinic-attending women was higher in those with normal cytology, indicating an increased underlying risk of cervical cancer in a setting where routine diagnostic screening is limited or non-existent. Keywords: cervical cancer, HIV, HPV, cervical cytolog

Mucosal prior to systemic application of recombinant adenovirus boosting is more immunogenic than systemic application twice but confers similar protection against SIV-challenge in DNA vaccine-primed macaques

AbstractWe investigated the immunogenicity and efficacy of a bimodal prime/boost vaccine regimen given by various routes in the Simian immunodeficiency virus (SIV) rhesus monkey model for AIDS. Twelve animals were immunized with SIV DNA-vectors followed by the application of a recombinant adenovirus (rAd5) expressing the same genes either intramuscularly (i.m.) or by oropharyngeal spray. The second rAd5-application was given i.m. All vaccinees plus six controls were challenged orally with SIVmac239 12 weeks post-final immunization.Both immunization strategies induced strong SIV Gag-specific IFN-γ and T-cell proliferation responses and mediated a conservation of CD4+ memory T-cells and a reduction of viral load during peak viremia following infection. Interestingly, the mucosal group was superior to the systemic group regarding breadth and strength of SIV-specific T-cell responses and exhibited lower vector specific immune responses. Therefore, our data warrant the inclusion of mucosal vector application in a vaccination regimen which makes it less invasive and easier to apply

HIV-1 Coreceptor Tropism among Kenyans Under Highly Active Antiretroviral Therapy.

Despite the scale up of the use of combined highly active antiretroviral (ARV) therapy, many HIV-1 infected patients are still failing treatment in Kenya. In 2007, the Food Drug and Administration (FDA) approved the use of CCR5 antagonists in treatment experienced patients. CCR5 antagonists work by inhibiting the entry of HIV-1 that uses CCR5 as a coreceptor to gain entry into cells. CCR5 59029 A/G (promoter region—rs1799987) is a polymorphism that leads to the upregulation of the expression of the CCR5 protein thereby affecting the rate of HIV-1 infection. The use of these CCR5 antagonists in Kenya is limited partly because of minimal data on host genetics and coreceptor tropism among HIV-1 infected patients. In this study, we aimed at determining the prevalence of CCR5 tropic variants and CCR5 59029AG promoter polymorphism known to influence HIV-1 infection. We sequenced the V3 region of the env gene and inferred the HIV-1 tropism using clonal model of Geno2Pheno algorithm (FPR= 5%).   Also, we assessed the frequency of the CCR5 promoter polymorphisms among the patients by sequencing the polymorphic region of the CCR5 promoter. Majority of the patients (77.27%) had R5 tropic viruses whereas 22.73% of the study subjects had detectable CCR4 using viruses. The frequencies of the CCR5 59029 AA, AG, and GG genotypes were 14 (31.82%), 9 (20.45%) and 21(47.73%), respectively. Taken together, these results indicate that CCR5 antagonists could have potential therapeutic effects in the clinical management of HIV-1 among the infected patients in Kenya. Key words: CCR5 antagonists, CCR5 59029AG, HAART, HIV-1, Polymorphism, Tropis

Efficient monitoring of HIV-1 vertically infected children in Kenya on first-line antiretroviral therapy

Background: Worldwide access to antiretroviral therapy (ART) in low- and middle-income countries has significantly increased. Although this presents better treatment options for HIV-infected individuals, the challenge of monitoring ART in these settings still remains. Objective: To investigate efficient and cost-effective criteria for assessing ART failure among HIV-1-infected children on first-line ART in resource-limited settings. Study design: Retrospective analysis of 75 HIV-1 vertically infected Kenyan children with a follow-up period of 24 months after initiating ART. Plasma viral load, peripheral CD4+T-cell counts and HIV-1 drug-resistance mutations were monitored biannually. Results: Plasma viral load (VL) was suppressed to undetectable level or more than 1.5 log10 from baseline levels in 53 (70.7%) children within 24 months. VL in the remaining 22 (29.3%) children was not suppressed significantly. Of the 22 children, 21 were infected with HIV-1 strains that developed drug-resistance mutations; 9 within 12 months and 12 between 12 and 24 months. Among the 53 who were successfully treated, VL was suppressed in 33 within 12 months and in 20 between 12 and 24 months. There was no significant difference in VL at baseline and the change of CD4+T-cell counts after initiating ART between those treated successfully and the failure groups. Conclusion: After initiating ART, children may require longer times to achieve complete viral suppression. Plasma viral load testing 24 months after initiating ART could be used to differentiate ART failures among HIV-1 vertically infected children in resource-limited settings. Additionally, drug resistance testing, if affordable, would be helpful in identifying those failing therapy and in choosing second-line regimens. © 2011 Elsevier B.V. All rights reserved

Anti-retroviral drug resistance-associated mutations among non-subtype B HIV-1-infected Kenyan children with treatment failure

金沢大学大学院医学系研究科感染症制御学Recently increased availability of antiretroviral therapy (ART) has mitigated HIV-1/AIDS prognoses especially in resource poor settings. The emergence of ART resistance-associated mutations from non-suppressive ART has been implicated as a major cause of ART failure. Reverse transcriptase inhibitor (RTI)-resistance mutations among 12 non-subtype B HIV-1-infected children with treatment failure were evaluated by genotypically analyzing HIV-1 strains isolated from plasma obtained between 2001 and 2004. A region of pol-RT gene was amplified and at least five clones per sample were analyzed. Phylogenetic analysis revealed HIV-1 subtype A1 (n = 7), subtype C (n = 1), subtype D (n = 3), and CRF02_AG (n = 1). Before treatment, 4 of 12 (33.3%) children had primary RTI-resistance mutations, K103N (n = 3, ages 5-7 years) and Y181C (n = 1, age 1 year). In one child, K103N was found as a minor population (1/5 clones) before treatment and became major (7/7 clones) 8 months after RTI treatment. In 7 of 12 children, M184V appeared with one thymidine-analogue-associated mutation (TAM) as the first mutation, while the remaining 5 children had only TAMs appearing either individually (n = 2), or as TAMs 1 (M41L, L210W, and T215Y) and 2 (D67N, K70R, and K219Q/E/R) appearing together (n = 3). These results suggest that "vertically transmitted" primary RTI-resistance mutations, K103N and Y181C, can persist over the years even in the absence of drug pressure and impact RTI treatment negatively, and that appearing patterns of RTI-resistance mutations among non-subtype B HIV-1-infected children could possibly be different from those reported in subtype B-infected children. © 2007 Wiley-Liss, Inc

Viral load, CD4+ T-lymphocyte counts and antibody titres in HIV-1 infected untreated children in Kenya; implication for immunodeficiency and AIDS progression

BACKGROUND: There are limited reports on HIV-1 RNA load, CD4+T-lymphocytes and antibody responses in relation to disease progression in HIV-1 infected untreated children in Africa. METHODS: To describe the relationships between these parameters, we conducted a longitudinal cohort study involving 51 perinatally HIV-1 infected children aged between 1 and 13 years. HIV status was determined by ELISA and confirmed by western blot and PCR. Antibodies were quantified by limiting dilution ELISA, plasma HIV-1 RNA load by RT-PCR and CD4+T-lymphocytes by FACSCount. RESULTS: Asymptomatic and symptomatic disease had, respectively, a rise in median HIV-1 RNA load from 1,195 to 132,543 and from 42,962 to 1,109,281 copies/ml in children below 6 years. The increase in viral load was 10-fold higher for asymptomatic compared to other categories and 2-fold faster for children less than 6 years than those above. Similarly, symptomatic children below 6 years had initial median CD4+T-lymphocyte counts of 647 (22%) cells/µL, declining to 378 (20%) while those above 6 years had initial values of below 335 (15%) but which increased to 428 (17%). Median viral load correlated significantly with median CD4+T-lymphocyte percentage in children above 6 years (p=0.026) but not below. CONCLUSIONS: Viral load is lower in older than younger children and correlates significantly with percentage CD4+T-lymphocytes. Survival by HIV-1 infected children requires a competent immune response early in infection to counter the rapidly replicating virus. Interventions aimed at boosting the naïve immune system may prolong survival in these children