Higher-than-expected rates of lactic acidosis among highly active antiretroviral therapy-treated women in Botswana: preliminary results from a large randomized clinical trial

Emerging Roles of m7G-Cap Hypermethylation and Nuclear Cap-Binding Proteins in Bypassing Suppression of eIF4E-Dependent Translation

Translation regulation is essential to the survival of hosts. Most translation initiation falls under the control of the mTOR pathway, which regulates protein production from mono-methyl-guanosine (m7G) cap mRNAs. However, mTOR does not regulate all translation; hosts and viruses alike employ alternative pathways, protein factors, and internal ribosome entry sites to bypass mTOR. Trimethylguanosine (TMG)-caps arise from hypermethylation of pre-existing m7G-caps by the enzyme TGS1 and are modifications known for snoRNA, snRNA, and telomerase RNA. New findings originating from HIV-1 research reveal that TMG-caps are present on mRNA and license translation via an mTOR-independent pathway. Research has identified TMG-capping of selenoprotein mRNAs, junD, TGS1, DHX9, and retroviral transcripts. TMG-mediated translation may be a missing piece for understanding protein synthesis in cells with little mTOR activity, including HIV-infected resting T cells and nonproliferating cancer cells. Viruses display a nuanced interface with mTOR and have developed strategies that take advantage of the delicate interplay between these translation pathways. This review covers the current knowledge of the TMG-translation pathway. We discuss the intimate relationship between metabolism and translation and explore how this is exploited by HIV-1 in the context of CD4+ T cells. We postulate that co-opting both translation pathways provides a winning strategy for HIV-1 to dictate the sequential synthesis of its proteins and balance viral production with host cell survival.

Oxidative phosphorylation in HIV-1 infection: impacts on cellular metabolism and immune function

Human Immunodeficiency Virus Type 1 (HIV-1) presents significant challenges to the immune system, predominantly characterized by CD4+ T cell depletion, leading to Acquired Immunodeficiency Syndrome (AIDS). Antiretroviral therapy (ART) effectively suppresses the viral load in people with HIV (PWH), leading to a state of chronic infection that is associated with inflammation. This review explores the complex relationship between oxidative phosphorylation, a crucial metabolic pathway for cellular energy production, and HIV-1, emphasizing the dual impact of HIV-1 infection and the metabolic and mitochondrial effects of ART. The review highlights how HIV-1 infection disrupts oxidative phosphorylation, promoting glycolysis and fatty acid synthesis to facilitate viral replication. ART can exacerbate metabolic dysregulation despite controlling viral replication, impacting mitochondrial DNA synthesis and enhancing reactive oxygen species production. These effects collectively contribute to significant changes in oxidative phosphorylation, influencing immune cell metabolism and function. Adenosine triphosphate (ATP) generated through oxidative phosphorylation can influence the metabolic landscape of infected cells through ATP-detected purinergic signaling and contributes to immunometabolic dysfunction. Future research should focus on identifying specific targets within this pathway and exploring the role of purinergic signaling in HIV-1 pathogenesis to enhance HIV-1 treatment modalities, addressing both viral infection and its metabolic consequences.

Conditional expression of HIV-1 tat in the mouse alters the onset and progression of tonic, inflammatory and neuropathic hypersensitivity in a sex-dependent manner

BACKGROUND

At least one-third of HIV-1-afflicted individuals experience peripheral neuropathy. Although the underlying mechanisms are not known, they may involve neurotoxic HIV-1 proteins.

METHODS

We assessed the influence of the neurotoxic HIV-1 regulatory protein, Tat, on inflammatory and neuropathic nociceptive behaviours using transgenic male and female mice that conditionally expressed (or did not express) HIV-1 Tat1-86 in fibrillary acidic protein-expressing glia in the central and peripheral nervous systems.

RESULTS

Tat induction significantly attenuated the time spent paw-licking following formalin injection (2.5%, i.pl.) in both male and female mice. However, significant sex differences were observed in the onset and magnitude of inflammation and sensory sensitivity following complete Freund's adjuvant (CFA) injection (10%, i.pl.) after Tat activation. Unlike female mice, male mice showed a significant attenuation of paw swelling and an absence of mechanical/thermal hypersensitivity in response to CFA after Tat induction. Male Tat(+) mice also showed accelerated recovery from chronic constrictive nerve injury (CCI)-induced neuropathic mechanical and thermal hypersensitivity compared to female Tat(+) mice. Morphine (3.2 mg/kg) fully reversed CCI-induced mechanical hypersensitivity in female Tat(-) mice, but not in Tat(+) females.

CONCLUSIONS

The ability of Tat to decrease oedema, paw swelling, and limit allodynia suggests a sequel of events in which Tat-induced functional deficits precede the onset of mechanical hypersensitivity. Moreover, HIV-1 Tat attenuated responses to inflammatory and neuropathic insults in a sex-dependent manner. HIV-1 Tat appears to directly contribute to HIV sensory neuropathy and reveals sex differences in HIV responsiveness and/or the underlying peripheral neuroinflammatory and nociceptive mechanisms.

Predictors of HIV virological failure and drug resistance in Chinese patients after 48 months of antiretroviral treatment, 2008-2012: a prospective cohort study

OBJECTIVE

To explore factors associated with HIV virological failure (VF) and HIV drug resistance (HIVDR) among HIV-positive Chinese individuals 4 years after initiating first-line lamivudine-based antiretroviral treatment (ART) in 2008 at five sentinel sites.

DESIGN

First-line ART initiators who were previously treatment naïve were selected using consecutive ID numbers from the 2008 National Surveillance Database into a prospective cohort study. Questionnaires and blood samples were collected in 2011 and 2012 to assess the outcomes of interest: VF (defined as viral load ≥1000 copies/mL) and HIVDR (defined as VF with genetic drug-resistant mutations). Questionnaires and data from National Surveillance Database assessed demographics and drug adherence data.

RESULTS

536 individuals with HIV were analysed; the 4-year risk of VF was 63 (11.8%) and HIVDR was 27 (5.0%). Female participants initiating stavudine (D4T)-based regimens were more susceptible to both VF (adjusted OR (aOR)=2.5, 95% CI 1 to 6.1, p=0.04) and HIVDR (aOR=3.6, 95% CI 1 to 12.6, p=0.05) versus zidovudine-based regimens. Male participants missing doses in past month were more susceptible to both VF (aOR=2.8, 95% CI 1.1 to 7, p=0.03) and HIVDR (aOR=9.7, 95% CI 2.1 to 44.1, p<0.01). Participants of non-Han nationality were of increased risk for HIVDR (aOR from 4.8 to 12.2, p<0.05) and non-Han men were at increased risk for VF (aOR=2.9, 95% CI 1.1 to 7.3, p=0.02). All 27 participants detected with HIVDR had non-nucleoside reverse-transcriptase inhibitor mutations, 21 (77.8%) also had nucleoside reverse-transcriptase inhibitor mutations, and no protease inhibitor mutations were detected.

CONCLUSIONS

Our findings suggest successful treatment outcomes at 4 years for roughly 90% of patients. We suggest conducting further study on whether and when to change ART regimen for women initiated with D4T-based regimen, and reinforcing adherence counselling for men. Increased VF and HIVDR risk among non-Han minorities warrants further exploration, and ethnic minorities may be an important group to tailor adherence-focused interventions.

Role of nonalcoholic fatty liver disease as risk factor for drug-induced hepatotoxicity

BACKGROUND

Obesity is often associated with nonalcoholic fatty liver disease (NAFLD), which refers to a large spectrum of hepatic lesions including fatty liver, nonalcoholic steatohepatitis (NASH) and cirrhosis. Different investigations showed or suggested that obesity and NAFLD are able to increase the risk of hepatotoxicity of different drugs. Some of these drugs could induce more frequently an acute hepatitis in obese individuals whereas others could worsen pre-existing NAFLD.

AIM

The main objective of the present review was to collect the available information regarding the role of NAFLD as risk factor for drug-induced hepatotoxicity. For this purpose, we performed a data-mining analysis using different queries including drug-induced liver injury (or DILI), drug-induced hepatotoxicity, fatty liver, nonalcoholic fatty liver disease (or NAFLD), steatosis and obesity. The main data from the collected articles are reported in this review and when available, some pathophysiological hypotheses are put forward.

RELEVANCE FOR PATIENTS

Drugs that could pose a potential risk in obese patients include compounds belonging to different pharmacological classes such as acetaminophen, halothane, methotrexate, rosiglitazone, stavudine and tamoxifen. For some of these drugs, experimental investigations in obese rodents confirmed the clinical observations and unveiled different pathophysiological mechanisms which could explain why these pharmaceuticals are particularly hepatotoxic in obesity and NAFLD. Other drugs such as pentoxifylline, phenobarbital and omeprazole might also pose a risk but more investigations are required to determine whether this risk is significant or not. Because obese people often take several drugs for the treatment of different obesity-related diseases such as type 2 diabetes, hyperlipidemia and coronary heart disease, it is urgent to identify the main pharmaceuticals that can cause acute hepatitis on a fatty liver background or induce NAFLD worsening.

Magnitude of adverse drug reaction and associated factors among HIV-infected adults on antiretroviral therapy in Hiwot Fana specialized university hospital, eastern Ethiopia

INTRODUCTION

Human immunodefiecency virus infected patients did not adhere correctly to their Antiretroviral Therapy because of the drugs adverse effects. Thus, continuous evaluation of the adverse effect of Antiretroviral Therapy will help to make more effective treatment. The aim of this study was to assess the prevalence of Adverse Drug Reaction and associated factors on Antiretroviral Therapy among Human immunodefiecency virus infected Adults at Hiwot Fana Specialized University Hospital, Eastern Ethiopia.

METHODS

A Hospital based retrospective study was conducted among 358 of adult patients clinical records on antiretroviral Therapy from April1 to June30, 2014.

RESULTS

The overall prevalence of Adverse Drug Reaction among Human immunodefiecency virus infected patients on antiretroviral Therapy was 17.0%. Of reported Adverse Drug Reaction, 80.3%, 18% and 1.7% occurred in patients on Stavudine, Zidovudine and Tenofovir based regimens respectively. The common Adverse Drug Reaction were lipodystrophy (fat change) (49.2%), numbness/tingling (27.9%), peripheral neuropathy (18%) and (8.2%) anaemia (8.2%). Patients on Stavudine containing regimens were more likely to develop Adverse Drug Reaction compared to Zidovudine (AOR = 0.212, 95% CI 0.167, 0.914, p<0.001) and Tenofovir (AOR=0.451, 95% CI 0.532, 0.948, p<0.001).

CONCLUSION

The overall prevalence of Adverse Drug Reaction among Human immunodefiecency virus infected patients in this study was 17% and more common on those patients taking Stavudine based regimen. Lipodystrophy and peripheral neuropathy were significantly associated with stavudine-based regimens, while anaemia was significantly associated with zidovudine based regimens. Thus regular clinical and laboratory monitoring of patients on Antiretroviral Therapy should be strengthened.

Drugs influencing acid base balance and bicarbonate concentration readings

Serum bicarbonate dosage is sensitive to pharmacological interferences. However, elevated bicarbonate concentration reflects chronic hypoventilation and has been proposed as a simple marker for screening patients with Obesity Hypoventilation Syndrome (OHS), a currently underdiagnosed multimorbid and high mortality disease. We provide a practical overview of the different drugs acting on the acid-base equilibrium to aid clinicians to interpret bicarbonate concentration readings. Little is known about the chronic impact of the usual doses of these drugs on serum bicarbonate concentration and further studies are needed. It is essential to take into account drugs that could interfere with this parameter to avoid misinterpretation of serum bicarbonate levels.

Pharmacogenomics of antimicrobial agents

Antimicrobial efficacy and toxicity varies between individuals owing to multiple factors. Genetic variants that affect drug-metabolizing enzymes may influence antimicrobial pharmacokinetics and pharmacodynamics, thereby determining efficacy and/or toxicity. In addition, many severe immune-mediated reactions have been associated with HLA class I and class II genes. In the last two decades, understanding of pharmacogenomic factors that influence antimicrobial efficacy and toxicity has rapidly evolved, leading to translational success such as the routine use of HLA-B*57:01 screening to prevent abacavir hypersensitivity reactions. This article examines recent advances in the field of antimicrobial pharmacogenomics that potentially affect treatment efficacy and toxicity, and challenges that exist between pharmacogenomic discovery and translation into clinical use.

Adverse Drug Reactions in HIV/AIDS Patients at a Tertiary Care Hospital in Penang, Malaysia

In the current study we explored the occurrence of adverse drug reactions (ADRs) to antiretroviral therapy among human immune-deficiency virus (HIV)/AIDS patients. We concluded an observational retrospective study in all patients who were diagnosed with HIV infection and were receiving highly active antiviral therapy from Jan. 2007 to Dec. 2012 at Hospital Pulau Pinang, Malaysia. Patient socio-demographic details along with clinical features and susceptible ADRs were observed during the study period. Out of 743 patients, 571 (76.9%) were men, and 172 (23.1%) were women. Overall 314 (42.2%) patients experienced ADRs. A total of 425 ADRs were reported, with 311 (73.1%) occurring in men and 114 (26.8%) in women, with a significant statistical relationship (P value (P) = 0.02, OR = 1.21). Overall 239 (56.2%) ADRs were recorded among Chinese, 94 (22.1%) in Malay, and 71 (16.7%) in Indian patients, which had a statistically significant association with ADRs (P = 0.05, OR = 1.50). Out of a total 425 among ADRs, lipodystrophy was recorded in 151 (35.5%) followed by skin rashes in 80 (18.8%), anemia in 74 (17.4%), and peripheral neuropathy in 27 (6.3%) patients. These findings suggest a need of intensive monitoring of ADRs in HIV treatment centres across Malaysia.

Hyperlactatemia in a group of HIV patients living in Yaounde-Cameroon

Background and aim

Prolonged exposure to highly active antiretroviral therapy (HAART) is associated with adverse effects such as hyperlactatemia. We determined the prevalence and risk factors for developing hyperlactatemia among human immunodeficiency virus (HIV)-infected cameroonians on antiretroviral therapy (ART).

Methods

We conducted a cross-sectional study from January to April 2012 involving 91 HIV-infected patients receiving ART for at least 12 months and 30 HIV-infected patients who have never received ART (ART-naïve patients). Plasma lactate levels were determined after at least 12 hours of overnight fasting and hyperlactatemia defined as lactate concentrations ≥ 3 mmol/L. The prevalence of hyperlactatemia was determined and the risk factors were analyzed by a multivariate logistic regression model.

Results

The mean lactataemia was significantly higher in the group of HIV patients currently taking ART than in the ART-naïve one (2.3 ± 1.3 and 1.7 ± 0.7 mmol/L respectively, p = 0.002). Patients on first line ART regimens had significantly higher lactatemia than those on second line regimens (2.5 ± 1.5 and 1.9 ± 0.7 mmol/L respectively, p = 0.014). The prevalence of hyperlactatemia in HIV patients receiving ART and in ART-naïve HIV patients was respectively 18.7 and 6.7% (p = 0.095). ART-exposure (adjusted odds ratio (aOR) 5.44, 95% confidence interval (CI) 1.06 – 27.84; p = 0.042) and being on a first line regimen (aOR 16.22, 95% CI 1.57 – 167.91; p = 0.019) were independent strong predictors of hyperlactatemia.

Conclusion

Hyperlactatemia was not rare in our study population. Being on a first line regimen constitutes an important risk factor for developing hyperlactatemia. Measurement of plasma lactate may be useful in optimizing the management of HIV-positive persons on ART.

Short communication: Aging not gender is associated with high atazanavir plasma concentrations in Asian HIV-infected patients

Physiological effects of aging make the older population more susceptible to adverse drug events and drug-drug interactions. We evaluated the impact of aging and gender on the pharmacokinetics (PK) of atazanavir/ritonavir (ATV/r) 300/100 mg once daily (qd) in 22 well-suppressed HIV-infected patients. This was a 24-h intensive PK study. Subjects were HIV-1-infected adults aged ≥18 years with HIV RNA <50 copies/ml and treated with ATV/r 300/100 mg once daily plus two nucleoside reverse transcriptase inhibitors (NRTIs) for at least 2 weeks. Atazanavir and ritonavir plasma concentrations were measured by validated high-performance liquid chromatography (HPLC). Plasma PK parameters were calculated using noncompartmental methods. Since 50% of the patients were older than 42 years, age 42 was selected as the cut-off point for the older (>42 years) group. Gender, weight, duration of ATV/r therapy, and proportion treated with tenofovir disoproxil fumarate (TDF)-containing regimens did not differ between both groups. Patients from the aging group had a reduced creatinine clearance (91 versus 76 ml/min). The older group had a higher atazanavir exposure with median AUC(0-24) 71.2 vs. 53.1 mg·h/liter, C(max) 8.5 vs. 5.5 mg/liter, and C(trough) 1.17 vs. 0.78 mg/liter, and slower apparent clearance (3.5 vs. 4.8 liter/h). Ten patients (91%) from the older group and 36% from the younger group had ATV C(trough) levels higher than the proposed upper limit for toxicity of 0.85 mg/liter. Females had a lower body weight (BW) (46 versus 63 kg) than the males, but atazanavir concentrations in females were greater. However, in multivariate analysis, older age was the only significant predictor for higher atazanavir concentrations. Parameter estimate for age and atazanavir AUC after adjusting for gender and BW was 2.17 (95% CI 1.01-3.33). That is, for every year increase in age, AUC increases by approximately 2 mg·h/liter. Age seems to be an important factor influencing atazanavir pharmacokinetics. Patients from the aging group appeared to have higher atazanavir exposure compared to the younger group. Further PK explorations of ATV in the extremely aged population are warranted.

Patients with immunodeficiency

Patients presenting in an immunocompromised state merit special consideration when being evaluated for fitness to undergo surgery. A variety of immunodeficient conditions and their respective therapies, including human immunodeficiency virus, cancer, and transplantation, exert numerous systemic effects that may lead to multiorgan dysfunction. Understanding the potential impact of these disease manifestations, and their proper evaluation, is essential in achieving optimal perioperative outcomes for these patients.

Longitudinal lactate levels from routine point-of-care monitoring in adult Malawian antiretroviral therapy patients: associations with stavudine toxicities

Introduction

Stavudine is still widely used in under-resourced settings such as Malawi due to its low price. It frequently causes peripheral neuropathy and lipodystrophy and increases the risk of lactic acidosis and other high lactate syndromes.

Methods

We studied the association of longitudinal lactate levels, obtained by routine, 3-monthly point-of-care monitoring, with peripheral neuropathy, lipodystrophy and high lactate syndromes in adult Malawians who were in the second year of stavudine containing antiretroviral therapy (ART).

Results

Point-of-care lactate measurements were feasible in a busy urban ART clinic. Of 1170 lactate levels collected from 253 patients over the course of one year, 487 (41.8%) were elevated (>2.2mg/dl), 58 (5.0%) were highly elevated (>3.5mg/dl). At least one elevated lactate level occurred in 210 (83.0%) of patients and sustained hyperlactatemia in 65 (26.4%). In random effects analyses lipodystrophy and peripheral neuropathy were associated with higher lactate levels. Only five patients developed high lactate syndromes (one lactic acidosis) of whom no preceding lactate measurements were available because events had started before enrolment. Lactate levels significantly decreased over time and no high lactate syndromes were observed after the 15th month on ART.

Conclusion

Lipodystrophy and peripheral neuropathy were associated with higher lactate levels. Lactate levels decreased over time, coinciding with absence of new high lactate syndromes after the 15th month on ART.

Mitochondrial toxicity studied with the PBMC of children from the Chinese national pediatric highly active antiretroviral therapy cohort

As the backbone of highly active antiretroviral therapy (HAART), nucleoside reverse transcriptase inhibitors (NRTIs) have effectively improved outcomes for HIV-infected patients. However, long-term treatment with NRTIs can cause a series of pathologies associated with mitochondrial toxicity. To date, the status and mechanism of mitochondrial toxicity induced by NRTIs are still not clear, especially in HIV-infected children. As part of the national pediatric HAART program in China, our study focused on mitochondrial toxicity and its potential mechanism in HIV-1-infected children who were divided into two groups based on their duration of treatment with NRTIs: one group received treatment for less than 36 months and one group was treated for 36 to 72 months. The control group comprised age-matched non-HIV-infected children. Blood lactic acid and ATP levels in peripheral blood mononuclear cells (PBMCs) were measured to evaluate mitochondrial function, and mtDNA copies and mutations in PBMCs were determined for detecting mtDNA lesions. Simultaneously, TK2 and P53R2 gene expression in PBMC was measured. As compared with the control group, blood lactic acid levels in both NRTI treatment groups were significantly higher, whereas ATP levels and mtDNA mutation rates in PBMCs did not differ between the control and the two NRTI treatment groups. Both NRTI treatment groups exhibited significant mtDNA loss. N Moreover, we found that P53R2 mRNA expression and protein levels were significantly reduced in both treatment groups and that TK2 mRNA expression and protein levels were induced in the long-term NRTI treatment group. These results suggest that mitochondrial toxicity occurs in long-term HAART patients and that P53R2 and TK2 levels in PBMCs are useful biomarkers for detecting mitochondrial toxicity in patients on long-term treatment with NRTIs.

Antiretroviral therapy, labor productivity, and sex: a longitudinal cohort study of tea pluckers in Kenya

OBJECTIVE

To estimate the impact of antiretroviral therapy (ART) on labor productivity and income using detailed employment data from two large tea plantations in western Kenya for HIV-infected tea pluckers who initiated ART.

DESIGN

Longitudinal study using primary data on key employment outcomes for a group of HIV-infected workers receiving antiretroviral therapy (ART) and workers in the general workforce.

METHODS

We used nearest-neighbor matching methods to estimate the impacts of HIV/AIDS and ART among 237 HIV-positive pluckers on ART (index group) over a 4-year period (2 years pre-ART and post-ART) on 4 monthly employment outcomes - days plucking tea, total kilograms (kgs) harvested, total days working, and total labor income. Outcomes for the index group were compared with those for a matched reference group from the general workforce.

RESULTS

We observed a rapid deterioration in all four outcomes for HIV-infected individuals in the period before ART initiation and then a rapid improvement after treatment initiation. By 18-24 months after treatment initiation, the index group harvested 8% (men) and 19% (women) less tea than reference individuals. The index group earned 6% (men) and 9% (women) less income from labor than reference individuals. Women's income would have dropped further if they had not been able to offset their decline in tea plucking by spending more time on nonplucking assignments.

CONCLUSION

HIV-infected workers experienced long-term income reductions before and after initiating ART. The implications of such long-term impacts in low-income countries have not been adequately addressed.

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.

Causes of death on antiretroviral therapy: a post-mortem study from South Africa

Background

Mortality in the first months of antiretroviral therapy (ART) is a significant clinical problem in sub-Saharan Africa. To date, no post-mortem study has investigated the causes of mortality in these patients.

Methods

HIV-positive adults who died as in-patients at a Johannesburg academic hospital underwent chart-review and ultrasound-guided needle autopsy for histological and microbiological examination of lung, liver, spleen, kidney, bone marrow, lymph node, skin and cerebrospinal fluid. A clinico-pathologic committee considered all available data and adjudicated immediate and contributing causes of death.

Results

Thirty-nine adults were enrolled: 14 pre-ART, 15 early-ART (7–90 days), and 10 late-ART (>90 days). Needle sampling yielded adequate specimen in 100% of kidney, skin, heart and cerebrospinal fluid samples, 97% of livers and lungs, 92% of bone marrows, 87% of spleens and 68% of lymph nodes. Mycobacterial infections were implicated in 69% of deaths (26 of 27 of these due to M. tuberculosis), bacterial infections in 33%, fungal infections in 21%, neoplasm in 26%, and non-infectious organ failure in 26%. Immune reconstitution inflammatory syndrome (IRIS) was implicated in 73% of early-ART deaths. Post-mortem investigations revealed previously undiagnosed causes of death in 49% of cases. Multiple pathologies were common with 62% of subjects with mycobacterial infection also having at least one other infectious or neoplastic cause of death.

Conclusions

Needle biopsy was efficient and yielded excellent pathology. The large majority of deaths in all three groups were caused by M. tuberculosis suggesting an urgent need for improved diagnosis and expedited treatment prior to and throughout the course of antiretroviral therapy. Complex, unrecognized co-morbidities pose an additional challenge.

Risk factors for symptomatic hyperlactatemia and lactic acidosis among combination antiretroviral therapy-treated adults in Botswana: results from a clinical trial

Nucleoside analogue reverse transcriptase inhibitors are an integral component of combination antiretroviral treatment regimens. However, their ability to inhibit polymerase-γ has been associated with several mitochondrial toxicities, including potentially life-threatening lactic acidosis. A total of 650 antiretroviral-naive adults (69% female) initiated combination antiretroviral therapy (cART) and were intensively screened for toxicities including lactic acidosis as part of a 3-year clinical trial in Botswana. Patients were categorized as no lactic acidosis symptoms, minor symptoms but lactate <4.4 mmol/liter, and symptoms with lactate ≥ 4.4 mmol/liter [moderate to severe symptomatic hyperlactatemia (SH) or lactic acidosis (LA)]. Of 650 participants 111 (17.1%) developed symptoms and/or laboratory results suggestive of lactic acidosis and had a serum lactate drawn; 97 (87.4%) of these were female. There were 20 events, 13 having SH and 7 with LA; all 20 (100%) were female (p<0.001). Cox proportional hazard analysis limited to the 451 females revealed that having a higher baseline BMI was predictive for the development of SH/LA [aHR=1.17 per one-unit increase (1.08-1.25), p<0.0001]. Ordered logistic regression performed among all 650 patients revealed that having a lower baseline hemoglobin [aOR=1.28 per one-unit decrease (1.1-1.49), p=0.002] and being randomized to d4T/3TC-based cART [aOR=1.76 relative to ZDV/3TC (1.03-3.01), p=0.04] were predictive of the symptoms and/or the development of SH/LA. cART-treated women in sub-Saharan Africa, especially those having higher body mass indices, should receive additional monitoring for SH/LA. Women presently receiving d4T/3TC-based cART in such settings also warrant more intensive monitoring.

Effect of HIV-1 infection and sex on the cellular pharmacology of the antiretroviral drugs zidovudine and lamivudine

The cellular pharmacology of zidovudine (ZDV) and lamivudine (3TC) in vivo is not completely understood. This prospective longitudinal study investigated the relationship between HIV-1 serostatus, sex, race, and time on therapy with intracellular and plasma ZDV and 3TC concentrations. Of 20 HIV-seronegative and 23 HIV-seropositive volunteers enrolled, 16 (8 women) and 21 (5 women) completed all 12 study days, respectively. Volunteers began ZDV-3TC therapy (plus a third active drug in HIV-seropositive volunteers), and steady-state concentrations (C(ss)) were determined after days 1, 3, 7, and 12. A repeated-measures mixed model was utilized. HIV-seronegative status was associated with 22% (95% confidence interval [CI], 0%, 50%) and 37% (15%, 67%) higher C(ss) estimates compared to those of HIV-seropositive individuals for intracellular ZDV-TP and 3TC-TP levels, respectively. African-Americans had 36% (8%, 72%) higher ZDV-TP estimates than non-African-Americans. Sex was not associated with ZDV-TP or 3TC-TP (P > 0.19). Women had 36% (4%, 78%) higher plasma ZDV, but the effect was lessened when normalized by lean body weight (5% [-19%, 38%]; P = 0.68). Plasma 3TC was 19% (0%, 41%) higher in HIV-seropositive volunteers and 22% (0%, 48%) higher in African American volunteers, but these effects were not significant when corrected for creatinine clearance (7% [-9%, 20%] and -5% [-26%, 12%] for HIV serostatus and race, respectively; P > 0.35). These results suggest that HIV-seropositive status decreases and African American race elevates the cellular triphosphates of ZDV and 3TC. This information extends knowledge of ZDV and 3TC cellular pharmacology in vivo and provides new leads for future cellular pharmacology studies aimed at optimizing HIV prevention/treatment with these agents.

Increased incidence of symptomatic peripheral neuropathy among adults receiving stavudine- versus zidovudine-based antiretroviral regimens in Kenya

The incidence of peripheral neuropathy (PN) among adults initiating antiretroviral therapy (ART) containing stavudine (d4T) versus zidovudine (ZDV) is not well described. We compared 1-year incidence between d4T- and ZDV-based regimens in adults initiating ART in a programmatic setting in Kenya. Of 1,848 adults on ART, 1,579 (85 %) initiated d4T-based and 269 (15 %) initiated ZDV-based regimens. One-year incidence of symptomatic PN per 100 person-years was 21.9 (n=236) among d4T users and 6.9 (n=7) among ZDV users (P=0.0002). D4T was associated with 2.7 greater risk of PN than ZDV (adjusted hazard ratio, 2.7, P=0.009). In settings with continued d4T use, such as Africa, the effects of d4T on PN compared to ZDV should be considered when choosing ART regimens.

Evaluation of Hepatic Mitochondria and Hematological Parameters in Zidovudine-Treated B6C3F(1) Mice

The effects of 12-week exposure to zidovudine (AZT) at 400, 500, and 600 mg/kg/d were examined on expression of 542 mitochondria-related genes and mitochondrial DNA (mtDNA) copy number in the liver of male and female B6C3F₁ mice to understand mitochondrial role in sex-related differences in development of lactic acidosis. Plasma lactate levels and hematologic parameters were also examined. Results indicated increased red blood cell (RBC) count in vehicle-treated controls, whereas a dose-related decline in the RBC count was noted in AZT-treated mice compared to the basal levels before treatments began. These decreases were associated with significant dose-related increases in mean corpuscular volume and mean corpuscular hemoglobin levels. This effect was greater in AZT-treated females compared to males. In both sexes, 12-week AZT or vehicle exposure significantly reduced plasma lactate levels compared to the basal levels. Results also showed modest, but significant, changes in the expression of genes associated with apoptosis and lipid metabolism at 600 mg/kg/d AZT. Neither drug nor sex influenced hepatic mtDNA copy number. Altogether, 12-week AZT exposure as high as 600 mg/kg/d did not impair hepatic mitochondria or induce lactic acidosis in B6C3F₁ mice. However, AZT-mediated hematologic toxicity appeared to be greater in females compared to males.

Self-initiation of antiretroviral therapy in the developing world: the involvement of private pharmacies in an HIV program

Background

Self-initiation to antiretroviral treatment (ART) exposes the patient to the risk of drug toxicity, poor adherence to treatment, and escalates the development of drug resistance.

Objectives

To determine the sources of antiretroviral (ARV) drugs by unregistered human immunodeficiency virus (HIV)-infected patients and the extent of ARV self-medication.

Methods

Simulated clients were used to investigate availability and ARV dispensing practice in the private pharmacies in Dar Es Salaam, Tanzania. A total of 480 HIV-infected patients qualifying to start ART were interviewed to find out their previous use of ARV drugs prior to visiting the HIV clinics. Venous blood (2 mL) was collected from each patient who indicated not to have used ARVs in the past (n = 450). Blood samples were analyzed for the presence and levels of nevirapine (NVP).

Results

Only 5.1% (23/451) of pharmacies were found stocking ARVs drugs, among which 4.0% were retail. Drug dispensers in nearly all (15/18) retail pharmacies which stocked ARVs were willing to sell ARVs without prescription. Out of 450 enrolled patients, only 2.7% (12) stated that they had been receiving ARV drugs from HIV clinics but interrupted the ART treatment due to various reasons. From 450 patients, only 10% had quantifiable NVP concentrations in the blood, despite stating in an interview that they had not recently used ARVs.

Conclusion

Prior use of ARV drugs outside HIV clinics was rare among patients attending those centers. However, the results show that some patients could access and use ARV drugs from private pharmacies without undergoing ART eligibility assessment in HIV clinics.

Fatal toxicity from symptomatic hyperlactataemia: a retrospective cohort study of factors implicated with long-term nucleoside reverse transcriptase inhibitor use in a South African hospital

BACKGROUND

In many Sub-Saharan African countries, first-line therapy for HIV may include a nucleoside reverse transcriptase inhibitor (NRTI). Long-term NRTI use is associated with symptomatic hyperlactataemia due to inhibition of mitochondrial DNA polymerase γ, a potentially fatal complication.

OBJECTIVE

The purpose of the study was to evaluate the factors associated with inhospital fatality for HIV inpatients prescribed NRTIs long term who presented with symptomatic hyperlactataemia.

METHODS

We performed a retrospective cohort study at a 900-bed university hospital in South Africa over 4 years (2005-2008). We included HIV inpatients prescribed NRTIs long term who presented with symptomatic hyperlactataemia (long-term NRTI use; lactate >4.0 mmol/L; absence of infectious source; symptoms requiring admission). Data included demographics, medical history, NRTI duration, blood pressure, symptom duration and relevant laboratory data.

RESULTS

Of 79 patients who met inclusion criteria (mean age 38.2 ± 10.5 years, 97% female) there were 46 fatalities (58%). Factors significantly associated with fatality were presence of diabetes mellitus (p = 0.04), lactate ≥10 mmol/L (p = 0.003), pH <7.2 (p = 0.002), creatinine ≥200 μmol/L (p = 0.03) and altered mental status (p = 0.03).

CONCLUSIONS

In this study, NRTI-related symptomatic hyperlactataemia occurred predominantly in females. Mortality was associated with severely elevated lactate (≥10 mmol/L), the degree of acidosis, elevated creatinine, history of diabetes and altered mental status on presentation.

A longitudinal study of stavudine-associated toxicities in a large cohort of South African HIV infected subjects

Background

There has been major improvement in the survival of HIV-1 infected individuals since the South African Government introduced highly active anti-retroviral therapy (HAART) in the public sector in 2004. This has brought new challenges which include the effects of stavudine-related toxicities.

Methods

Prospective analysis of a cohort of 9040 HIV-infected adults who were initiated on HAART at the Themba Lethu Clinic (TLC) in Johannesburg between April 1, 2004 to December 31, 2007, and followed up until June 30, 2008.

Results

Amongst the 9040 study subjects, 8497(94%) were on stavudine based therapy and 5962 (66%) were women. The median baseline CD4 count was 81 cells/mm³ (IQR 29-149). Median follow up on HAART was 19 months (IQR: 9.1-31.6). The proportion of HAART-related side effects for stavudine compared to non-stavudine containing regimens were, respectively: peripheral neuropathy,17.1% vs. 11.2% (p < 0.001); symptomatic hyperlactataemia, 5.7% vs. 2.2% (p < 0.0005); lactic acidosis, 2.5 vs. 1.3% (p = 0.072); lipoatrophy, 7.3% vs. 4.6% (p < 0.05). Among those on stavudine-based regimens, incidence rates for peripheral neuropathy were 12.1 cases/100 person-years (95%CI 7.0-19.5), symptomatic hyperlactataemia 3.6 cases/100 person-years (95%CI 1.2-7.5), lactic acidosis 1.6 cases/100 person-years (95%CI 0.4-5.2) and lipoatrophy 4.6 cases/100 person-years (95%CI 2.1-9.6). Females experienced more toxicity when compared to males in terms of symptomatic hyperlactataemia (p < 0.0001), lactic acidosis (p < 0.0001), lipoatrophy (p < 0.0001) and hypertension (p < 0.05).

Conclusions

We demonstrate significant morbidity associated with stavudine. These data support the latest WHO guidelines, and provide additional evidence for other resource limited HAART rollout programs considering the implementation of non-stavudine based regimens as first line therapy.

Early mortality and AIDS progression despite high initial antiretroviral therapy adherence and virologic suppression in Botswana

Background

Adverse outcomes occurring early after antiretroviral therapy (ART) initiation are common in sub-Saharan Africa, despite reports of high levels of ART adherence in this setting. We sought to determine the relationship between very early ART adherence and early adverse outcomes in HIV-infected adults in Botswana.

Methods

This prospective cohort study of 402 ART-naïve, HIV-infected adults initiating ART at a public HIV clinic in Gaborone, Botswana evaluated the relationship between suboptimal early ART adherence and HIV treatment outcomes in the initial months after ART initiation. Early adherence during the interval between initial ART dispensation and first ART refill was calculated using pill counts. In the primary analysis patients not returning to refill and those with adherence <0.95 were considered to have suboptimal early adherence. The primary outcome was death or loss to follow-up during the first 6 months of ART; a secondary composite outcome included the primary outcome plus incident opportunistic illness (OIs) and virologic failure. We also calculated the percent of early adverse outcomes theoretically attributable to suboptimal early adherence using the population attributable risk percent (PAR%).

Results

Suboptimal early adherence was independently associated with loss to follow-up and death (adjusted OR 2.3, 95% CI 1.1–4.8) and with the secondary composite outcome including incident OIs and virologic failure (adjusted OR 2.6, 95% CI 1.4–4.7). However, of those with early adverse outcomes, less than one-third had suboptimal adherence and approximately two-thirds achieved virologic suppression. The PAR% relating suboptimal early adherence and primary and secondary outcomes were 14.7% and 17.7%, respectively.

Conclusions

Suboptimal early adherence was associated with poor outcomes, but most early adverse outcomes occurred in patients with optimal early adherence. Clinical care and research efforts should focus on understanding early adverse outcomes that occur despite optimal adherence.

A Review of Commonly Prescribed Antiviral and Antiretroviral Agents

Objective:

To review the pharmacologic properties of and uses for the most commonly prescribed antiviral agents.

Data Sources:

A MEDLINE/PubMed search (1966–September 2010) was conducted for English-language articles using the terms HIV, hepatitis, cytomegalovirus (CMV), herpes simplex virus (HSV), antiviral agents, antiretroviral agent, acyclovir, valganciclovir, valacyclovir, interferon, ribavirin, ritonavir, efavirenz, zidovudine, darunavir, lopinavir, tenofovir, raltegravir, lamivudine, atazanavir, and emtricitabine. Book chapters and recent guidelines pertaining to the pathophysiology or pharmacologic properties of antiviral agents were also reviewed.

Study Selection and Data Extraction:

Articles, chapters, and guidelines pertaining to the relevant pharmacologic agents were collected for review.

Data Synthesis:

Viral pathogens affect multiple organs, causing direct and indirect damage by activating an immune response. Unlike bacterial infections, which can be eradicated from the host system, viral infections are not curable. Antiviral treatments are prescribed to reduce morbidity and mortality. There are many antiviral and more than 20 antiretroviral agents currently approved by the FDA. These include acyclovir, valacyclovir, and famciclovir for HSV; ganciclovir, valganciclovir, foscarnet, and cidofovir for CMV; interferon and ribavirin for hepatitis; efavirenz, tenofovir, emtricitabine, atazanavir, darunavir, lopinavir, ritonavir, raltegravir, zidovudine, and lamivudine as first-line agents for HIV.

Conclusions:

Viral illnesses affect a large portion of the population. Given the multitude of drugs available, pharmacists and pharmacy technicians should be educated about common treatment options. Having a strong knowledge of commonly prescribed antiviral drugs allows these frontline professionals to make a significant impact on the quality of care that they provide to their patients and community.

A risk-factor guided approach to reducing lactic acidosis and hyperlactatemia in patients on antiretroviral therapy

Background

Stavudine continues to be used in antiretroviral treatment (ART) regimens in many resource-limited settings. The use of zidovudine instead of stavudine in higher-risk patients to reduce the likelihood of lactic acidosis and hyperlactatemia (LAHL) has not been examined.

Methods

Antiretroviral-naïve, HIV-infected adults initiating ART between 2004 and 2007 were divided into cohorts of those initiated on stavudine- or zidovudine-containing therapy. We evaluated stavudine or zidovudine use, age, sex, body mass index (BMI), baseline CD4 cell count, creatinine, hemoglobin, alanine aminotransferase, and albumin as predictors of time to LAHL with Cox Proportional Hazards (PH) regression models.

Results

Among 2062 patients contributing 2747 patient years (PY), the combined incidence of LAHL was 3.2/100 PY in those initiating stavudine- and 0.34/100 PY in those initiating zidovudine-containing ART (RR 9.26, 95% CI: 1.28–66.93). In multivariable Cox PH analysis, stavudine exposure (HR 14.31, 95% CI: 5.79–35.30), female sex (HR 3.41, 95% CI: 1.89–6.19), higher BMI (HR 3.21, 95% CI: 2.16–4.77), higher creatinine (1.63, 95% CI: 1.12–2.36), higher albumin (HR 1.04, 95% CI: 1.01–1.07), and lower CD4 cell count (HR 0.96, 95% CI: 0.92–1.0) at baseline were associated with higher LAHL rates. Among participants who started on stavudine, switching to zidovudine was associated with lower LAHL rates (HR 0.15, 95% CI: 0.06–0.35). Subgroup analysis limited to women with higher BMI≥25 kg/m2 initiated on stavudine also showed that switch to zidovudine was protective when controlling for other risk factors (HR 0.21, 95% CI .07–0.64).

Conclusions

Stavudine exposure, female sex, and higher BMI are strong, independent predictors for developing LAHL. Patients with risk factors for lactic acidosis have less LAHL while on zidovudine- rather than stavudine-containing ART. Switching patients from stavudine to zidovudine is protective. Countries continuing to use stavudine should avoid this drug in women and patients with higher BMI.

Low extracellular pH induces damage in the pancreatic acinar cell by enhancing calcium signaling

Low extracellular pH (pHe) occurs in a number of clinical conditions and sensitizes to the development of pancreatitis. The mechanisms responsible for this sensitization are unknown. Because abnormal Ca(2+) signaling underlies many of the early steps in the pathogenesis of pancreatitis, we evaluated the effect of decreasing pHe from 7.4 to 7.0 on Ca(2+) signals in the acinar cell. Low pHe significantly increased the amplitude of cerulein-induced Ca(2+) signals. The enhancement in amplitude was localized to the basolateral region of the acinar cell and was reduced by pretreatment with ryanodine receptor (RYR) inhibitors. Because basolateral RYRs also have been implicated in the pathogenesis of pancreatitis, we evaluated the effects of RYR inhibitors on pancreatitis responses in acidic conditions. RYR inhibitors significantly reduced the sensitizing effects of low pHe on zymogen activation and cellular injury. These findings suggest that enhanced RYR-mediated Ca(2+) signaling in the basolateral region of the acinar cell is responsible for the injurious effects of low pHe on the exocrine pancreas.

Stavudine toxicity in women is the main reason for treatment change in a 3-year prospective cohort of adult patients started on first-line antiretroviral treatment in Uganda

PURPOSE

In resource-limited settings, there are only a few antiretroviral treatment (ART) options. Our objective was to evaluate the reasons for first-line ART changes in resource-limited settings.

METHODS

Prospective research cohort of patients initiating ART between April 2004 and April 2005 in Kampala, Uganda. The main endpoint was the substitution of at least 1 drug included in the initial combination.

RESULTS

Five hundred Fifty-nine patients initiated on ART, 70% were female, median CD4+ count 98 (21-163) cells per microliter, median HIV RNA log₁₀ 5.4 (5.0-5.8). 413 (74%) patients were started on stavudine, lamivudine, and nevirapine, and 146 (36%) on zidovudine, lamivudine and efavirenz. One hundred Forty-eight (26.5%) had at least one treatment change (incidence rate 14.3 per 100 person-years; confidence interval: 12.2 to 16.9). The main reason for first treatment change was drug toxicity (n = 91, 61.5%). Stavudine accounted for the majority of the toxicities that led to drug substitution (n = 76, 84%). In the multivariate analysis, being female (P = 0.011) and being stage 3-4 as compared with 1-2 at ART initiation were predictive of stavudine substitution (P = 0.05). There was no difference in virologic outcome in patients who changed due to toxicity compared with those who did not.

CONCLUSIONS

The majority of the treatment changes were due to stavudine-related toxicity. Long-term stavudine use is less well tolerated in women.

Phidisa II Writing Team for Project Phidisa, Ratsela A, Polis M, Dhlomo S, Emery S, Grandits G, Khabo P, Khanyile T, Komati S, Neaton JD, Naidoo LCD, Magongoa D, Qolohle D. A randomized factorial trial comparing 4 treatment regimens in treatment-naive HIV-infected persons with AIDS and/or a CD4 cell count <200 cells/μL in South Africa

BACKGROUND

Few randomized trials comparing antiretroviral therapy (ART) regimens have been conducted in resource-limited settings.

METHODS

In the Republic of South Africa, antiretroviral-naive human immunodeficiency virus (HIV)-infected individuals >14 years old with a CD4 cell count <200 cells/μL or a prior AIDS diagnosis were randomized to receive efavirenz (EFV) or lopinavir/ritonavir (LPV/r) with either zidovudine (ZDV) plus didanosine (ddI) or stavudine (d4T) plus lamivudine (3TC) in an open-label, 2-by-2 factorial study and followed up for the primary outcome of AIDS or death and prespecified secondary outcomes, including CD4 cell count and viral load changes, treatment discontinuation, and grade 4 events.

RESULTS

In total, 1771 persons were randomized and followed up for a median of 24.7 months. AIDS or death occurred in (1) 163 participants assigned EFV and 157 assigned LPV/r (hazard ratio [HR], 1.04 [95% confidence interval {CI}, 0.84-1.30]) and in (2) 170 participants assigned ZDV+ddI and 150 assigned d4T+3TC (HR, 1.15 [95% CI, 0.93-1.44]). HIV RNA levels were lower (P < .001) and CD4 cell counts were greater (P < .01) over follow-up for d4T+3TC versus ZDV+ddI. Rates of potentially life-threatening adverse events and overall treatment discontinuation were similar for d4T+3TC and ZDV+ddI; however, more participants discontinued d4T because of toxicity (12.6%) than other treatments (<5%).

CONCLUSION

EFV and LPV/r are effective components of first-line ART. The poorer viral and immune responses with ZDV+ddI and the greater toxicity-associated discontinuation rate with d4T+3TC suggest that these treatments be used cautiously as initial therapy.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00342355.

Gender-related mortality for HIV-infected patients on highly active antiretroviral therapy (HAART) in rural Uganda

The purpose of this study was to examine gender differences in mortality for human immunodeficiency virus (HIV) patients in rural Western Uganda after six months of highly active antiretroviral therapy (HAART). Three hundred eighty five patients were followed up for six months after initiating HAART. Statistical analysis included descriptive, univariate and multivariate methods, using Kaplan-Meier estimates of survival distribution and Cox proportional hazards regression. Mortality in female patients (9.0%) was lower than mortality in males (13.5%), with the difference being almost statistically significant (adjusted hazard ratio for females 0.55; 95% confidence interval [CI]: 0.28-1.07; P = 0.08). At baseline, female patients had a significantly higher CD4+ cell count than male patients (median 147 cells/μL vs 120 cells/μL; P < 0.01). A higher CD4+ cell count and primary level education were strongly associated with better survival. The higher CD4+ cell count in females may indicate that they accessed HAART services at an earlier stage of their disease progression than males. A borderline statistically significant lower mortality rate in females shows that females fare better on treatment in this context than males. The association between lower mortality and higher CD4+ levels suggest that males are not accessing treatment early enough and that more concerted efforts need to be made by HAART programs to reach male HIV patients.

Stavudine-induced hyperlactatemia/lactic acidosis at a tertiary communicable diseases clinic in South Africa

OBJECTIVES

To determine the incidence, presentation, and outcome of hyperlactatemia and lactic acidosis. DESIGN AND METHODS SETTING: Grey's Hospital, a tertiary level referral institution.

STUDY POPULATION

A chart review of 1719 patients commenced on highly active antiretroviral therapy (HAART) between August 1, 2004, and July 31, 2006. A total of 1000 patients (615 females) received stavudine (d4T)/lamivudine (3TC)/efavirenz (EFV), 719 patients (598 females) received d4T/ 3TC/nevirapine (NVP).

RESULTS

Of the 1719 patients, 152 (8.84%) had an elevated plasma venous lactate (>2.2 mmol/L), 45 patients required admission for lactic acidosis. The overall incidence rate was 13.5 cases per 1000 patient years. The most common presenting symptoms were loss of weight (95%), abdominal pain (78.9%), loss of appetite, and paresthesias (63.8%). The median body mass index (BMI) at commencement of HAART and at onset of symptoms was 24.5 and 26, respectively. A median serum lactate level of 6.08 mmol/L (range 2.3-19.7 mmol/L) was observed at the onset of symptoms.

CONCLUSIONS

High BMI at treatment initiation did not always predict hyperlactatemia. All patients who died had a baseline CD4 count <10 cells/mm(3) at HAART initiation.

The role of serum lactate in the acute care setting

Acute care services are increasingly faced with the double burden of high patient acuity and limited resources. Early identification of patients who are sick or who have the potential to deteriorate rapidly is crucial so that these resources may be allocated to those in greatest need. Traditional measures of illness and end points of resuscitation, such as vital signs, often fail to identify occult hypoperfusion with certain disease processes associated with high morbidity and mortality. Thus, biochemical markers that may predict illness earlier are becoming more relevant. We present a review of the evidence behind use of the serum lactate level in this setting.

Micronutrients and HIV infection

The immune system requires several essential micronutrients to maintain an effective immune response. HIV infection destroys the immune system and promotes nutritional deficiencies, which further impair immunity. This article reviews the role of several micronutrients (vitamins A, C, E and D, the B vitamins, and minerals, selenium, iron and zinc) that are relevant for maintaining immune function. In addition, the deficiencies of these micronutrients have been associated with faster progression of HIV-1 disease. This review examines the evidence from observational studies of an association between micronutrient status and HIV disease, as well as the effectiveness of micronutrient supplementation on HIV-disease progression, pregnancy outcomes and nutritional status, among others, utilizing randomized clinical trials. Each micronutrient is introduced with a summary of its functions in human physiology, followed by the presentation of studies conducted in HIV-infected patients in relation to this specific micronutrient. Overall findings and recommendations are then summarized.

Reduced referral and case fatality rates for severe symptomatic hyperlactataemia in a South African public sector antiretroviral programme: a retrospective observational study

Background

Interventions to promote prevention and earlier diagnosis of severe symptomatic hyperlactataemia (SHL) were implemented in the Western Cape provincial antiretroviral programme (South Africa) from 2004. Interventions included clinician education, point-of-care lactate meters, switch from stavudine to zidovudine in high risk patients and stavudine dose reduction. This study assessed trends in referral rate, severity at presentation and case fatality rate for severe SHL.

Methods

Retrospective study of severe SHL cases diagnosed at a referral facility from 1 January 2003 to 31 December 2008. Severe SHL was defined as patients with compatible symptoms and serum lactate ≥ 5 mmol/l attributable to antiretroviral therapy (ART). Cumulative ART exposure at referring ART clinics was used to calculate referral rates.

Results

There were 254 severe SHL cases. The referral rate (per thousand patient years [py] ART exposure) peaked in 2005 (20.4/1000py), but fell to 1.3/1000py by 2008 (incidence rate ratio [IRR] = 0.07, 95%CI 0.04-0.11). In 2003, 66.7% of cases presented with a standard bicarbonate (SHCO₃) level <15 mmol/l, but this fell to 12.5% by 2008 (p for trend < 0.001). Case fatality rate fell from a peak of 33.3% in 2004 to 0% in 2008 (p for trend = 0.002).

Conclusions

These trends suggest the interventions were associated with reduced referral, less severe metabolic acidosis at presentation and improved survival.

HIV-1 subtype C-infected individuals maintaining high viral load as potential targets for the "test-and-treat" approach to reduce HIV transmission

The first aim of the study is to assess the distribution of HIV-1 RNA levels in subtype C infection. Among 4,348 drug-naïve HIV-positive individuals participating in clinical studies in Botswana, the median baseline plasma HIV-1 RNA levels differed between the general population cohorts (4.1-4.2 log(10)) and cART-initiating cohorts (5.1-5.3 log(10)) by about one log(10). The proportion of individuals with high (> or = 50,000 (4.7 log(10)) copies/ml) HIV-1 RNA levels ranged from 24%-28% in the general HIV-positive population cohorts to 65%-83% in cART-initiating cohorts. The second aim is to estimate the proportion of individuals who maintain high HIV-1 RNA levels for an extended time and the duration of this period. For this analysis, we estimate the proportion of individuals who could be identified by repeated 6- vs. 12-month-interval HIV testing, as well as the potential reduction of HIV transmission time that can be achieved by testing and ARV treating. Longitudinal analysis of 42 seroconverters revealed that 33% (95% CI: 20%-50%) of individuals maintain high HIV-1 RNA levels for at least 180 days post seroconversion (p/s) and the median duration of high viral load period was 350 (269; 428) days p/s. We found that it would be possible to identify all HIV-infected individuals with viral load > or = 50,000 (4.7 log(10)) copies/ml using repeated six-month-interval HIV testing. Assuming individuals with high viral load initiate cART after being identified, the period of high transmissibility due to high viral load can potentially be reduced by 77% (95% CI: 71%-82%). Therefore, if HIV-infected individuals maintaining high levels of plasma HIV-1 RNA for extended period of time contribute disproportionally to HIV transmission, a modified "test-and-treat" strategy targeting such individuals by repeated HIV testing (followed by initiation of cART) might be a useful public health strategy for mitigating the HIV epidemic in some communities.

Nutritional aspects of HIV-associated wasting in sub-Saharan Africa

The twin global epidemics of HIV infection and food scarcity disproportionately affect sub-Saharan Africa, and a significant proportion of patients who require antiretroviral therapy (ART) are malnourished because of a combination of HIV-associated wasting and inadequate nutrient intake. Protein-calorie malnutrition, the most common form of adult malnutrition in the region, is associated with significant morbidity and compounds the immunosuppressive effects of HIV. A low body mass index (BMI), a sign of advanced malnutrition, is an independent predictor of early mortality (<6 mo) after ART initiation in several analyses, and recent studies show an association between early weight gain when receiving ART and improved treatment outcomes. The cause of the observed increase in mortality is uncertain, but it is likely due in part to malnutrition-induced immune system dysfunction, a higher burden of opportunistic infections, and metabolic derangements. In this article, we describe the epidemiology of HIV infection and malnutrition in sub-Saharan Africa, potential causes of increased mortality after ART initiation among patients with a low BMI, recent studies on post-ART weight gain and treatment outcome, and trials of macronutrient supplementation from the region. We close by highlighting priority areas for future research.

Apoptosis: a clinically useful measure of antiretroviral drug toxicity?

Antiretroviral therapy (ART) has improved life expectancy with HIV infection, but long-term toxicities associated with these medications are now a major global disease burden. There is a clear need to develop useful methods for monitoring patients on antiretroviral drugs for early signs of toxicity. Assays with predictive utility -- allowing therapy to be changed before serious end organ damage occurs -- would be ideal. Attempts to develop biochemical methods of monitoring ART toxicity have concentrated on the mitochondrial toxicity of nucleoside analogue reverse transcriptase inhibitors and have not generally lead to assays with widespread clinical applications. For example, plasma lactate and peripheral blood measurements of mitochondrial DNA associate with exposure to potentially toxic nucleoside analogue reverse transcriptase inhibitors but have not reliably predicted clinical toxicity. Better assays are needed, including markers of toxicity from additional drug classes. Apoptosis may be a potential marker of ART toxicity. Increased apoptosis has been demonstrated both in vitro and in vivo in association with various antiretroviral drug classes and a range of clinical toxicities. However, quantifying apoptosis on biopsy specimens of tissue (such as adipose tissue) is impractical for patient monitoring. Novel assays have been described that can quantify apoptosis using minute tissue samples and initial results from clinical samples suggest peripheral blood may have utility in predicting ART toxicities. The limitations and potential of such techniques for monitoring patients for drug side effects will be discussed.

Non-nucleoside reverse transcriptase inhibitor outcomes among combination antiretroviral therapy-treated adults in Botswana

BACKGROUND

National initiatives offering non-nucleoside reverse transcriptase inhibitor (NNRTI)-based combination antiretroviral therapy (cART) have expanded in sub-Saharan Africa. The Tshepo study is the first clinical trial evaluating the long-term efficacy and tolerability of efavirenz versus nevirapine-based cART among adults in Botswana.

METHODS

A 3-year randomized study (n = 650) using a 3 x 2 x 2 factorial design comparing efficacy and tolerability among: (i) zidovudine/lamivudine versus zidovudine/didanosine versus stavudine/lamivudine; (ii) efavirenz versus nevirapine; and (iii) community-based supervision versus standard adherence strategies. This paper focuses on comparison (ii).

RESULTS

There was no significant difference by assigned NNRTI in time to virological failure with resistance (log-rank P = 0.14), nevirapine versus efavirenz [risk ratio (RR) 1.54, 95% CI 0.86-2.70]. Rates of virological failure with resistance were 9.6% nevirapine-treated (95% CI 6.8-13.5) versus 6.6% efavirenz-treated (95% CI 4.2-10.0) at 3 years. Women receiving nevirapine-based cART trended towards higher virological failure rates when compared with efavirenz-treated women, Holm-corrected (log-rank P = 0.072), nevirapine versus efavirenz (RR 2.22, 95% CI 0.94-5.00). A total of 139 patients had 176 treatment-modifying toxicities, with a shorter time to event in nevirapine-treated versus efavirenz-treated patients (RR 1.85, 1.20-2.86; log-rank P = 0.0002).

CONCLUSION

Tshepo-treated patients had excellent overall immunological and virological outcomes, and no significant differences were observed by randomized NNRTI comparison. Nevirapine-treated women trended towards higher virological failure with resistance compared with efavirenz-treated women. Nevirapine-treated adults had higher treatment modifying toxicity rates when compared with those receiving efavirenz. Nevirapine-based cART can continue to be offered to women in sub-Saharan Africa if patient education concerning toxicity is emphasized, routine safety monitoring chemistries are performed and the potential risk of efavirenz-related teratogenicity is considered.

CD4+ T-cell-guided structured treatment interruptions of antiretroviral therapy in HIV disease: projecting beyond clinical trials

BACKGROUND

International trials have shown that CD4+ T-cell-guided structured treatment interruptions (STI) of antiretroviral therapy (ART) lead to worse outcomes than continuous treatment. We simulated continuous ART and STI strategies with higher CD4+ T-cell interruption/reintroduction thresholds than those assessed in actual trials.

METHODS

Using a model of HIV, we simulated cohorts of African adults with different baseline CD4+ T-cell counts (< or = 200; 201-350; and 351-500 cells/microl). We varied ART initiation criteria (immediate; CD4+ T-cell count < 350 cells/microl or > or = 350 cells/microl with severe HIV-related disease; and CD4+ T-cell count <200 cells/microl or > or = 200 cells/microl with severe HIV-related disease), and ART interruption/reintroduction thresholds (350/250; 500/350; and 700/500 cells/microl). First-line therapy was non-nucleoside reverse transcriptase inhibitor (NNRTI)-based and second-line therapy was protease inhibitor (PI)-based.

RESULTS

STI generally reduced life expectancy compared with continuous ART. Life expectancy increased with earlier ART initiation and higher interruption/reintroduction thresholds. STI reduced life expectancy by 48-69 and 11-30 months compared with continuous ART when interruption/reintroduction thresholds were 350/250 and 500/350 cells/microl, depending on ART initiation criteria. When patients interrupted/reintroduced ART at 700/500 cells/microl, life expectancies ranged from 2 months lower to 1 month higher than continuous ART. STI-related life expectancy increased with decreased risk of virological resistance after ART interruptions.

CONCLUSIONS

STI with NNRTI-based regimens was almost always less effective than continuous treatment, regardless of interruption/reintroduction thresholds. The risks associated with STI decrease only if patients start ART earlier, interrupt/reintroduce treatment at very high CD4+ T-cell thresholds (700/500 cells/microl) and use first-line medications with higher resistance barriers, such as PIs.

Hepatic profile analyses of tipranavir in Phase II and III clinical trials

Background

The risk and course of serum transaminase elevations (TEs) and clinical hepatic serious adverse event (SAE) development in ritonavir-boosted tipranavir (TPV/r) 500/200 mg BID recipients, who also received additional combination antiretroviral treatment agents in clinical trials (TPV/r-based cART), was determined.

Methods

Aggregated transaminase and hepatic SAE data through 96 weeks of TPV/r-based cART from five Phase IIb/III trials were analyzed. Patients were categorized by the presence or absence of underlying liver disease (+LD or -LD). Kaplan-Meier (K-M) probability estimates for time-to-first US National Institutes of Health, Division of AIDS (DAIDS) Grade 3/4 TE and clinical hepatic SAE were determined and clinical actions/outcomes evaluated. Risk factors for DAIDS Grade 3/4 TE were identified through multivariate Cox regression statistical modeling.

Results

Grade 3/4 TEs occurred in 144/1299 (11.1%) patients; 123/144 (85%) of these were asymptomatic; 84% of these patients only temporarily interrupted treatment or continued, with transaminase levels returning to Grade ≤ 2. At 96 weeks of study treatment, the incidence of Grade 3/4 TEs was higher among the +LD (16.8%) than among the -LD (10.1%) patients. K-M analysis revealed an incremental risk for developing DAIDS Grade 3/4 TEs; risk was greatest through 24 weeks (6.1%), and decreasing thereafter (>24-48 weeks: 3.4%, >48 weeks-72 weeks: 2.0%, >72-96 weeks: 2.2%), and higher in +LD than -LD patients at each 24-week interval. Treatment with TPV/r, co-infection with hepatitis B and/or C, DAIDS grade >1 TE and CD4⁺ > 200 cells/mm³ at baseline were found to be independent risk factors for development of DAIDS Grade 3/4 TE; the hazard ratios (HR) were 2.8, 2.0, 2.1 and 1.5, respectively. Four of the 144 (2.7%) patients with Grade 3/4 TEs developed hepatic SAEs; overall, 14/1299 (1.1%) patients had hepatic SAEs including six with hepatic failure (0.5%). The K-M risk of developing hepatic SAEs through 96 weeks was 1.4%; highest risk was observed during the first 24 weeks and decreased thereafter; the risk was similar between +LD and -LD patients for the first 24 weeks (0.6% and 0.5%, respectively) and was higher for +LD patients, thereafter.

Conclusion

Through 96 weeks of TPV/r-based cART, DAIDS Grade 3/4 TEs and hepatic SAEs occurred in approximately 11% and 1% of TPV/r patients, respectively; most (84%) had no significant clinical implications and were managed without permanent treatment discontinuation. Among the 14 patients with hepatic SAE, 6 experienced hepatic failure (0.5%); these patients had profound immunosuppression and the rate appears higher among hepatitis co-infected patients. The overall probability of experiencing a hepatic SAE in this patient cohort was 1.4% through 96 weeks of treatment. Independent risk factors for DAIDS Grade 3/4 TEs include TPV/r treatment, co-infection with hepatitis B and/or C, DAIDS grade >1 TE and CD4⁺ > 200 cells/mm³ at baseline.

Trial registration

US-NIH Trial registration number: NCT00144170

Fatal lactic acidosis associated with the use of combination oral medications to treat reactivation of hepatitis B

Oral nucleos(t)ide analogs for the treatment of hepatitis B virus (HBV) infection are well tolerated with minimal side effects. These agents do carry a Food and Drug Administration "black box" warning about the development of fatal lactic acidosis on the basis of data from the human immunodeficiency virus literature. However, no previously published cases of this lethal side effect have been reported in patients undergoing HBV treatment using the current Food and Drug Administration-approved HBV medications. We report a case of HBV reactivation after chemotherapy for leukemia, and the development of fatal lactic acidosis attributed to the use of combination oral HBV medications.

Adult combination antiretroviral therapy in sub-Saharan Africa: lessons from Botswana and future challenges

Numerous national public initiatives offering first-line combination antiretroviral therapy (cART) for HIV infection have commenced in sub-Saharan Africa since 2002. Presently, 2.1 million of an estimated seven million Africans in need of cART are receiving treatment. Analyses from the region report favorable clinical/treatment outcomes and impressive declines in AIDS-related mortality among HIV-1-infected adults and children receiving cART. While immunologic recovery, virologic suppression and cART adherence rates are on par with resource-rich settings, loss to follow-up and high mortality rates, especially within the first 6 months of treatment, remain a significant problem. Over the next decade, cART coverage rates are expected to improve across the region, with attendant increases in healthcare utilization for HIV- and non-HIV-related complications and the need for expanded laboratory and clinical services. Planned and in-progress trials will evaluate the use of cART to prevent primary HIV-1 infection with so-called 'test and treat' expansions of coverage and treatment. Education and training programs as well as patient-retention strategies will need to be strengthened as national cART programs are expanded and more people require lifelong monitoring and care.

Do the socioeconomic impacts of antiretroviral therapy vary by gender? A longitudinal study of Kenyan agricultural worker employment outcomes

BACKGROUND

As access to antiretroviral therapy (ART) has grown in Africa, attention has turned to evaluating the socio-economic impacts of ART. One key issue is the extent to which improvements in health resulting from ART allows individuals to return to work and earn income. Improvements in health from ART may also be associated with reduced impaired presenteeism, which is the loss of productivity when an ill or disabled individual attends work but accomplishes less at his or her usual tasks or shifts to other, possibly less valuable, tasks.

METHODS

Longitudinal data for this analysis come from company payroll records for 97 HIV-infected tea estate workers (the index group, 56 women, 41 men) and a comparison group of all workers assigned to the same work teams (n = 2485, 1691 men, 794 women) for a 37-month period covering two years before and one year after initiating ART. We used nearest neighbour matching methods to estimate the impacts of HIV/AIDS and ART on three monthly employment outcomes for tea estate workers in Kenya--days plucking tea, days assigned to non-plucking assignments, and kilograms harvested when plucking.

RESULTS

The female index group worked 30% fewer days plucking tea monthly than the matched female comparison group during the final 9 months pre-ART. They also worked 87% more days on non-plucking assignments. While the monthly gap between the two groups narrowed after beginning ART, the female index group worked 30% fewer days plucking tea and about 100% more days on non-plucking tasks than the comparison group after one year on ART. The male index group was able to maintain a similar pattern of work as their comparison group except during the initial five months on therapy.

CONCLUSION

Significant impaired presenteeism continued to exist among the female index group after one year on ART. Future research needs to explore further the socio-economic implications of HIV-infected female workers on ART being less productive than the general female workforce over sustained periods of time.

A new era of antiretroviral drug toxicity

The spectrum of drugs used in HIV-infected patients has dramatically changed since triple antiretroviral combinations were introduced, albeit at the expense of some severe adverse events, in 1996. Abandonment of stavudine in countries that can afford it, new drugs from new classes with a wide therapeutic window and the impressive scale-up of drug access in resource-limited settings are several of the key new events. Drug safety is likely to be the most important factor to distinguish one antiretroviral regimen from another. We review life-threatening adverse events, adverse events of new investigational or recently marketed drugs, adverse events with a genetic component and tissue-specific adverse events of fat, heart, bone, kidney and liver.

Response to zidovudine/didanosine-containing combination antiretroviral therapy among HIV-1 subtype C-infected adults in Botswana: two-year outcomes from a randomized clinical trial

BACKGROUND

Numerous national antiretroviral (ARV) treatment initiatives offering protease inhibitor-sparing combination antiretroviral therapy (cART) have recently commenced in southern Africa, the first of which began in Botswana in January 2002. Evaluation of the efficacy and tolerability of various protease inhibitor-sparing cART regimens requires intensive study in the region, as does investigation of the development of drug resistance and the optimal means of sustaining adherence. The "Tshepo" Study is the first large-scale, randomized, clinical trial that addresses these important issues among HIV-1 subtype C-infected ARV treatment-naive adults in southern Africa.

METHODS

The Tshepo Study is a completed, open-labeled, randomized study that enrolled 650 ARV-naive adults between December 2002 and 2004. The study is a 3 x 2 x 2 factorial design comparing the efficacy and tolerability among factors: (1) 3 combinations of nucleoside reverse transcriptase inhibitors (NRTIs): zidovudine (ZDV) + lamivudine (3TC), ZDV + didanosine (ddI), and stavudine (d4T) + 3TC; (2) 2 different nonnucleoside reverse transcriptase inhibitors (NNRTIs): nevirapine and efavirenz; and (3) 2 different adherence strategies: the current national "standard of care" versus an "intensified adherence strategy" incorporating a "community-based directly observed therapy." Study patients were stratified into 2 balanced CD4 T-cell count groups: less than 201 versus 201-350 cells per cubic millimeter with viral load greater than 55,000 copies per milliliter. Following Data Safety Monitoring Board recommendations in April 2006, ZDV/ddI-containing arms were discontinued due to inferiority in primary end point, namely, virologic failure with resistance. We report both overall data and pooled data from patients receiving ZDV/ddI- versus ZDV/3TC- and d4T/3TC-containing cART through April 1, 2006.

RESULTS

Four hundred fifty-one females (69.4%) and 199 males with a median age of 33.3 years were enrolled into the study. The median follow-up as of April 1, 2006, was 104 weeks, and loss to follow-up rate at 2 years was 4.1%. The median baseline CD4 T-cell count was 199 cells per cubic millimeter [interquartile ratio (IQR) 136-252], and the median plasma HIV-1 RNA level was 193,500 copies per milliliter (IQR 69-250, 472-500). The proportion of participants with virologic failure and genotypic resistance mutations was 11% in those receiving ZDV/ddI-based cART versus 2% in those receiving either ZDV/3TC- or d4T/3TC-based cART (P = 0.002). The median CD4 T-cell count increase at 1 year was 137 cells per cubic millimeter (IQR 74-223) and 199 cells per cubic millimeter (IQR 112-322) at 2 years with significantly lower gain in the ZDV/ddI arm. At 1 and 2 years, respectively, 92.0% and 88.8% of patients had an undetectable plasma HIV-1 RNA level (< or = 400 copies/mL). Kaplan-Meier survival estimates at 1 and 2 years were 96.6% and 95.4%. One hundred twenty patients (18.2%) had treatment-modifying toxicities, of which the most common were lipodystrophy, anemia, neutropenia, and Stevens-Johnson syndrome. There was a trend toward difference in time to treatment-modifying toxicity by pooled dual-NRTI combination and no difference in death rates.

CONCLUSIONS

The preliminary study results show overall excellent efficacy and tolerability of NNRTI-based cART among HIV-1 subtype C-infected adults. ZDV/ddI-containing cART, however, is inferior to the dual NRTIs d4T/3TC or ZDV/3TC when used with an NNRTI for first-line cART.