Evaluation of a Low-Cost Method, the Guava EasyCD4 Assay, to Enumerate CD4-Positive Lymphocyte Counts in HIV-Infected Patients in the United States and Uganda

Spacek, Lisa A.; Shihab, Hasan M; Lutwama, Fred; Summerton, Jean; Mayanja, Harriet; Ronald, Allan; Margolick, Joseph B.; Nilles, Tricia L.; Quinn, Thomas C.

doi:10.1097/01.qai.0000214807.98465.a2

Cited by 33 publications

(32 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[104][105][106] Similarly microcapilliary flow-based systems, CD4+ chips, or total white counts (panleucocyte gating) provide alternatives for establishment of the level of immunodeficiency in resource-limited settings. [107][108][109][110] Drug treatment…”

Section: Clinical Management Diagnosismentioning

confidence: 99%

HIV/AIDS epidemiology, pathogenesis, prevention, and treatment

2006

View full text Add to dashboard Cite

The HIV-1 pandemic is a complex mix of diverse epidemics within and between countries and regions of the world, and is undoubtedly the defining public-health crisis of our time. Research has deepened our understanding of how the virus replicates, manipulates, and hides in an infected person. Although our understanding of pathogenesis and transmission dynamics has become more nuanced and prevention options have expanded, a cure or protective vaccine remains elusive. Antiretroviral treatment has transformed AIDS from an inevitably fatal condition to a chronic, manageable disease in some settings. This transformation has yet to be realised in those parts of the world that continue to bear a disproportionate burden of new HIV-1 infections and are most a % ected by increasing morbidity and mortality. This Seminar provides an update on epidemiology, pathogenesis, treatment, and prevention interventions pertinent to HIV-1. HIV pandemicAn estimated 38·6 (33·4-46·0) million people live with HIV-1 worldwide, while about 25 million have died already. 1 In 2005 alone, there were 4·1 million new HIV-1 infections and 2·8 million AIDS deaths. 1 These estimates mask the dynamic nature of this evolving epidemic in relation to temporal changes, geographic distribution, magnitude, viral diversity, and mode of transmission. Today, there is no region of the world untouched by this pandemic (figure 1). 2 Heterosexual transmission remains the dominant mode of transmission and accounts for about 85% of all HIV-1 infections. Southern Africa remains the epicentre of the pandemic and continues to have high rates of new HIV-1 infections. 3 Although overall HIV-1 prevalence remains low in the emerging epidemics in China and India, the absolute numbers, which are fast approaching those seen in southern Africa, are of concern. 1 Outside of sub-Saharan Africa, a third of all HIV-1 infections are acquired through injecting drug use, most (an estimated 8·8 million) of which are in eastern Europe and central and southeast Asia. 1 The rapid spread of HIV-1 in these regions through injecting drug use is of importance, since it is a bridge for rapid establishment of more generalised epidemics. NIH-PA Author ManuscriptA defining feature of the pandemic in the current decade is the increasing burden of HIV-1 infections in women, 4 which has additional implications for mother-to-child transmission. Women now make up about 42% of those infected worldwide; over 70% of whom live in sub-Saharan Africa. 1 Overall, a quarter of all new HIV-1 infections are in adults aged younger than 25 years. 1 HIV-1 infection rates are three to six times higher in female adolescents than in their male counterparts, 1,5-7 and this difference is attributed to sexual coupling patterns of young women with older men. Population prevalence of HIV-1 infection, concurrent sexual relationships, partner change, sexual practices, the presence of other sexually transmitted diseases, [8][9][10][11] and population mobility patterns 12-14 for economic and other reasons (eg, natu...

show abstract

Section: Clinical Management Diagnosismentioning

confidence: 99%

HIV/AIDS epidemiology, pathogenesis, prevention, and treatment

2006

View full text Add to dashboard Cite

show abstract

“…The manual methods are being used in settings where flow cytometry may not be appropriate; the major (and significant) limitation is the number of tests that can be run each day. Newer simplified flow cytometers such as the Easy CD4 assay (Guava Technologies, Hayward, California, USA) [24][25][26][27], PointCare NOW (PointCare Technologies, Marlborough, Massachusetts, USA) [28], FACSCount (Becton Dickinson, Franklin Lakes, New Jersey, USA), CyFlow Counter, CyFlow SL green and CyFlow SL blue (Partec, Mü nster, Germany) [21,23,[29][30][31][32][33] are less expensive and less complex to run than traditional flow cytometers, but they are not able to run as many samples as traditional flow cytometers. Most flow cytometers will provide absolute CD4 cell counts as well as CD4 percentage, an important parameter for the monitoring of infants and children with HIV.…”

Section: Cd4 Cell Enumerationmentioning

confidence: 99%

Research needs and challenges in the development of HIV diagnostic and treatment monitoring tests for use in resource-limited settings

Cheng¹,

Landay

Miller³

2008

Current Opinion in HIV and AIDS

View full text Add to dashboard Cite

Increased availability of antiretroviral therapy in resource-limited settings increases the need for reliable, less costly and simpler to use HIV diagnostic and treatment monitoring technologies. Global leadership is needed to coordinate the research and development necessary to ensure that HIV diagnostic and treatment monitoring technologies are properly evaluated in the setting where they will be used.

show abstract

“…The Guava Easy CD4 Assay (Guava technologies, Hayward California) enumerates the same lymphocyte subsets and has comparable equipment costs to the FACSCount system, but it utilizes microcapillary cytometry, minimal reagent and no sheath fluid; hence the total cost is lower than FACSCount assay. Importantly, the CD4þ T cell counts by both methods were shown to be highly correlated in a United States (n 5 77) and a Ugandan (n 5 141) cohort (50). Other relatively low-cost methods with excellent correlation with flow cytomeric enumeration of CD4þ T cells have been validated (51)(52)(53)(54)(55).…”

Section: Access In Sub-saharan Africamentioning

confidence: 99%

Clinical applications and availability of CD4+ T cell count testing in sub-Saharan Africa

Taiwo

Murphy

2008

Cytometry

View full text Add to dashboard Cite

The absolute CD41 T cell count in adults and CD41 T cell percentage of lymphocytes (CD4%) in pediatrics compliment clinical history and physical examination to inform decisions about initiating antiretroviral therapy (ART). In addition, these immunologic markers predict host susceptibility to specific opportunistic infections, selected drug toxicities, and mortality. These benefits argue strongly for the availability of CD41 T cell testing capacity in all settings where HIV infection is treated. Several currently available flow cytometry-based devices, and novel CD41 T cell enumeration techniques such as the panleucogating CD4 are especially suitable for resource-constrained settings.At this time, unfortunately, the landscape of HIV care in sub-Saharan Africa is a mosaic characterized by large areas where CD41 T cell testing capacity is limited or unavailable, and small, but growing, pockets where the capacity exists. Routine HIV quantification is currently unaffordable and unsustainable in the great majority of the region; therefore, a reliance on CD41 T cell testing is inevitable for now. To this end, correcting the disparities in CD41 T cell testing capacity and defining the minimum laboratory requirements for the safe use of antiretroviral drugs through well-designed clinical studies are some of the most urgent priorities of the ongoing global scale-up of ART. q 2007 Clinical Cytometry Society

show abstract

Evaluation of a Low-Cost Method, the Guava EasyCD4 Assay, to Enumerate CD4-Positive Lymphocyte Counts in HIV-Infected Patients in the United States and Uganda

Abstract: Our results suggest that EasyCD4 may be used with high positive and negative predictive value in resource-limited settings.

Cited by 33 publications

References 9 publications

HIV/AIDS epidemiology, pathogenesis, prevention, and treatment

HIV/AIDS epidemiology, pathogenesis, prevention, and treatment

Research needs and challenges in the development of HIV diagnostic and treatment monitoring tests for use in resource-limited settings

Clinical applications and availability of CD4+ T cell count testing in sub-Saharan Africa

Contact Info

Product

Resources

About