Factors Associated with Sample Rejection for CD4+/CD8+ T Cell Count Analyses at the Kenyatta National Hospital Comprehensive Care Center Laboratory, Kenya

Background: The appropriate time to initiate antiretroviral therapy (ART) in HIV/AIDS patients is determined by measurement of CD4+/CD8+ T cell count. The CD4/CD8+ T cell count is also useful, together with viral load, in monitoring disease progression and effectiveness treatment regimens. Several factors may contribute to sample rejection during the CD4+/CD8+ T cells count, resulting in negative effects on patient management. Objective: Evaluate the causes for CD4+CD8+ T cell count sample rejection at the Kenyatta National Hospital Comprehensive Care Center Laboratory. Method: A retrospective cross-sectional study was conducted between 2018 and 2020. Data was obtained from the “rejected samples” for PartecR FlowCyp flow cytometry file. Designed data collection sheet was used for data capture. A total of 3972 samples were submitted for CD4+/CD8+ T cell count during the study period. Causes for sample rejection were numbered 1 to 12, each representing a reason for sample rejection. Number 1 was sub-categorized into clotted, hemolyzed, short-draw and lipemic. Data was analyzed using excel, and presented using tables, graphs and pie charts. Approval to conduct the study was obtained from KNH/UoN ERC. Results: In the study period, 81/3972 (2.0%) samples were rejected. Samples submitted more than 48 hours after collection were mostly rejected. Other factors included improper collection technique, delayed testing, patient identification error and incorrect use of vacutainer. A combination of clotted samples, specimen submission more than 48 hours caused the most frequent sample rejection, followed with combination of specimen submission more than 48 hours, delayed testing and delayed specimen processing. Together, clotted samples, incorrect vacutainer and poor specimen label caused the least sample rejection. Conclusion: Sample rejection rate for CD4/CD8+ T cell count was relatively low, and multiple factors contributed to rejection. However, improved quality assurance will enable more benefit to patients who seek this test in the laboratory.

Impact of baseline CD4^＋ T cell counts on the efficacy of nevirapinebased highly active antiretroviral therapy in Chinese HIV/AIDS patients： a prospective, multicentric study

Background CD4^＋T cell counts have been used as the indicator of human immunodeficiency virus type 1 （HIV-1） disease progression and thereby to determine when to start highly active antiretroviral therapy （HAART）. Whether and how the baseline CD4^＋T cell count affects the immunological and viral responses or adverse reactions to nevirapine （NVP）-containing HAART in Chinese HIV-1 infected adults remain to be characterized. Methods One hundred and ninety-eight HIV-seropositive antiretroviral therapy （ART）-naive subjects were enrolled into a prospective study from 2005 to 2007. Data were analyzed by groups based on baseline CD4^＋T cell counts either between 100-200 cells/μl or 201-350 cells/μl. Viral responses, immunologic responses and adverse events were monitored at baseline and at weeks 4, 12, 24, 36, 52, 68, 84, 100. Results Eighty-six and 112 subjects ranged their CD4^＋T cell counts 100-200 cells/μl and 201-350 cells/μl, respectively. The pre-HAART viral load in CD4 201-350 cells/μl group was significantly lower than that in CD4 100-200 cells/μl group （P=0.000）. After treatment, no significant differences were observed between these two groups either in the plasma viral load （pVL） or in the viral response rate calculated as the percentage of pVL less than 50 copies/ml or less than 400 copies/ml. The CD4^＋T cell counts were statistically higher in the 201-350 group during the entire follow-ups （P 〈0.01） though CD4^＋ T cell count increases were similar in these two groups. After 100-week treatment, the median of CD4^＋ T cell counts were increased to 331 cells/μl for CD4 100-200 cells/μl group and to 462 cells/μl for CD4 201-350 cells/μl group. Only a slightly higher incidence of nausea was observed in CD4 201-350 cells/μl group （P=0.05） among all adverse reactions, including rash and liver function abnormality. Conclusions The pVLs and viral response rates are unlikely to be associated with the baseline CD4^＋T cell counts. Initiating HAART in Chinese HIV-1 infected patients with higher baseline CD4^＋T cell counts could result in higher total CD4^＋T cell counts thereby achieve a better immune recovery. These results support current guidelines to start HAART at a threshold of 350 cells/μl.

Virological and immunological outcomes in HIV-1-infected Chinese patients treated with a combination of Efavirenz and Indinavir for 48 weeks

Background The incidence of HIV-1-related infection d iseases and the mortality of AIDS have dramatically decreased since highly activ e antiretroviral therapy began to be used clinically in China in 1999. And we in itiated a second clinical trial using a combination of Efavirenz and Indinavir to observe the effects of the immunoreaction.Methods Twenty patients with laboratory-confirmed chronic HIV-1 infection were recruited. Blood samples were collected initially and during the weeks after initiation of treatment. Within 48 hours of blood sampling, peripheral blood plasma and mononuclear cells were separated using routine methods. HIV-1 viral load was measured in thawed plasma samples. Within 48 hours of peripheral blood sampling, CD4 + and CD8 + T cell subsets were enumerated.Results The drug regimen was efficient in reducing HIV-1 plasma viral load and increasing total CD4 + T cell counts. The percentage of CD4 + and CD8 + T cel l subsets expressing CD38 and HLA-DR activation markers was positively correlated with plasma viral load and tended to normalize.Conclusions The combination of Efavirenz and Indinavir was generally well tolerated and efficient at reducing HIV-1 RNA. Furthermore, the treatment improved the immunological function.