Article: Issues around HIV-1 diagnosis.O AnzalaEast African medical journal 09/2009; 86(9):409-10.
Article: Pregnancy rates among female participants in phase I and phase IIA AIDS vaccine clinical trials in Kenya.W G Jaoko, H Ogutu, S Wakasiaka, R Malogo, R Ndambuki, J Nyange, G Omosa-Manyonyi, P Fast, C Schmidt, C Verlinde, C Smith, K M Bhatt, J Ndinya-Achola, O Anzala[show abstract] [hide abstract]
ABSTRACT: Female participants in AIDS candidate vaccine clinical trials must agree to use effective contraception to be enrolled into the studies, and for a specified period after vaccination, since the candidate vaccines' effects on the embryo or foetus are unknown. To review data on female participants' pregnancy rates from phase I and IIA AIDS vaccine clinical trials conducted at the Kenya AIDS Vaccine Initiative (KAVI) and to discuss the challenges of contraception among female participants. Descriptive observational retrospective study. KAVI clinical trial site, Kenyatta National Hospital and University of Nairobi, Kenya. Thirty nine female participants were enrolled into these trials. They received family planning counselling and were offered a choice of different contraceptive methods, as per the protocols. All contraception methods chosen by the participants were offered at the study site at no cost to the participant. Four women conceived during the study period when pregnancies were to be avoided. All four had opted for sexual abstinence as a contraceptive method, but reported having been coerced by their partners to have unprotected sexual intercourse. Abstinence is clearly not a reliable contraceptive option for women in developing-country settings. Effective female-controlled contraceptives, administered at the clinical trial site, may empower female participants to better control their fertility, leading to more complete clinical trial data.East African medical journal 09/2009; 86(9):430-4.
Article: Serologic testing algorithm for recent HIV seroconversion in estimating incidence of HIV-1 among adults visiting a VCT centre at a Kenyan tertiary health institution.[show abstract] [hide abstract]
ABSTRACT: To determine HIV high risk groups among adults visiting Kenyatta National Hospital Voluntary Counselling and Testing Centre by use of Serologic Testing Algorithm for Recent HIV Seroconversion (STARHS). A cross-sectional study of adults. Kenyatta National Hospital Voluntary and Counselling Centre. Of the 6,415 adults screened for antibodies to HIV at Kenyatta National Hospital VCT Centre between July 2002 and February 2003, 728 tested positive in the two HIV screening tests used at the center, indicating a prevalence of 11%. Of these seropositive cases, 355 consented to participate in the study. Using STARHS, 34 (9.6%) of the plasma samples were classified as being from individuals with recent infection (within 170 days), giving an annual estimated HIV-1 incidence in this population of 1.3 infections per 100 person-years with a 95% CI of 0.872-1.728%. Young adults had a higher rate of new infection than older adults. Young females were infected much earlier in life, with a peak age of new infections of 26 years, versus 31 years for young males. This study confirms our hypothesis that STARHS or Detuned assay can be used to determine HIV incidence in this population. The HIV high risk groups as identified by this study are young women between ages 16 to 26 years old and men between ages 45 to 55 years of age.East African medical journal 05/2009; 86(5):212-8.
Article: Sensitivity and specificity of HIV rapid tests used for research and voluntary counselling and testing.[show abstract] [hide abstract]
ABSTRACT: HIV rapid tests (RT) are a quick and non-technically demanding means to perform HIV voluntary counselling and testing (VCT) but understanding their limitations is vital to delivering quality VCT. To determine the sensitivity and specificity of HIV rapid tests used for research and voluntary counselling and testing at four sites in East Africa. Cross-sectional study. Masaka District, Uganda; a sugar plantation in Kakira, Uganda; Coastal Villages in the Kilifi District of Kenya; and the Urban slum of Kangemi located West of Nairobi, Kenya. Six thousands two hundred and fifty five consenting volunteers were enrolled into the study, and 675 prevalent HIV infections were identified. The RT sensitivity tended to be high for all assays at all sites (97.63-100%) with the exception of the Uni-Gold assay (90.24% in Kangemi, 96.58% in Kilifi). Twenty four RT results were recorded as 'weak positives', 22 (92%) of which were negative by ELISA. There was a high rate of RT false positives in Uganda (positive predictive values ranging from 45.70% to 86.62%). The sensitivity and specificity of the RT varied significantly across sites. The rate of RT misclassification in Uganda suggests that a multiple test algorithm may be preferable to a single test as screener for HIV VCT.East African medical journal 11/2008; 85(10):500-4.
Article: Total lymphocyte count as a surrogate marker for CD4+ t cell count in initiating antiretroviral therapy at Kenyatta National Hospital, Nairobi.[show abstract] [hide abstract]
ABSTRACT: To evaluate the utility of Total Lymphocyte Count (TLC) as a surrogate marker for CD4 + T cell count in antiretroviral (ARV) treatment initiation in a Kenyan population of HIV seropositive patients at Kenyatta National Hospital. Cross-sectional descriptive study. Kenyatta National Hospital, HIV treatment and follow-up outpatient facility; Comprehensive Care Centre, Nairobi, Kenya. Two hundred and twenty five HIV Elisa positive, ARV naive patients visiting the Comprehensive Care Centre between January 2006 to March 2006. A significant linear correlation was found between TLC and CD4 cell count for the whole group with a Spearman rank correlation of 0.761 (p < 0.01); and was also independently observed in the four WHO clinical stages. The classification utility of TLC 1200 cells/mm3 cut-off was suboptimal; sensitivity 37% specificity of 99% and the NPV of 56%. The receiver operator characteristics (ROC) curve generated an optimal TLC cut-off of 1900 cells/mm3 cut-off to be of greatest utility with a sensitivity of 81.1%, specificity of 90.3%, PPV of 90.8% and NPV of 80.2%. This implies that a TLC cut-off of 1900 cells/mm3 correctly classify eight out of ten HIV positive patients as having a CD4 < 200 cells/mm3 and only misclassify two such patients. Serial CD4 testing can then be performed on the minority of patients who despite a TLC > or = 1900 cells/mm3 are, on basis of clinical data, suspect of more advanced disease warranting ARV therapy. This would reduce the number of patients tested for and focus the application of CD4 testing and thus reduce attendant cost in care provision in CD4 resource poor settings. Our data showed a good positive correlation between TLC and CD4 cell count, however the WHO recommended TLC cuto-ff of 1200/mm3 was found to be of low sensitivity in classifying patients as having a CD4 counts < 200 cells/mm3. This would result in underestimation of advanced stage of disease and to withholding ARVs treatment to persons who need treatment. We recommend a TLC cut-off of 1900 cells/mm3 for our population to classify patients as either above or below the CD4 count cut-off of 200 cells/mm3 as an indicator of when to start antiretroviral therapy.East African medical journal 11/2007; 84(10):466-72.