Protease inhibitors atazanavir, lopinavir and ritonavir are potent blockers, but poor substrates, of ABC transporters in a broad panel of ABC transporter-overexpressing cell lines.

OBJECTIVES: A possible mechanism for HIV therapy failure is the efflux of HIV drugs from viral target cells or certain body compartments by ATP-binding cassette (ABC) transporters, allowing ongoing viral replication. Here, we investigated the interaction between protease inhibitors (PIs) and ABC transporters. METHODS: To explore the potential blocking capacity of PIs, we exposed cells overexpressing multidrug resistance 1 P-glycoprotein (MDR1 P-gp), multidrug resistance protein 1 (MRP1) and breast cancer resistance protein (BCRP) to established cytotoxic substrates with or without one of the PIs atazanavir, lopinavir or ritonavir. Furthermore, to assess whether PIs serve as substrates, cell growth-inhibitory effects of these PIs were evaluated on cells overexpressing 1 of 11 ABC transporters and their parental counterparts. RESULTS: Atazanavir, lopinavir and ritonavir were highly effective in reversing resistance against established substrates in cells overexpressing MDR1 P-gp and MRP1, and, to a lesser extent, BCRP. Concurrently, however, PIs appeared to be relatively poor substrates for ABC transporters. Only a moderate level of resistance to atazanavir was observed in cells overexpressing MRP6 and MRP9 [resistance factor (RF): 2.0-2.6]. Cells overexpressing MDR1 P-gp, MRP3, MRP4 and MRP5 displayed low levels of resistance to atazanavir (RF: 1.3-1.7); MRP7- and MRP9-overexpressing cells to lopinavir (RF: 1.4-1.5); and MRP9-overexpressing cells to ritonavir (RF: 1.4). CONCLUSIONS: PIs can act as potent blockers of MDR1 P-gp, MRP1 and BCRP, but they are poor substrates for 11 ABC transporters. Consequently, ABC transporters are unlikely to play a major role in PI failure, but still may contribute to drug-specific adverse events and drug-drug interactions.

Comparison of the risks of atherosclerotic events versus death from other causes associated with antiretroviral use.

BACKGROUND: Studies considering the risk of atherosclerotic disease (AtD) associated with the use of HAART have reported inconsistent results. METHODS: Data on antiretroviral therapy (ART) use, risk factors for cardiovascular disease (CVD), AtD and death from other causes in 18 603 HIV-infected patients from two established cohorts were evaluated. The relative hazards of AtD and death from other causes were calculated using a proportional hazards competing risks framework. The impact of protease inhibitor (PI)-containing, non-nucleoside reverse transcriptase inhibitor (NNRTI)-containing or PI + NNRTI-containing regimens on these outcomes were compared to nucleoside reverse transcriptase inhibitor (NRTI)-only regimens or stopping therapy, adjusting for known CVD risk factors. RESULTS: In 77 480 person-years of follow-up (median duration 3.49 years) there were 318 AtD events including 92 myocardial infarctions and 2044 deaths. Older age, hypertension, diabetes mellitus, having smoked and HIV disease stage were significantly associated with increased risk of AtD. PI- and NNRTI-containing regimens significantly reduced the joint risk of either AtD or death from other causes compared to NRTI-only or stopping therapy [hazard ratio (HR) for PI-containing ART, 0.76, 95% confidence interval (CI), 0.73-0.78, P< 0.001; NNRTI-containing ART, 0.69, 95% CI, 0.65-0.74; P< 0.001). PI-containing ART was associated with a borderline significant increased risk of myocardial infarction (cause-specific HR for PI-containing ART 1.19, 95% CI, 1.01-1.40, P = 0.04) but not with increased risk of AtD compared to NRTI-only regimens or stopping therapy (cause-specific HR for PI-containing ART, 1.03, 95% CI, 0.95-1.13, P = 0.44). CONCLUSIONS: Overall benefits of PI- and NNRTI-based ART in reducing mortality significantly outweigh any risks of AtD in the "short-term" follow-up of this study. Traditional cardiac risk factors play an important role in determining AtD risk status.

TMC125 exerts similar initial antiviral potency as a five-drug, triple class antiretroviral regimen.

OBJECTIVE: TMC125, a next generation, non-nucleoside reverse transcriptase inhibitor (NNRTI), demonstrated a remarkable decline of plasma HIV-1 RNA during a phase IIa study. We compared the initial rate of decline of plasma HIV-1 RNA achieved by TMC125 monotherapy with that of a triple class, five-drug regimen, containing drugs from all three currently licensed classes (zidovudine, lamivudine, abacavir, indinavir and nevirapine). METHODS: The decline in plasma HIV-1 RNA of 12 HIV-1 infected, antiretroviral (ART) naive patients treated for 1 week with TMC125 monotherapy was compared with that observed in the ERA study (n = 11). The plasma HIV-1 RNA elimination rate constant was calculated based on at least four plasma HIV-1 RNA measurements during the first week of treatment (first-order elimination) and compared using the Student's t test. RESULTS: Median ages were 23 and 38 years for TMC125 and ERA patients, respectively (P = 0.001), median baseline plasma HIV-1 RNA levels were 4.2 and 4.8 log10 copies/ml (P = 0.001) and median baseline CD4 T-cell counts were 458 x 10(6) and 360 x 10(6) cells/l (P = 0.08). The median plasma HIV-1 RNA elimination rate constant was 0.68/day in TMC125 treated patients, and 0.56/day in ERA participants (P = 0.24). The median decline in plasma HIV-1 RNA after 7 days was 1.92 and 1.76 log10 copies (P = 0.77) and the median increase of CD4 T cells was 119 x 10(6) and 60 x 10(6) cells/l, respectively (P = 0.29). CONCLUSION: Monotherapy with TMC125 in ART-naive, HIV-1-infected individuals resulted in a similar rate of decline of plasma HIV-1 RNA during 1 week of therapy as therapy with a five-drug regimen.

Clinical, immunological and virological response to different antiretroviral regimens in a cohort of HIV-2-infected patients.

OBJECTIVE: To assess the clinical, immunological and virological response and the emergence of resistance towards antiretroviral therapy (ART) in a cohort of HIV-2-infected patients. DESIGN: Observational study. PATIENTS: HIV-2-infected patients residing in the Netherlands. RESULTS: From 1995 to 2001 seven patients failed various ART regimens. The resistance mutations were analysed retrospectively. Development of mutations proved to be similar to that observed in HIV-1-infected patients, with the exception of a higher occurrence of the Q151M mutation within the reverse transcriptase gene. In a prospective study, comprising 13 consecutive naive HIV-2-infected patients, all patients achieved plasma HIV-2-RNA suppression below the detection limit (500 copies/ml). The antiretroviral regimen consisted of two nucleoside reverse transcriptase inhibitors (NRTIs) and indinavir, with a boosting dose of ritonavir; the median follow-up was 91 weeks. Two patients experienced a temporary virological rebound, while at the same time therapeutic drug monitoring showed sub-therapeutic plasma levels of indinavir. CONCLUSION: Sustained viral suppression in HIV-2-infected patients can be achieved using an antiretroviral regimen of two NRTIs and boosted indinavir or lopinavir.

New developments in the diagnosis of bloodstream infections.

New techniques have emerged for the detection of bacteria in blood, because the blood culture as gold standard is slow and insufficiently sensitive when the patient has previously received antibiotics or in the presence of fastidious organisms. DNA-based techniques, hybridisation probes, and PCR-based detection or protein-based detection by mass spectroscopy are aimed at rapid identification of bacteria and provide results within 2 h after the first signal of growth in conventional blood cultures. Also, detection of microorganisms directly in blood by pathogen-specific or broad-range PCR assays (eubacterial or panfungal) shows promising results. Interpretation is complex, however, because of detection of DNA rather than living pathogens, the risk of interfering contamination, the presence of background DNA in blood, and the lack of a gold standard. As these techniques are emerging, clinical value and cost-effectiveness have to be assessed. Nevertheless, molecular assays are expected eventually to replace the current conventional microbiological techniques for detection of bloodstream infections.

Detection of bacterial DNA in blood samples from febrile patients: underestimated infection or emerging contamination?

We applied real-time broad-range polymerase chain reaction (PCR) to detect bacteraemia in blood from febrile patients. Interpretation of amplification results in relation to clinical data and blood culture outcome was complex, although the reproducibility of the PCR results was good. Sequencing analysis of the PCR products revealed the presence of Burkholderia species DNA while no Burkholderia species grew in culture. The source of this contamination was shown to be the commercial DNA isolation kit used in the automated MagNA Pure Isolation Robot. A high degree of suspicion is required when uncommon or unexpected pathogens are diagnosed by molecular methods as clinical consequences can be serious.

Post-exposure prophylaxis.

The mean risk of acquiring HIV after an occupational exposure, injecting drug use or sexual exposure varies from < 0.1 to 3%. A high plasma HIV-RNA of the source increases the risk of each of the exposures. Other factors, such as the volume of the inoculum involved to which the individual was exposed, other sexually transmitted diseases and ruptures of mucous membranes are associated with a higher risk of HIV transmission. Based on the calculated risk, post-exposure prophylaxis (PEP) should be recommended. In the Netherlands, prescription of PEP in the occupational setting is a standard procedure and has proved to be feasible. This was associated with a high percentage (62%) of mild and reversible toxicity and a small percentage (2%) of serious adverse events related to antiretroviral drugs, i.e. nephrolithiasis (due to indinavir) and toxic hepatitis (due to nevirapine). In The Netherlands so far no HIV-seroconversions have been recorded after an occupational accident.

Prevalence and determinants for malnutrition in geriatric outpatients.

BACKGROUND & AIMS: Few data is available on the nutritional status of geriatric outpatients. The aim of this study is to describe the nutritional status and its clinical correlates of independently living geriatric older individuals visiting a geriatric outpatient department. METHODS: From 2005 to 2010, all consecutive patients visiting a geriatric outpatient department in the Netherlands were screened for malnutrition. Nutritional status was assessed by the Mini Nutritional Assessment (MNA). Determinants of malnutrition were categorized into somatic factors (medicine use, comorbidity, walking aid, falls, urinary incontinence), psychological factors (GDS-15 depression scale, MMSE cognition scale), functional status (Activities of Daily Life (ADL), Instrumental ADL (IADL)), social factors (children, marital status), and life style factors (smoking, alcohol use). Univariate and multivariate logistic regression analyses, adjusted for age and sex and all other risk factors were performed to identify correlates of malnutrition (MNA < 17). RESULTS: Included were 448 outpatients, mean (SD) age was 80 (7) years and 38% was men. Prevalence of malnutrition and risk for malnutrition were 17% and 58%. Depression, being IADL dependent, and smoking were independently associated with an increased risk of malnutrition with OR's (95%CI) of 2.6 (1.3-5.3), 2.8 (1.3-6.4), 5.5 (1.9-16.4) respectively. Alcohol use was associated with a decreased risk (OR 0.4 (0.2-0.9)). CONCLUSION: Malnutrition is highly prevalent among geriatric outpatients and is independently associated with depressive symptoms, poor functional status, and life style factors. Our results emphasize the importance of integrating nutritional assessment within a comprehensive geriatric assessment. Future longitudinal studies should be performed to examine the effects of causal relationships and multifactorial interventions.

Zidovudine/lamivudine but not nevirapine in combination with lopinavir/ritonavir decreases subcutaneous adipose tissue mitochondrial DNA.

OBJECTIVE: No randomized study has prospectively followed subcutaneous adipose tissue mitochondrial DNA (mtDNA) changes when starting thymidine nucleoside reverse transcriptase inhibitors (tNRTIs). DESIGN: The Metabolic Effects of DIfferent CLasses of AntiretroviralS study randomized HIV-positive, treatment-naive male participants to start lopinavir/ritonavir (LPVr) with either zidovudine/lamivudine (ZDV/3TC) or nevirapine (NVP). METHODS: Regional body fat was assessed by dual energy x-ray absorptiometry and abdominal computed tomography at months 0, 3, 12, 24 and 36. In a molecular substudy, subcutaneous adipose tissue (SAT) biopsies were taken, with mtDNA quantified by quantitative PCR. Data were analyzed using repeated measures linear regression analyses. RESULTS: Of 50 participants recruited (23 to LPVr/ZDV/3TC), 48 started therapy, and 37 participants (19 on LPVr/ZDV/3TC) enrolled in the substudy. At 36 months, the LPVr/ZDV/3TC group had significantly lower limb fat [6.4 kg (0.26) versus 7.3 kg (0.31), P = 0.017] and a trend toward lower abdominal SAT compared to the LPVr/NVP group [131 cm (6.86) versus 146 cm (6.33), P = 0.097]. Over 36 months, mtDNA declined in the LPVr/ZDV/3TC group [mtDNA region 1: -190 (95) copies/cell, P = 0.053, region 2: -269 (106) copies/cell, P = 0.016] but not within the LPVr/NVP group [region 1: +28 (99) copies/cell, P = 0.78, region 2: +51 (111) copies/cell, P = 0.65, between-group difference P < 0.01 for both measurements]. mtDNA was significantly lower in the LPVr/ZDV/3TC group at 36 months. CONCLUSION: This is the first randomized study to prospectively demonstrate reductions in SAT mtDNA in patients initiating ZDV/3TC-containing antiretroviral therapy (ART) but not in those initiating nucleoside reverse transcriptase inhibitor-sparing ART containing NVP and protease inhibitor. That reductions in SAT mtDNA were also accompanied by lower limb fat suggests that use of ART not containing ZDV/3TC may help prevent development of peripheral lipoatrophy.

The lopinavir/ritonavir-associated rise in lipids is not related to lopinavir or ritonavir plasma concentration.

BACKGROUND: The relationship between lopinavir plasma concentration and the magnitude of lipid elevation after initiation of lopinavir/ritonavir-containing antiretroviral therapy is unclear. The aim of this study was to determine the relationship between drug concentration and lipid changes in two patient cohorts. METHODS: First, we analysed, in an outpatient cohort, the correlation between percentage lipid changes and lopinavir concentration, measured at least 2 weeks or more after initiation of lopinavir/ritonavir. Second, we analysed the correlation between lipid changes and lopinavir and ritonavir plasma concentrations in antiretroviral-naive patients enrolled in a trial comparing nevirapine plus lopinavir/ritonavir (533/133 mg twice daily) with zidovudine/lamivudine plus lopinavir/ritonavir (400/100 mg twice daily). RESULTS: In 82 outpatients with 215 lopinavir plasma measurements, we found no significant correlations between lopinavir concentration and changes in lipids a median of 522 days after lopinavir/ritonavir initiation in univariable regression analyses, nor in multivariable analyses adjusting for potential confounders. In 40 trial samples collected 24 months after treatment initiation, the mean (95% CI) percentage increase in low-density lipoprotein cholesterol (LDLc) was significantly greater in the nevirapine/lopinavir/ritonavir group (29.4% [16.8-43.3]) than in the zidovudine/lamivudine/lopinavir/ritonavir group (6.8% [-7.3-23.1]; P=0.03). However, the percentage LDLc change did not correlate with lopinavir or ritonavir concentration ratios (r=-0.25; P=0.17 and r=-0.06; P=0.75). Adding lopinavir or ritonavir concentrations into the multivariable regression analyses did not change the relation between LDLc change and randomized treatment. CONCLUSIONS: Neither in an HIV outpatient clinic cohort nor in a trial comparing two lopinavir/ritonavir-containing therapies did we find any relation between changes in lipids, and lopinavir and ritonavir concentration, after initiating lopinavir/ritonavir-containing treatment.

Insulin sensitivity in multiple pathways is differently affected during zidovudine/lamivudine-containing compared with NRTI-sparing combination antiretroviral therapy.

OBJECTIVE: The extent and manner by which HIV nucleoside reverse transcriptase inhibitors contribute to insulin resistance is unclear. We evaluated the effect of zidovudine/lamivudine (ZDV/3TC) on glucose metabolism. METHODS: combination antiretroviral therapy-naive men were randomized to lopinavir/ritonavir (LPV/r, 400/100 mg twice a day) + ZDV/3TC or LPV/r (533/133 mg twice a day) + nevirapine (NVP). Computerized tomography, dual-energy X-ray absorptiometry scans, and hyperinsulinemic euglycemic clamps using stable isotopes were performed before and after 3, 12, and 24 months of combination antiretroviral therapy. RESULTS: Insulin-stimulated peripheral glucose disposal decreased by 25% after 3 months in patients on zidovudine/lamivudine/lopinavir/ritonavir (ZDV/3TC/LPV/r) (P < 0.001) and this decreased rate persisted thereafter, followed by a transient decrease in insulin-mediated inhibition of lipolysis. In the nevirapine/lopinavir/ritonavir (NVP/LPV/r) group, hepatic insulin sensitivity had improved compared with baseline after 24 months. After the initial 3 months, limb fat decreased in the ZDV/3TC/LPV/r arm up to 24 months [-849 +/- 345 g (P = 0.017)], and visceral adipose tissue increased over 2 years [+36.2 +/- 13.3 cm2 (P = 0.009)]. In the NVP/LPV/r group, a generalized increase in fat mass was observed. CONCLUSIONS: Treatment with ZDV/3TC/LPV/r versus NVP/LPV/r differentially affects glucose and lipid metabolism. The ZDV/3TC/LPV/r regimen induced peripheral insulin resistance, a transient increase in basal lipolysis and a transient decrease in insulin-mediated inhibition of lipolysis, whereas hepatic insulin sensitivity improved with the NVP/LPV/r regimen.

Multifactorial intervention to reduce falls in older people at high risk of recurrent falls: a randomized controlled trial.

BACKGROUND: Falls occur frequently in older people and strongly affect quality of life. Guidelines recommend multifactorial, targeted fall prevention. We evaluated the effectiveness of a multifactorial intervention in older persons with a high risk of recurrent falls. METHODS: A randomized controlled trial was conducted from April 3, 2005, to July 21, 2008, at the geriatric outpatient clinic of a university hospital and regional general practices in the Netherlands. Of 2015 persons identified, 217 persons aged 65 years or older were selected to participate. They had a high risk of recurrent falls and no cognitive impairment and had visited the emergency department or their family physician after a fall. The geriatric assessment and intervention were aimed at reduction of fall risk factors. Primary outcome measures were time to first and second falls after randomization. Secondary outcome measures were fractures, activities of daily living, quality of life, and physical performance. RESULTS: Within 1 year, 55 (51.9%) of the 106 intervention participants and 62 (55.9%) of the 111 usual care (control) participants fell at least once. No significant treatment effect was demonstrated for the time to first fall (hazard ratio, 0.96; 95% confidence interval, 0.67-1.37) or the time to second fall (1.13; 0.71-1.80). Similar results were obtained for secondary outcome measures and for per-protocol analysis. One intervention participant died vs 7 in the control group (hazard ratio, 0.15; 95% confidence interval, 0.02-1.21). CONCLUSION: This multifactorial fall-prevention program does not reduce falls in high-risk, cognitively intact older persons. Trial Registration isrctn.org Identifier: ISRCTN11546541.

HIV monotherapy with ritonavir-boosted protease inhibitors: a systematic review.

OBJECTIVE: To assess the efficacy of ritonavir-boosted protease inhibitor monotherapy. DESIGN AND METHODS: Systematic review of all protease inhibitor-monotherapy studies published in peer-reviewed journals or presented at conferences to date. Data of randomized controlled trials were pooled to yield common odds ratios. RESULTS: Twenty-two protease inhibitor-monotherapy studies were identified. In the intent-to-treat analysis, 395 out of 582 (67.9%) patients had undetectable HIV-RNA at the end of follow-up. In the six randomized controlled trials (all lopinavir/ritonavir monotherapy), the risk of therapy failure was greater on monotherapy: 121 out of 364 (33.2%) patients on monotherapy against 64 out of 280 (22.9%) patients on HAART [pooled odds ratio 1.48 (95% confidence interval 1.02-2.13, P = 0.037)]. Regarding patients with successfully resuppressed HIV-RNA upon (re-)introducing nucleoside reverse transcriptase inhibitors (NRTIs) as nonfailures, the risk of therapy failure was comparable: 98 out of 364 (26.9%) against 64 out of 280 (22.9%) patients [odds ratio 1.05 (95% confidence interval 0.72-1.53, P = 0.81)]. CONCLUSION: The overall efficacy of ritonavir-boosted protease inhibitor monotherapy is inferior to HAART. The efficacy improves in patients started on monotherapy after suppressed HIV-RNA for at least 6 months. Ten percent of patients have viral rebound with HIV-RNA levels between 50 and 500 copies/ml. Possible explanations are lack of HIV suppression in particular cells or compartments, alternative resistance mechanisms, and nonadherence. Once proven that reintroduction of NRTIs, in patients with loss of viral suppression, is safe and effective, a broader use of simplification of HAART to protease inhibitor monotherapy might be justified. This review supports that the majority of patients with prolonged viral suppression on HAART can successfully be treated with protease inhibitor monotherapy. Arguments for this strategy are NRTI/NNRTI side effects, NRTI/NNRTI resistance, and costs.

Increase in carotid artery intima-media thickness and arterial stiffness but improvement in several markers of endothelial function after initiation of antiretroviral therapy.

BACKGROUND: The risk of cardiovascular disease in human immunodeficiency virus (HIV)-infected patients is an increasing concern. We studied the changes in vascular properties after the initiation of combination antiretroviral therapy (cART) as well as the contribution of different drug classes. METHODS: cART-naive men were randomized to receive either lopinavir/ritonavir (LPV/r) plus zidovudine/lamivudine (ZDV/3TC) (n = 19) or LPV/r plus nevirapine (NVP) (n = 18). Carotid artery intima-media thickness (C-IMT), arterial stiffness (distensibility coefficients [DCs] and compliance coefficients [CCs] of the carotid, femoral, and brachial arteries; carotid elastic modulus; and augmentation index), and markers of endothelial function (soluble vascular cell adhesion molecule [sVCAM]-1, intercellular adhesion molecule [sICAM]-1, plasma von Willebrand factor (vWF) antigen, and plasminogen activator inhibitor-1 antigen) and inflammation (high-sensitivity C-reactive protein) were measured before the initiation of cART and after 3, 12, and 24 months of cART. RESULTS: C-IMT increased by 0.061 +/- 0.016 mm (P < .001) in the ZDV/3TC/LPV/r arm and by 0.044 +/- 0.018 mm (P = .012) in the NVP/LPV/r arm (data are estimated means +/- SEs). Femoral artery DC (-1.66 +/- 0.78 x 10(-3)/kPa [P = .035]) and CC (-0.11 +/- 0.053 mm(2)/kPa [P = .43]) decreased in the ZDV/3TC/LPV/r arm and femoral DC decreased in the NVP/LPV/r arm (-1.72 +/- 0.85 x 10(-3)/kPa [P = .046]), with no significant difference in C-IMT or arterial stiffness between arms. sVCAM-1, sICAM-1, and vWF levels decreased significantly in both groups. CONCLUSION: C-IMT and femoral artery stiffness increased after the initiation of cART, whereas several markers of endothelial function improved, regardless of the composition of cART. Trial registration. ClinicalTrials.gov identifier: NCT00122226 .

Carotid intima-media thickness and arterial stiffness in HIV-infected patients: the role of HIV, antiretroviral therapy, and lipodystrophy.

OBJECTIVES: HIV-infected patients using combination antiretroviral therapy (ART) have an increased cardiovascular risk. We aimed to identify the effects of HIV, ART, and lipodystrophy (LD) on carotid artery intima-media thickness (C-IMT), a surrogate measure of atherosclerosis, and arterial stiffness, a marker of cardiovascular risk. DESIGN: Case-control study of 77 HIV-infected men (55 exposed to ART, 22 ART naive, and 23 with LD) and 52 controls. METHODS: C-IMT was measured ultrasonically, and arterial stiffness was estimated by distensibility (DC) and compliance (CC) coefficients of the carotid, femoral, and brachial arteries, by the carotid Young elastic modulus and pulse wave velocity. RESULTS: After adjustment for cardiovascular risk factors, HIV-infected patients had a 0.067 mm (10.8%) greater C-IMT than controls, 13.6% and 29.5% lower DC, and 14.1% and 31% lower CC of the carotid and femoral arteries, respectively, but similar Young elastic modulus and pulse wave velocity. Patients exposed to ART had similar C-IMT compared with ART-naive patients but 25.9% lower DC and 21.7% lower CC of the femoral artery. Arterial properties did not differ between patients with and without LD. CONCLUSIONS: HIV infection is independently associated with C-IMT and generally increased arterial stiffness. ART use is associated with increased stiffness of the femoral artery.

First line zidovudine/lamivudine/lopinavir/ritonavir leads to greater bone loss compared to nevirapine/lopinavir/ritonavir.

OBJECTIVE: We studied changes in bone mineral density (BMD) and bone turnover after initiation of combination antiretroviral therapy (cART) and the contribution of zidovudine/lamivudine (ZDV/3TC) in particular. DESIGN: Randomized clinical trial comparing lopinavir/ritonavir(LPV/r) + ZDV/3TC with LPV/r + nevirapine (NVP) in 50 cART-naive men. METHODS: Dual energy X-ray absorptiometry (DXA) and quantitative computed tomography scans (QCT) were performed at baseline and 3, 12, and 24 months after cART initiation. Serum 25-hydroxy-vitamin D3, parathyroid hormone (PTH), osteocalcin, and urine deoxypyridinoline (DPD)/creatinine ratio were measured. RESULTS: BMD decreased rapidly in both femoral neck and lumbar spine after cART initiation. BMD loss during 24 months measured by DXA, but not by QCT, was greater in the ZDV/3TC/LPV/r group compared to the NVP/LPV/r group [femoral neck: -6.3% +/- 1.0% (P < 0.0001) compared to -2.3% +/- 0.9% (P = 0.01), between-group P = 0.0006); lumbar spine: -5.1% +/- 0.8% (P < 0.0001) compared to -2.6% +/- 0.7% (P = 0.0006), between-group P = 0.07]. Osteocalcin [+1.60 +/- 0.32 (P < 0.0001) and +1.81 +/- 0.29 (P < 0.0001) nmol/l] and the urine DPD/creatinine ratio [+1.35 +/- 0.44 (P = 0.0029) and +1.19 +/- 0.38 nmol/mmol (P = 0.0024)] increased in both groups over 24 months, with no significant difference between groups. PTH increased to a greater degree in the NVP/LPV/r group [+2.0 +/- 0.31 pmol/l (P < 0.0001)] compared to [+0.81 +/- 0.33 pmol/l (P = 0.021) in the ZDV/3TC/LPV/r group]. CONCLUSION: BMD in both femoral neck and lumbar spine decreased rapidly after initiation of cART, in parallel to an increase in bone turnover. The greater bone loss in the ZDV/3TC/LPV/r group compared to the NVP/LPV/r group suggests that ZDV/3TC contributes to this process. The PTH increase does not explain this greater bone loss.

Zidovudine/lamivudine for HIV-1 infection contributes to limb fat loss.

BACKGROUND: Lipoatrophy is known to be associated with stavudine as part of the treatment for HIV infection, but it is less clear if this serious side effect is also related to other nucleoside reverse transcriptase inhibitors like zidovudine. We aimed to determine whether zidovudine-sparing first-line antiretroviral therapy would lead to less lipoatrophy and other metabolic changes than zidovudine-containing therapy. METHODOLOGY/PRINCIPAL FINDINGS: Fifty antiretroviral therapy-naïve HIV-1 infected men with an indication to start antiretroviral therapy were included in a randomized single blinded clinical trial. Randomisation was between zidovudine-containing therapy (zidovudine/lamivudine+lopinavir/ritonavir) and zidovudine-sparing therapy (nevirapine+lopinavir/ritonavir). Main outcome measures were body composition assessed by computed tomography and dual-energy X-ray absorptiometry scan and lipid profile before and after 3, 12, 24 months of antiretroviral therapy. In the zidovudine/lamivudine+lopinavir/ritonavir group, from 3 months onward limb fat decreased progressively by 684+/-293 grams (estimated mean+/-standard error of the mean)(p = 0.02) up to 24 months whereas abdominal fat increased, but exclusively in the visceral compartment (+21.9+/-8.1 cm(2), p = 0.008)). In contrast, in the nevirapine+lopinavir/ritonavir group, a generalized increase in fat mass was observed. After 24 months no significant differences in high density lipoprotein and total/high density lipoprotein cholesterol ratio were found between both treatment groups, but total and low density lipoprotein cholesterol levels were higher in the nevirapine+lopinavir/ritonavir group (6.1+/-0.2 versus 5.3+/-0.2 and 3.6+/-0.1 versus 2.8+/-0.1 mmol/l respectively, p<0.05). Virologic response and safety were comparable in both groups. CONCLUSIONS/SIGNIFICANCE: Zidovudine/lamivudine+lopinavir/ritonavir, but not nevirapine+lopinavir/ritonavir in antiretroviral therapy-naïve patients, is associated with lipoatrophy and greater relative intraabdominal lipohypertrophy, suggesting that zidovudine/lamivudine contributes to both these features of lipodystrophy. These findings support to no longer consider zidovudine/lamivudine as one of the preferred possible components of first-line antiretroviral therapy where alternative treatments are available. TRIAL REGISTRATION: ClinicalTrials.gov NCT 00122226.

Zidovudine/lamivudine contributes to insulin resistance within 3 months of starting combination antiretroviral therapy.

BACKGROUND: Patients with antiretroviral therapy (ART)-associated lipodystrophy frequently have disturbances in glucose metabolism associated with insulin resistance. It is not known whether changes in body composition are necessary for the development of these disturbances in ART-naive patients starting treatment with different combination ART regimens. METHODS: Glucose metabolism and body composition were assessed before and after 3 months of ART in a prospective randomized clinical trial of HIV-1-positive ART-naive men taking lopinavir/ritonavir within either a nucleoside reverse transcriptase inhibitor (NRTI)-containing regimen (zidovudine/lamivudine; n = 11) or a NRTI-sparing regimen (nevirapine; n = 9). Glucose disposal, glucose production and lipolysis were measured after an overnight fast and during a hyperinsulinaemic-euglycaemic clamp using stable isotopes. Body composition was assessed by computed tomography and dual-energy X-ray absorptiometry. RESULTS: In the NRTI-containing group, body composition did not change significantly in 3 months; insulin-mediated glucose disposal decreased significantly (25%; P < 0.001); and fasting glycerol turnover increased (22%; P < 0.005). Hyperinsulinaemia suppressed glycerol turnover equally before and after treatment. The disturbances in glucose metabolism were not accompanied by changes in adiponectin or other glucoregulatory hormones. In contrast, glucose metabolism did not change in the NRTI-sparing arm. Glucose disposal significantly differed over time between the arms (P < 0.01). CONCLUSIONS: Treatment for 3 months with a NRTI-containing, but not a NRTI-sparing, regimen resulted in a 25% decrease in insulin-mediated glucose disposal and a 22% increase in fasting lipolysis. In the absence of discernable changes in body composition, NRTI may directly affect glucose metabolism, the mechanism by which remains to be elucidated.

Quantitative detection of Staphylococcus aureus and Enterococcus faecalis DNA in blood to diagnose bacteremia in patients in the intensive care unit.

Direct detection of bacterial DNA in blood offers a fast alternative to blood culture and is presumably unaffected by the prior use of antibiotics. We evaluated the performance of two real-time PCR assays for the quantitative detection of Staphylococcus aureus bacteremia and for Enterococcus faecalis bacteremia directly in blood samples, without prior cultivation. Whole-blood samples for PCR were obtained simultaneously with blood cultures from patients admitted to the intensive care unit of our hospital. After the extraction of DNA from 200 mul of blood, real-time PCR was performed for the specific detection and quantification of S. aureus and E. faecalis DNA. The sensitivity for bacteremia of the S. aureus PCR was 75% and that of the E. faecalis PCR was 73%, and both tests had high specificity values (93 and 96%, respectively). PCR amplification reactions were positive for S. aureus for 10 (7%) blood samples with negative blood cultures, and 7 (4%) PCR reactions were positive for E. faecalis. The majority of these PCR results were likely (50%) or possibly (42%) related to infection with the specific microorganism, based on clinical data and radiological and microbiological investigations. PCR results were concordant for 95% of paired whole-blood samples, and blood culture results were concordant for 97% of the paired samples. We conclude that the detection of S. aureus and E. faecalis DNA in blood by real-time PCR enables a rapid diagnosis of bacteremia and that a positive DNAemia is related to proven or possible infection with the specific microorganism in the majority of patients with negative blood cultures.

Faster identification of pathogens in positive blood cultures by fluorescence in situ hybridization in routine practice.

Rapid identification of microorganisms in blood cultures is required to optimize empirical treatment at an early stage. Fluorescence in situ hybridization (FISH) can reduce the time to identification of microorganisms in growth-positive blood cultures. In this study, we evaluated the performance, time to identification, and potential clinical benefits of FISH compared to those of conventional culture methods in routine practice. After Gram staining, blood culture fluids were simultaneously further identified with FISH and with conventional culture methods. Results and points in time of FISH and culture identification (provisional and final identifications) were collected and compared. For 91% of microorganisms, the genus or family name was identified, and for 79%, the species name could be attributed. The sensitivity and specificity of the individual probes exceeded 95%, except for the Enterobacteriaceae probe (sensitivity, 89%). Cross-hybridization was obtained with the Klebsiella pneumoniae probe for Klebsiella oxytoca. The time gains of FISH and final culture identification were more than 18 h for bacteria and 42 h for yeasts. With FISH, Staphylococcus aureus was differentiated from coagulase-negative staphylococci 1.4 h faster than by provisional identification (P < 0.001). In conclusion, FISH allows rapid and reliable identification of the majority of microorganisms in growth-positive blood cultures. The substantial time gain of identification with FISH may allow same-day adjustment of antimicrobial therapy, and FISH is especially useful if no provisional identification is obtained. With further extension of the number of probes and a reduction in turnaround time, FISH will become a very useful diagnostic tool in the diagnosis of bloodstream infections.