Impact of the international program for quality assessment and standardization for immunological measures relevant to HIV/AIDS: QASI

Mandy, Francis; Bergeron, Marcelle; Houle, Guy; Bradley, John; Fahey, John L.

doi:10.1002/cyto.10088

Cited by 45 publications

(56 citation statements)

References 18 publications

(25 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, implementation of uniform quality control procedures for routine clinical assays will be important (3,24) to ensure the inter-and intralaboratory comparabilities of baseline and longitudinal CD4 ϩ LC measurements.…”

Section: Discussionmentioning

confidence: 99%

Low CD4 ⁺ T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

Bussmann

Wester

Masupu

et al. 2004

Clin Vaccine Immunol

View full text Add to dashboard Cite

CD4+-lymphocyte counts (LCs) play a crucial role in the management and monitoring of HIV infection. Variability in CD4+ LCs has been reported to occur as a result of measurement techniques and/or biological variations. We report on the CD4+ LCs of healthy human immunodeficiency virus (HIV)-seronegative adults in Botswana. Samples were obtained from HIV-seronegative blood donors. The median CD4+ LC was 726 cells/mm3 (for females, 782 cells/mm3; for males, 698 cells/mm3). The median CD8+ LC was 488 cells/mm3 (for females, 494 cells/mm3; for males, 485 cells/mm3). The median CD4+-to-CD8+ ratio was 1.57 (for females, 1.66; for males, 1.51). Our findings of low CD4+ LCs among HIV-negative adults in Botswana are significant and have important implications for the management of HIV disease in the population of this sub-Saharan African country

show abstract

Section: Discussionmentioning

confidence: 99%

Low CD4 ⁺ T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

Bussmann

Wester

Masupu

et al. 2004

Clin Vaccine Immunol

View full text Add to dashboard Cite

show abstract

“…they do not provide the %CD4þ cell counts in the lymphocyte population. All laboratories performing CD4 testing should enroll in an external proficiency program (27,28). The reality however is that for many laboratories in resource limited countries, participation in international quality assurance programs (such as the UKNE-QUAS and QAS) for monitoring the performance of these low-cost cytometers remains a challenge (17).…”

Section: Cd41 T Lymphocytes Enumerationmentioning

confidence: 99%

CD4 T cell measurements in the management of antiretroviral therapy-A review with an emphasis on pediatric HIV-infected patients

O’Gorman

Zijenah

2008

Cytometry

View full text Add to dashboard Cite

The measurement of both the percentage (in pediatric patients aged less than 5 or 6 years) and the absolute number of circulating CD41 T cells remains the single most important parameter for establishing prognosis and determining when to treat HIV-1 infected infants. The predictive power of CD41 T cell measurements in HIV-1 infected individuals has resulted in robust guidelines from numerous agencies on the use of CD41 T cell measurements ranging from pretreatment evaluations to the initial assessment and monitoring of therapeutic responses and treatment failures. The increase in availability of HIV-1 antiretroviral drugs in resource limited setting has led to the urgent need to develop systems and technologies for the accurate and cost-effective measurement of CD41 T cells. The establishment of standardized guidelines for antiretroviral therapy (including CD4 testing) along with significant advancements in the development of structured access to health care, centralized CD4 testing programs, improved quality assurance programs, and inexpensive CD4 measurement technologies are making CD4 testing more universally available. Recent evidence suggests that a CD4/CD8 ratio of less than 1 may provide a reliable marker of presumptive HIV-1 infection in HIV-1 exposed infants. This review will summarize the current guidelines for the use of CD4 testing in HIV-1 infected infants and the potential for the CD4:CD8 ratio to be used as a surrogate of HIV-1 infection in resource limited settings. q

show abstract

“…In this context it is worth mentioning the first study performed in Central and Eastern Europe in 1996 on lymphocyte immunophenotyping (41), the consolidated national Belgian experience (42), some important studies on low level leucocyte counting (43,44), on HLA-B27 analysis in Australia and in the Netherlands (45,46), the identification and counting of class-I HLA tetramer-binding CD8þ T cells by the EWGCCA (47), the QASI experience in resource-poor settings, (48) and many others throughout the world.…”

mentioning

confidence: 99%

Twenty years of external quality assurance in clinical cell analysis — A tribute to Jean‐Luc D'Hautcourt

Brando

Gatti

Chianese

et al. 2006

Cytometry Part B Clinical

View full text Add to dashboard Cite

External quality assurance (EQA) denotes the measures taken to ensure the reliability of laboratory sampling, testing, and reporting when test results are to make an impact on clinical decision making (1). EQA in its broader sense is more comprehensive than \external quality control" (EQC), since it includes the important aspects of laboratory proficiency, performance scoring, quality of advice given to clinicians, and continuous educational support.Clinical cell analysis by flow cytometry has entered the same process of development of instrumental validation, internal/external QC, and EQA as any other laboratory medicine activities during the late '80s. The outbreak of the AIDS epidemics, and the need to guide medical treatment with reliable CD4 þ T cell counts have been a stimulus to direct an esoteric, mostly experimental technology towards the same accuracy and reproducibility as has been established for routine blood testing.The progress in establishing a quality assurance process in clinical cell analysis by flow cytometry has been particularly slow, as compared to other fields of clinical pathology, for a number of reasons: the delicacy of instrumentation, the rapidly evolving hardware and software, the continuous development of new biological targets, antibody reagents and fluorochromes, and most important the lacking of any previously existing discipline to encompass all the aspects of clinical cytometry (2).During the last two decades a long and sometimes difficult process took place, complicated by multiple waves of technical development and clinical validation of many different applications such as leukemia/lymphoma immunophenotyping, CD34þ hematopoietic stem cell analysis, screening for the HLA B27 antigen, low level leucocyte counting, and many \niche" applications. The evolution of clinical cell analysis by flow cytometry is a good example of how the advent of a new technology can take advantage from the established laboratory qual-*Correspondence to: Prof. Bruno Brando,

show abstract

Impact of the international program for quality assessment and standardization for immunological measures relevant to HIV/AIDS: QASI

Abstract: Measurements of CD4 T-cell levels

Cited by 45 publications

References 18 publications

Low CD4 ⁺ T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

Low CD4 ⁺ T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

CD4 T cell measurements in the management of antiretroviral therapy-A review with an emphasis on pediatric HIV-infected patients

Twenty years of external quality assurance in clinical cell analysis — A tribute to Jean‐Luc D'Hautcourt

Contact Info

Product

Resources

About

Impact of the international program for quality assessment and standardization for immunological measures relevant to HIV/AIDS: QASI

Abstract: Measurements of CD4 T-cell levels

Cited by 45 publications

References 18 publications

Low CD4 + T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

Low CD4 + T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

CD4 T cell measurements in the management of antiretroviral therapy-A review with an emphasis on pediatric HIV-infected patients

Twenty years of external quality assurance in clinical cell analysis — A tribute to Jean‐Luc D'Hautcourt

Contact Info

Product

Resources

About

Low CD4 ⁺ T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana

Low CD4 ⁺ T-Lymphocyte Values in Human Immunodeficiency Virus-Negative Adults in Botswana