Comparison of genotypic and virtual phenotypic drug resistance interpretations with laboratory-based phenotypes among CRF01_AE and subtype B HIV-infected individuals.

HIV drug resistance assessments and interpretations can be obtained from genotyping (GT), virtual phenotyping (VP) and laboratory-based phenotyping (PT). We compared resistance calls obtained from GT and VP with those from PT (GT-PT and VP-PT) among CRF01_AE and subtype B HIV-1 infected patients. GT predictions were obtained from the Stanford HIV database. VP and PT were obtained from Janssen Diagnostics BVBA's vircoType(TM) HIV-1 and Antivirogram®, respectively. With PT assumed as the "gold standard," the area under the curve (AUC) and the Bland-Altman plot were used to assess the level of agreement in resistance interpretations. A total of 80 CRF01_AE samples from Asia and 100 subtype B from Janssen Diagnostics BVBA's database were analysed. CRF01_AE showed discordances ranging from 3 to 27 samples for GT-PT and 1 to 20 samples for VP-PT. The GT-PT and VP-PT AUCs were 0.76-0.97 and 0.81-0.99, respectively. Subtype B showed 3-61 discordances for GT-PT and 2-75 discordances for VP-PT. The AUCs ranged from 0.55 to 0.95 for GT-PT and 0.55 to 0.97 for VP-PT. Didanosine had the highest proportion of discordances and/or AUC in all comparisons. The patient with the largest didanosine FC difference in each subtype harboured Q151M mutation. Overall, GT and VP predictions for CRF01_AE performed significantly better than subtype B for three NRTIs. Although discrepancies exist, GT and VP resistance interpretations in HIV-1 CRF01_AE strains were highly robust in comparison with the gold-standard PT.

The benefit of prothrombin complex concentrate in decreasing neurological deterioration in patients with warfarin-associated intracerebral haemorrhage.

OBJECTIVE: To compare the outcomes of patients with warfarin-associated intracerebral haemorrhage given different treatments to reverse the effect of anticoagulation. DESIGN: Historical cohort study. SETTING: A regional hospital in Hong Kong. PATIENTS: Patients on warfarin who developed intracerebral haemorrhage. INTERVENTIONS: Prothrombin complex concentrate versus fresh frozen plasma treatment. MAIN OUTCOME MEASURES: The primary outcome measures included the international normalised ratio before and after prothrombin complex concentrate treatment and the neurological deterioration in patients with Glasgow Coma Scale score of more than 8/not intubated/not planned for immediate surgery (target group). Secondary outcome measures were haematoma expansion, 7-day and 30-day mortality rates, and 3-month functional outcome. Safety outcome was the occurrence of a thrombotic event after prothrombin complex concentrate treatment within the index admission. RESULTS: Among 33 patients with clearly documented time of infusion of prothrombin complex concentrate, and whose international normalised ratio was checked before and after prothrombin complex concentrate treatment, the mean international normalised ratio was reduced from 2.81 to 1.21 within 24 hours. Within the target group of patients, there was a significantly lower rate of neurological deterioration in the prothrombin complex concentrate group (17.4% of 23 patients) versus fresh frozen plasma group (45.5% of 33 patients) [P=0.027]. In terms of the 7-day mortality, 30-day mortality, and 3-month functional outcome, prothrombin complex concentrate-treated group showed a favourable trend although the difference did not reach a statistical significance. No patient developed thrombotic complications after prothrombin complex concentrate treatment. CONCLUSIONS: Prothrombin complex concentrates can reverse the warfarin effect of prolonged international normalised ratio in a timely manner. It might better improve the outcome of warfarin-associated intracerebral haemorrhage compared with fresh frozen plasma treatment by reduction in neurological deterioration.

Two patterns of cerebral metabolite abnormalities are detected on proton magnetic resonance spectroscopy in HIV-infected subjects commencing antiretroviral therapy.

INTRODUCTION: Cerebral function impairment remains problematic in subjects with chronic human immunodeficiency virus (HIV) infection despite effective combination antiretroviral therapy (cART). Using cerebral proton magnetic resonance spectroscopy ((1)H MRS), we aimed to determine if abnormalities could be detected in neurologically asymptomatic HIV-infected subjects electively commencing cART. METHODS: Therapy-naive, HIV-infected individuals and HIV-uninfected controls underwent (1)H MRS in several anatomical voxels including the mid-frontal grey matter (FGM) and right basal ganglia (RBG). Differences in cerebral metabolite ratios between groups and correlations between immune and virological status were assessed. RESULTS: Forty-six subjects were recruited (26 HIV-infected and 20 control subjects). In the HIV-infected group, mean CD4+ count (SD, cells per microlitre) and plasma HIV RNA (SD, log10 copies per millilitre) were 192 (86) and 4.71 (0.64), respectively. Choline (Cho)/Creatine (Cr) and myoinositol (MI)/Cr ratios were significantly lower in the FGM in HIV-infected subjects compared to controls (0.67 (0.14) versus 0.88 (0.49), p = 0.036, and 0.94 (0.28) and 1.17 (0.26), p = 0.008, for Cho/Cr and MI/Cr, respectively) and Cho/Cr ratio associated with CD4+ lymphocyte count (p = 0.041). N-Acetyl-aspartate (NAA)/Cho ratio was significantly lower in the RBG in HIV-infected subjects compared to controls (2.27 (0.54) versus 2.63 (0.68), p = 0.002), and this was associated with greater plasma HIV RNA load (p = 0.014). CONCLUSIONS: Two patterns of cerebral metabolite abnormalities were observed in HIV-infected subjects electively commencing cART. Greater inflammatory metabolite ratios (Cho/Cr and MI/Cr) associated with lower markers of peripheral immune markers (CD4+ lymphocyte count) in the FGM and lower neuronal metabolite ratios (NAA/Cho) associated with greater HIV viraemia in the RBG were present in HIV-infected subjects.

In-house human immunodeficiency virus-1 genotype resistance testing to determine highly active antiretroviral therapy resistance mutations in Hong Kong.

OBJECTIVE: To determine the frequency of highly active antiretroviral therapy resistance mutations in the viral pol gene of human immunodeficiency virus-1 (HIV-1) genotypes that circulate in Hong Kong, by means of an in-house HIV-1 genotyping system. DESIGN: Retrospective study. SETTING: Two HIV clinics in Hong Kong. PATIENTS: A modified in-house genotyping resistance test was used to sequence the partial pol gene in 1165 plasma samples from 965 patients. The performance of our test was cross-compared with the US Food and Drug Administration-approved ViroSeq HIV-1 genotyping system. The results of genotyping were submitted to the Stanford HIV-1 drug resistance database for analysis. RESULTS: The cost-effective in-house genotypic resistance test (US$40) demonstrated comparable performance to the US Food and Drug Administration-approved ViroSeq system. The detection limit of this in-house genotypic resistance test could reach 400 copies/mL for both HIV-1 subtype B and CRF01_AE, which were the predominant genotypes in Hong Kong. Drug resistance mutations were detected only in post-treatment samples from treatment-failure patients. However, there was no significant difference in the frequency of drug resistance mutations between subtype B and CRF01_AE. CONCLUSION: Our cost-effective in-house genotypic resistance test detected no significant difference in drug resistance-related mutations frequencies between HIV-1 subtype B and CRF01_AE in Hong Kong. A drug resistance-related mutations database for different HIV-1 genotypes should be established in Hong Kong to augment guidance for HIV treatment.

HIV-1 drug resistance mutations among antiretroviral-naive HIV-1-infected patients in Asia: results from the TREAT Asia Studies to Evaluate Resistance-Monitoring Study.

Of 682 antiretroviral-naïve patients initiating antiretroviral therapy in a prospective, multicenter human immunodeficiency virus type 1 (HIV-1) drug resistance monitoring study involving 8 sites in Hong Kong, Malaysia, and Thailand, the prevalence of patients with ≥1 drug resistance mutation was 13.8%. Primary HIV drug resistance is emerging after rapid scaling-up of antiretroviral therapy use in Asia.

Prevalence of and risk factors for lipodystrophy among HIV-infected patients receiving combined antiretroviral treatment in the Asia-Pacific region: results from the TREAT Asia HIV Observational Database (TAHOD).

The prevalence of and risk factors for lipodystrophy (LD) among patients receiving combined antiretroviral treatment (cART) in the Asia-Pacific region are largely unknown. LD diagnosis was based on the adverse event definition from the US NIH Division of AIDS (2004 version), and only cases with a severity grade of ≥ 3 were included. TAHOD patients who had recently commenced cART with ≥ 3 drugs after 1996 from sites which had ever reported LD were included in the analysis. Covariates for the forward multivariate logistic regression model included demographic variables, CDC disease classification, baseline CD4 and viral load, hepatitis B/C virus co-infection, and regimen and duration of cART. LD was diagnosed in 217 (10.5%) of 2072 patients. The median duration of cART was 3.8 (interquartile range, 2.2-5.3) years [stavudine, 2.0 (1.0-3.5) years; zidovudine, 1.8 (0.6-3.9) years; and protease inhibitors (PI), 2.6 (1.3-4.5) years]. In the multivariate model, factors independently associated with LD included use of stavudine (≤ 2 years vs. no experience: OR 25.46, p<0.001, > 2 years vs. no experience: OR 14.92, p<0.001), use of PI (> 2.6 years vs. no experience: OR 0.26, p<0.001), and total duration of cART (> vs. ≤ 3.8 years: OR 4.84, p<0.001). The use of stavudine was strongly associated with LD in our cohort. Stavudine-sparing cART strategies are warranted to prevent the occurrence of LD in the Asia-Pacific region.

Does choice of combination antiretroviral therapy (cART) alter changes in cerebral function testing after 48 weeks in treatment-naive, HIV-1-infected individuals commencing cART? A randomized, controlled study.

BACKGROUND: Neurocognitive impairment remains prevalent, despite combination antiretroviral therapy (cART). Differences between changes in cerebral function and alternative cARTs have not been prospectively assessed. METHODS: Treatment-naive, HIV-1-infected individuals randomly allocated to commence cART (tenofovir-emtricitabine plus either efavirenz [arm 1], atazanavir-ritonavir [arm 2], or zidovudine-abacavir [arm 3]) were eligible. Cerebral function tests included neurocognitive testing and assessment of cerebral metabolites using proton magnetic resonance spectroscopy in several anatomical voxels, including right frontal white matter and right basal ganglia, at baseline and after 48 weeks. N-acetylaspartate-to-creatine (NAA/Cr) ratios were calculated. Both the differences between changes in neurocognitive function and NAA/Cr ratios over 48 weeks and the study arms (arm 1 vs arm 2; arm 1 vs arm 3) were assessed. RESULTS: Thirty subjects completed study procedures (9, 9, and 12 subjects in arms 1, 2, and 3, respectively). Mean CD4+ cell counts (+/- standard deviation) were 218 +/- 87 cells/microL at baseline and 342 +/- 145 cells/microL at week 48. The mean plasma HIV-1 RNA level was <50 copies/mL for 28 of the 30 subjects at week 48. Over 48 weeks, greater improvements in identification reaction time (P = .04) and executive function (P = .02) were observed in arm 3, compared with arm 1 (0.03, -0.30, -0.50 log10 ms change in identification reaction time, in arms 1, 2, and 3, respectively). Increases in the NAA/Cr ratio were observed in all voxels (maximum 38% in right basal ganglia), with greater increases observed in arm 1 than in arm 2 (P = .03) in frontal white matter (30%, -7%, and 0% change in the NAA/Cr ratio, in arms 1, 2, and 3, respectively). CONCLUSIONS: To our knowledge, this is the first study to prospectively describe different changes in cerebral function testing parameters between different cARTs. Greater improvements in neuronal recovery (NAA/Cr ratio) were observed for recipients of tenofovir-emtricitabine plus efavirenz (arm 1), and greater improvements in neurocognitive function testing were observed for recipients of tenofovir-emtricitabine plus zidovudine-abacavir (arm 3).

Trends in CD4 counts in HIV-infected patients with HIV viral load monitoring while on combination antiretroviral treatment: results from The TREAT Asia HIV Observational Database.

BACKGROUND: The aim of this study was to examine the relationship between trends in CD4 counts (slope) and HIV viral load (VL) after initiation of combination antiretroviral treatment (cART) in Asian patients in The TREAT Asia HIV Observational Database (TAHOD). METHODS: Treatment-naive HIV-infected patients who started cART with three or more and had three or more CD4 count and HIV VL tests were included. CD4 count slopes were expressed as changes of cells per microliter per year. Predictors of CD4 count slopes from 6 months after initiation were assessed by random-effects linear regression models. RESULTS: A total of 1676 patients (74% male) were included. The median time on cART was 4.2 years (IQR 2.5-5.8 years). In the final model, CD4 count slope was associated with age, concurrent HIV VL and CD4 count, disease stage, hepatitis B or C co-infection, and time since cART initiation. CD4 count continues to increase with HIV VL up to 20,000 copies/mL during 6-12 months after cART initiation. However, the HIV VL has to be controlled below 5,000, 4,000 and 500 copies/mL for the CD4 count slope to remain above 20 cells/microliter per year during 12-18, 18-24, and beyond 24 months after cART initiation. CONCLUSIONS: After cART initiation, CD4 counts continued to increase even when the concurrent HIV VL was detectable. However, HIV VL needed to be controlled at a lower level to maintain a positive CD4 count slope when cART continues. The effect on long-term outcomes through the possible development of HIV drug resistance remains uncertain.

Profiling advanced disease in an Asian clinical human immunodeficiency virus cohort: comparison of two definitions for acquired immunodeficiency syndrome.

OBJECTIVE: To compare advanced human immunodeficiency virus disease defined immunologically and clinically by evaluating the characteristics of human immunodeficiency virus patients in Hong Kong. DESIGN: Retrospective observational study. SETTING: A human immunodeficiency virus cohort database established at a university and the major human immunodeficiency virus specialist services in Hong Kong. PATIENTS: Patients diagnosed with acquired immunodeficiency syndrome at the study centres between 1985 and 2006 were included. MAIN OUTCOME MEASURES: Comparison of advanced human immunodeficiency virus disease defined (a) clinically as World Health Organization stage IV, and (b) immunologically as a CD4 count lower than 350/microL. RESULTS: Between 1985 and 2006, a total of 1317 patients, a majority of whom Chinese, were evaluated. Of these, 914 (69%) and 335 (25%) fulfilled the criteria for immunologically and clinically defined advanced disease, respectively. The mean age of the study population was 38 years and male-to-female ratio 4:1. There were two peaks in the frequency distribution of CD4 counts, one at a low count of less than 100/microL and the other between 200 and 400/microL. All except four with clinically defined advanced disease had CD4 counts lower than 350/microL on presentation. Of those with immunologically defined advanced disease, men having sex with men accounted for a lower proportion in the clinically advanced category, and Pneumocystis pneumonia was the commonest advanced disease at presentation. CONCLUSIONS: Both clinical and immunological definitions provide a consistent means for assessing advanced disease, the implications of which are different. Such profiling has been made possible through the operation of a standardised cohort database, which is useful in (1) enhancing human immunodeficiency virus epidemiology studies, and (2) evaluating the performance of public health services.

Short-term clinical disease progression in HIV-infected patients receiving combination antiretroviral therapy: results from the TREAT Asia HIV observational database.

OBJECTIVE: The aim of our study was to develop, on the basis of simple clinical data, predictive short-term risk equations for AIDS or death in Asian patients infected with human immunodeficiency virus (HIV) who were included in the TREAT Asia HIV Observational Database. METHODS: Inclusion criteria were highly active antiretroviral therapy initiation and completion of required laboratory tests. Predictors of short-term AIDS or death were assessed using Poisson regression. Three different models were developed: a clinical model, a CD4 cell count model, and a CD4 cell count and HIV RNA level model. We separated patients into low-risk, high-risk, and very high-risk groups according to the key risk factors identified. RESULTS: In the clinical model, patients with severe anemia or a body mass index (BMI; calculated as the weight in kilograms divided by the square of the height in meters)