Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
1.
OMICS ; 26(1): 35-50, 2022 01.
Article in English | MEDLINE | ID: mdl-34958284

ABSTRACT

Pharmacogenomics is universally relevant for worldwide modern therapeutics and yet needs further development in resource-limited countries. While there is an abundance of genetic association studies in controlled medical settings, there is a paucity of studies with a naturalistic design in real-life clinical practice in patients with comorbidities and under multiple drug treatment regimens. African patients are often burdened with communicable and noncommunicable comorbidities, yet the application of pharmacogenomics in African clinical settings remains limited. Using warfarin as a model, this study aims at minimizing gaps in precision/personalized medicine research in African clinical practice. We present, therefore, pharmacogenomic profiles of a cohort of 503 black Africans (n = 252) and Mixed Ancestry (n = 251) patients from Southern Africa, on warfarin and co-prescribed drugs in a naturalized noncontrolled environment. Seventy-three (n = 73) single nucleotide polymorphisms (SNPs) in 29 pharmacogenes were characterized using a combination of allelic discrimination, Sanger sequencing, restriction fragment length polymorphism, and Sequenom Mass Array. The common comorbidities were hypertension (43-46%), heart failure (39-45%), diabetes mellitus (18%), arrhythmia (25%), and HIV infection (15%). Accordingly, the most common co-prescribed drugs were antihypertensives, antiarrhythmic drugs, antidiabetics, and antiretroviral therapy. We observed marked variation in major pharmacogenes both at interethnic levels and within African subpopulations. The Mixed Ancestry group presented a profile of genetic variants reflecting their European, Asian, and African admixture. Precision medicine requires that African populations begin to capture their own pharmacogenetic SNPs as they cannot always infer with absolute certainty from Asian and European populations. In the current historical moment of the COVID-19 pandemic, we also underscore that the spectrum of drugs interacting with warfarin will likely increase, given the systemic and cardiovascular effects of COVID-19, and the anticipated influx of COVID-19 medicines in the near future. This observational clinical pharmacogenomics study of warfarin, together with past precision medicine research, collectively, lends strong support for incorporation of pharmacogenetic profiling in clinical settings in African patients for effective and safe administration of therapeutics.


Subject(s)
COVID-19 , HIV Infections , Anticoagulants/therapeutic use , Humans , Pandemics , Pharmacogenetics , Polymorphism, Single Nucleotide/genetics , Precision Medicine , SARS-CoV-2 , Warfarin/therapeutic use
2.
Lancet ; 387(10024): 1187-97, 2016 Mar 19.
Article in English | MEDLINE | ID: mdl-26970721

ABSTRACT

BACKGROUND: HIV-associated tuberculosis is difficult to diagnose and results in high mortality. Frequent extra-pulmonary presentation, inability to obtain sputum, and paucibacillary samples limits the usefulness of nucleic-acid amplification tests and smear microscopy. We therefore assessed a urine-based, lateral flow, point-of-care, lipoarabinomannan assay (LAM) and the effect of a LAM-guided anti-tuberculosis treatment initiation strategy on mortality. METHODS: We did a pragmatic, randomised, parallel-group, multicentre trial in ten hospitals in Africa--four in South Africa, two in Tanzania, two in Zambia, and two in Zimbabwe. Eligible patients were HIV-positive adults aged at least 18 years with at least one of the following symptoms of tuberculosis (fever, cough, night sweats, or self-reported weightloss) and illness severity necessitating admission to hospital. Exclusion criteria included receipt of any anti-tuberculosis medicine in the 60 days before enrolment. We randomly assigned patients (1:1) to either LAM plus routine diagnostic tests for tuberculosis (smear microscopy, Xpert-MTB/RIF, and culture; LAM group) or routine diagnostic tests alone (no LAM group) using computer-generated allocation lists in blocks of ten. All patients were asked to provide a urine sample of at least 30 mL at enrolment, and trained research nurses did the LAM test in patients allocated to this group using the Alere Determine tuberculosis LAM Ag lateral flow strip test (Alere, USA) at the bedside on enrolment. On the basis of a positive test result, the nurses made a recommendation for initiating anti-tuberculosis treatment. The attending physician made an independent decision about whether to start treatment or not. Neither patients nor health-care workers were masked to group allocation and test results. The primary endpoint was 8-week all-cause mortality assessed in the modified intention-to-treat population (those who received their allocated intervention). This trial is registered with ClinicalTrials.gov, number NCT01770730. FINDINGS: Between Jan 1, 2013, and Oct 2, 2014, we screened 8728 patients and randomly assigned 2659 to treatment (1336 to LAM, 1323 to no LAM). 108 patients did not receive their allocated treatment, mainly because they did not meet the inclusion criteria, and 23 were excluded from analysis, leaving 2528 in the final modified intention-to-treat analysis (1257 in the LAM group, 1271 in the no LAM group). Overall all-cause 8-week mortality occurred in 578 (23%) patients, 261 (21%) in LAM and 317 (25%) in no LAM, an absolute reduction of 4% (95% CI 1-7). The risk ratio adjusted for country was 0·83 (95% CI 0·73-0·96), p=0·012, with a relative risk reduction of 17% (95% CI 4-28). With the time-to-event analysis, there were 159 deaths per 100 person-years in LAM and 196 per 100 person-years in no LAM (hazard ratio adjusted for country 0·82 [95% CI 0·70-0·96], p=0·015). No adverse events were associated with LAM testing. INTERPRETATION: Bedside LAM-guided initiation of anti-tuberculosis treatment in HIV-positive hospital inpatients with suspected tuberculosis was associated with reduced 8-week mortality. The implementation of LAM testing is likely to offer the greatest benefit in hospitals where diagnostic resources are most scarce and where patients present with severe illness, advanced immunosuppression, and an inability to self-expectorate sputum. FUNDING: European Developing Clinical Trials Partnership, the South African Medical Research Council, and the South African National Research Foundation.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , Lipopolysaccharides/urine , Point-of-Care Systems , Tuberculosis/diagnosis , AIDS-Related Opportunistic Infections/drug therapy , AIDS-Related Opportunistic Infections/immunology , AIDS-Related Opportunistic Infections/mortality , Adult , Africa/epidemiology , Antitubercular Agents/therapeutic use , Biomarkers/urine , CD4 Lymphocyte Count , Diagnostic Tests, Routine , Female , Hospitalization , Humans , Length of Stay/statistics & numerical data , Male , Sensitivity and Specificity , Treatment Outcome , Tuberculosis/drug therapy , Tuberculosis/immunology , Tuberculosis/mortality
4.
BMC Infect Dis ; 16: 20, 2016 Jan 22.
Article in English | MEDLINE | ID: mdl-26797499

ABSTRACT

BACKGROUND: In Zimbabwe, sputum smear microscopy (SSM) is the routinely used TB diagnostic tool in hospitalised HIV-infected patients. However, SSM has poor sensitivity in HIV-infected patients. We compared performance of urine lipoarabinomannan strip test (LAM) and SSM among hospitalized HIV-infected patients with suspected TB. METHODS: Hospitalized HIV-infected patients with suspected TB were randomized to LAM plus SSM or SSM alone groups as part of a larger multi-country parent study. Here we present a comparison of LAM versus SSM performance from the Zimbabwe study site. LAM analyses (grade 2 cut-off) were conducted using (i) a microbiological reference standard (MRS; culture positivity for M.tb and designated definite TB) and (ii) a composite reference standard (CRS; definite TB plus probable TB i.e. patients with clinical TB excluded from the culture negative group). CRS constituted the primary analysis. RESULTS: 82/457 (18%) of the patients randomized to the LAM group were M.tuberculosis culture positive. Using CRS, sensitivity (%, 95% CI) of LAM was significantly higher than SSM [49.2 (42.1-56.4) versus 29.4(23.2-36.3); p < 0.001]. Specificity and PPV were 98.1%, and 95.8%, respectively. By contrast, using MRS, LAM sensitivity was similar to SSM and specificity was significantly lower, however, the combined sensitivity of LAM and SSM was significantly higher than that of SSM alone, p = 0.009. Using CRS, LAM sensitivity (%, CI) was CD4 count dependent [60.6(50.7-69.8) at ≤50 cells/µL; 40.0(22.7-59.4) at 51-100 cells/µL, and 32.8(21.0-46.3) at >100 cells/µL. The combined sensitivity of LAM and SSM was higher than SSM alone being highest at CD4 counts <50 cells/µL [67.6(57.9-76.3); p = <0.001]. Specificity of LAM or SSM alone, or of combined LAM and SSM was >97% in all the 3 CD4 strata. CONCLUSION: Among hospitalized HIV-infected patients with suspected TB, the sensitivity of LAM is significantly higher than that of SSM, especially at low CD4 counts. LAM and SSM are complimentary tests for diagnosis of TB in HIV-infected patients. We recommend a combination of LAM and SSM for TB diagnosis in HIV-infected patients with low CD4 counts in HIV/TB co-endemic countries, where alternative methods are unavailable.


Subject(s)
HIV Infections/complications , Lipopolysaccharides/urine , Mycobacterium tuberculosis/isolation & purification , Sputum/microbiology , Tuberculosis/diagnosis , Adult , Female , Humans , Male , Microscopy , Middle Aged , Mycobacterium tuberculosis/physiology , Sensitivity and Specificity , Tuberculosis/etiology , Tuberculosis/microbiology , Zimbabwe/epidemiology
5.
AIDS Care ; 24(3): 358-68, 2012.
Article in English | MEDLINE | ID: mdl-21902570

ABSTRACT

Disclosure of positive HIV status in Sub-Saharan Africa has been associated with safer sexual practices and better antiretroviral therapy (ART) adherence, but associations with psychosocial function are unclear. We examined patterns and psychosocial correlates of disclosure in a Zimbabwean community. Two hundred HIV positive women at different stages of initiating ART participated in a cross-sectional study examining actual disclosures, disclosure beliefs, perceived stigma, self-esteem, depression, and quality of life. Ninety-seven percent of the women disclosed to at least one person, 78% disclosed to their current husband/partner, with an average disclosure of four persons per woman. The majority (85-98%) of disclosures occurred in a positive manner and 72-95% of the individuals reacted positively. Factors significantly correlated with HIV disclosure to partners included being married, later age at menses, longer duration of HIV since diagnosis, being on ART, being more symptomatic at baseline, ever having used condoms, and greater number of partners in the last year. In multivariate analysis, being married and age at menses predicted disclosure to partners. Positive disclosure beliefs, but not the total number of disclosures, significantly correlated with lower perceived stigma (ρ = 0.44 for personalized subscale and ρ = 0.51 for public subscale, both p<0.0001), higher self-esteem (ρ = 0.15, p=0.04), and fewer depressive symptoms (ρ = -0.14, p=0.05). In conclusion, disclosure of positive HIV status among Zimbabwean women is common and is frequently met with positive reactions. Moreover, positive disclosure beliefs correlate significantly with psychosocial measures, including lower perceived stigma, higher self-esteem, and lower depression.


Subject(s)
HIV Infections/psychology , HIV Seropositivity/psychology , Self Disclosure , Adult , Africa South of the Sahara , Aged , Anti-Retroviral Agents/therapeutic use , Cross-Sectional Studies , Depression , Female , HIV Infections/prevention & control , Humans , Medication Adherence , Middle Aged , Psychology , Self Concept , Sexual Partners/psychology , Social Stigma , Young Adult , Zimbabwe
6.
PLoS One ; 6(6): e21241, 2011.
Article in English | MEDLINE | ID: mdl-21698125

ABSTRACT

The rapid scale-up of highly active antiretroviral therapy (HAART) and use of single dose Nevirapine (SD NVP) for prevention of mother-to-child transmission (pMTCT) have raised fears about the emergence of resistance to the first line antiretroviral drug regimens. A cross-sectional study was conducted to determine the prevalence of primary drug resistance (PDR) in a cohort of young (<25 yrs) HAART-naïve HIV pregnant women attending antenatal clinics in Chitungwiza, Zimbabwe. Whole blood was collected in EDTA for CD4 counts, viral load, serological estimation of duration of infection using the BED Calypte assay and genotyping for drug resistance. Four hundred and seventy-one women, mean age 21 years; SD: 2.1 were enrolled into the study between 2006 and 2007. Their median CD4 count was 371cells/µL; IQR: 255-511 cells/µL. Two hundred and thirty-six samples were genotyped for drug resistance. Based on the BED assay, 27% were recently infected (RI) whilst 73% had long-term infection (LTI). Median CD4 count was higher (p<0.05) in RI than in women with LTI. Only 2 women had drug resistance mutations; protease I85V and reverse transcriptase Y181C. Prevalence of PDR in Chitungwiza, 4 years after commencement of the national ART program remained below WHO threshold limit (5%). Frequency of recent infection BED testing is consistent with high HIV acquisition during pregnancy. With the scale-up of long-term ART programs, maintenance of proper prescribing practices, continuous monitoring of patients and reinforcement of adherence may prevent the acquisition and transmission of PDR.


Subject(s)
Drug Resistance, Viral , HIV Infections/drug therapy , Population Surveillance , Adult , CD4 Lymphocyte Count , Female , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/isolation & purification , Humans , Viral Load , Zimbabwe/epidemiology
7.
Afr J Reprod Health ; 14(2): 27-35, 2010 Jun.
Article in English | MEDLINE | ID: mdl-21243916

ABSTRACT

As access to anti-retroviral therapy (ART) increases in sub-Saharan Africa, fertility and contraception patterns are likely to change. Two hundred HIV-positive women at an ART roll-out site in Zimbabwe responded to a questionnaire on fertility desires and condom use. Ten women (5%) reported planning a pregnancy in the next year, comprising 0% of women not yet eligible for ART, 8.22% of women on the waitlist for ART, and 4.17% of women on ART. Younger age, fewer living children, and higher quality of life were individually associated with intended pregnancy in the next year; however in multivariate analysis only the association with higher quality of life remained significant. Reported ever use of condoms was relatively low (46.5%) and condom use varied by neither ART status nor by fertility desires. In conclusion, our data demonstrates fertility desires among HIV-positive women in Zimbabwe correlate with higher perceived quality of life.


Subject(s)
Condoms/statistics & numerical data , Fertility , HIV Infections/psychology , Intention , Analysis of Variance , Antiretroviral Therapy, Highly Active , Contraception Behavior , Cross-Sectional Studies , Female , HIV Infections/drug therapy , HIV Infections/epidemiology , Health Services Accessibility , Humans , Pregnancy , Quality of Life , Statistics, Nonparametric , Surveys and Questionnaires , Young Adult , Zimbabwe
8.
Article in English | AIM (Africa) | ID: biblio-1258453

ABSTRACT

As access to anti-retroviral therapy (ART) increases in sub-Saharan Africa, fertility and contraception patterns are likely to change. Two hundred HIV-positive women at an ART roll-out site in Zimbabwe responded to a questionnaire on fertility desires and condom use. Ten women (5%) reported planning a pregnancy in the next year, comprising 0% of women not yet eligible for ART, 8.22% of women on the waitlist for ART, and 4.17% of women on ART. Younger age, fewer living children, and higher quality of life were individually associated with intended pregnancy in the next year; however in multivariate analysis only the association with higher quality of life remained significant. Reported ever use of condoms was relatively low (46.5%) and condom use varied by neither ART status nor by fertility desires. In conclusion, our data demonstrates fertility desires among HIV-positive women in Zimbabwe correlate with higher perceived quality of life (Afr. J. Reprod. Health 2010; 14[2]: 27-35)


Subject(s)
Antiretroviral Therapy, Highly Active , Condoms/statistics & numerical data , Fertility , HIV Seropositivity , Quality of Life , Women , Zimbabwe
9.
AIDS Care ; 21(12): 1517-27, 2009 Dec.
Article in English | MEDLINE | ID: mdl-20024731

ABSTRACT

Little is known about the psychosocial impact of antiretroviral therapy (ART) among women in sub-Saharan Africa. Therefore, we conducted a cross-sectional study in Zimbabwe to assess the impact of ART on HIV-positive women's health-related quality of life, using the Medical Outcomes Study-HIV Quality of Life (QOL) questionnaire. Additionally, we assessed socio-demographics, reproductive and sexual health, HIV-related history, disclosure, social stigma, self-esteem, and depression. Structured interviews were conducted with 200 HIV-positive women and categorized into three groups by treatment: (1) Group 1 (n=31) did not meet clinical or laboratory criteria to begin treatment; (2) Group 2 (n=73) was eligible to begin treatment but awaiting initiation of treatment; and (3) Group 3 (n=96) was on ART for a median of 13 months. The women had similar socio-demographic characteristics but varied significantly in clinical characteristics. Women on ART reported fewer AIDS-related symptoms in the last week and year and had higher current and lower baseline CD4 counts compared to women not on ART. On most QOL domains women on ART reported higher mean scores as compared to women not on ART (p<0.01). Additionally, women on ART reported less depression compared to women not on ART (p<0.001). Between the two groups of women not on ART, unexpectedly, there were no significant differences in their scores for QOL or depression. Thus, Zimbabwean women living with HIV experience better overall QOL and lower depression on ART. Altogether, our findings suggest that ART delivery in resource-poor communities can enhance overall QOL as well as psychosocial functioning, which has wide-ranging public health implications.


Subject(s)
Anti-HIV Agents/therapeutic use , HIV Infections/drug therapy , Quality of Life , Adolescent , Adult , Aged , CD4 Lymphocyte Count , Depressive Disorder/etiology , Disclosure , Female , Humans , Middle Aged , Self Concept , Stereotyping , Young Adult , Zimbabwe
10.
J Transl Med ; 4: 33, 2006 Aug 14.
Article in English | MEDLINE | ID: mdl-16907973

ABSTRACT

BACKGROUND: The World Health Organization (WHO)'s "3 x 5 program" has spurred efforts to place 3 million people on combination antiretroviral therapy (ART) for treatment of AIDS in resource-limited countries. Paradoxically, the cost of CD4+ T-lymphocyte count essential for decision-making to commence HIV positive adults on ART as well as for monitoring responses to ART remains unaffordable in most resource-limited countries. Thus, low-cost methods for enumerating CD4+ T-lymphocyte are urgently needed. OBJECTIVE: To evaluate Cyflow cytometry (Cyflow SL, Partec, Munster, Germany) for enumeration of absolute CD4+ T-lymphocyte in subtype C HIV-1 seropositive subjects using FACSCount (Becton and Dickinson, Immunocytometry Systems, San Jose, CA, USA) as the "predicate method". METHODS: A total of 150 HIV-1 seropositive subjects were included in the evaluation exercise. Fifty-eight specimens were collected from pregnant HIV-1 seropositive women (subtype C drug resistance study). Twenty-seven specimens were collected from women and their spouses with AIDS followed in a Duke ART study to assess the immunologic and virologic responses to generic ART, comprising Stavudine, Lamivudine and Nevirapine (Stalanev, Varichem Labs, Harare, Zimbabwe). Sixty-five specimens were collected from AIDS patients enrolled in an ongoing Kaposi Sarcoma (KS) study to investigate impact of ART on KS progression. Enumeration of CD4+ T-lymphocytes using FACSCount is routinely conducted for all the three studies. The Medical Research Council of Zimbabwe and Medicines Control Authority of Zimbabwe approved the studies. Whole blood was collected in EDTA vacutainer tubes and aliquoted into two tubes (200 microL in each). CD4+ T-lymphocyte counts were enumerated using a Cyflow counter, in the Department of Immunology and a FACSCount in the Department of Obstetrics and Gynaecology within 6 hours of phlebotomy following manufacturers' instructions. RESULTS: Using linear regression analysis, there was a very strong correlation (R = 0.991) between the overall CD4+ T-lymphocyte counts obtained by FACSCount and those obtained by Cyflow. When data analysis was stratified by study groups, there was a strong correlation between the FACSCount and Cyflow CD4+ T-lymphocyte counts from subjects in the three independent studies; Subtype C resistance (R2 = 0.987), Duke ART (R2 = 0.980) and KS (R2 = 0.994), Table 1. Using Bland-Altman plots, the overall, absolute CD4+ T lymphocytes obtained by the two methods were in excellent agreement (mean difference 1.21, 95% Confidence Interval {CI): -2.1 to 3.3). For the 0-250 CD4+ T-lymphocytes range, the CD4 counts obtained using FACSCount were also in good agreement with those obtained using Cyflow counter (mean difference = 2.6 cells/microL, 95% CI: -1.1 to 6.3). Similarly, in the 251-500 (mean difference 1.0, cells/microL, 95% CI: -3.7 to 5.6) and the 501-1200 (mean difference = 0.29 cells/microL, 95% CI: -8.1 to 8.7) CD4 T-lymphocytes range, good agreement was observed. CONCLUSION: The Cyflow counter is as accurate as the FACSCount in enumerating absolute CD4+ T-lymphocytes in the range 1-1200 cells/muL. Cyflow cytometry is relatively affordable, easy to use technology that is useful not only in identifying HIV seropositive individuals who require ART but also for monitoring immunologic responses to ART.

11.
Pediatr Infect Dis J ; 21(1): 54-6, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11791100

ABSTRACT

BACKGROUND: The number of children with AIDS in Africa is high. Such children may be at risk for cryptococcal meningoencephalitis, but data are scarce regarding this disease in our population. METHODS: We examined records of HIV-infected children (< or =16 years) diagnosed with cryptococcal meningoencephalitis in Harare, Zimbabwe, between 1995 and 2000. To elucidate features unique to pediatric disease, the children were compared with adult patients with HIV-associated cryptococcal meningoencephalitis. RESULTS: Thirteen children presented to our institution with headache (85%), nuchal rigidity (69%), vomiting (46%), impaired mental status (38%), convulsions (38%) and focal neurologic signs (23%). The mean duration of symptoms before diagnosis was 9 days. Cerebrospinal fluid examination revealed normal white blood cell counts in 64%, protein value in 67% and glucose concentration in 57% of patients. Children were more likely than adults to have seizures (38% vs. 11%, P = 0.02) and normal cerebrospinal fluid protein (67% vs. 10%, P < 0.01). The in-hospital mortality was 43%. Convulsions (P = 0.05) and impaired mental status (P < 0.01) were associated with increased mortality CONCLUSIONS: Cryptococcal meningoencephalitis in African children presents acutely or subacutely, can have a fulminant picture and is consistent with progressive meningoencephalitis.


Subject(s)
Acquired Immunodeficiency Syndrome/complications , Cryptococcus neoformans/pathogenicity , Immunocompromised Host , Meningitis, Cryptococcal/pathology , Seizures/etiology , Child , Child, Preschool , Cognition Disorders/etiology , Diagnosis, Differential , Disease Progression , Female , Headache/etiology , Humans , Infant , Male , Meningitis, Cryptococcal/mortality , Meningitis, Cryptococcal/virology , Neurologic Examination , Prognosis , Retrospective Studies , Risk Factors , Vomiting/etiology , Zimbabwe/epidemiology
SELECTION OF CITATIONS
SEARCH DETAIL