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1.
S Afr Med J ; 110(6): 505-513, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32880563

RESUMO

BACKGROUND: Lephalale Municipality in Limpopo Province, South Africa, has seen significant economic and industrial development owing to expansion of the coal mining and power generation sectors. This development has coincided with substantial population growth of 65% between 2001 and 2016, attributable to largely (migrant) males living in the area who, overall, outnumbered females by ~121:100. The local HIV prevalence is reported to be higher than national rates. OBJECTIVES: Anonymised National Health Laboratory Service CD4+ data were used to document increasing laboratory services workload and to establish the burden of advanced (CD4+ count <200 cells/µL) and very advanced (<100 cells/µL) HIV disease among adult patients accessing public healthcare in Lephalale between 2006 and 2015. METHODS: A cross-sectional design was used to analyse CD4+ laboratory data. CD4+ outcomes were categorised by volumes of tests, year, health facility type, age categories (15 - 19, 20 - 24, 25 - 29, 30 - 34, 35 - 39, 40 - 44, 45 - 49 and >49 years), CD4+ test range (≤50, 51 - 100, 101 - 200, 201 - 350, 351 - 500 and ≥501 cells/µL) and gender. Median CD4+ counts were calculated. RESULTS: Extracted Lephalale data comprised 57 490 CD4+ results, with a mean patient age of 34 years. Considerably fewer male than female patients had CD4+ counts reported (male/female ratio 0.45:1). CD4+ test volumes showed a five-fold escalation over the study period, increasing from 1 458 tests in 2006 to 8 239 in 2015. A considerable burden of advanced and very advanced HIV disease (exceeding 50% of all cases) was noted in 2006/2007; by 2015 the proportion had fallen, but was still high at 27%. The overall median CD4+ count in 2006 (192 cells/µL) confirmed a high burden of advanced disease, with modest improvement to 289 cells/µL by 2015. Between 2006 and 2015, the median CD4+ count for females increased from 204 to 405 cells/µL, while that for males increased from 126 to 285 cells/µL. Age analysis further revealed that men aged <20 years or >25 years, and specifically those aged 30 - 45 years, had up to 44% more advanced HIV disease. CONCLUSIONS: Lower median CD4+ counts and a dramatic increase in volumes of CD4+ tests performed from 2007 onwards revealed a high burden of advanced and very advanced HIV disease in patients accessing care in Lephalale. Viewed together with Statistics South Africa census documentation of a disproportionately high number of males compared with females living in the area, these figures suggest that improved systems are urgently needed to encourage and accommodate access to HIV care for male (migrant worker) patients living and working in emerging industrial centres.


Assuntos
Infecções por HIV/epidemiologia , Acessibilidade aos Serviços de Saúde , Adolescente , Adulto , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores Sexuais , África do Sul/epidemiologia , População Urbana
2.
S Afr Med J ; 111(1): 26-32, 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33404002

RESUMO

BACKGROUND: Prostate cancer (PCa) is the leading male neoplasm in South Africa (SA) and is the second most frequently diagnosed cancer among men globally. Age-specific incidence rates (ASIRs) vary by up to 189-fold globally, with an ASIR of 68.0 per 100 000 in 2018 in SA. OBJECTIVES: To describe PCa among men undergoing prostate biopsy in Gauteng Province, SA. METHODS: We undertook a retrospective descriptive study using prostate biopsy data collected from the National Health Laboratory Service (NHLS) database between 2006 and 2016. We extracted the Systematized Nomenclature of Medicine (SNOMED) clinical terms morphology and topography codes to assign histological findings using the International Classification of Diseases for Oncology. PCa was defined as adenocarcinoma with a reported Gleason Score (GS). The new grade group (GG) based on the GS is defined as follows; (i) GG1 for a GS ≤6; (ii) GG2 for a GS of 3 + 4 = 7 ; (iii) GG3 for a GS of 4 + 3 = 7; (iv) GG4 for a GS of 8; and (v) GG5 for a GS ≥9. Higher-grade disease was defined as GG4 and GG5 (GS ≥8), in line with local guidelines. We reported associations of PCa with a GS ≥7 with age and race and used provincial and world standard population data to determine annual ASIRs. RESULTS: We identified 22 937 biopsies referred to the NHLS between 2006 and 2016. Of the 6 448 biopsies (39%) with a PCa finding for black Africans, 46% were diagnosed with high-risk PCa compared with 36 - 40% for other race groups (p<0.0001). Black Africans were more likely than whites to have GG4 or GG5 PCa (odds ratio 1.45; 95% confidence interval 1.27 - 1.67). The ASIR increased from 44.9 per 100 000 in 2006 to 57.3 per 100 000 in 2016. CONCLUSIONS: Black African men were significantly more likely to present with PCa with a GS ≥8 (GG4 and GG5) compared with the other racial groups in Gauteng. The ASIR increased dramatically during the study period, perhaps as a result of increased screening and awareness. There is a need for additional research to better understand why black African men present with higher-grade disease.


Assuntos
Biópsia , Programas de Rastreamento/métodos , Neoplasias da Próstata/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Humanos , Incidência , Laboratórios , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Estudos Retrospectivos , África do Sul/epidemiologia
3.
Stud Health Technol Inform ; 264: 1437-1438, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438169

RESUMO

Prostate cancer (PCa) data is of public health importance in South Africa. Biopsy data is recorded as semi-structured narrative text that is not easily analysed. Our study reports a pilot study that applied predictive analytics and text mining techniques to extract prognostic information that guides patient management. In particular, the Gleason score (GS) reported in a number of formats were extracted successfully. Our study reports that predominantly older men were diagnosed with PCa reporting a high-risk GS (8-10). Where cell differentiation was reported, 64% of biopsies reported poor differentiation. The approaches demonstrated in our study should be extended to a larger dataset to assess whether it has the potential to scale up to the national level.


Assuntos
Big Data , Neoplasias da Próstata , Humanos , Masculino , Gradação de Tumores , Projetos Piloto , África do Sul
5.
S Afr Med J ; 106(4): 53-4, 2016 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-27032853

RESUMO

BACKGROUND: The National Health Laboratory Service (NHLS) performs ~4 million CD4 tests per annum for the public health sector at 61 CD4 testing laboratories across South Africa. Currently, CD4 laboratory data captured do not differentiate between antiretroviral treatment (ART) and pre-ART care. METHODS: A cross-sectional study was undertaken to evaluate a redesigned Comprehensive Care, Management and Treatment of HIV and AIDS (CCMT) request form, incorporating a two-tick collection procedure linking the CD4 test request to patient CCMT programme status. Field testing was undertaken at three health facilities, where healthcare personnel were required to capture whether the CD4 count requested was a 'first-ever CD4', 'CD4 taken previously, not yet in ART care' or 'in ART care'. All data were extracted from the NHLS Corporate Data Warehouse and analysed using Microsoft Excel and Stata-12. RESULTS: A substantial increase in the number of request forms with a CCMT programme status (28.1% v. 84.4%) was reported pre- and post-implementation. Post-implementation data (N=1 004) revealed that 30.8% patients were ART naive ('first-ever CD4'), with 7.4% 'not yet on ART' (median CD4 counts of 150 and 328 cells/µL, respectively). Patients on ART comprised 61.9% of the study group (median CD4 count ~346 cells/µL). Sixty percent of patients were aged between 30 and 44 years, and females predominated (male/female ratio 0.7:1). CONCLUSIONS: A simple modification to the CCMT request form can successfully facilitate collection of programme status. For national implementation, it would be advantageous to have a unique patient identifier to further enhance laboratory-based programmatic monitoring and evaluation.

7.
S Afr Med J ; 106(1): 82-7, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26792313

RESUMO

BACKGROUND: The CD4 integrated service delivery model (ITSDM) provides for reasonable access to pathology services across South Africa (SA) by offering three new service tiers that extend services into remote, under-serviced areas. ITSDM identified Pixley ka Seme as such an under-serviced district. OBJECTIVE: To address the poor service delivery in this area, a new ITSDM community (tier 3) laboratory was established in De Aar, SA. Laboratory performance and turnaround time (TAT) were monitored post implementation to assess the impact on local service delivery. METHODS: Using the National Health Laboratory Service Corporate Data Warehouse, CD4 data were extracted for the period April 2012-July 2013 (n=11,964). Total mean TAT (in hours) was calculated and pre-analytical and analytical components assessed. Ongoing testing volumes, as well as external quality assessment performance across ten trials, were used to indicate post-implementation success. Data were analysed using Stata 12. RESULTS: Prior to the implementation of CD4 testing at De Aar, the total mean TAT was 20.5 hours. This fell to 8.2 hours post implementation, predominantly as a result of a lower pre-analytical mean TAT reducing from a mean of 18.9 to 1.8 hours. The analytical testing TAT remained unchanged after implementation and monthly test volumes increased by up to 20%. External quality assessment indicated adequate performance. Although subjective, questionnaires sent to facilities reported improved service delivery. CONCLUSION: Establishing CD4 testing in a remote community laboratory substantially reduces overall TAT. Additional community CD4 laboratories should be established in under-serviced areas, especially where laboratory infrastructure is already in place.

8.
Adv Bioinformatics ; 2009: 235320, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20145719

RESUMO

We demonstrate the application and comparative interpretations of three tree-based algorithms for the analysis of data arising from flow cytometry: classification and regression trees (CARTs), random forests (RFs), and logic regression (LR). Specifically, we consider the question of what best predicts CD4 T-cell recovery in HIV-1 infected persons starting antiretroviral therapy with CD4 count between 200 and 350 cell/muL. A comparison to a more standard contingency table analysis is provided. While contingency table analysis and RFs provide information on the importance of each potential predictor variable, CART and LR offer additional insight into the combinations of variables that together are predictive of the outcome. In all cases considered, baseline CD3-DR-CD56+CD16+ emerges as an important predictor variable, while the tree-based approaches identify additional variables as potentially informative. Application of tree-based methods to our data suggests that a combination of baseline immune activation states, with emphasis on CD8 T-cell activation, may be a better predictor than any single T-cell/innate cell subset analyzed. Taken together, we show that tree-based methods can be successfully applied to flow cytometry data to better inform and discover associations that may not emerge in the context of a univariate analysis.

11.
J Immunol Methods ; 257(1-2): 145-54, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11687248

RESUMO

We tested the feasibility and precision of affordable CD4+ T cell counting in resource-poor settings using a recently standardised fixative, TransFix in whole blood (WB) by flow cytometry (FCM). The precision of the assays was established under optimal conditions for single-platform FCM such as the volumetric CytoronAbsolute and the bead-based FACSCan. Fresh WB samples from HIV-seropositive and seronegative patients were tested in Tanzania and South Africa, fixed and sent to the UK for reanalysis 7 days later. Correlation, bias and limits of agreements were analysed by linear regression and the Bland-Altman test. Absolute CD4+ T cell counts remained stable for at least 10 days when TransFix was added to WB in 1:10 dilution at 20-25 degrees C, and for 7 days when added in 1:10 or 1:5 dilution to samples stored to mimic 'tropical' conditions at 37 degrees C. Higher temperatures such as 42 degrees C were tolerated for only short periods since the recovery had decreased to 63% by day 3. The reproducibility of lymphocyte subset analysis remained unchanged by TransFix with coefficient of variations <6% for all T cell subsets. Absolute CD4+ T cell counts and CD4+ T cell % values on fixed samples in the UK showed a high correlation with the results using fresh samples in Tanzania (r=0.993 and 0.969, respectively) and with the samples handled in Johannesburg (r=0.991 and 0.981) with minimal bias. Primary CD4 gating using only a single CD4 antibody also remained accurate in TransFixed samples (r=0.999). Thus, TransFix permits optimal fixation and transport of WB samples in the developing world for FCM to local regional laboratories and for quality assurance in international centres. When used together with inexpensive primary CD4 gating, TransFix will allow reliable and affordable CD4+ T cell counting by FCM in resource-poor settings.


Assuntos
Contagem de Linfócito CD4/métodos , Citometria de Fluxo/métodos , Adulto , Contagem de Linfócito CD4/economia , Contagem de Linfócito CD4/estatística & dados numéricos , Países em Desenvolvimento , Fixadores , Citometria de Fluxo/economia , Citometria de Fluxo/estatística & dados numéricos , Soronegatividade para HIV/imunologia , Soropositividade para HIV/imunologia , Humanos , Laboratórios , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , África do Sul , Tanzânia
13.
SADJ ; 56(12): 602-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11887447

RESUMO

Cost effective solutions are needed for laboratory monitoring that do not compromise on quality but address costs. Current recommended methods of CD4+ T cell enumeration are complex and costly. Monitoring typically utilises viral load assessment (PCR based) and CD4+ T cell counting to assess disease progression and response to therapy in HIV/AIDS. This paper reviews CD4 testing with the focus on different methods of CD4+ T cell enumeration including state-of-the-art flow cytometric testing, the advantages and disadvantages of these systems and quality control. Lastly, recent new work undertaken at the University of the Witwatersrand is discussed that addresses the problems of cost and precision and accuracy of CD4 T cell testing.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Contagem de Linfócito CD4/métodos , Infecções por HIV/imunologia , Contagem de Linfócito CD4/economia , Contagem de Linfócito CD4/normas , Análise Custo-Benefício , Progressão da Doença , Citometria de Fluxo/economia , Citometria de Fluxo/métodos , Citometria de Fluxo/normas , Humanos , Laboratórios/economia , Laboratórios/normas , Antígenos Comuns de Leucócito/análise , Contagem de Leucócitos , Contagem de Linfócitos/métodos , Contagem de Linfócitos/normas , Controle de Qualidade , Carga Viral
14.
J Immunol Methods ; 222(1-2): 209-17, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10022387

RESUMO

The incidence of human immunodeficiency virus (HIV) infection continues to increase in South Africa. Limited resources are available for diagnosis and management of the disease and the development of affordable strategies is required. Absolute CD4 counts are used locally predominantly to monitor disease progression and institute prophylaxis against opportunistic infections. A dramatic increase in demand for CD4 counts prompted an investigation for a more cost-effective flow cytometry method than those currently recommended by the Centers for Disease Control (CDC). CD4 counts generated by two different single tube methods using CD3/CD4/CD8 [1(3)] and CD4 [1(1)] antibodies, respectively, were compared to the CDC recommended 6 tube 2 colour panel [6(2)]. Whole blood analysis using the Coulter Multi-Q-Prep system and an Epics XL Flow Cytometer (Coulter, Hialeah, FL) was performed for each of the three methods. Random samples from HIV positive adult patients were compared. A mean difference in the absolute CD4 counts of less than 10x10(6)/l was generated by both of the alternative panels when compared with the 6(2) panel. The precision of the three methods is comparable. In reagents alone, the 1(3) and 1(1) methods represent a cost saving of 76% and 93%, respectively, over the 6(2) method. The 1(3) and 1(1) panels would permit more affordable CD4 counts to be determined by the gold standard methodology of flow cytometry with no clinically significant sacrifices in accuracy or precision.


Assuntos
Contagem de Linfócito CD4/métodos , Infecções por HIV/imunologia , Adulto , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Citometria de Fluxo/métodos , Infecções por HIV/sangue , Humanos , Monitorização Imunológica , Subpopulações de Linfócitos T
15.
Cancer Lett ; 122(1-2): 17-23, 1998 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-9464486

RESUMO

Melatonin was previously shown to inhibit proliferation of MCF-7 human breast cancer cells. In this study the effect of melatonin on MCF-7 cells was further examined, while human cervical carcinoma (HeLa), osteosarcoma (MG-63) and lymphoblastoid (TK6) cells were tested for the first time. Haemocytometer counts, DNA content, flow cytometry and indirect immunofluorescence for nucleolar proteins, actin and beta-tubulin showed no differences in the growth, cell cycle or morphology between melatonin-exposed and control cells. The direct antiproliferative effect of melatonin thus seems to be confined to a melatonin-responsive subclone of MCF-7 cells and not applicable to the majority of cancer cells.


Assuntos
Antineoplásicos/farmacologia , Melatonina/farmacologia , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , DNA de Neoplasias/análise , Relação Dose-Resposta a Droga , Feminino , Citometria de Fluxo , Células HeLa , Humanos , Osteossarcoma/patologia , Células Tumorais Cultivadas
16.
Pediatr Hematol Oncol ; 14(1): 43-50, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9021812

RESUMO

The use of flow cytometry in the diagnosis of Bernard-Soulier syndrome (BSS) in patients with giant platelets and thrombocytopenia was investigated as an adjunct to ristocetin-induced platelet aggregation (RIPA) studies because of problems experienced with aggregation studies, particularly at the time of presentation, in the pediatric age group. Eight patients suspected of having BSS were studied with respect to platelet expression of glycoprotein Ib alpha (CD42b) and glycoprotein IIIa (CD61) using an EPICS Profile II flow cytometer. Twelve patients with normal platelet morphology and platelet counts were used as normal controls. One patient with Alport's syndrome, four patients with immune thrombocytopenic purpura (ITP), and one patient with Glanzmann thrombasthenia were also studied. In all eight patients suspected of having BSS, deficiency of glycoprotein Ib alpha was demonstrated. Normal expression was demonstrated in 12 control patients, in one patient with giant platelets with Alport's syndrome, and in four patients with ITP. Absence of glycoprotein IIIa was demonstrated in Glanzmann thrombasthenia. In the pediatric age group one is able to demonstrate abnormalities of platelet membrane glycoprotien in patients with thrombocytopathias using flow cytometry. This method has the advantage of being rapid and can be performed on small volumes of blood suitable for pediatric practice.


Assuntos
Síndrome de Bernard-Soulier/diagnóstico , Citometria de Fluxo , Glicoproteínas da Membrana de Plaquetas/análise , Síndrome de Bernard-Soulier/sangue , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
17.
Leuk Res ; 16(12): 1197-201, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1465029

RESUMO

During the 25 month period from July 1989 until August 1991, 58 children with FAB defined acute lymphoblastic leukaemia (ALL) were referred for immunophenotypic analysis. Of these, 42 children with a common/pre-B phenotype (CD19/CD10-positive) were studied specifically to assess CD10 antigen density. A pattern of segregation was found between males and females and between black and white children. Black males, who are the worst prognostic group, had the lowest CD10 density, while white females, known to constitute the best prognostic group, had significantly higher CD10 antigen density than the other groups. Black females and white males occupied intermediate positions with respect to CD10 antigen density. A two way analysis of variance showed that although sex had contributed significantly to this variation (p = 0.0038), the contribution of race was marginal (p = 0.0530). It is hypothesized that low CD10 antigen density patterns in males and in Blacks could be causally related to poor prognosis.


Assuntos
População Negra , Neprilisina/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , População Branca , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fatores Sexuais
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