Cost savings by reagent reduction in flow cytometry-based CD4+ T cell counts: an approach to improve accessibility for HIV management.

In Thailand, the cost of antiretrovirals has recently been reduced more than 10 fold. Likewise strategies for a cost reduction in laboratory monitoring are warranted. This study was designed to explore if the most expensive reagent in flow cytometry based CD4+ cell monitoring, the CD4+/CD8+ monoclonal antibodies, can be reduced without a loss of accuracy. Blood samples from 55 HIV seronegative (HIV-) and 76 HIV+ subjects were analyzed for %CD4+ and %CD8+ T cells using a two color monoclonal antibody panel (BD Biosciences, CA, USA) with 3 different amounts of the recommended reagents for staining: 1) standard, 2) half, and 3) one-fourth. A significant Spearman correlation of 0.987 was shown for the % CD4+ T cell test results for one half as well as one-fourth of the recommended amount compared to the standard staining according to the manufacturer's instruction (p < 0.0001). For the % CD8+ T cell test results, the correlation between the standard and the half or one-fourth reduced staining was 0.972 (p < 0.0001). Bland-Altman analysis showed no significant bias between the results from one half or one-fourth of the recommended amount versus the standard. The sensitivity and specificity of the two methods at the CD4+ T cell count cut-off of 200 cells/microl were 93% and 100%; and 96% and 99%, respectively. Our study indicates that a reduction of the reagents to half or one-fourth of the amount recommended by the manufacturer was still able to generate reliable results for CD4+ and CD8+ T cell counts. Such an approach will significantly reduce the cost of CD4+ monitoring for resource limited settings where a flow cytometer is available.

High prevalence of indinavir-associated renal complications in Thai HIV-infected patients.

BACKGROUND: Indinavir (IDV) is the protease inhibitor (PI) used most often in resource-limited countries. The present study aimed to determine the prevalence of IDV-associated renal complications as well as their clinical characteristics. MATERIAL AND METHOD: The authors reviewed all patients participating in cohorts of indinavir-containing regimens at the HIV-NAT research center during the period of indinavir treatment. Patients who had pre-existing renal diseases were excluded. Renal toxicities included presence of urologic symptoms, nephrolithiasis, abnormal urine sediments, crystalluria and loss of renal function. Radiological studies of KUB system were reviewed as well. RESULTS: Two-hundred and four patients treated with IDV were included. Median (IQR) follow up period was 216 (150-312) weeks. One hundred and eighty patients were treated with ritonavir-boosted regimens at some point, and 24 patients were treated only with unboosted regimens. Leukocyturia (51.9%) was the most common finding of IDV-associated renal complications. Thirty-five percent of patients had urologic symptoms such as flank pain or dysuria. Almost half of the patients had significant loss of renal function that was associated with prolonged use of IDV The most common radiological finding was nephrolithiasis. Less common, but of greater clinical importance, are nephrocalcinosis or renal atrophy. CONCLUSION: A high prevalence of IRC was found in Thai HIV-infected patients. As long as no other cost-effective boosted PI regimens are available, strategies to prevent irreversible loss of renal function are warranted.

No effect of interleukin-2 on IgE levels given in addition to antiretroviral therapy in HIV-infected adults with CD4 >300 cells/mm3.

HIV-infected patients may have frequent atopy caused by an imbalance of Th1 and Th2 cytokines. The objective of the present study was to investigate whether IL-2 given in addition to antiretrovirals (ARV) would result in lower IgE levels and less allergic symptoms. Patients naive to IL-2 (n=28) began IL-2 plus ARV and were followed for 12 months. IgE, eosinophil and CD4 counts, HIV RNA, symptom scoring, PFT and skin prick test (SPT) were performed. It was found that the baseline median CD4 and IgE were 386.5 cells/mm3 and 63.5 IU/ml, respectively. Four patients had allergic rhinitis (AR) and 61% had a positive SPT to at least 1 antigen. At month 12, patients had higher CD4 counts (p < 0.001) compared to the baseline; however, there were no differences in IgE levels, allergic symptom scores or HIV RNA. The eosinophil count was higher after IL-2 administration. It was concluded that IL-2 plus ARV resulted in higher CD4 counts but had no effect on atopy.

Undetectable plasma HIV-1 RNA with strong gag-pol specific interferon-gamma ELISPOT response in an HIV-1 clade A/E-infected child untreated with antiretroviral therapy.

We report a 7-year HIV-1 clade A/E-infected child untreated with antiretroviral therapy who had positive HIV antibody testing but undetectable plasma HIV-1 RNA by Roche Amplicor version 1.5 and bDNA version 3.0. DNA PCR was positive by methods using gag/pol primers but not env/pol primers. The patient had strong HIV-1-specific cytotoxic T lymphocyte responses, which likely contributed to her low viral burden and undetectable plasma HIV-1 RNA.

Significant differences between plasma HIV-1 RNA assays in HIV-1 subtype E infected patients treated with antiretroviral therapy.

A total of 72 HIV-1 infected Thai patients treated with didanosine (ddI) or stavudine (d4T) plus ddI at the time of interim analysis were analyzed. Sixty patients (83%) carried subtype E documented by HIV-1 V3 serotyping. HIV-1 RNA levels were measured using three commercial viral load assays. At baseline (n = 57), Quantiplex 2.0 and NucliSens 2.0 showed mean log10 HIV-1 RNA of 0.7 log10 or 5 fold lower than Amplicor 1.5 (mean 4.29 versus 5.0 log10, respectively, p < 0.001). At week 20 of treatment (n = 29), HIV-1 RNA levels were detected in 55.2%, 31%, and 33.5% of subjects tested by Amplicor 1.5, Quantiplex 2.0, and NucliSens 2.0, respectively. In conclusion: plasma HIV-1 RNA analyses showed comparable values with Quantiplex 2.0 and NucliSens 2.0 assays. In contrast, Amplicor 1.5 resulted in approximately 5 folds higher HIV-1 RNA levels and a 25% higher rate of detection of plasma HIV-1 RNA as compared to the other two assays. As the current goal of therapy is to suppress plasma viral load below the detection limit of the assays, the significant differences between the assays may influence antiretroviral efficacy evaluation and management.