Comparison of Tolerability and Impact on Metabolic Profiles of Antiretroviral Regimens Containing Darunavir/Ritonavir or Darunavir/Cobicistat in Romanian HIV Infected Patients

The management of the side effects caused by the antiretroviral therapy is one of the main problems facing clinicians. The patient's tolerability and safety influence the success of the therapy. This retrospective study assesses the tolerability and impact on metabolic profiles of antiretroviral regimens containing darunavir/ritonavir (DRV/r) versus those containing darunavir/cobicistat (DRV/c), in routine clinical practice. The database of Prof. Dr Matei Bals of the National Institute of Infectious Diseases (INBI MB) was studied for the period 2017-2020, allowing the inclusion in the study of 462 HIV-infected patients who received the current regimen at least three months before evaluation. The following parameters were collected and analyzed: significant medical history, associated diseases, serum levels for profile evaluation: carbohydrate, lipidic, serum level of liver and pancreatic enzymes, serum markers of cardiac function, coagulation, and renal function. DRV/c (800 mg/150 mg, once daily) administrated in combination with other antiretroviral (ARV) in HIV-1 infected subjects proved to be better tolerated and with a lower impact on metabolic profile than DRV/r (600 mg/100 mg, twice daily). Patients in DRV/r group are significantly more at risk of developing, over time, side effects and metabolic impairments than those in DRV/c group, in all body functions studied, with statistically significant differences (p < 0.05) between the two groups. Laboratory data were correlated with patient's demographic and clinical characteristics and statistically significant outcomes have been found, proving that a personalized regimen is needed to minimize the ART side effects and to maximize the success of therapy. The results of the study showed that DRV/c, associated with other antiretroviral drugs in the regimens of Romanian HIV infected subjects, have a more favorable metabolic profile than those containing DRV/r.

Incidence and Risk Factors for Renal Disease in an Outpatient Cohort of HIV-Infected Patients on Antiretroviral Therapy

Introduction

Prior studies found renal disease was common among HIV-infected outpatients. We updated incident renal disease estimates in this population, comparing those with and without tenofovir exposure.

Methods

We conducted a retrospective analysis of the DC Cohort, a longitudinal study of HIV patients in Washington, DC, from 2011 to 2015. We included adults prescribed antiretroviral therapy (ART) with baseline glomerular filtration rate (GFR) ≥15 ml/min per 1.73 m². We defined renal disease as 50% decrease in GFR or doubled serum creatinine (Cr) within 3 months. We defined cumulative viral load as area under the curve (AUC) of log₁₀ transformed longitudinal HIV RNA viral load (VL). Correlates of time to incident renal disease were identified using Cox proportional hazard regression models, adjusted for demographics and known risk factors for kidney disease.

Results

Among 6068 adults, 77% were Black and median age was 48 years. Incident renal disease rate was 0.77 per 100 person-years (95% confidence interval [CI]: 0.65-0.9). Factors associated with renal disease were age (adjusted hazard ratio [aHR]: 1.4; CI 1.1-1.7 per 10 years), public non-Medicaid, non-Medicare insurance (aHR: 3.4; CI: 1.9-6.4), AUC VL (aHR: 1.1; CI: 1.1-1.2), diabetes mellitus (aHR: 1.6; CI: 1.0-2.4), and mildly reduced GFR (60-89 ml/min per 1.73 m²) (aHR: 1.5; CI: 1.0-2.3); recent tenofovir exposure was not associated with renal disease (aHR: 0.7; CI: 0.5-1.1).

Conclusion

Our study revealed a substantial burden of renal disease among HIV patients. Cumulative VL was associated with renal disease, suggesting that early VL suppression may decrease its incidence.

Predictors of HIV-associated nephropathy

Renal disease accounts for significant morbidity and mortality in patients with HIV-1 infection. HIV-associated nephropathy (HIVAN) is an important cause of end stage renal disease in this population. Although multiple genetic, clinical, and laboratory characteristics such as Apolipoproetin-1 genetic polymorphism, high viral load, low CD-4 count, nephrotic range proteinuria, and increased renal echogenicity on ultrasound are predictive of HIVAN, kidney biopsy remains the gold standard to make the definitive diagnosis. Current treatment options for HIVAN include initiation of combined active antiretroviral therapy, blockade of the renin-angiotensin system, and steroids. In patients with progression of HIVAN, renal transplant should be pursued as long as their systemic HIV infection is controlled.

Fanconi syndrome accompanied by renal function decline with tenofovir disoproxil fumarate: a prospective, case-control study of predictors and resolution in HIV-infected patients

Objective

The predictors of Fanconi syndrome (FS) accompanied by renal function decline with use of the antiretroviral tenofovir disoproxil fumarate (TDF) have not been assessed. In addition, the natural history of renal recovery from FS after TDF discontinuation is not well-described.

Design

We prospectively enrolled HIV-infected patients receiving TDF with newly identified FS (defined as at least two markers of proximal tubulopathy and either a >25% decline in creatinine clearance (CrCl) from pre-TDF values or a CrCl <60 mL/min in those without a known pre-TDF CrCl) in a multicenter observational study. These case participants were matched 1∶2 to controls; characteristics between the two groups were compared. Case participants with known pre-TDF CrCl values were then followed over 48 weeks to assess renal recovery.

Results

Nineteen cases and 37 controls were enrolled. In multivariable analysis, previous or concurrent use of lopinavir/ritonavir [OR 16.37, 95% CI (2.28, 117.68); P = 0.006] and reduced creatinine clearance prior to initiation of TDF [OR 1.44 for every 5 mL/min reduction, 95% CI (1.09, 1.92); P = 0.012; OR 19.77 for pre-TDF CrCl lower than 83 mL/min, 95% CI (2.24, 174.67); P = 0.007] were significantly associated with FS. Of the 14 cases followed for resolution, 7 (50%) achieved at least partial resolution (defined as recovering CrCl >70% of pre-TDF values) although most participants had full normalization of proximal tubulopathy markers within two months of TDF discontinuation.

Conclusions

FS, defined by specific CrCl decreases and markers of tubulopathy, is more likely in those who have received or are currently receiving concomitant lopinavir/ritonavir or who had lower CrCl prior to TDF initiation. Half of those with protocol-defined FS had CrCl recover to near pre-TDF values during the first year after TDF discontinuation.

Microalbuminuria in HIV disease

BACKGROUND/AIMS

Microalbuminuria is a marker for early kidney disease and cardiovascular risk. The purposes of this study were to determine the prevalence of microalbuminuria in an HIV-infected clinic population, to test the predictive value of a single urine albumin/creatinine ratio (ACR) to identify persistent microalbuminuria and to examine covariates of microalbuminuria.

METHODS

We conducted a prospective cohort study of HIV-infected subjects (n = 182) without proteinuria (urine protein/creatinine ratio ≥0.5 g/g), elevated serum creatinine, diabetes, or chronic inflammatory conditions. Subjects completed three research visits within 9 months. Microalbuminuria was defined as the geometric mean ACR of 25-355 mg/g for females and 17-250 mg/g for males.

RESULTS

The prevalence of microalbuminuria was 14%. The negative predictive value of a single urine ACR determination was 98%, whereas the positive predictive value was only 74%. Microalbuminuria was similar among Black (15%) and non-Black (14%) subjects (p = 0.8). Subjects with microalbuminuria were more likely to have hypertension (p = 0.02) and metabolic syndrome (p = 0.03). While duration of HIV infection and the level of HIV viremia were similar between groups, those with microalbuminuria were more likely to have a CD4 count <200 cells/μl (p = 0.0003). In a multivariate logistic regression analysis, the only significant independent predictors of microalbuminuria were low CD4 count (p = 0.018) and current ritonavir exposure (p = 0.04).

CONCLUSION

The prevalence of microalbuminuria in an HIV-infected clinic population was similar to earlier reports, and was associated with hypertension and impaired immune function. A single normal ACR determination effectively excludes microalbuminuria, whereas an elevated ACR requires confirmation.

HIV compromises integrity of the podocyte actin cytoskeleton through downregulation of the vitamin D receptor

Alterations in the podocyte actin cytoskeleton have been implicated in the development of proteinuric kidney diseases. In the present study, we evaluated the effect of HIV on the podocyte actin cytoskeleton and the mechanism involved. We hypothesized that HIV may be compromising the actin cytoskeleton via downregulation of the vitamin D receptor (VDR) of conditionally immortalized differentiated human podocytes (CIDHPs). HIV-transduced podocytes (HIV/CIDHPs) not only displayed downregulation of VDR but also showed activation of the renin-angiotensin system (RAS) in the form of enhanced expression of renin and increased production of ANG II. Moreover, CIDHPs lacking VDR displayed enhanced ANG II production, and treatment of HIV/CIDHPs with EB1089 (vitamin D3; VD) attenuated ANG II production. HIV/CIDHPs as well as ANG II-treated CIDHPs exhibited enhanced expression of cathepsin (CTS) L. Additionally, losartan (an ANG II type I receptor blocker) inhibited both HIV- and ANG II-induced podocyte cathepsin L expression. Furthermore, VD downregulated HIV-induced podocyte CTSL expression. Both losartan and free radical scavengers attenuated HIV- and ANG II-induced podocyte reactive oxygen species (ROS) generation. HIV also led to cytosolic CTSL accumulation through enhancement of podocyte lysosomal membrane permeabilization; on the other hand, VD, losartan, and superoxide dismutase (SOD) attenuated HIV-induced enhanced podocyte cytosolic CTSL accumulation. Morphological evaluation of HIV/CIDHPs revealed sparse actin filaments and attenuated expression of dynamin. Interestingly, podocytes lacking CTSL displayed enhanced dynamin expression, and HIV/CIDHPs expressing CTSL exhibited downregulation of dynamin. These findings indicate that HIV-induced downregulation of podocyte VDR and associated RAS activation and cytosolic CTSL accumulation compromised the actin cytoskeleton.

Interventions for HIV-associated nephropathy

BACKGROUND

Human immunodeficiency virus-associated nephropathy (HIVAN) is the most common cause of end stage kidney disease (ESKD) in human immunodeficiency virus-1 (HIV-1) serotype patients and it mostly affects patients of African descent. It rapidly progresses to ESKD if untreated. The goal of treatment is directed toward reducing HIV-1 replication and/or slowing the progression of chronic kidney disease. The following pharmacological agents have been used for the treatment of HIVAN: antiretroviral therapy, angiotensin-converting enzyme inhibitors (ACEi), steroids and recently cyclosporin. Despite this, the effect of each intervention is yet to be evaluated.

OBJECTIVES

To evaluate the benefits and harms of adjunctive therapies in the management of HIVAN and its effects on symptom severity and all-cause mortality.

SEARCH METHODS

In January 2012 we searched the Cochrane Renal Group's Specialised Register, AIDS Education Global Information System (AEGIS database), ClinicalTrial.gov, the WHO International Clinical Trials Registry Portal, and reference lists of retrieved articles without language restrictions. In our original review we searched CENTRAL, MEDLINE, EMBASE, and AIDSearch, in addition to contacting individual researchers, research organisations and pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of any therapy used in the treatment of HIVAN.

DATA COLLECTION AND ANALYSIS

We independently screened the search outputs for relevant studies and to retrieve full articles when necessary. For dichotomous outcomes results were to be expressed as risk ratios with 95% confidence intervals, and for continuous scales of measurement the mean difference was to be used.

MAIN RESULTS

We identified four relevant ongoing studies: one is still ongoing; two have completed recruitment but are yet to be published; and the fourth study was suspended for unspecified reasons. No completed RCTs or quasi-RCTs were identified. We summarised and tabulated the data from the observational studies, however no formal analyses were performed.

AUTHORS' CONCLUSIONS

There is currently no RCT-based evidence upon which to base guidelines for the treatment of HIVAN, however three ongoing studies have been identified. Data from observational studies suggest steroids and angiotensin-converting enzyme inhibitors appear to improve kidney function in patients with HIVAN, however no formal analyses were performed in this review. This review highlights the need for good quality RCTs to address the effects of interventions for treating this group.

Baseline kidney function as predictor of mortality and kidney disease progression in HIV-positive patients

BACKGROUND

Chronic kidney disease (CKD) is associated with increased all-cause mortality and kidney disease progression. Decreased kidney function at baseline may identify human immunodeficiency virus (HIV)-positive patients at increased risk of death and kidney disease progression.

STUDY DESIGN

Observational cohort study.

SETTING & PARTICIPANTS

7 large HIV cohorts in the United Kingdom with kidney function data available for 20,132 patients.

PREDICTOR

Baseline estimated glomerular filtration rate (eGFR).

OUTCOMES

Death and progression to stages 4-5 CKD (eGFR <30 mL/min/1.73 m(2) for >3 months) in Cox proportional hazards and competing-risk regression models.

RESULTS

Median age at baseline was 34 (25th-75th percentile, 30-40) years, median CD4 cell count was 350 (25th-75th percentile, 208-520) cells/μL, and median eGFR was 100 (25th-75th percentile, 87-112) mL/min/1.73 m(2). Patients were followed up for a median of 5.3 (25th-75th percentile, 2.0-8.9) years, during which 1,820 died and 56 progressed to stages 4-5 CKD. A U-shaped relationship between baseline eGFR and mortality was observed. After adjustment for potential confounders, eGFRs <45 and >105 mL/min/1.73 m(2) remained associated significantly with increased risk of death. Baseline eGFR <90 mL/min/1.73 m(2) was associated with increased risk of kidney disease progression, with the highest incidence rates of stages 4-5 CKD (>3 events/100 person-years) observed in black patients with eGFR of 30-59 mL/min/1.73 m(2) and those of white/other ethnicity with eGFR of 30-44 mL/min/1.73 m(2).

LIMITATIONS

The relatively small numbers of patients with decreased eGFR at baseline and low rates of progression to stages 4-5 CKD and lack of data for diabetes, hypertension, and proteinuria.

CONCLUSIONS

Although stages 4-5 CKD were uncommon in this cohort, baseline eGFR allowed the identification of patients at increased risk of death and at greatest risk of kidney disease progression.

Rapamycin-induced modulation of HIV gene transcription attenuates progression of HIVAN

HIV-associated nephropathy (HIVAN) is the manifestation of HIV gene expression by kidney cells in the presence of specific host factors. Recently, rapamycin (sirolimus) has been demonstrated to modulate the progression of HIVAN. We hypothesized that rapamycin would modulate the progression of HIVAN by attenuating HIV gene expression. To test our hypothesis, three weeks old Tg26 mice (n=6) were administered either vehicle or rapamycin (5 mg/kg, every other day, intraperitoneal) for eight weeks. At the end of the experimental period, the kidneys were harvested. In in vitro studies, human podocytes were transduced with either HIV-1 (NL4-3) or empty vector (EV), followed by treatment with either vehicle or rapamycin. Total RNA and proteins were extracted from renal tissues/cellular lysates and HIV gene transcription/translation was measured by real time PCR and Western blotting studies. Renal histological slides were graded for glomerular sclerosis and tubular dilatation with microcyst formation. Rapamycin attenuated both glomerular and tubular lesions in Tg26 mice. Rapamycin decreased transcription of HIV genes both in renal tissues as well as in HIV-1 transduced podocytes. Our data strongly indicate that HIV-1 long terminal repeat-mediated transcriptional activity was targeted by rapamycin. Rapamycin enhanced podocyte NF-κB and CREB activities but then it decreased AP-1 binding activity. Since expression of HIV genes by kidney cells has been demonstrated to be the key factor in the development HIVAN, it appears that rapamycin-induced altered transcription of HIV genes might have partly contributed to its disease modulating effects.

Renal toxicity associated with antiretroviral therapy

Renal disease is becoming an increasingly prevalent comorbidity in patients with human immunodeficiency virus (HIV) infection. The increase in life expectancy following the introduction of highly active antiretroviral therapy (HAART) and the long-term development of metabolic complications (such as diabetes and dyslipidaemia), hypertension, and vascular diseases can contribute to the increasing frequency in the recognition of renal impairment in HIV-infected patients. Some antiretroviral agents, and particularly tenofovir, have been associated with nephrotoxic drug effects, including decline in glomerular filtration rate, proximal tubular damage, and acute kidney injury. The occurrence of clinically evident renal toxicity in patients treated with HAART seems to be very low, but glomerular or tubular subclinical dysfunction may occur more frequently. Therefore, careful clinical and laboratory monitoring for the early recognition of renal abnormalities is recommended for all subjects receiving antiretroviral treatment. In this article, the current knowledge about the nephrotoxic effects of antiretroviral agents has been reviewed, and an algorithm for screening and management of HAART-related kidney disease is proposed in the light of the most recent clinical studies and international guidelines.

Nef interaction with actin compromises human podocyte actin cytoskeletal integrity

The HIV-1 accessory protein Nef is considered to play an important role in the development of a podocyte phenotype in HIV-1 associated nephropathy. We hypothesized that Nef may be altering the podocyte phenotype both structurally and functionally. To elucidate the involved mechanisms, podocyte proteins interacting with Nef were identified using GST pull down assay and yeast two hybrid assay. The GST pull down assay on protein extracts made from stable colonies of conditionally immortalized human podocytes expressing Nef (Nef/CIHP) displayed a band at 45 kD, which was identified as actin by mass spectrometry. Yeast two hybrid assay identified the following Nef-interacting proteins: syntrophin, filamin B, syntaxin, translational elongation factor 1, and zyxin. The Nef-actin and Nef-zyxin interactions were confirmed by co-localization studies on Nef/CIHP stable cell lines. The co-localization studies also showed that Nef/CIHP stable cell lines had a decreased number of actin filaments (stress fibers), displayed formation of lamellipodia, and increased number of podocyte projections (filopodia). Nef/CIHP displayed an enhanced cortical F-actin score index (P<0.001) and thus indicated a reorganization of F-actin in the cortical regions. Microarray analysis showed that Nef enhanced the expression of Rac1, syndecan-4, Rif, and CDC42 and attenuated the expression of syndecan-3 and syntenin. In addition, Nef/CIHPs displayed a diminished sphingomyelinase (ASMase) activity. Functionally, Nef/CIHPs displayed diminished attachment and enhanced detachment to their substrate. These findings indicate that Nef interaction with actin compromises the podocyte cytoskeleton integrity.

Susceptibility genes in common complex kidney disease

PURPOSE OF REVIEW

This paper reviews recent efforts to identify genetic variants conferring risk for chronic kidney disease. A brief overview of methods for identifying gene variants is provided, along with genetic associations and new avenues under exploration.

RECENT FINDINGS

The role of renal failure susceptibility genes, including MYH9, ELMO1, UMOD and ACTN4, has become clearer over the past 18 months. The spectrum of MYH9-associated kidney disease, including focal segmental glomerulosclerosis, global glomerulosclerosis and collapsing glomerulopathy, related entities contributing to approximately 43% of end-stage renal disease in African-Americans, has come to light.

SUMMARY

MYH9 will re-categorize focal segmental glomerulosclerosis and related disorders, and has clarified the relationship between hypertension and kidney disease. MYH9 polymorphisms account for much of the excess risk of HIV-associated nephropathy and nondiabetic kidney disease in African-Americans. Kidney disease associations with ELMO1 and UMOD have been replicated and applications of genome-wide association studies based on expression data are providing novel insights on renal protein expression. These breakthroughs will alter our approach to kidney disease surveillance and lead to new therapeutic options.

Regulation of HIV-1 transcription in cells of the monocyte-macrophage lineage

Human immunodeficiency virus type 1 (HIV-1) has been shown to replicate productively in cells of the monocyte-macrophage lineage, although replication occurs to a lesser extent than in infected T cells. As cells of the monocyte-macrophage lineage become differentiated and activated and subsequently travel to a variety of end organs, they become a source of infectious virus and secreted viral proteins and cellular products that likely initiate pathological consequences in a number of organ systems. During this process, alterations in a number of signaling pathways, including the level and functional properties of many cellular transcription factors, alter the course of HIV-1 long terminal repeat (LTR)-directed gene expression. This process ultimately results in events that contribute to the pathogenesis of HIV-1 infection. First, increased transcription leads to the upregulation of infectious virus production, and the increased production of viral proteins (gp120, Tat, Nef, and Vpr), which have additional activities as extracellular proteins. Increased viral production and the presence of toxic proteins lead to enhanced deregulation of cellular functions increasing the production of toxic cellular proteins and metabolites and the resulting organ-specific pathologic consequences such as neuroAIDS. This article reviews the structural and functional features of the cis-acting elements upstream and downstream of the transcriptional start site in the retroviral LTR. It also includes a discussion of the regulation of the retroviral LTR in the monocyte-macrophage lineage during virus infection of the bone marrow, the peripheral blood, the lymphoid tissues, and end organs such as the brain. The impact of genetic variation on LTR-directed transcription during the course of retrovirus disease is also reviewed.

Interventions for HIV-associated nephropathy

BACKGROUND

Human immunodeficiency virus associated nephropathy (HIVAN) is the most common cause of end stage kidney disease (ESKD) in Human immunodeficiency virus-1 (HIV-1) serotype patients and it mostly affects patients of African descent. It rapidly progresses to ESKD if untreated. The goal of treatment is directed toward reducing HIV-1 replication and/or slowing the progression of chronic kidney disease. The following pharmacological agents have been used for the treatment of HIVAN: antiretrovirals, angiotensin-converting enzyme inhibitors (ACEi), steroids and recently cyclosporin. Despite this, the effect of each intervention is yet to be evaluated.

OBJECTIVES

To evaluate the benefits and harms of adjunctive therapies in the management of HIVAN and its effects on symptom severity and all-cause mortality.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Renal Group's specialised register, MEDLINE, EMBASE, AIDSearch, reference lists of articles and conference proceedings without language restrictions. We searched the international clinical trials registry platform search portal and also contacted individual researchers, research organisations and pharmaceutical companies that manufacture the drugs used for interventions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of any therapy used in the treatment of HIVAN.

DATA COLLECTION AND ANALYSIS

We independently screened the search outputs for relevant studies and to retrieve full articles when necessary. We applied the inclusion criteria to identify four relevant ongoing studies, one is ongoing while the remaining two have completed recruitment and are yet to be published. The fourth study was suspended for an unknown reason.

MAIN RESULTS

No completed RCTs or quasi-RCTs were identified to be included in the study.

AUTHORS' CONCLUSIONS

There is no RCT-based evidence upon which to base guidelines for the treatment of HIVAN. However, steroids and ACEI appear to improve the kidney function of patients in the observational studies that were identified. This review highlights the need for good quality RCTs to address the effects of interventions for treating this group.

Urinary NGAL marks cystic disease in HIV-associated nephropathy

Nephrosis and a rapid decline in kidney function characterize HIV-associated nephropathy (HIVAN). Histologically, HIVAN is a collapsing focal segmental glomerulosclerosis with prominent tubular damage. We explored the expression of neutrophil gelatinase-associated lipocalin (NGAL), a marker of tubular injury, to determine whether this protein has the potential to aid in the noninvasive diagnosis of HIVAN. We found that expression of urinary NGAL was much higher in patients with biopsy-proven HIVAN than in HIV-positive and HIV-negative patients with other forms of chronic kidney disease. In the HIV-transgenic mouse model of HIVAN, NGAL mRNA was abundant in dilated, microcystic segments of the nephron. In contrast, urinary NGAL did not correlate with proteinuria in human or in mouse models. These data show that marked upregulation of NGAL accompanies HIVAN and support further study of uNGAL levels in large cohorts to aid in the noninvasive diagnosis of HIVAN and screen for HIVAN-related tubular damage.

Kidney tubular abnormalities in the absence of impaired glomerular function in HIV patients treated with tenofovir

BACKGROUND

Tenofovir (TDF) is the most widely prescribed antiretroviral drug. Kidney abnormalities are the main concern using the drug. As glomerular function is infrequently affected in patients treated with TDF, herein, we report the results of an extensive examination of tubular function.

METHODS

Cross-sectional study of plasma and 24 h urine markers of kidney tubulopathy (glucosuria, hyperaminoaciduria, hyperphosphaturia, hyperuricosuria and beta2-microglobulinuria) could be allocated in three groups: patients under a TDF-containing HAART; patients on HAART never exposed to TDF; and antiretroviral-naive individuals. Significant tubular damage was defined when at least two of these parameters were repeatedly present, being at least one part of the Fanconi syndrome criteria (glucosuria, hyperaminoaciduria and hyperphosphaturia). Glomerular function was assessed using creatinine clearance.

RESULTS

A total of 284 consecutive HIV patients were examined, 154 on TDF, 49 on other HAART regimens and 81 drug-naive. No significant differences in creatinine clearance were observed when comparing distinct groups. The proportion of patients with tubular damage in groups 1, 2 and 3 were 22, 6 and 12%, respectively. In a multivariate analysis [odds ratio (OR) {95% confidence interval (CI)} P], the only independent predictors of tubular dysfunction were TDF use (21.6, 4.1-113, <0.001) and older age (1.1 per year, 1.0-1.1, 0.01).

CONCLUSION

Exposure to TDF is associated with an increased risk over time of kidney tubular abnormalities in the absence of significant impaired glomerular function. Although long-term consequences of this tubulopathy are unknown, close monitoring of accelerated bone mineral loss and renal insufficiency are warranted. Periodic screening of tubular function parameters should be recommended to patients receiving TDF.