Estimated glomerular filtration rate, chronic kidney disease and antiretroviral drug use in HIV-positive patients

Associations between plasma tenofovir concentration and renal function markers in HIV-infected women

Background

Tenofovir disoproxil fumarate (TDF) has been associated with kidney tubular dysfunction and reduced renal function. Limited studies were performed in Europe and Asia that related plasma tenofovir (TFV) concentration with renal function; no such studies to date have been performed on Africans.

Objective

To investigate the correlation between plasma tenofovir (TFV) concentration and certain renal function markers in HIV-infected women on TDF antiretroviral therapy (ART). These markers were also compared to a HIV-uninfected control group.

Methods

HIV-infected women (n = 30) on TDF-based ART were matched with 30 controls for age and body mass index. Renal markers analysed were estimated glomerular filtration rate (eGFR), creatinine clearance (CrCl), serum creatinine, albuminuria, glucosuria, serum urea, serum uric acid, urine sodium and maximum tubular reabsorption of phosphate. Baseline eGFR and CrCl data were obtained retrospectively for the HIV-infected women. Plasma TFV was assayed using a validated HPLC-MS/MS method. Stepwise regression, Mann-Whitney test, unpaired and paired t-tests were applied in the statistical analyses.

Results

TFV concentration was independently associated with albuminuria (adjusted r² = 0.339; p = 0.001) in HIV-infected women. In the adjusted (weight) analysis, eGFR (p = 0.038), CrCl (p = 0.032) and albuminuria (p = 0.048) were significantly higher in HIV-infected compared to the uninfected women, but eGFR was abnormally high in HIV-infected women. Both eGFR (p < 0.001) and CrCl (p = 0.008) increased from baseline to follow-up in HIV-infected women.

Conclusion

Plasma TFV concentration was associated with increased albuminuria in HIV-infected women in this sub-study. Both eGFR and CrCl were increased in HIV-infected women from baseline. These findings should be confirmed in larger studies, and hyperfiltration in HIV-infected women warrants further investigation.

Exploratory Analysis for the Evaluation of Estimated Glomerular Filtration Rate, Cholesterol and Triglycerides after Switching from Tenofovir/Emtricitabine plus Atazanavir/Ritonavir (ATV/r) to Abacavir/Lamivudine plus ATV/r in Patients with Preserved Renal Function

BACKGROUND AND OBJECTIVES

Renal toxicity due to tenofovir (TDF) has been largely described in patients with HIV infection. However, other antiretroviral drugs (such as atazanavir [ATV], especially when boosted by ritonavir, ATV/r) could perpetuate some degrees of renal impairment with or without TDF co-administration. Also, possible benefits of stopping TDF in patients without renal diseases is not well known. This study aimed at exploring evolution of renal function and lipid profile after switching from tenofovir/emtricitabine (TDF/FTC) to abacavir/lamivudine (ABC/3TC), maintaining the ATV/r component of the regimen.

METHODS

Patients in the Italian MASTER Cohort, who switched from TDF/FTC plus ATV/r to ABC/3TC plus ATV/r were included, provided that major renal diseases were not diagnosed before switching (i.e., baseline). Serum creatinine, estimated glomerular filtration rate (eGFR), total cholesterol, HDL and triglycerides were evaluated at baseline and at month 18 after switching.

RESULTS

126 patients were selected (80% males). Patients were mostly Italians (92%). 79% had undetectable HIV-RNA and 44% were co-infected by HBV and/or HCV. Median age at switch was 47 years (IQR 43-55). A small but significant decrease in serum creatinine [from 1.06 mg/dl (SD: 0.3) to 0.94 mg/dl (SD: 0.2); p<0.001] with an improvement in eGFR [from 86.8 ml/min (SD: 33) to 96.4 ml/min (SD: 37); p<0.001] were observed in per protocol analysis at month 18. Also ITT analysis showed a decrease in mean serum creatinine [from 1.08 mg/dl (SD: 0.35) to 0.95 mg/dl (SD: 0.24); p<0.001] with an improvement in mean eGFR [from 86.9 ml/min/1.73m2 (SD: 24.11) to 95.8 ml/min/1.73m2 (SD: 19.99); p<0.001]. Total cholesterol increased [from 188 mg/dl (SD: 42) to 206 mg/dl (SD: 44); p<0.001] but also HDL increased as well [from 46 mg/dl (SD: 14) to 54 mg/dl (SD: 19); p=0.015]. An increase in triglycerides concentration was observed [from 162 mg/dl (SD: 144) to 214 mg/dl (SD: 109); p=0.027] in per protocol analysis. Also ITT analysis showed increases of both total cholesterol [from 187 mg/dl (SD: 43.69) to 203 mg/dl (SD: 44.10); p<0.001] and HDL fraction [from 46 mg/dl (SD: 15.49) to 52 mg/dl (SD: 17.13); p=0.002] at month 18.

CONCLUSION

This analysis reports an improvement in eGFR and an increase in total cholesterol and HDL fraction at month 18 after switching to ABC/3TC plus ATV/r. Given the fact that renal function was not significantly affected at baseline, our findings may suggest the utility of a proactive switch from TDF to ABC, when otherwise indicated, in patients who cannot avoid using a nucleoside backbone.

Polymorphisms associated with renal adverse effects of antiretroviral therapy in a Southern Brazilian HIV cohort

OBJECTIVE

This study evaluated the impact of seven single nucleotide polymorphisms in five candidate genes (ABCB1, ABCC2, ABCC4, SLC22A6, and SLC22A11) in relation to nephrotoxicity associated with highly active antiretroviral therapy (HAART) in HIV-infected individuals.

METHODS

The following single nucleotide polymorphisms were genotyped by real-time PCR: ABCB1 rs1045642, ABCC2 rs717620 and rs2273697, ABCC4 rs1751034 and rs3742106, SLC22A6 rs11568626, and SLC22A11 rs11231809 in 507 HIV-infected patients from the city of Porto Alegre, Southern Brazil, receiving HAART for, at least, 1 year.

RESULTS

From the 507 HIV-infected patients recruited, 19.1% presented a reduction in estimated glomerular filtration rate (eGFR). A total of 16 (3.2%) patients fulfilled the criteria for chronic kidney disease (defined as eGFR<60 ml/min/1.73 m). Individuals carrying at least one T allele of ABCC2 -24 C>T (rs717620) presented lower eGFR than C/C homozygotes (104 ± 22 vs. 108 ± 22 ml/min/1.73 m, independent-samples t-test, P=0.040). In multivariate analysis, the predictors associated with decreased eGFR were time of treatment, tenofovir use, atazanavir/ritonavir use, and carrying one T allele of ABCC2 -24 C>T.

CONCLUSION

Our data support the importance of genetic factors in the etiology of nephrotoxicity in patients treated with HAART. Studies to verify treatment implications of genotyping before HAART initiation may be advisable to guide the selection of an appropriate antiretroviral therapy regimen.

Frequent injection cocaine use increases the risk of renal impairment among hepatitis C and HIV coinfected patients

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Objective:

To examine the association between injection cocaine use, hepatitis C virus (HCV) infection, and chronic renal impairment (CRI).

Design:

Prospective observational cohort study of HIV–HCV coinfected patients.

Methods:

Data from 1129 participants in the Canadian Co-Infection Cohort with baseline and follow-up serum creatinine measurements between 2003 and 2014 were analyzed. Prevalent and incident cohorts were created to examine the association between self-reported past, current, and cumulative cocaine use and chronic HCV with CRI. CRI was defined as an estimated glomerular filtration rate below 70 ml/min per 1.73 m². Multivariate logistic regression was used to calculate odds ratios, and discrete-time proportional-hazards models were used to calculate hazard ratios for cocaine use, in the two respective cohorts, adjusted for HCV RNA and important demographic, HIV disease stage, and comorbidity confounders.

Results:

Eighty-seven participants (8%) had prevalent CRI. Past injection cocaine use was associated with a two-fold greater risk of prevalent CRI [odds ratio 2.03, 95% confidence interval (CI) 0.96, 4.32]. During follow-up, 126 of 1061 participants (12%) developed incident CRI (31 per 1000 person-years). Compared to nonusers, heavy (≥ 3 days/week) and frequent injection cocaine users (≥75% of follow-up time) experienced more rapid progression to CRI (hazard ratio 2.65, 95% CI 1.35, 5.21; and hazard ratio 1.82, 95% CI 1.07, 3.07, respectively). There was no association between chronic HCV and CRI in either cohort.

Conclusion:

After accounting for HCV RNA, frequent and cumulative injection cocaine abuse was associated with CRI progression and should be taken into consideration when evaluating impaired renal function in HIV–HCV coinfection.

Integrase inhibitor versus protease inhibitor based regimen for HIV-1 infected women (WAVES): a randomised, controlled, double-blind, phase 3 study

BACKGROUND

Women are under-represented in HIV antiretroviral therapy (ART) studies. Guidelines for selection of ART as initial therapy in patients with HIV-1 infection do not contain sex-specific treatment. We aimed to assess the safety and efficacy of the single tablet integrase inhibitor regimen containing elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate compared with a boosted protease inhibitor regimen of ritonavir-boosted atazanavir with emtricitabine and tenofovir disoproxil fumarate.

METHODS

In this international, randomised, controlled, double-blind, phase 3 study (Women AntiretroViral Efficacy and Safety study [WAVES]), we recruited treatment-naive HIV-infected women with an estimated creatinine clearance of 70 mL/min or higher from 80 centres in 11 countries. Women were randomly assigned (1:1) to receive elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (integrase inhibitor regimen) or ritonavir-boosted atazanavir with emtricitabine and tenofovir disoproxil fumarate (protease inhibitor based regimen); regimens were masked with matching placebos. Randomisation was done by a computer-generated allocation sequence (block size four) and was stratified by HIV-1 RNA viral load and race. Investigators, patients, study staff, and those assessing outcomes were masked to treatment group. All participants who received one dose of study drug were included in the primary efficacy and safety analyses. The main outcome was the proportion of patients with plasma HIV-1 RNA less than 50 copies per mL at week 48 as defined by US Food and Drug Administration snapshot algorithm (prespecified non-inferiority margin of 12%). This study is registered with ClinicalTrials.gov, number NCT01705574.

FINDINGS

Between Nov 28, 2012, and March 12, 2014, 575 women were enrolled. 289 were randomly assigned to receive the integrase inhibitor regimen and 286 to receive the protease inhibitor based regimen. 252 (87%) women in the integrase inhibitor group had plasma HIV-1 RNA less than 50 copies per mL at week 48 compared with 231 (81%) women in the protease inhibitor group (adjusted difference 6·5%; 95% CI 0·4-12·6). No participant had virological failure with resistance in the integrase inhibitor group compared with three participants ([1%]; all Met184Val/Ile) in the protease inhibitor group. 19 women in the protease inhibitor group discontinued because of adverse events compared with five in the integrase inhibitor group.

INTERPRETATION

WAVES shows that clinical trials of ART regimens in global and diverse populations of treatment-naive women are possible. The findings support guidelines recommending integrase inhibitor based regimens in first-line antiretroviral therapy.

FUNDING

Gilead Sciences.

Increased non-HDL-C level linked with a rapid rate of renal function decline in HIV-infected patients

BACKGROUND

The risk of developing CKD is increased in HIV-infected patients; however, the relationship between renal function decline and lipid abnormalities currently remains unclear in these patients.

METHODS

A retrospective cohort study was conducted on 661 HIV-infected patients, whose estimated glomerular filtration rates (eGFRs) were consecutively measured over 6 years. The rate of declines in eGFR per year was calculated, with decreases being evaluated using a linear mixed effect model. The distribution of decreases in eGFR ≥ 30 % from baseline during the follow-up period was compared across quartiles of non-high-density lipoprotein cholesterol (HDL-C) levels using the Cochran-Armitage test. A multivariate logistic regression model was built to examine the relationship between dyslipidemia and decreases in eGFR.

RESULTS

The prevalence of CKD increased from 8.5 to 21.2 % during the follow-up. The average of 6 annual eGFR decline rates was 2.01 ± 0.09 ml/min/1.73 m²/year, which was more than 6-fold higher than that of age-matched controls. The distribution of decreases in eGFR significantly increased across the quartiles of non-HDL-C (p value for trend = 0.0359). Non-HDL-C levels greater than the median value of the cohort were identified as a significant risk factor for decreased eGFR [odds ratio (95 % confidence interval), 1.77 (1.07-3.00)].

CONCLUSION

Increased non-HDL-C levels are a risk factor for renal function decline in HIV-infected patients.

Estimated Glomerular Filtration Rate Trajectories in HIV-Infected Subjects Treated With Different Ritonavir-Boosted Protease Inhibitors and Tenofovir Disoproxil Fumarate or Abacavir

The aim of the study was to evaluate in human immunodeficiency virus (HIV)-infected patients estimated glomerular filtration rate (eGFR) trajectories during treatment with different protease inhibitors (PIs) or a non-nucleoside reverse transcriptase inhibitor (NNRTI) plus tenofovir (TDF) or abacavir (ABC) and lamivudine or emtricitabine (xTC).Retrospective study of patients followed at a single clinical center; all patients who started TDF or ABC for the first time with a NNRTI or lopinavir/r (LPV/r) or atazanavir/r (ATV/r) or darunavir/r (DRV/r), for whom at least 1 eGFR value before the start and during the studied treatment was known, were included in this analysis. eGFR was calculated by means of the CKD-EPI formula. Univariate and multivariate mixed linear model (MLM) was applied to estimate eGFR slope with the considered antiretroviral treatment.In the 1658 patients treated with TDF/xTC (aged 43 [37-48] years, with an eGFR of 105 [96; 113] mL/min/1.73 m, 80% males, 92% Caucasians, 10% coinfected with HCV, 4% with diabetes, 11% with hypertension, 38% naive for antiretroviral therapy (ART), 37% with HIV-RNA <50 copies/mL) the median follow-up was 2.5 (1.2-4.6) years. Their adjusted eGFR slopes (95% CI) were -1.26 (-1.58; -0.95), -0.43 (-1.20; +0.33), -0.86 (-1.28; -0.44), and -0.20 (-0.42; +0.02) mL/min/1.73 m per year in patients treated with ATV/r, DRV/r, LPV/r, and NNRTI, respectively. Patients receiving ATV/r or LPV/r had a greater adjusted decline in eGFR compared with those receiving NNRTIs (difference -1.06 [-1.44; -0.69] mL/min/1.73 m per year, P <0.001; and -0.66 [-1.13; -0.20] mL/min/1.73 m per year, P = 0.005, respectively); adjusted eGFR slopes were similar in patients receiving DRV/r and in those receiving NNRTIs. Patients receiving ATV/r had a greater adjusted eGFR decline than those treated with DRV/r (difference -0.83 [-1.65; -0.02] mL/min/1.73 m per year; P = 0.04), but not than those receiving LPV/r; no significant difference was observed in adjusted eGFR slopes between patients receiving DRV/r and those receiving LPV/r. In the 286 patients treated with ABC and lamivudine, eGFR slopes were similar, independent of the PI.In patients receiving TDF/xTC, eGFR trajectories were small for all regimens and declined less in patients receiving DRV/r or NNRTIs than in those treated with ATV/r or LPV/r.

Renal abnormalities in a cohort of HIV-infected children and adolescents

BACKGROUND

This study aimed to identify the prevalence of renal abnormalities and the evolution of glomerular filtration rate (GFR) among human immunodeficiency virus (HIV)- infected children and adolescents followed up in an infectious disease outpatient pediatric clinic.

METHODS

We performed a cohort study of 115 children and adolescents. Outcomes of two evaluations for urinalysis, microalbuminuria/urinary creatinine ratio, urinary retinol-binding protein (uRBP) concentration, and estimated GFR (eGFR) were obtained for each patient, with an average interval of 6 months between evaluations. These changes were correlated with gender, age, race, body mass index (BMI), height-for-age (H/A) percentile, clinical and immunological classification of HIV infection, use of antiretroviral therapy (ART), HIV viral load (VL), and CD4+ T-lymphocyte count.

RESULTS

Mean patient age at the time of inclusion in the study was 12.6 ± 3.2 years; 50.4 % were male, 81.7 % had acquired immune defeciency syndrome (AIDS), 80.9 % had CD4+ < 500 cells/mm(3), and 87.8 % were on ART. Urinary changes included hematuria (11.3 %), proteinuria (7 %), and microalbuminuria (11.6 %); uRBP was present in 3.8 %; and mean eGFR was 163 ± 32 ml/min/1.73 m(2).

CONCLUSIONS

The subclinical renal abnormalities found in this study may indicate early manifestations of a broad spectrum of renal dysfunction associated with HIV and involves the decision to initiate or modify ART.

Reversibility of renal dysfunction after discontinuation of tenofovir

OBJECTIVES

The association of tenofovir (TDF) with nephrotoxicity has been a controversial issue. Few studies are published regarding the reversibility of renal dysfunction once TDF is discontinued. Studies have yet to be conducted in an urban, non-white patient population, making this one of the largest studies observing a non-white cohort. The objective of this study was to determine whether the decline in creatinine clearance (CrCL) associated with TDF use is reversible once TDF is discontinued in a non-white patient population.

METHODS

This single-center, retrospective, chart review was performed at an urban outpatient HIV clinic. Patients who had been switched from tenofovir to zidovudine or abacavir because of a decline in renal function were included. The primary endpoint was the percentage of patients who regained full, moderate, mild, or no recovery of CrCl.

RESULTS

Sixty-two patients were included. The mean age was 50 years old, 82% were black, and 66% were males with a mean baseline CrCL of 76 ml/min. Mean difference in CrCL from baseline to 12 months post-TDF was shown to be -11.34 ml/min. After a 1-year follow up period, 37.5% of patients had a full recovery of their baseline CrCL. An additional 41% of patients achieved a moderate recovery (80%-99% of baseline CrCL) and 17.9% patients had a mild recovery (50%-79% of baseline CrCL). Two patients required dialysis. The percent of patients with an undetectable HIV RNA while on a TDF-containing regimen was 67.1% compared with 74.6% on alternative ART.

CONCLUSION

Renal dysfunction caused by TDF was fully reversible in 37.5% of patients. Improvement to at least 50% of baseline was seen in 96.4% of patients. Viral suppression was not compromised when patient was switched from TDF to an alternative nucleoside reverse transcriptase inhibitor.

Human Immunodeficiency Virus as a Chronic Disease: Evaluation and Management of Nonacquired Immune Deficiency Syndrome-Defining Conditions

In the modern antiretroviral therapy (ART) era, motivated people living with human immunodeficiency virus (HIV) who have access to therapy are expected to maintain viral suppression indefinitely and to receive treatment for decades. Hence, the current clinical scenario has dramatically shifted since the early 1980s, from treatment and prevention of opportunistic infections and palliative care to a new scenario in which most HIV specialists focus on HIV primary care, ie, the follow up of stable patients, surveillance of long-term toxicities, and screening and prevention of age-related conditions. The median age of HIV-infected adults on ART is progressively increasing. By 2030, 3 of every 4 patients are expected to be aged 50 years or older in many countries, more than 80% will have at least 1 age-related disease, and approximately one third will have at least 3 age-related diseases. Contemporary care of HIV-infected patients is evolving, and questions about how we might monitor and perhaps even treat HIV-infected adults have emerged. Through key published works, this review briefly describes the most prevalent comorbidities and age-associated conditions and highlights the differential features in the HIV-infected population. We also discuss the most critical aspects to be considered in the care of patients with HIV for the management and prevention of age-associated disease.

Current status and prospects of HIV treatment

Current antiviral treatments can reduce HIV-associated morbidity, prolong survival, and prevent HIV transmission. Combination antiretroviral therapy (cART) containing preferably three active drugs from two or more classes is required for durable virologic suppression. Regimen selection is based on virologic efficacy, potential for adverse effects, pill burden and dosing frequency, drug-drug interaction potential, resistance test results, comorbid conditions, social status, and cost. With prolonged virologic suppression, improved clinical outcomes, and longer survival, patients will be exposed to antiretroviral agents for decades. Therefore, maximizing the safety and tolerability of cART is a high priority. Emergence of resistance and/or lack of tolerability in individual patients require availability of a range of treatment options. Development of new drugs is focused on improving safety (e.g. tenofovir alafenamide) and/or resistance profile (e.g. doravirine) within the existing drug classes, combination therapies with improved adherence (e.g. single-tablet regimens), novel mechanisms of action (e.g. attachment inhibitors, maturation inhibitors, broadly neutralizing antibodies), and treatment simplification with infrequent dosing (e.g. long-acting injectables). In parallel with cART innovations, research and development efforts focused on agents that target persistent HIV reservoirs may lead to prolonged drug-free remission and HIV cure.

Dual Therapy Treatment Strategies for the Management of Patients Infected with HIV: A Systematic Review of Current Evidence in ARV-Naive or ARV-Experienced, Virologically Suppressed Patients

Objective

We reviewed the current literature regarding antiretroviral (ARV)-sparing therapy strategies to determine whether these novel regimens can be considered appropriate alternatives to standard regimens for the initial treatment of ARV-naive patients or as switch therapy for those patients with virologically suppressed HIV infection.

Methods

A search for studies related to HIV dual therapy published from January 2000 through April 2014 was performed using Biosis, Derwent Drug File, Embase, International Pharmaceutical Abstracts, Medline, Pascal, SciSearch, and TOXNET databases; seven major trial registries, and the abstracts of major conferences. Using predetermined criteria for inclusion, an expert review committee critically reviewed and qualitatively evaluated all identified trials for efficacy and safety results and potential limitations.

Results

Sixteen studies of dual therapy regimens were critiqued for the ARV-naive population. Studies of a protease inhibitor/ritonavir in combination with the integrase inhibitor raltegravir or the nucleoside reverse transcriptase inhibitor lamivudine provided the most definitive evidence supporting a role for dual therapy. In particular, lopinavir/ritonavir or darunavir/ritonavir combined with raltegravir and lopinavir/ritonavir combined with lamivudine demonstrated noninferiority to standard of care triple therapy after 48 weeks of treatment. Thirteen trials were critiqued in ARV-experienced, virologically suppressed patients. The virologic efficacy outcomes were mixed. Although overall data regarding toxicity are limited, when compared with standard triple therapy, certain dual therapy regimens may offer advantages in renal function, bone mineral density, and limb fat changes; however, some dual combinations may elevate lipid or bilirubin levels.

Conclusions

The potential benefits of dual therapy regimens include reduced toxicity, improved tolerability and adherence, and reduced cost. Although the data reviewed here provide valuable insights into the effectiveness and tolerability of dual therapy regimens, it remains unclear whether these potential benefits can be maintained long-term. Appropriately powered studies with longer follow-up periods are needed to more definitively assess potential toxicity reduction advantages with dual therapy.

Updates on the Pharmacologic Treatment of Individuals with Human Immunodeficiency Virus

Human immunodeficiency virus has been affecting the human population for more than 30 years. During this time period, more effective, safe, simple, and tolerable pharmacologic agents have been developed. To date, there are 26 antiretroviral agents available that are used either as a single agent or a coformulation in an antiretroviral regimen. The goal of these medications is to achieve viral suppression in individuals infected with human immunodeficiency virus. Evidence continues to support the most effective combinations. It is important that clinicians are knowledgeable of updates so as to provide the best possible medical regimen for this population.

Tenofovir is associated with increased tubular proteinuria and asymptomatic renal tubular dysfunction in Ghana

BACKGROUND

HIV infection is associated with increased risk of renal dysfunction, including tubular dysfunction (TD) related to antiretroviral therapy (ART). Tenofovir disoproxil fumarate (TDF) is becoming available for ART in sub-Saharan Africa, although data on its long-term safety there is limited. We aimed to study the prevalence of HIV-associated renal dysfunction in Ghana and explore associations between proteinuria or TD and potential risk factors, including TDF use.

METHODS

A single-centre cross-sectional observational study of patients taking ART was undertaken. Creatinine clearance (CrCl) was calculated and proteinuria detected with dipsticks. Spot urinary albumin and protein:creatinine ratios (uACR/uPCR) were measured and further evidence of TD (defined as having two or more characteristic features) sought. Logistic regression analysis identified factors associated with proteinuria or TD.

RESULTS

In 330 patients, of whom 101 were taking TDF (median 20 months), the prevalence of CrCl < 60 ml/min/1.73 m(2), dipstick proteinuria and TD was 7 %, 37 % and 15 %. Factors associated with proteinuria were baseline CD4-count [aOR 0.86/100 cell increment (95 % CI, 0.74-0.99)] and TDF use [aOR 2.74 (95 % CI, 1.38-5.43)]. The only factor associated with TD was TDF use [aOR 3.43 (95 % CI, 1.10-10.69)]. In a subset with uPCR measurements, uPCRs were significantly higher in patients taking TDF than those on other drugs (10.8 vs. 5.7 mg/mmol, p < 0.001), and urinary albuin:protein ratios significantly lower (0.24 vs. 0.58, p < 0.001).

CONCLUSIONS

Both proteinuria and TD are common and associated with TDF use in Ghana. Further longitudinal studies to determine whether proteinuria, TD or TDF use are linked to progressive decline in renal function or other adverse outcomes are needed in Africa.

HIV and the kidney in the acute medical unit

Acute kidney injury (AKI) is encountered commonly in HIV-positive patients admitted to the acute medical unit. The spectrum of AKI has changed in the era of combination anti-retroviral therapy, and now includes adverse effects of commonly used anti-retroviral drugs in addition to traditional precipitants such as severe sepsis or exposure to nephrotoxic antimicrobials. An accurate diagnosis requires careful integration of clinical data including volume status, history of potentially nephrotoxic exposures and consideration of immuno-virological status. This article provides an overview of common causes of AKI in HIV and presents a framework by which the acute care physician may approach the finding of an elevated serum creatinine in a patient with HIV.

Drug Transporter Genetic Variants Are Not Associated with TDF-Related Renal Dysfunction in Patients with HIV-1 Infection: A Pharmacogenetic Study

Objective

To investigate whether single nucleotide polymorphisms (SNP) of drug transporter proteins for TDF is a risk factor for TDF-related renal function decrement.

Methods

This study investigated the association between 3 SNPs (ABCC2–24, 1249, and ABCB1 2677), which are shown to be associated with TDF-induced tubulopathy, and clinically important renal outcomes (>10ml/min/1.73m² decrement in eGFR relative to baseline, >25% decrement in eGFR, and eGFR <60ml/min/1.73m²) in 703 HIV-1-infected Japanese patients who initiated TDF-containing antiretroviral therapy (ART). Genotyping was performed by allelic discrimination using TaqMan 5’-nuclease assays.

Results

95% of the study patients were males and 66% were treatment-naïve, with median CD4 count of 249/μl, median baseline eGFR of 96ml/min/1.73m² (IQR 84.6–109.2), and median exposure to TDF of 3.66 years (IQR 1.93–5.59). The frequencies of genotypes at -24, 1249 of ABCC2, and 2677 of ABCB1 were neither different between patients with decrement in eGFR of >10ml/min/1.73m² and those without such decrement (ABCC2: -24, p = 0.53, 1249, p = 0.68; ABCB1: 2677, p = 0.74), nor between those without and with the other two renal outcomes (>25% decrement: ABCC2: -24, p = 0.83, 1249, p = 0.97, ABCB1: 2677, p = 0.40; eGFR <60ml/min/1.73m²: ABCC2: -24, p = 0.51, 1249, p = 0.81, ABCB1: 2677, p = 0.94). Logistic regression analysis showed that the risk genotype of the three SNPs were not associated with any of the three renal outcomes, respectively. Logistic regression model that applied either dominant, recessive, or additive model yielded the same results.

Conclusions

SNPs of the drug transporters for TDF are not associated with clinically important renal outcomes in patients who initiated TDF-containing ART.

Proteinuria is common among HIV patients: what are we missing?

OBJECTIVES

HIV-related renal diseases are the leading causes of chronic kidney diseases worldwide. The present study aimed to investigate the prevalence of pathological proteinuria and its risk factors among HIV patients.

METHODS

A review of the medical records of 666 HIV-infected individuals aged 18 years or older in an urban HIV/AIDS clinic based in Porto Alegre in southern Brazil. Overt proteinuria was defined as a protein-to-creatinine ratio greater than 150 mg/g according to Kidney Disease: Improving Global Outcomes.

RESULTS

The prevalence of pathological proteinuria in the present study cohort was 20%. Characteristics associated with pathological proteinuria after univariate analysis included alcohol abuse, hepatitis C virus coinfection, the occurrence of diabetes and therapy including tenofovir. Adjusted residuals analysis indicated an association between pathological proteinuria and both a CD4 lymphocyte count below 200 cells/mm3 and a viral load higher than 1000 copies/mL. Additionally, an absence of pathological proteinuria was associated with a CD4 lymphocyte count higher than 500 cells/mm3. After adjustment for variables with p<0.2 in the univariate analysis using a Poisson regression model, tenofovir-containing regimens and a CD4 lymphocyte count below 200 cells/mm3 were significantly associated with pathological proteinuria.

CONCLUSION

The risk of chronic kidney diseases in this large contemporary cohort of HIV-infected individuals appeared to be attributable to a combination of HIV-related risk factors. In addition to the traditional risk factors cited in the literature, both regimens containing tenofovir and HIV disease severity seem to be associated with chronic kidney diseases in patients with HIV. Assessment of proteinuria constitutes a novel method for chronic kidney disease staging in HIV-infected individuals and may be effectively used to stratify the risk of progression to end-stage renal disease.

Clinical evolution of chronic renal patients with HIV infection in replacement therapy

Patients on renal replacement therapy (RRT) infected with the human immunodeficiency virus (HIV) are a special group with growing interest. In order to study the epidemiological data of HIV+ patients on RRT in Spain, we collected individual information from 2004-2011 (period of use of highly active antiretroviral therapy [HAART] in the Autonomous Communities of Andalusia, Aragon, Asturias, Catalonia, Valencia, Castilla la Mancha, Castilla León, Galicia, Madrid, La Rioja and the Basque Country, comprising 85% of the Spanish population. A total of 271 incident and 209 prevalent patients were analysed. They were compared with the remaining patients on RRT during the same period. The annual incidence was 0.8 patients per one million inhabitants, with a significant increase during the follow-up period. The proportion of prevalent HIV+ patients was 5.1 per 1,000 patients on RRT (95% confidence interval [CI] 4.4-5.8. Although glomerular diseases constituted the majority of cases (42%), diabetic nephropathy was the cause in 14% of patients. The nation-wide totals for these percentages were 13 and 25%, respectively. Compared to the total of patients in treatment, the risk of death was significantly higher in the HIV+ group: hazard ratio (HR) adjusted for age, sex and diabetes was 2.26 (95% CI 1.74 - 2.91). Hepatitis C coinfection increased the risk of death in the HIV+ group (HR 1.77; 95% CI 1.10 - 2.85). The probability of kidney transplantation in HIV+ was only 17% after 7 years, comparing with total RTT patients (HR 0.15; 95% CI: 0.10-0.24). Despite the use of HAART, the incidence of HIV+ patients on dialysis has increased; their mortality still exceeds non-HIV patients, and they have a very low rate of transplantation. It is necessary to further our knowledge of this disease in order to improve results.

Improvement in renal function and bone mineral density after a switch from tenofovir/emtricitabine plus ritonavir-boosted protease inhibitor to raltegravir plus nevirapine: a pilot study

BACKGROUND

The antiretroviral regimens including tenofovir and a ritonavir-boosted protease inhibitor (r/PI) have been associated with a reduced bone mineral density (BMD), increased bone turnover markers and renal tubular dysfunction.

METHODS

An observational, prospective study was performed including HIV-1-infected, virologically suppressed patients treated with tenofovir/emtricitabine plus an r/PI for at least 12 months who switched to raltegravir plus nevirapine. The primary end point was changes after 48 weeks in estimated glomerular filtration rate (eGFR), prevalence of tubular dysfunction, BMD and concentration of two serum markers of bone turnover: collagen type-1 cross-linked C-telopeptide (CTX) and bone-specific alkaline phosphatase (BAP).

RESULTS

A total of 46 patients were enrolled: 78% were male, 96% were Caucasian, the mean age was 45 years and the mean CD4(+) T-lymphocyte count was 681 cells/mm(3). A renal impairment was present in 72% of patients and was the main reason for the switch. After 48 weeks, prevalence of proximal tubular dysfunction decreased significantly (-72%; P<0.001), whereas the mean value of eGFR did not change significantly. At the same time, after 48 weeks a significant increase in both lumbar spine and total hip BMD, T-score and Z-score was reported (+11.5% in lumbar spine T-score; P<0.001), and there was a significant reduction in both CTX and BAP mean serum concentrations (-15% and -13%, respectively; P<0.001). Two (4.3%) patients had virological failure due to suboptimal adherence and one (2.2%) subject discontinued treatment due to a skin rash.

CONCLUSIONS

Switching virologically suppressed patients from tenofovir/emtricitabine plus one r/PI to raltegravir plus nevirapine after 48 weeks significantly improved proximal tubular function, increased BMD and reduced serum markers of bone turnover.

Full-length soluble urokinase plasminogen activator receptor down-modulates nephrin expression in podocytes

Increased plasma level of soluble urokinase-type plasminogen activator receptor (suPAR) was associated recently with focal segmental glomerulosclerosis (FSGS). In addition, different clinical studies observed increased concentration of suPAR in various glomerular diseases and in other human pathologies with nephrotic syndromes such as HIV and Hantavirus infection, diabetes and cardiovascular disorders. Here, we show that suPAR induces nephrin down-modulation in human podocytes. This phenomenon is mediated only by full-length suPAR, is time-and dose-dependent and is associated with the suppression of Wilms’ tumor 1 (WT-1) transcription factor expression. Moreover, an antagonist of αvβ3 integrin RGDfv blocked suPAR-induced suppression of nephrin. These in vitro data were confirmed in an in vivo uPAR knock out Plaur^−/− mice model by demonstrating that the infusion of suPAR inhibits expression of nephrin and WT-1 in podocytes and induces proteinuria. This study unveiled that interaction of full-length suPAR with αvβ3 integrin expressed on podocytes results in down-modulation of nephrin that may affect kidney functionality in different human pathologies characterized by increased concentration of suPAR.

Renal tubular disease in the era of combination antiretroviral therapy

OBJECTIVES

To describe the spectrum of renal tubular disease (RTD) in HIV-positive patients and its association with exposure to antiretroviral therapy (ART).

DESIGN

Review of 265 consecutive renal biopsies from HIV-positive patients attending eight clinics in the United Kingdom between 2000 and 2012.

METHODS

We described the clinical characteristics of patients with RTD and compared current/recent exposure (at the time of, or up to 3 months prior to the date of biopsy) to potentially nephrotoxic ART [tenofovir (TDF), atazanavir (ATV), indinavir (IDV) and lopinavir/ritonavir (LPV/r)]. We also analysed the incidence of RTD in the UK CHIC cohort. Kruskall-Wallis, analysis of variance and Fisher's exact tests were used to evaluate between-group differences.

RESULTS

Of the 60 RTD cases, 54 (90%) were included in the analyses. RTD comprised of three distinct patterns: acute tubular injury (ATI, n = 22), tubulo-interstitial nephritis (TIN, n = 20) and interstitial fibrosis and tubular atrophy (IFTA, n = 12). Compared with TIN and IFTA, ATI cases were less likely to be of black ethnicity (10 vs. 42-55%; P = 0.006), more likely to be on ART (100 vs. 55-68%; P = 0.001), with HIV-RNA below 200 copies/ml (100 vs. 54-58%; P < 0.001), and more likely to have current/recent exposure to TDF (P < 0.001). We did not find evidence for an association between exposure to TDF, ATV/r or LPV/r and either TIN or IFTA.

CONCLUSION

RTD was present in approximately 20% of renal biopsies and comprised three distinct injury patterns with considerable clinical overlap. ATI was associated with TDF exposure, although the overall incidence of biopsy-defined ATI was low.

Albuminuria Is Associated with Traditional Cardiovascular Risk Factors and Viral Load in HIV-Infected Patients in Rural South Africa

Context

As life expectancy improves among Human Immunodeficiency Virus (HIV) patients, renal and cardiovascular diseases are increasingly prevalent in this population. Renal and cardiovascular disease are mutual risk factors and are characterized by albuminuria. Understanding the interactions between HIV, cardiovascular risk factors and renal disease is the first step in tackling this new therapeutic frontier in HIV.

Methods

In a rural primary health care centre, 903 HIV-infected adult patients were randomly selected and data on HIV-infection and cardiovascular risk factors were collected. Glomerular filtration rate (eGFR) was estimated. Albuminuria was defined as an Albumin-Creatinine-Ratio above 30 mg/g. Multivariate logistic regression analysis was used to analyse albuminuria and demographic, clinical and HIV-associated variables.

Results

The study population consisted of 903 HIV-infected patients, with a median age of 40 years (Inter-Quartile Range (IQR) 34–48 years), and included 625 (69%) women. The median duration since HIV diagnosis was 26 months (IQR 12–58 months) and 787 (87%) received antiretroviral therapy. Thirty-six (4%) of the subjects were shown to have diabetes and 205 (23%) hypertension. In the cohort, 21% had albuminuria and 2% an eGFR <60 mL/min/1.73m². Albuminuria was associated with hypertension (adjusted odds ratio (aOR) 1.59; 95% confidence interval (CI) 1.05–2.41; p<0.05), total cholesterol (aOR 1.31; 95% CI 1.11–1.54; p<0.05), eGFR (aOR 0.98; 95% CI 0.97–0.99; p<0.001) and detectable viral load (aOR 2.74; 95% CI 1.56–4.79; p<0.001). Hypertension was undertreated: 78% were not receiving treatment, while another 11% were inadequately treated. No patients were receiving lipid-lowering medication.

Conclusion

Glomerular filtration rate was well conserved, while albuminuria was common amongst HIV-infected patients in rural South Africa. Both cardiovascular and HIV-specific variables were associated with albuminuria. Improved cardiovascular risk prevention as well as adequate virus suppression might be the key to escape the vicious circle of renal failure and cardiovascular disease and improve the long-term prognosis of HIV-infected patients.

Future challenges for clinical care of an ageing population infected with HIV: a modelling study

BACKGROUND

The population infected with HIV is getting older and these people will increasingly develop age-related non-communicable diseases (NCDs). We aimed to quantify the scale of the change and the implications for HIV care in the Netherlands in the future.

METHODS

We constructed an individual-based model of the ageing HIV-infected population, which followed patients on HIV treatment as they age, develop NCDs-including cardiovascular disease (hypertension, hypercholesterolaemia, myocardial infarctions, and strokes), diabetes, chronic kidney disease, osteoporosis, and non-AIDS malignancies-and start co-medication for these diseases. The model was parameterised by use of data for 10 278 patients from the national Dutch ATHENA cohort between 1996 and 2010. We made projections up to 2030.

FINDINGS

Our model suggests that the median age of HIV-infected patients on combination antiretroviral therapy (ART) will increase from 43·9 years in 2010 to 56·6 in 2030, with the proportion of HIV-infected patients aged 50 years or older increasing from 28% in 2010 to 73% in 2030. In 2030, we predict that 84% of HIV-infected patients will have at least one NCD, up from 29% in 2010, with 28% of HIV-infected patients in 2030 having three or more NCDs. 54% of HIV-infected patients will be prescribed co-medications in 2030, compared with 13% in 2010, with 20% taking three or more co-medications. Most of this change will be driven by increasing prevalence of cardiovascular disease and associated drugs. Because of contraindications and drug-drug interactions, in 2030, 40% of patients could have complications with the currently recommended first-line HIV regimens.

INTERPRETATION

The profile of patients in the Netherlands infected with HIV is changing, with increasing numbers of older patients with multiple morbidities. These changes mean that, in the near future, HIV care will increasingly need to draw on a wide range of medical disciplines, in addition to evidence-based screening and monitoring protocols to ensure continued high-quality care. These findings are based on a large dataset of HIV-infected patients in the Netherlands, but we believe that the overall patterns will be repeated elsewhere in Europe and North America. The implications of such a trend for care of HIV-infected patients in high-burden countries in Africa could present a particular challenge.

FUNDING

Medical Research Council, Bill & Melinda Gates Foundation, Rush Foundation, and Netherlands Ministry of Health, Welfare and Sport.

Future challenges for clinical care of an ageing population infected with HIV: a modelling study

BACKGROUND

The population infected with HIV is getting older and these people will increasingly develop age-related non-communicable diseases (NCDs). We aimed to quantify the scale of the change and the implications for HIV care in the Netherlands in the future.

METHODS

We constructed an individual-based model of the ageing HIV-infected population, which followed patients on HIV treatment as they age, develop NCDs-including cardiovascular disease (hypertension, hypercholesterolaemia, myocardial infarctions, and strokes), diabetes, chronic kidney disease, osteoporosis, and non-AIDS malignancies-and start co-medication for these diseases. The model was parameterised by use of data for 10 278 patients from the national Dutch ATHENA cohort between 1996 and 2010. We made projections up to 2030.

FINDINGS

Our model suggests that the median age of HIV-infected patients on combination antiretroviral therapy (ART) will increase from 43·9 years in 2010 to 56·6 in 2030, with the proportion of HIV-infected patients aged 50 years or older increasing from 28% in 2010 to 73% in 2030. In 2030, we predict that 84% of HIV-infected patients will have at least one NCD, up from 29% in 2010, with 28% of HIV-infected patients in 2030 having three or more NCDs. 54% of HIV-infected patients will be prescribed co-medications in 2030, compared with 13% in 2010, with 20% taking three or more co-medications. Most of this change will be driven by increasing prevalence of cardiovascular disease and associated drugs. Because of contraindications and drug-drug interactions, in 2030, 40% of patients could have complications with the currently recommended first-line HIV regimens.

INTERPRETATION

The profile of patients in the Netherlands infected with HIV is changing, with increasing numbers of older patients with multiple morbidities. These changes mean that, in the near future, HIV care will increasingly need to draw on a wide range of medical disciplines, in addition to evidence-based screening and monitoring protocols to ensure continued high-quality care. These findings are based on a large dataset of HIV-infected patients in the Netherlands, but we believe that the overall patterns will be repeated elsewhere in Europe and North America. The implications of such a trend for care of HIV-infected patients in high-burden countries in Africa could present a particular challenge.

FUNDING

Medical Research Council, Bill & Melinda Gates Foundation, Rush Foundation, and Netherlands Ministry of Health, Welfare and Sport.

Tenofovir alafenamide versus tenofovir disoproxil fumarate, coformulated with elvitegravir, cobicistat, and emtricitabine, for initial treatment of HIV-1 infection: two randomised, double-blind, phase 3, non-inferiority trials

BACKGROUND

Tenofovir disoproxil fumarate can cause renal and bone toxic effects related to high plasma tenofovir concentrations. Tenofovir alafenamide is a novel tenofovir prodrug with a 90% reduction in plasma tenofovir concentrations. Tenofovir alafenamide-containing regimens can have improved renal and bone safety compared with tenofovir disoproxil fumarate-containing regimens.

METHODS

In these two controlled, double-blind phase 3 studies, we recruited treatment-naive HIV-infected patients with an estimated creatinine clearance of 50 mL per min or higher from 178 outpatient centres in 16 countries. Patients were randomly assigned (1:1) to receive once-daily oral tablets containing 150 mg elvitegravir, 150 mg cobicistat, 200 mg emtricitabine, and 10 mg tenofovir alafenamide (E/C/F/tenofovir alafenamide) or 300 mg tenofovir disoproxil fumarate (E/C/F/tenofovir disoproxil fumarate) with matching placebo. Randomisation was done by a computer-generated allocation sequence (block size 4) and was stratified by HIV-1 RNA, CD4 count, and region (USA or ex-USA). Investigators, patients, study staff, and those assessing outcomes were masked to treatment group. All participants who received one dose of study drug were included in the primary intention-to-treat efficacy and safety analyses. The main outcomes were the proportion of patients with plasma HIV-1 RNA less than 50 copies per mL at week 48 as defined by the the US Food and Drug Adminstration (FDA) snapshot algorithm (pre-specified non-inferiority margin of 12%) and pre-specified renal and bone endpoints at 48 weeks. These studies are registered with ClinicalTrials.gov, numbers NCT01780506 and NCT01797445.

FINDINGS

We recruited patients from Jan 22, 2013, to Nov 4, 2013 (2175 screened and 1744 randomly assigned), and gave treatment to 1733 patients (866 given E/C/F/tenofovir alafenamide and 867 given E/C/F/tenofovir disoproxil fumarate). E/C/F/tenofovir alafenamide was non-inferior to E/C/F/tenofovir disoproxil fumarate, with 800 (92%) of 866 patients in the tenofovir alafenamide group and 784 (90%) of 867 patients in the tenofovir disoproxil fumarate group having plasma HIV-1 RNA less than 50 copies per mL (adjusted difference 2·0%, 95% CI -0·7 to 4·7). Patients given E/C/F/tenofovir alafenamide had significantly smaller mean serum creatinine increases than those given E/C/F/tenofovir disoproxil fumarate (0·08 vs 0·12 mg/dL; p<0·0001), significantly less proteinuria (median % change -3 vs 20; p<0·0001), and a significantly smaller decrease in bone mineral density at spine (mean % change -1·30 vs -2·86; p<0·0001) and hip (-0·66 vs -2·95; p<0·0001) at 48 weeks.

INTERPRETATION

Through 48 weeks, more than 90% of patients given E/C/F/tenofovir alafenamide or E/C/F/tenofovir disoproxil fumarate had virological success. Renal and bone effects were significantly reduced in patients given E/C/F/tenofovir alafenamide. Although these studies do not have the power to assess clinical safety events such as renal failure and fractures, our data suggest that E/C/F/tenofovir alafenamide will have a favourable long-term renal and bone safety profile.

FUNDING

Gilead Sciences.

Dual treatment with atazanavir-ritonavir plus lamivudine versus triple treatment with atazanavir-ritonavir plus two nucleos(t)ides in virologically stable patients with HIV-1 (SALT): 48 week results from a randomised, open-label, non-inferiority trial

BACKGROUND

Problems associated with lifelong antiretroviral therapy, such as need for strict adherence, drug-related toxic effects, difficulties with treatment schedules, and cost, mean that simplification strategies should be sought. We aimed to explore the efficacy and safety of dual treatment with atazanavir-ritonavir plus lamivudine as an option to switch to from standard combination antiretroviral therapy in patients with an HIV-1 infection who are virologically suppressed.

METHODS

In this randomised, open-label, non-inferiority trial, we recruited patients aged 18 years and older with chronic HIV-1 infection and no previous treatment failure or resistance, and with HIV-1 RNA of less than 50 copies per mL for at least 6 months, negative hepatitis B virus surface antigen, and good general health, from 30 hospitals in Spain. Exclusion criteria were switch in antiretroviral therapy during the previous 4 months, previous virological failure, pregnancy or breastfeeding, Gilbert's syndrome, use of contraindicated drugs, grade 4 laboratory abnormalities, and previous intolerance to any of the study drugs. We randomly assigned patients (1:1; stratified by active hepatitis C virus infection and previous treatment; computer-generated random number sequence) to dual treatment with oral atazanavir (300 mg once daily) and ritonavir (100 mg once daily) plus lamivudine (300 mg once daily) or triple treatment with oral atazanavir (300 mg once daily) and ritonavir (100 mg once daily) plus two nucleos(t)ide reverse transcriptase inhibitors at the discretion of the investigators. The primary endpoint was virological response, defined as HIV-1 RNA of less than 50 copies per mL at week 48, in the per-protocol population, with a non-inferiority margin of 12%. We included patients who received at least one dose of the study drug in the safety analysis. This study is registered at ClinicalTrials.gov, number NCT01307488.

FINDINGS

Between Sept 29, 2011, and May 2, 2013, we randomly assigned 286 patients (143 [50%] to each group). At week 48 in the per-protocol population, 112 (84%) of 133 patients had virological response in the dual-treatment group versus 105 (78%) of 135 in the triple-treatment group (difference 6% [95% CI -5 to 16%), showing non-inferiority at the prespecified level. 14 (5%) patients developed severe adverse events (dual treatment six [4%]; triple treatment eight [6%]), none of which we deemed related to the study drug. Grade 3-4 adverse events were similar between groups (dual treatment 77 [55%] of 140; triple treatment 78 [55%] of 141). Treatment discontinuations were less frequent in the dual-treatment group (three [2%]) than in the triple-treatment group (ten [7%]; p=0·047).

INTERPRETATION

In our trial, dual treatment was effective, safe, and non-inferior to triple treatment in patients with an HIV-1 infection who are virologically suppressed who switch antiretroviral therapy because of toxic effects, intolerance, or simplification. This combination has the potential to suppress some of the long-term toxic effects associated with nucleos(t)ide reverse transcriptase inhibitors, preserve future treatment options, and reduce the cost of antiretroviral therapy.

FUNDING

Bristol Myers-Squibb and Fundación SEIMC-GESIDA.

Relationships between Serum Levels of Atazanavir and Renal Toxicity or Lithiasis

The main aim of this study is to describe the relationship between serum levels of atazanavir, renal toxicity, and lithiasis. This is a prospective observational study of patients being treated with atazanavir (ATV) at Son Espases Teaching Hospital, Palma de Mallorca, between 2011 and 2013. The study includes 98 patients. Sixteen were found to have a history of urolithiasis. During a median monitoring period of 23 months, nine patients suffered renal colic, in three of whom ATV crystals were evidenced in urine. Cumulative incidence of renal colic was 9.2 per 100 patients. The variables related to having renal colic were the presence of alkaline urine pH and lower basal creatinine clearance. The mean serum level of ATV was slightly higher in patients with renal colic-1,303 μg/L versus 1,161 μg/L-but did not reach statistical significance. Neither were any significant differences detected by analysing the levels according to the timetable for ATV dosage. Cumulative incidence of renal colic was high in patients being treated with ATV, in 33% of whom the presence of ATV crystals was evidenced in urine. We were unable to demonstrate a relationship between ATV serum levels and renal colic or progression towards renal failure.

Monitoring of kidney function in HIV-positive patients

HIV-positive patients are at increased risk of developing chronic kidney disease. Although guidelines recommend regular monitoring of renal function in individuals living with HIV, the optimal frequency remains to be defined. In this review, we discuss the renal syndromes that may be identified at an earlier stage via routine assessment of kidney function, and provide guidance in terms of the frequency of monitoring, the most useful tests to perform, and their clinical significance. Specifically, we address whether annual monitoring of kidney function is appropriate for the majority of HIV-positive patients.

Beginning antiretroviral therapy for patients with HIV

In this article, we review the options for initial antiretroviral therapy, including the data from clinical trials to support these choices and the factors to consider in selection of a regimen to best fit each patient.

Relationships between renal parameters and serum and urine markers of inflammation in those with and without HIV infection

We sought to determine the relationships among intrarenal and systemic inflammation and renal disease in HIV. We compared paired serum and urinary levels (normalized to urine creatinine) of monocyte chemotactic protein-1 (MCP-1), regulated on activation normal T cell expressed and secreted (RANTES), interferon-γ-induced protein-10 (IP-10), interleukin-8 (IL-8), and β2-microglobulin (B2M) between two groups of HIV-infected subjects not receiving antiretroviral therapy (ART) [A: not expecting to initiate ART immediately due to having CD4 cell counts ≥350/μl, N=26; B: about to initiate ART, N=19], a group of HIV-infected subjects receiving virologically suppressive antiretroviral therapy [C, N=30], and a group of HIV-uninfected, healthy volunteers [D, N=45]. We then correlated these inflammatory biomarker levels with urine protein/creatinine ratios (uPCR), urine albumin/creatinine ratios (uACR), and estimated glomerular filtration rates (eGFR). Urine inflammatory biomarker levels were highest in Group B. When combining all four study groups, statistically significant positive correlations included uPCR with urine IL-8, urine MCP-1, urine IP-10, and serum IP-10 and uACR with urine IL-8, urine B2M, serum IP-10, and serum B2M. eGFR was statistically significantly negatively correlated with serum MCP-1 and serum B2M. Paired serum and urine levels of IP-10 and B2M (but not IL-8, RANTES, or MCP-1) were significantly correlated with each other in the overall group. The levels of urine inflammatory markers tested differed by HIV status and use of virologically suppressive ART. These urine and serum inflammatory markers were differentially correlated with uPCR, uACR, and eGFR, suggesting that different intrarenal and systemic inflammatory pathways may contribute to different measures of nephropathy.

Atazanavir nephrotoxicity

Atazanavir is commonly used as one of the key drugs in combination antiretroviral therapy for human immunodeficiency virus (HIV). However, atazanavir has the potential to yield its crystalline precipitation in urine and renal interstitial tissues, leading to crystalluria, urolithiasis, acute kidney injury (AKI) or chronic kidney disease (CKD). In epidemiological studies, atazanavir/ritonavir alone or in combination with tenofovir has been associated with increased risk of progression to CKD. However, renal biopsies were not provided in these studies. Case reports showing an association between atazanavir use and tubulointerstitial nephritis among HIV-infected individuals provide clues as to the potential causes of atazanavir nephrotoxicity. We now review atazanavir-related kidney disease including urolithiasis, renal dysfunction and interstitial nephritis and illustrate the review with a further case of atazanavir-associated kidney injury with sequential renal biopsies. There are two forms of atazanavir-associated tubulointerstitial nephritis: acute tubulointerstitial nephritis that may develop AKI rapidly (in weeks) after initiation of atazanavir, and chronic tubulointerstitial nephritis that may develop progressive CKD slowly (in years) with granuloma and intrarenal precipitation of atazanavir crystals as well as crystalluria. Caution should be exercised when prescribing atazanavir to patients at high risk of CKD, and therapy should be reevaluated if renal function deteriorates, especially associated with crystalluria and hematuria.

Individualizing pharmacotherapy in patients with renal impairment: the validity of the Modification of Diet in Renal Disease formula in specific patient populations with a glomerular filtration rate below 60 ml/min. A systematic review

Background

The Modification of Diet in Renal Disease (MDRD) formula is widely used in clinical practice to assess the correct drug dose. This formula is based on serum creatinine levels which might be influenced by chronic diseases itself or the effects of the chronic diseases. We conducted a systematic review to determine the validity of the MDRD formula in specific patient populations with renal impairment: elderly, hospitalized and obese patients, patients with cardiovascular disease, cancer, chronic respiratory diseases, diabetes mellitus, liver cirrhosis and human immunodeficiency virus.

Methods and Findings

We searched for articles in Pubmed published from January 1999 through January 2014. Selection criteria were (1) patients with a glomerular filtration rate (GFR) < 60 ml/min (/1.73m²), (2) MDRD formula compared with a gold standard and (3) statistical analysis focused on bias, precision and/or accuracy. Data extraction was done by the first author and checked by a second author. A bias of 20% or less, a precision of 30% or less and an accuracy expressed as P₃₀% of 80% or higher were indicators of the validity of the MDRD formula. In total we included 27 studies. The number of patients included ranged from 8 to 1831. The gold standard and measurement method used varied across the studies. For none of the specific patient populations the studies provided sufficient evidence of validity of the MDRD formula regarding the three parameters. For patients with diabetes mellitus and liver cirrhosis, hospitalized patients and elderly with moderate to severe renal impairment we concluded that the MDRD formula is not valid. Limitations of the review are the lack of considering the method of measuring serum creatinine levels and the type of gold standard used.

Conclusion

In several specific patient populations with renal impairment the use of the MDRD formula is not valid or has uncertain validity.

Development and validation of a risk score for chronic kidney disease in HIV infection using prospective cohort data from the D:A:D study

BACKGROUND

Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice.

METHODS AND FINDINGS

A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with ≥3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR ≤ 60 ml/min/1.73 m2. Poisson regression was used to develop a risk score, externally validated on two independent cohorts. In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1:393 chance of developing CKD in the next 5 y in the low risk group (risk score < 0, 33 events), rising to 1:47 and 1:6 in the medium (risk score 0-4, 103 events) and high risk groups (risk score ≥ 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria.

CONCLUSIONS

Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.

Switching from tenofovir containing regimens to boosted protease inhibitor monotherapy: Impact on renal function

OBJECTIVE

To evaluate the effect on creatinine clearance (CG-CrCl, Cockcroft-Gault equation) of switching to boosted protease inhibitor (PI) monotherapy in patients receiving a triple drug antiretroviral regimen containing TDF.

METHODS

All patients who had received a TDF-containing regimen for at least one year and had been switched to PI monotherapy were included. A rapid decrease in CG-CrCl during exposure to TDF was defined as a decrease in CG-CrCl at least five times higher than the expected due to age (0.4ml/min/year by the years of exposure to TDF). In this subgroup of patients, we considered improvement if the last value of CG-CrCl on PI monotherapy was 10% higher than the last value of CG-CrCl before switching to PI monotherapy. A multivariate logistic regression was constructed to identify factors associated to renal improvement after switching to bPI monotherapy.

RESULTS

64 patients included. The median (IQR) annual change in CG-CrCl during PI monotherapy was significantly lower than the median (IQR) annual change while exposed to TDF [-0.9 (-4.7 to +2.8) ml/min vs. -4 (-8 to -1) ml/min, p=0.001]. 44 patients experienced a rapid decline during TDF exposition. After switch to PI monotherapy, 15/44 (34%, 95% CI: 21-50%) had an improved CG-CrCl and 16/44 (36%, CI 23-52%) experienced a further decline in CG-CrCl. The only variable associated to CG-CrCl improvement was a more rapid CG-CrCl decline in the last year of exposure to TDF.

CONCLUSION

Switching to PI monotherapy partially reversed CG-CrCl decrease associated to TDF use, especially in patients with a more rapid decline while receiving TDF.

Changes in glomerular kidney function among HIV-1-uninfected men and women receiving emtricitabine-tenofovir disoproxil fumarate preexposure prophylaxis: a randomized clinical trial

IMPORTANCE

Tenofovir disoproxil fumarate (TDF) use has been associated with declines in the estimated glomerular filtration rate (eGFR) when used as part of antiretroviral treatment by persons with human immunodeficiency virus (HIV) type 1, but limited data are available for risk when used as preexposure prophylaxis (PrEP) for HIV-1 prevention.

OBJECTIVE

To determine whether TDF-based PrEP causes eGFR decline in HIV-1-uninfected adults.

DESIGN, SETTING, AND PARTICIPANTS

A per-protocol safety analysis of changes in eGFR in the Partners PrEP Study, a randomized, placebo-controlled trial of daily oral TDF and emtricitabine (FTC)-TDF PrEP among heterosexual HIV-1-uninfected members of serodiscordant couples in Kenya and Uganda. The trial was conducted from 2008 to 2012.

MAIN OUTCOMES AND MEASURES

Predefined outcomes of this analysis were mean eGFR change and a 25% or greater eGFR decline from baseline. The eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation.

RESULTS

Of 4640 participants in the once-daily TDF (n = 1548), FTC-TDF (n = 1545), or placebo (n = 1547) groups, 63% were men. At enrollment, median age was 35 years (range, 18-64 years), and mean eGFR was 130 mL/min/1.73 m². During a median follow-up of 18 months (interquartile range 12-27 months), mean within-group eGFR change from baseline was +0.14 mL/min/1.73 m² for TDF, -0.22 mL/min/1.73 m² for FTC-TDF, and +1.37 mL/min/1.73 m² for placebo, translating into average declines in eGFR attributable to PrEP vs placebo of -1.23 mL/min/1.73 m² (95% CI, -2.06 to -0.40; P = .004) for TDF and -1.59 mL/min/1.73 m² (95% CI, -2.44 to -0.74; P < .001) for FTC-TDF. The difference in mean eGFR between PrEP and placebo appeared by 1 month after randomization, was stable through 12 months, and then appeared to wane thereafter. The respective proportions of persons who developed a confirmed 25% or greater eGFR decline from baseline by 12 and 24 months was 1.3% and 1.8% for TDF and 1.2% and 2.5% for FTC-TDF, and these frequencies were not statistically different from the confirmed decline in the placebo group (0.9% and 1.3% by 12 and 24 months, respectively).

CONCLUSIONS AND RELEVANCE

In this large randomized, placebo-controlled trial among heterosexual persons, with median follow-up of 18 months and maximum follow-up of 36 months, daily oral TDF-based PrEP resulted in a small but nonprogressive decline in eGFR that was not accompanied by a substantial increase in the risk of clinically relevant (≥25%) eGFR decline.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00557245.

Diminished impact of ethnicity as a risk factor for chronic kidney disease in the current HIV treatment era

BACKGROUND

Chronic kidney disease (CKD) is an important comorbidity during human immunodeficiency virus (HIV) infection. Historically, HIV-associated nephropathy has been the predominant cause of CKD and has primarily been observed in people of African ancestry. This study aims to investigate the role of ethnicity in relation to CKD risk in recent years.

METHODS

Analyses were performed including 16 836 patients from the Dutch AIDS Therapy Evaluation in the Netherlands (ATHENA) cohort. Baseline was defined as the first available creatinine level measurement after 1 January 2007; CKD was defined as a glomerular filtration rate of <60 mL/min/1.73 m(2). The associations between ethnicity and both prevalent CKD at baseline and incident CKD during follow-up were analyzed.

RESULTS

The prevalence of baseline CKD was 2.7% (460 of 16 836 patients). Birth in a sub-Saharan African country (hereafter, "SSA origin") was significantly associated with baseline CKD (adjusted odds ratio 1.49; 95% confidence interval [CI], 1.04-2.13). During follow-up (median duration, 4.7 years; interquartile range, 2.4-5.2), the rate of incident CKD was 6.0 events per 1000 person-years. The risk of newly developing CKD was similar between patients of SSA origin and those born in Western Europe, Australia, or New Zealand (adjusted hazard ratio, 1.00; 95% CI, .63-1.59).

CONCLUSIONS

Among HIV-infected patients in the Netherlands, being of SSA origin was associated with a higher baseline CKD prevalence but had no impact on newly developing CKD over time. This suggests a shift in the etiology of CKD from HIV-associated nephropathy toward other etiologies.

Protease Inhibitors and Renal Function in Patients with HIV Infection: a Systematic Review

INTRODUCTION

Despite antiretroviral (ARV) therapy reducing renal disease in human immunodeficiency virus overall, there is concern that certain ARVs, particularly tenofovir disoproxil fumarate (TDF) with or without a boosted protease inhibitor (PI), may reduce renal function over time. It is not known whether effects seen with PI-based regimens are independent, result from interactions with TDF coadministration, or are artefactual owing to inhibition of renal tubular creatinine transport by ritonavir or cobicistat pharmacoenhancement. The aim of this review was to conduct a systematic review of studies, weighted toward high-quality evidence, examining changes in renal function over time with PI-based regimens.

METHODS

PubMed, Embase, and Medline databases and conference abstracts were searched using pre-defined terms for English language articles, published up to and including August 12, 2013, describing changes in renal function over time with PI-based regimens. All available randomized controlled trials (RCTs) were selected; however, to reduce bias, only observational studies recruiting from more than one center and analyzing data from more than 1,000 patients were included. Evidence was qualitatively evaluated according to levels established by the Oxford Centre for Evidence-Based Medicine (OCEBM).

RESULTS

A total of 2,322 articles were retrieved by the initial search. Of these, 37 were selected for full review, comprising 24 RCTs (OCEBM Level 1 evidence: 4 reports of fully double-blinded or blinded with respect to the PI component). The remaining 20 RCTs and 13 observational studies qualified as OCEBM Level 2 evidence. Level 1 evidence showed initial but non-progressive increases in serum creatinine and corresponding decreases in estimated glomerular filtration rate (eGFR), suggesting an effect on renal tubular transport of creatinine. Level 2 evidence suggested that atazanavir and lopinavir especially in combination with TDF were associated with non-progressive reductions in eGFR over time, with a decreased risk for the development of chronic kidney disease (CKD) on cessation and without the development of advanced CKD or end-stage renal disease (ESRD); whether these reductions were independent or associated with interactions with coadministered TDF could not be established with certainty. Data on darunavir were insufficient to draw any conclusions. The principal limitation of the reviewed studies was the lack of standardization of creatinine measurements in virtually all studies and the lack of corroborative data on changes in proteinuria or other indices of renal function.

DISCUSSION

In this review, there was little evidence for progressive changes in eGFR, or the development of advanced CKD, or ESRD with lopinavir or atazanavir. Further long-term studies, employing a wide range of validated renal function assessments, are required to fully evaluate potential association of PIs with CKD.

Liver and renal safety of tenofovir disoproxil fumarate in combination with emtricitabine among African women in a pre-exposure prophylaxis trial

BACKGROUND

Safety of tenofovir disoproxil fumarate/emtricitabine (TDF-FTC) has been studied more extensively among HIV-infected patients than among HIV-uninfected people. Using data from a pre-exposure trial - FEM-PrEP -, we determined the cumulative probabilities of grade 1+ ALT, AST and creatinine and grade 2+ phosphorus toxicities; ALT/AST toxicities by baseline hepatitis B status; and change in mean creatinine, phosphorus, ALT and AST levels controlling for TDF-FTC adherence.

METHODS AND FINDINGS

FEM-PrEP was a randomized, blinded, placebo-controlled trial of daily TDF-FTC among women in Africa. Enrolled women were in general good health, HIV antibody negative, 18 to 35 years old, hepatitis B surface antigen negative, and had normal hepatic and renal function at baseline. AST, ALT, phosphorus and serum creatinine were measured regularly throughout the trial. TDF-FTC concentrations were measured to assess adherence to TDF-FTC. The cumulative probabilities of grade 1+ creatininemia and grade 2+ phosphatemia toxicities were not statistically different between TDF-FTC and placebo arms. The cumulative probabilities of grade 1+ ALT and AST toxicities were higher among participants in the TDF-FTC arm than in the placebo arm (p = 0.03 for both). The proportions of grade 1+ and grade 2+ ALT or AST toxicities were significantly higher in participants who were hepatitis B virus surface antibody (HBsAb) positive than in those who were HBsAb-negative. Women with good adherence had higher mean change from baseline to week 4 in their AST levels (2.90 (0.37, 5.42); p = 0.025) than women with less than good adherence.

CONCLUSIONS

We did not observe a significant relationship between randomization to TDF-FTC and creatinine or phosphorus toxicities. Women randomized to TDF-FTC had higher rates of mild to moderate ALT/AST toxicities, especially women with prior hepatitis B virus exposure. We also observed a significant increase in AST from baseline to week 4 among women who had higher adherence to TDF-FTC during that interval.

TRIAL REGISTER

#NCT00625404, February 19, 2008.

Clinical practice guideline for the management of chronic kidney disease in patients infected with HIV: 2014 update by the HIV Medicine Association of the Infectious Diseases Society of America

It is important to realize that guidelines cannot always account for individual variation among patients. They are not intended to supplant physician judgment with respect to particular patients or special clinical situations. IDSA considers adherence to these guidelines to be voluntary, with the ultimate determination regarding their application to be made by the physician in the light of each patient's individual circumstances.

High prevalence of signs of renal damage despite normal renal function in a cohort of HIV-infected patients: evaluation of associated factors

Renal disorders are an emerging problem in HIV-infected patients. We performed a cross-sectional study of the first 1000 HIV-infected patients attended at our HIV unit who agreed to participate. We determined the frequency of renal alterations and its related risk factors. Summary statistics and logistic regression were applied. The study sample comprised 970 patients with complete data. Most were white (94%) and men (76%). Median (IQR) age was 48 (42-53) years. Hypertension was diagnosed in 19%, dyslipidemia in 27%, and diabetes mellitus in 3%. According to the Chronic Kidney Disease Epidemiology Collaboration (CKD EPI) equation, 29 patients (3%) had an eGFR<60 ml/min/1.73 m(2); 18 of them (62%) presented altered albumin/creatinine and protein/creatinine (UPC or UAC) ratios. Of the patients with eGFR>60 mL/min, it was present in 293 (30%), 38 of whom (7.1%) had UPC>300 mg/g. Increased risk of renal abnormalities was correlated with hypertension (OR, 1.821 [95%CI, 1.292;2.564]; p=0.001), age (OR, 1.015 [95%CI, 1.001;1.030], per one year; p=0.040), and use of tenofovir disoproxil fumarate (TDF) plus protease inhibitor (PI), (OR, 1.401 [95%CI, 1.078;1.821]; p=0.012). Current CD4 cell count was a protective factor (OR, 0.9995 [95%CI, 0.9991;0.9999], per one cell; p=0.035). A considerable proportion of patients presented altered UPC or UAC ratios, despite having an eGFR>60 mL/min. CD4 cell count was a protective factor; age, hypertension, and use of TDF plus PIs were risk factors for renal abnormalities. Based on our results, screen of renal abnormalities should be considered in all HIV-infected patients to detect these alterations early.