10 research outputs found

    A retrospective evaluation of proficiency testing, and rapid HIV test kits stock-outs among HTC facilities within Nairobi county

    Get PDF
    Background: Proficiency testing (PT) has been implemented as a form of External Quality Assurance (EQA) by the National HIV Reference Laboratory in Kenya since 2007 in order to monitor and improve on the quality of HIV testing and counselling HTC services.Objective: To compare concordance between National HIV Reference laboratory, and HIV testing and counseling (HTC) facilities.Design: A telephone survey was conducted to access consistencies in PT schemes. An independent EQA assessment questionnaire was developed and pretested on a randomly chosen sample of HTC facilities.Setting: HTC facilities selected from Client-initiated HTC and Provider initiated HTC facilities, within Nairobi County.Subjects: The HTC facilities were randomly selected (n = 45).Results: Inconsistencies and tremendous increase in non-participation in PT schemes. Gender χ² (5, N = 45) = 13.83; p= .017, experience using rapid test kits χ² (5, N =45) = 5.417; p = .020, and current facility ever participating in any PT scheme χ² (5, N = 45) = 15.38, p= .009, had significant effects in participation in PT schemes. Some facilities experienced test kits stock-outs most of the time (2.552 ≥ 3.777), while others sometimes (1.326 ≥ 2.551), t (43) =3.105; p= 0.003. However, there was no link between non participation in PT schemes and test kits stock-outs.Conclusion: The results generated by the study revealed inconsistencies in PT schemes and Test Kits stock-outs from 2012 up to May 2014. These findings will assist in the full adoption of HTC policy guidelines and ensure each and every HTC personnel participate in all PT quarters consistently. Challenges in forecasting, and quantification remains a major barrier to HTC supplies

    HIV-1 subtype and viral tropism determination for evaluating antiretroviral therapy options: an analysis of archived Kenyan blood samples

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Infection with HIV-1 is characterized by genetic diversity such that specific viral subtypes are predominant in specific geographical areas. The genetic variation in HIV-1 <it>pol </it>and <it>env </it>genes is responsible for rapid development of resistance to current drugs. This variation has influenced disease progression among the infected and necessitated the search for alternative drugs with novel targets. Though successfully used in developed countries, these novel drugs are still limited in resource-poor countries. The aim of this study was to determine HIV-1 subtypes, recombination, dual infections and viral tropism of HIV-1 among Kenyan patients prior to widespread use of antiretroviral drugs.</p> <p>Methods</p> <p>Remnant blood samples from consenting sexually transmitted infection (STI) patients in Nairobi were collected between February and May 2001 and stored. Polymerase chain reaction and cloning of portions of HIV-1 <it>gag</it>, <it>pol </it>and <it>env </it>genes was carried out followed by automated DNA sequencing.</p> <p>Results</p> <p>Twenty HIV-1 positive samples (from 11 females and 9 males) were analyzed. The average age of males (32.5 years) and females (26.5 years) was significantly different (p value < 0.0001). Phylogenetic analysis revealed that 90% (18/20) were concordant HIV-1 subtypes: 12 were subtype A1; 2, A2; 3, D and 1, C. Two samples (10%) were discordant showing different subtypes in the three regions. Of 19 samples checked for co-receptor usage, 14 (73.7%) were chemokine co-receptor 5 (CCR5) variants while three (15.8%) were CXCR4 variants. Two had dual/mixed co-receptor use with X4 variants being minor population.</p> <p>Conclusion</p> <p>HIV-1 subtype A accounted for majority of the infections. Though perceived to be a high risk population, the prevalence of recombination in this sample was low with no dual infections detected. Genotypic co-receptor analysis showed that most patients harbored viruses that are predicted to use CCR5.</p

    Genetic Analysis of HIV-1 Subtypes in Nairobi, Kenya

    Get PDF
    Background: Genetic analysis of a viral infection helps in following its spread in a given population, in tracking the routes of infection and, where applicable, in vaccine design. Additionally, sequence analysis of the viral genome provides information about patterns of genetic divergence that may have occurred during viral evolution. Objective: In this study we have analyzed the subtypes of Human Immunodeficiency Virus -1 (HIV-1) circulating in a diverse sample population of Nairobi, Kenya. Methodology: 69 blood samples were collected from a diverse subject population attending the Aga Khan University Hospital in Nairobi, Kenya. Total DNA was extracted from peripheral blood mononuclear cells (PBMCs), and used in a Polymerase Chain Reaction (PCR) to amplify the HIV gag gene. The PCR amplimers were partially sequenced, and alignment and phylogenetic analysis of these sequences was performed using the Los Alamos HIV Database. Results: Blood samples from 69 HIV-1 infected subjects from varying ethnic backgrounds were analyzed. Sequence alignment and phylogenetic analysis showed 39 isolates to be subtype A, 13 subtype D, 7 subtype C, 3 subtype AD and CRF01_AE, 2 subtype G and 1 subtype AC and 1 AG. Deeper phylogenetic analysis revealed HIV subtype A sequences to be highly divergent as compared to subtypes D and C. Conclusion: Our analysis indicates that HIV-1 subtypes in the Nairobi province of Kenya are dominated by a genetically diverse clade A. Additionally, the prevalence of highly divergent, complex subtypes, intersubtypes, and the recombinant forms indicates viral mixing in Kenyan population, possibly as a result of dual infections

    High transcript levels of vitamin D receptor are correlated with higher mRNA expression of human beta defensins and IL-10 in mucosa of HIV-1-exposed seronegative individuals

    Get PDF
    RESUMEN: La vitamina D (VitD) es un inmunomodulador endógena que podría proteger de la infección por VIH-1 la reducción de la activación inmune y la inducción de la expresión de VIH-1 anti-péptidos. Para establecer una correlación entre VitD y resistencia natural a la infección VIH-1, un estudio de casos y controles utilizando sangre y mucosa muestras de 58 VIH-1 expuesto, pero seronegativos (HESN) individuos , 43 VIH-1 seropositivos (SP) y 59 no controles sanos -exposed (HCS) se llevó a cabo. La concentración VitD en el plasma se determinó por ELISA, y de ARNm de unidades relativas (RU) de VDR, IL-10 , TGF-β, TNF-α e IL-1β en las células mononucleares de sangre periférica (PBMCs), oral y genital mucosa se cuantificó por QRT-PCR. mRNA niveles de humana beta -defensin (HBD) -2 y -3 se informó anteriormente y utilizados para correlaciones. Significativamente más altos niveles de VitD se encontraron en plasma, así como mayor mRNA RU de VDR en PBMCs, y en genital mucosa de HESN en comparación con HC. Además, superior mRNA RU de TNF-α, IL-1β y IL-10 , e inferior mRNA RU de TGF-β se encontraron en PBMC de HESNs en comparación con HC. También se observó mayor IL-10 mRNA RU en genital mucosa de HESNs en comparación con HC, y los ARNm de los niveles de TNF-α en oral y genital mucosa de SPs estábamos más alta en comparación con HESNs. Por otra parte, las correlaciones positivas entre VDR y la IL-10 mRNA RU en PBMCs y genital mucosa encontrados de HESNs. Por último, HBD-2 y HBD-3 ARNm RU fueron positivamente correlacionadas con VDR mRNA expresión en forma oral mucosa de HESNs. Estos resultados sugieren que los altos niveles de VitD y su receptor están asociadas con resistencia natural a la infección por VIH-1. Sobre regulación de los anti-inflamatoria IL-10 , y la inducción de anti-VIH-1 defensinas en la mucosa podría ser parte de los mecanismos implicados en esta asociación. Sin embargo, se necesitan más estudios para definir las asociaciones causales.ABSTRACT: Vitamin D (VitD) is an endogenous immunomodulator that could protect from HIV-1 infection reducing immune activation and inducing the expression of anti-HIV-1 peptides. To establish a correlation between VitD and natural resistance to HIV-1 infection, a case-control study using blood and mucosa samples of 58 HIV-1-exposed but seronegative (HESN) individuals, 43 HIV-1 seropositives (SPs) and 59 non-exposed healthy controls (HCs) was carried out. The VitD concentration in plasma was determined by ELISA, and mRNA relative units (RU) of VDR, IL-10, TGF-β, TNF-α and IL-1β in peripheral blood mononuclear cells (PBMCs), oral and genital mucosa was quantified by qRT-PCR. mRNA levels of human beta-defensin (HBD) -2 and -3 were previously reported and used for correlations. Significantly higher levels of VitD were found in plasma as well as higher mRNA RU of VDR in PBMCs, and in genital mucosa from HESN compared to HCs. In addition, higher mRNA RU of TNF-α, IL-1β and IL-10, and lower mRNA RU of TGF-β were found in PBMC from HESNs compared to HCs. We also observed higher IL-10 mRNA RU in genital mucosa of HESNs compared to HCs, and the mRNA levels of TNF-α in oral and genital mucosa of SPs were higher compared to HESNs. Furthermore, positive correlations between VDR and IL-10 mRNA RU in PBMCs and genital mucosa of HESNs were found. Finally, HBD-2 and HBD-3 mRNA RU were positively correlated with VDR mRNA expression in oral mucosa from HESNs. These results suggest that high levels of VitD and its receptor are associated with natural resistance to HIV-1 infection. Up-regulation of the anti-inflammatory IL-10, and the induction of anti-HIV-1 defensins in mucosa might be part of the mechanisms involved in this association. However, further studies are required to define causal associations
    corecore