Antiretroviral therapy in the treatment of HIV-associated nephropathy

Renal outcomes in adults with HBV, HIV and HBV/HIV coinfection after 3 years of antiviral therapy in urban Tanzania

BACKGROUND

An enhanced understanding of renal outcomes in persons with chronic HBV, HIV, and HBV/HIV coinfection is needed to mitigate chronic kidney disease in regions where HBV and HIV are endemic.

OBJECTIVES

To investigate changes in estimated glomerular filtration rate (eGFR) in adults with HBV, HIV or HBV/HIV enrolled in a 3 year prospective cohort study of liver outcomes in Dar es Salaam, Tanzania and initiated on antiviral therapy.

METHODS

We compared eGFR between and within groups over time using mixed-effects models.

RESULTS

Four hundred and ninety-nine participants were included in the analysis (HBV: 164; HIV: 271; HBV/HIV: 64). Mean baseline eGFRs were 106.88, 106.03 and 107.18 mL/min/1.73 m2, respectively. From baseline to Year 3, mean eGFR declined by 4.3 mL/min/1.73 m2 (95% CI -9.3 to 0.7) and 3.7 (-7.8 to 0.5) in participants with HBV and HIV, respectively, and increased by 5.1 (-4.7 to 14.9) in those with HBV/HIV. In multivariable models, participants with HBV had lower eGFRs compared with those with HIV or HBV/HIV and, after adjusting for HBV DNA level and hepatitis B e antigen (HBeAg) status, significantly lower eGFRs than those with HBV/HIV at all follow-up visits.

CONCLUSIONS

In this Tanzanian cohort, coinfection with HBV/HIV did not appear to exacerbate renal dysfunction compared with those with either infection alone. Although overall changes in eGFR were small, persons with HBV experienced lower eGFRs throughout follow-up despite their younger age and similar baseline values. Longer-term studies are needed to evaluate continuing changes in eGFR and contributions from infection duration and other comorbidities.

Updates on HIV and Kidney Disease

PURPOSE OF REVIEW

With the advent of antiretroviral therapy, HIV infection has become a chronic disease in developed countries.

RECENT FINDINGS

Non-HIV-driven risk factors for kidney disease, such as APOL1 risk variants and other genetic and environmental factors, have been discovered and are better described. Consequently, the field of HIV-associated kidney disease has evolved with greater attention given to traditional risk factors of CKD and antiretroviral treatment's nephrotoxicity. In this review, we explore risk factors of HIV-associated kidney disease, diagnostic tools, kidney pathology in HIV-positive individuals, and antiretroviral therapy-associated nephrotoxicity.

Collapsing Glomerulopathy: A Review by the Collapsing Brazilian Consortium

Collapsing glomerulopathy (CG) is a clinicopathologic entity characterized by segmentar or global collapse of the glomerulus and hypertrophy and hyperplasia of podocytes. The Columbia classification of 2004 classified CG as a histological subtype of focal segmental glomerulosclerosis (FSGS). A growing number of studies have demonstrated a high prevalence of CG in many countries, especially among populations with a higher proportion of people with African descent. The present study is a narrative review of articles extracted from PubMed, Medline, and Scielo databases from September 1, 2020 to December 31, 2021. We have focused on populational studies (specially cross-sectional and cohort articles). CG is defined as a podocytopathy with a distinct pathogenesis characterized by strong podocyte proliferative activity. The most significant risk factors for CG include APOL1 gene mutations and infections with human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2. CG typically presents with more severe symptoms and greater renal damage. The prognosis is notably worse than that of other FSGS subtypes.

Impact of Antiretroviral Therapy on Kidney Disease in HIV Infected Individuals - A Qualitative Systematic Review

Kidney disease is the fourth most common cause of non-AIDS-related mortality in people living with HIV. Combination antiretroviral therapy (cART) remains the cornerstone of treatment. However, little is known about the impact of cART on disease outcomes in patients with HIV-associated nephropathy (HIVAN) and HIV-immune complex kidney disease (HIVICK). This systematic review evaluates the impact of cART on progression to end-stage kidney disease (ESKD) and other outcomes in HIV-infected individuals. We conducted a literature search utilizing PubMed, and Cochrane database and 11 articles met inclusion criteria for analysis of which nine HIVAN studies showed decreased progression to ESKD or death for subjects when treated with cART versus those untreated. However, two studies showed no survival advantage with cART. Three HIVICK studies showed improvement in delaying ESKD in subjects on cART compared to untreated subjects. cART appeared to reduce the risk to ESKD or death in patients with both HIVAN and HIVICK.

Longitudinal Outcomes of COVID-19-Associated Collapsing Glomerulopathy and Other Podocytopathies

BACKGROUND

The long-term outcome of COVID-19-associated collapsing glomerulopathy is unknown.

METHODS

We retrospectively identified 76 native kidney biopsies from patients with history of COVID-19 between March 2020 and April 2021. Presenting and outcome data were obtained for all 23 patients with collapsing glomerulopathy and for seven patients with noncollapsing podocytopathies. We performed APOL1 genotyping by Sanger sequencing, immunostaining for spike and nucleocapsid proteins, and in situ hybridization for SARS-CoV-2.

RESULTS

The 23 patients with COVID-19-associated collapsing glomerulopathy were median age 57 years (range, 35-72), included 16 men, and were predominantly (91%) Black. Severity of COVID-19 was mild or moderate in most (77%) patients. All but one patient presented with AKI, 17 had nephrotic-range proteinuria, and six had nephrotic syndrome. Fourteen (61%) patients required dialysis at presentation. Among 17 patients genotyped, 16 (94%) were high-risk APOL1. Among 22 (96%) patients with median follow-up at 155 days (range, 30-412), 11 (50%) received treatment for COVID-19, and eight (36%) received glucocorticoid therapy for podocytopathy. At follow-up, 19 (86%) patients were alive, and 15 (68%) were dialysis free, including seven of 14 who initially required dialysis. The dialysis-free patients included 64% (seven of 11) of those treated for COVID-19 and 75% (six of eight) of those treated with glucocorticoids for podocytopathy. Overall, 36% achieved partial remission of proteinuria, 32% had no remission, and 32% reached combined end points of ESKD or death. Viral infection of the kidney was not detected.

CONCLUSIONS

Half of 14 patients with COVID-19-associated collapsing glomerulopathy requiring dialysis achieved dialysis independence, but the long-term prognosis of residual proteinuric CKD remains guarded, indicating a need for more effective therapy.

Apolipoprotein-1 risk variants and associated kidney phenotypes in an adult HIV cohort in Nigeria

HIV-positive adults are at risk for various kidney diseases, and apolipoprotein 1 (APOL1) high-risk genotypes increase this risk. This study aimed to determine the prevalence and ethnic distribution of APOL1 risk genotypes among a cohort of HIV-positive Nigerian adults and explore the relationship between APOL1 risk variant status with albuminuria and estimated glomerular filtration rate (eGFR). We conducted a cross-sectional study among 2 458 persons living with HIV who attended an HIV clinic in northern Nigeria and had received antiretroviral therapy for a minimum of six months. We collected two urine samples four-eight weeks apart to measure albumin excretion, and blood samples to measure eGFR and determine APOL1 genotype. The frequency of APOL1 high-risk genotype was 6.2%, which varied by ethnic group: Hausa/Fulani (2.1%), Igbo (49.1%), and Yoruba (14.5%). The prevalence of microalbuminuria (urine/albumin creatinine ratio 30- 300 mg/g) was 37%, and prevalence of macroalbuminuria (urine/albumin creatinine ratio over 300 mg/g) was 3%. The odds of microalbuminuria and macroalbuminuria were higher for participants with the APOL1 high-risk genotype compared to those carrying the low-risk genotype ([adjusted odds ratio 1.97, 95% confidence interval 1.37-2.82] and [3.96, 1.95-8.02] respectively). APOL1 high-risk genotype participants were at higher risk of having both an eGFR under 60 ml/min/1.73m2 and urine/albumin creatinine ratio over 300 mg/g (5.56, 1.57-19.69). Thus, we found a high proportion of HIV-positive, antiretroviral therapy-experienced, and largely virologically suppressed adults had microalbuminuria. Hence, although the high-risk APOL1 genotype was less prevalent than expected, it was strongly associated with some level of albuminuria.

Renal function in a cohort of HIV-infected patients initiating antiretroviral therapy in an outpatient setting in Ethiopia

Aim

To evaluate the prevalence and associated factors of abnormal renal function among Ethiopian HIV-infected patients at baseline prior to initiation of antiretroviral therapy (ART) and during follow-up.

Methods

We conducted a retrospective observational cohort study of HIV infected patients who initiated ART at the outpatient ART clinic of Mehal Meda Hospital of North Shewa, Ethiopia from January 2012 to August 2018. Demographic and clinical data were abstracted from the medical records of patients. Renal function was assessed by estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease (MDRD) equation. Univariate and multivariate analysis were conducted to determine the factors associated with abnormal renal function at baseline and during follow-up.

Results

Among 353 patients, 70 (19.8%) had baseline eGFR <60 ml/min/1.73m² and 102 (28.9%) had eGFR = 60–89.9 ml/min/1.73m². Factors associated with baseline renal impairment (eGFR <60 ml/min/1.73m²) included female sex (AOR = 3.52, CI 1.75–7.09), CD4 count < 200 cells/mm³ (AOR = 2.75, CI 1.40–5.42), BMI < 25 Kg/m² (AOR = 3.04, CI 1.15–8.92), low hemoglobin (AOR = 2.19, CI 1.16–4.09) and high total cholesterol (AOR = 3.15, CI 1.68–5.92). After a median of 3.0 years of ART, the mean eGFR declined from 112.9 ± 81.2 ml/min/1.73m² at baseline to 93.9 ± 60.6 ml/min/1.73m² (P < 0.001). The prevalence of renal impairment increased from 19.8% at baseline to 22.1% during follow-up. Of 181 patients with baseline normal renal function, 49.7% experienced some degree of renal impairment. Older age (AOR = 3.85, 95% CI 2.03–7.31), female sex (AOR = 4.18, 95% CI 2.08–8.40), low baseline CD4 (AOR = 2.41, 95% CI 1.24–4.69), low current CD4 count (AOR = 2.32, 95% CI 1.15–4.68), high BMI (AOR = 2.91, 95% CI 1.49–5.71), and low hemoglobin (AOR = 3.38, 95% CI 2.00–7.46) were the factors associated with renal impairment during follow-up.

Conclusion

Impaired renal function was common in HIV-infected patients initiating ART in an outpatient setting in Ethiopia, and there appears to be a high prevalence of renal impairment after a median ART follow-up of 3 years. There is a need for assessment of renal function at baseline before ART initiation and regular monitoring of renal function for patients with HIV during follow-up.

HIV-Associated CKDs in Children and Adolescents

INTRODUCTION

Limited information is available describing the current prevalence of proteinuria and HIV-associated CKDs (HIV-CKDs) in children and adolescents living with HIV and receiving antiretroviral therapy in the United States.

METHODS

To address this issue, we performed a retrospective study of children and adolescents living with HIV who received medical care at Children's National Hospital in Washington, DC, between January 2012 and July 2019. Demographic data, clinical parameters (mode of HIV transmission, viral loads, CD4 cell counts, serum creatinine, glomerular filtration rate [GFR], plasma lipid levels, proteinuria, blood pressure, renal biopsies), and medical treatments, all done as a standard of clinical care, were collected and analyzed.

RESULTS

The majority of the 192 patients enrolled were of African descent (88%) and acquired HIV through vertical transmission (97%). The prevalence of all HIV-CKDs was 6%. Of these patients, 39% had intermittent or persistent proteinuria, and 7% percent had proteinuria with a mild decline in GFR (60-80 ml/min per 1.73 m2), and 6% had a mild decline in GFR without proteinuria. Documented hypertension was present in 6% of the patients, mainly in association with HIV-CKD. Patients with persistent proteinuria (3%) and biopsy-proven HIV-CKD had a slow but constant progression of their renal diseases.

CONCLUSIONS

The prevalence of persistent proteinuria and HIV-CKD was lower than that reported in previous studies conducted in the United States. However, intermittent proteinuria, mild reductions in GFR, and progression of established HIV-CKD were common findings in this group of patients with predominantly vertically acquired HIV who were receiving antiretroviral therapy.

Pharmacotherapeutic options for kidney disease in HIV positive patients

INTRODUCTION

Since the developmentof combined antiretroviral therapy (cART), HIV-associated mortality and the incidence of HIV-associated end-stage kidney disease (ESKD) has decreased. However, in the United States, an increase in non-HIV-associated kidney diseases within the HIV-positive population is expected.

AREAS COVERED

In this review, the authors highlight the risk factors for kidney disease within an HIV-positive population and provide the current recommendations for risk stratification and for the monitoring of its progression to chronic kidney disease (CKD), as well as, treatment. The article is based on literature searches using PubMed, Medline and SCOPUS.

EXPERT OPINION

The authors recommend clinicians (1) be aware of early cART initiation to prevent and treat HIV-associated kidney diseases, (2) be aware of cART side effects and discriminate those that may become more nephrotoxic than others and require dose-adjustment in the setting of eGFR ≤ 30ml/min/1.73m², (3) follow KDIGO guidelines regarding screening and monitoring for CKD with a multidisciplinary team of health professionals, (4) manage other co-infections and comorbidities, (5) consider changing cART if drug induced toxicity is established with apparent eGFR decline of ≥ 10ml/min/1.73m² or rising creatinine (≥0.5mg/dl) during drug-drug interactions, and (6) strongly consider kidney transplant in appropriately selected individuals with end stage kidney failure.

Treatment of parvovirus B19 viremia to facilitate kidney transplantation in a patient with collapsing glomerulopathy

Collapsing glomerulopathy (CG) is a severe form of glomerulopathy which results in nephrotic syndrome and often ensues in rapid progression to end-stage kidney disease (ESKD). Although most commonly a result of HIV infection, other conditions such as parvovirus B19 (PB19) infection have been associated with CG. We present a case of an 18-year-old male with CG associated with PB19 infection who was heterozygous for APOL1 G1 and G2 genetic variants. In an attempt to treat, he was started on intravenous immunoglobulin (IVIg), however rapidly progressed to ESKD. During workup for a living donor kidney transplant he was found to have persistent low-grade PB19 viremia. Despite having no major immunodeficiency and given subsequent courses of IVIg, viremia continued to persist. In a final attempt to eradicate the PB19 we began treatment with cidofovir, an antiviral agent with in vitro efficacy against PB19. Subsequent to initiation of cidofovir, PB19 viremia slowly cleared after which he received a living unrelated kidney transplant. The patient had an early cellular rejection treated with rabbit antithymocyte globulin after which he recovered kidney function without signs of recurrent CG. Our case report suggests efficacy of IVIg and cidofovir for persistent PB19 infection in ESKD to allow subsequent transplantation, while minimizing the risk of recurrent CG.

HIV, drugs and the kidney

Human immunodeficiency virus (HIV) affects over 36 million people worldwide. Antiretroviral therapy (ART) is expanding and improving HIV viral suppression, resulting in increasing exposure to drugs and drug interactions. Polypharmacy is a common complication as people are living longer on ART, increasing the risk of drug toxicities. Polypharmacy is related not only to ART exposure and medication for opportunistic infections, but also to treatment of chronic lifestyle diseases. Acute kidney injury (AKI) is frequent in HIV and is commonly the result of sepsis, dehydration and drug toxicities. Furthermore, HIV itself increases the risk of chronic kidney disease (CKD). Drug treatment is often complicated in people living with HIV because of a greater incidence of AKI and/or CKD compared to the HIV-negative population. Impaired renal function affects drug interactions, drug toxicities and importantly drug dosing, requiring dose adjustment. This review discusses ART and its nephrotoxic effects, including drug–drug interactions. It aims to guide the clinician on dose adjustment in the setting of renal impairment and dialysis, for the commonly used drugs in patients with HIV.

Effect of TDF-containing regimens on creatinine clearance in HIV patients in Namibia with a baseline CrCl <60ml/min; findings and implications

Background and aims: The advent of antiretroviral therapy (ART) and early diagnosis of the human immunodeficiency virus (HIV) has resulted in an appreciable reduction in morbidity and mortality among people infected with HIV. However, tenofovir disoproxil fumarate (TDF)-containing ART regimens are associated with a reduction in creatinine clearance (CrCl). No evaluation has been conducted in Namibia to date on the relationship between TDF-containing ART and CrCl among patients with moderate to severe reductions in CrCl to guide future practice. We aimed to address this.Methodology: Retrospective longitudinal study between January 2008 to December 2016 evaluating CrCl in patients with a baseline CrCl <60ml/min who were receiving TDF-containing ART in a leading hospital in Namibia. We identified patients who had experienced an improvement in CrCl and compared their characteristics with those whose CrCl did not improve. We assessed factors for an association with improvement in CrCl using binary logistic regression.Results: 389 patients were included, the majority were female (n = 294). Female vs. male assessments showed no difference in age (p = 0.340), weight (p = 0.920), number who experienced an improvement (105 vs 39, p = 0.349), or absence of improvement (189 vs. 56, p = 0.349). The improvement group (male and female) had a lower baseline CrCl (45.9 vs. 55.0, p < 0.001). The follow-up CrCl for the improvement and no improvement groups were 72.6 and 55.9 respectively. Multivariate analysis showed that the odds of improvement were: 0.905 (0.871-0.940, p < 0.001) for each unit rise in the baseline CrCl, and 0.904(0.880-0.923) for each year of follow-up.Conclusion: More improvement than decline in CrCl was observed. Improvement occurred more in patients with lower baseline CrCl, and occurred in the early period of ART with reduced odds of experiencing this with time. Our findings indicate that TDF may be used in patients with a low baseline CrCl.

The Changing Face of Human Immunodeficiency Virus-Mediated Kidney Disease

In nearly 40 years since human immunodeficiency virus (HIV) first emerged, much has changed. Our understanding of the pathogenesis of HIV infection and its effect on the cells within each kidney compartment has progressed, and the natural history of the disease has been transformed. What was once an acutely fatal illness is now a chronic disease managed with oral medications. This change is largely due to the advent of antiretroviral drugs, which have dramatically altered the prognosis and progression of HIV infection. However, the success of antiretroviral therapy has brought with it new challenges for the nephrologist caring for patients with HIV/acquired immune deficiency syndrome, including antiretroviral therapy-induced nephrotoxicity, development of non-HIV chronic kidney disease, and rising incidence of immune-mediated kidney injury. In this review, we discuss the pathogenesis of HIV infection and how it causes pathologic changes in the kidney, review the nephrotoxic effects of select antiretroviral medications, and touch upon other causes of kidney injury in HIV cases, including mechanisms of acute kidney injury, HIV-related immune complex glomerular disease, and thrombotic microangiopathy.

Drug interaction after ritonavir discontinuation: considerations for antiretroviral therapy changes in renal transplant recipients

Organ transplantation among people living with human immunodeficiency virus (PLHIV) is increasing. Guidelines recommend any changes in antiretroviral therapy (ART) prior to transplantation, but there are limited data regarding ART changes post transplantation. We report a case where an ART switch from a protease inhibitor-based regimen to dolutegravir plus emtricitabine/tenofovir alafenamide in a renal transplant recipient led to subtherapeutic tacrolimus concentrations and an increased serum creatinine (SCr). A workup for graft rejection was performed (including kidney biopsy and cytomegalovirus and BK virus polymerase chain reaction) following the rise in SCr, which was higher than expected from dolutegravir initiation (via organ cation transporter 2 inhibition). This case highlights the potential challenges of switching ART regimens in PLHIV post transplantation.

Autoimmune Kidney Diseases Associated with Chronic Viral Infections

Autoimmune kidney diseases triggered by viruses are an important cause of kidney disease in patients affected by chronic viral infection. Hepatitis B virus (HBV) infection is associated with membranous nephropathy and polyarteritis nodosa. Hepatitis C virus (HCV) infection is a major cause of cryoglobulinemic glomerulonephritis. Patients with human immunodeficiency virus (HIV) may develop HIV-associated nephropathy, a form of collapsing focal segmental glomerulosclerosis, or various forms of immune-complex-mediated kidney diseases. This article summarizes what is known about the pathogenesis, diagnosis, and management of immune-mediated kidney diseases in adults with chronic HBV, HCV, and HIV infections.

APOL1 Nephropathy: A Population Genetics and Evolutionary Medicine Detective Story

Common DNA sequence variants rarely have a high-risk association with a common disease. When such associations do occur, evolutionary forces must be sought, such as in the association of apolipoprotein L1 (APOL1) gene risk variants with nondiabetic kidney diseases in populations of African ancestry. The variants originated in West Africa and provided pathogenic resistance in the heterozygous state that led to high allele frequencies owing to an adaptive evolutionary selective sweep. However, the homozygous state is disadvantageous and is associated with a markedly increased risk of a spectrum of kidney diseases encompassing hypertension-attributed kidney disease, focal segmental glomerulosclerosis, human immunodeficiency virus nephropathy, sickle cell nephropathy, and progressive lupus nephritis. This scientific success story emerged with the help of the tools developed over the past 2 decades in human genome sequencing and population genomic databases. In this introductory article to a timely issue dedicated to illuminating progress in this area, we describe this unique population genetics and evolutionary medicine detective story. We emphasize the paradox of the inheritance mode, the missing heritability, and unresolved associations, including cardiovascular risk and diabetic nephropathy. We also highlight how genetic epidemiology elucidates mechanisms and how the principles of evolution can be used to unravel conserved pathways affected by APOL1 that may lead to novel therapies. The APOL1 gene provides a compelling example of a common variant association with common forms of nondiabetic kidney disease occurring in a continental population isolate with subsequent global admixture. Scientific collaboration using multiple experimental model systems and approaches should further clarify pathomechanisms further, leading to novel therapies.

HIV-associated nephropathy: links, risks and management

Despite the decreased incidence of human immunodeficiency virus (HIV)-associated nephropathy due to the widespread use of combined active antiretroviral therapy, it remains one of the leading causes of end-stage renal disease (ESRD) in HIV-1 seropositive patients. Patients usually present with low CD4 count, high viral load and heavy proteinuria, with the pathologic findings of collapsing focal segmental glomerulosclerosis. Increased susceptibility exists in individuals with African descent, largely due to polymorphism in APOL1 gene. Other clinical risk factors include high viral load and low CD4 count. Advanced kidney disease and nephrotic range proteinuria have been associated with progression to ESRD. Improvement in kidney function has been observed after initiation of combined active antiretroviral therapy. Other treatment options, when clinically indicated, are inhibition of the renin-angiotensin system and corticosteroids. Further routine management approaches for patients with chronic kidney disease should be implemented. In patients with progression to ESRD, kidney transplant should be pursued, provided that viral load control is adequate. Screening for the presence of kidney disease upon detection of HIV-1 seropositivity in high-risk populations is recommended.

Kidney disease in the setting of HIV infection: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

HIV-positive individuals are at increased risk for kidney disease, including HIV-associated nephropathy, noncollapsing focal segmental glomerulosclerosis, immune-complex kidney disease, and comorbid kidney disease, as well as kidney injury resulting from prolonged exposure to antiretroviral therapy or from opportunistic infections. Clinical guidelines for kidney disease prevention and treatment in HIV-positive individuals are largely extrapolated from studies in the general population, and do not fully incorporate existing knowledge of the unique HIV-related pathways and genetic factors that contribute to the risk of kidney disease in this population. We convened an international panel of experts in nephrology, renal pathology, and infectious diseases to define the pathology of kidney disease in the setting of HIV infection; describe the role of genetics in the natural history, diagnosis, and treatment of kidney disease in HIV-positive individuals; characterize the renal risk-benefit of antiretroviral therapy for HIV treatment and prevention; and define best practices for the prevention and management of kidney disease in HIV-positive individuals.

Chronic kidney disease incidence and survival of Thai HIV-infected patients

OBJECTIVES

As data on chronic kidney disease (CKD) incidence among Asian HIV patients has been limited, the present study aimed to estimate the CKD incidence in HIV-infected patients who received standard antiretroviral therapy in Thailand and to compare baseline demographics and clinical characteristics of the patients who developed CKD with those who do not.

DESIGN

A multicenter, observational prospective cohort of HIV patients with normal kidney functions who received standard antiretroviral therapy.

METHODS

CKD was diagnosed based on the KDIGO 2012 criteria, using Chronic Kidney Disease Epidemiology Collaboration based estimated glomerular filtration rate with and without urine protein. The cumulative probability of CKD incidence was analyzed using Kaplan-Meier estimation.

RESULTS

Of 5552 patients, 96 patients with pre-existing CKD and 26 patients with incomplete data were excluded, and 5430 patients were analyzed. Their mean age was 39.87 years, 41.52% were women, and 49.45% were homosexual. They were followed up for 49.41 months on average, with 229 incident cases (4.22%) being identified during 22 035 person-years at risk. Overall CKD incidence rate was 10.39 per 1000 person-years. Average time to CKD was 26.4 months (95% confidence interval: 24.44-28.83). The adjusted relative hazard significantly increased by 8.6% and 10.3% for each additional year of patient age and each additional log10 copies/ml of HIV viral load, respectively. Patients with diabetes mellitus and hypercholesterolemia had significantly higher adjusted relative hazard (3.37 and 1.41; P < 0.001 and P = 0.014), respectively.

CONCLUSION

CKD incidence among the Thai HIV-infected patients was lower than in white and non-Southeast Asian populations. Diabetes, hypercholesterolemia, age, and HIV viral load were the significant risk factors.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01328275.

Pharmacotherapy and treatment options for HIV-associated nephropathy

INTRODUCTION

Human immunodeficiency virus (HIV) remains a worldwide disease with significant mortality and morbidity. There are a multitude of HIV-related kidney diseases including HIV-associated nephropathy (HIVAN) most prominently. The risk of developing HIVAN increases with decreasing CD4 count, higher viral load, and based on genetic factors. The mortality rate for those with HIVAN-end stage renal disease (ESRD) remains 2.5-3 times higher than ESRD patients without HIVAN.

AREAS COVERED

The epidemiology of HIVAN, particularly risk assessment, will be explored in this review. Further, the pathogenesis of HIVAN, from viral-specific renal expression to the role of genetics as well as characteristic renal pathology will be described. Diagnosis and management of HIVAN will be addressed, with an emphasis on various treatment strategies including medication, dialysis, and kidney transplantation.

EXPERT OPINION

HIVAN is associated with a high risk for progression to ESRD and increased mortality. The backbone of HIVAN therapy remains combined anti-retroviral therapy (cART), while adjunctive therapies including RAAS blockade and prednisone, should be considered. In those who progress to ESRD, dialysis remains the mainstay of management, though increasing evidence has demonstrated that kidney transplantation can be effective in those with controlled HIV disease.

The evolving science of apolipoprotein-L1 and kidney disease

PURPOSE OF REVIEW

There are evolving epidemiological and biological data to support an association between the gene encoding apolipoprotein-L1 (APOL1) and progressive chronic kidney disease (CKD) among African-Americans.

RECENT FINDINGS

Individuals with two APOL1 risk alleles are at greater risk of incident albuminuria, CKD, and progression to end-stage renal disease despite optimal blood pressure management and use of angiotensin-converting enzyme inhibitors. These variants also appear to influence outcomes in donor and recipients in kidney transplantation. Recent studies have also variably shown a potential role of APOL1 variants in cardiovascular disease. A number of studies have addressed genetic and environmental factors such as HIV but most do not modify the course of APOL1-related kidney disease. Although the exact mechanism remains unclear, functional studies have demonstrated the effect of APOL1 and related protein on innate immunity and cytotoxicity.

SUMMARY

APOL1 is an important genetic risk factor for kidney disease among African-Americans. With approximately one in 10 African-Americans at risk, further studies are warranted to identify underlying biological mechanisms and other potential modifiers leading to CKD. Moreover, studies that clarify the association of APOL1 variants with cardiovascular disease, independent of CKD, are also needed.

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

Supplemental Digital Content is available in the text

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.

Podocytes

Podocytes are highly specialized cells of the kidney glomerulus that wrap around capillaries and that neighbor cells of the Bowman’s capsule. When it comes to glomerular filtration, podocytes play an active role in preventing plasma proteins from entering the urinary ultrafiltrate by providing a barrier comprising filtration slits between foot processes, which in aggregate represent a dynamic network of cellular extensions. Foot processes interdigitate with foot processes from adjacent podocytes and form a network of narrow and rather uniform gaps. The fenestrated endothelial cells retain blood cells but permit passage of small solutes and an overlying basement membrane less permeable to macromolecules, in particular to albumin. The cytoskeletal dynamics and structural plasticity of podocytes as well as the signaling between each of these distinct layers are essential for an efficient glomerular filtration and thus for proper renal function. The genetic or acquired impairment of podocytes may lead to foot process effacement (podocyte fusion or retraction), a morphological hallmark of proteinuric renal diseases. Here, we briefly discuss aspects of a contemporary view of podocytes in glomerular filtration, the patterns of structural changes in podocytes associated with common glomerular diseases, and the current state of basic and clinical research.

Differentiating HIV-associated nephropathy from antiretroviral drug-induced nephropathy: a clinical challenge

With the introduction of potent combination antiretroviral therapy (cART) into clinical practice, HIV-infected patients have garnered much benefit. However, kidney disease continues to be a potential complication in this group. Whereas HIV-associated nephropathy (HIVAN) was the major renal complication prior to cART, co-morbid diseases and adverse renal effects of various drugs, in particular cART, now complicate the landscape. Clinicians now must differentiate HIVAN from cART nephrotoxicity. While sometimes this is easy and relatively straightforward, often the clinician faces a difficult challenge distinguishing these two etiologies of kidney disease. This review will discuss HIVAN and cART-related kidney disease and review the clinical and laboratory data that may be useful in differentiating these processes. Often, however, kidney biopsy may be required to differentiate HIVAN from cART nephrotoxicity as well as other kidney lesions associated with concurrent co-morbidities, both infectious and non-infectious.

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.

The clinical characteristics and pathological patterns of postinfectious glomerulonephritis in HIV-infected patients

Background

Postinfectious glomerulonephritis (PIGN), a form of immune complex GN, is not well-defined in HIV-infected patients. This study characterizes PIGN in this patients’ population and determine the impact of histopathological patterns on renal outcome and mortality.

Methods

HIV-infected patients with PIGN from September 1998 to July 2013 were identified. Archived slides were reviewed by a blinded renal pathologist, classified into acute, persistent and healed PIGN. Groups were compared using Wilcoxon rank-sum and Fisher’s exact test. Survival analyses were performed to determine association of histopathological pattern with renal outcome and mortality.

Results

Seventy-two HIV-infected predominantly African American males were identified with PIGN. Median (interquartile range) age and creatinine at the time of renal biopsy was 48 years (41, 53) and 2.5 mg/dl (1.5, 4.9) respectively. Only 2 (3%) had acute PIGN, 42 (58%) had persistent PIGN and 28 (39%) had healed PIGN. Three patients (4%) had IgA-dominant PIGN. Only 46% of the patients had confirmed positive cultures with Staphylococcus the most common infectious agent. During a median follow up of 17 months, the pathological pattern had no impact on renal outcome (P = 0.95). Overall mortality was high occurring in 14 patients (19%); patients with healed PIGN had significantly increased mortality (P = 0.05).

Conclusion

In HIV-infected patients, Staphylococcus is the most common cause of PIGN. Renal outcome was not influenced by the histopathological pattern but those with healed PIGN had greater mortality which was potentially due to a confounder not accounted for in the study.

Screening for decreased glomerular filtration rate and associated risk factors in a cohort of HIV-infected patients in a middle-income country

With the introduction of combined active antiretroviral therapy and the improved survival of HIV-infected patients, degenerative diseases and drug toxicity have emerged as long-term concerns. We studied the prevalence of decreased glomerular filtration rate (GFR) and associated risk factors in a cohort of HIV-infected patients from a middle-income country. Our cross-sectional study included all adult patients who attended an urban outpatient clinic in 2008. GFR was estimated using the CKD-EPI equation. The prevalence ratio (PR) of decreased GFR (defined as <60 mL/min/1.73 m²) was estimated using generalizing linear models assuming a Poisson distribution. We analyzed data from 1,970 patients, of which 82.9% had been exposed to ART. A total of 249 patients (12.6%) had a GFR between 60 and 89 mL/min/1.73 m², 3.1% had a GFR between 30 and 59, 0.3% had a GFR between 15 and 29, and 0.4% had a GFR <15. Decreased GFR was found in only 74 patients (3.8%). In the multivariate regression model, the factors that were independently associated with a GFR below 60 mL/min/1.73 m² were as follows: age ≥50 years (PR = 3.4; 95% CI: 1.7–6.8), diabetes (PR = 2.0; 95% CI: 1.2–3.4), hypertension (PR = 2.0; 95% CI: 1.3–3.2), current CD4+ cell count <350 cells/mm3 (PR = 2.1; 95% CI: 1.3–3.3), past exposure to tenofovir (PR = 4.7; 95% CI: 2.3–9.4) and past exposure to indinavir (PR = 1.7; 95% CI: 1.0–2.8). As in high-income countries, CKD was the predominant form of kidney involvement among HIV-infected individuals in our setting. The risk factors associated with decreased glomerular filtration were broad and included virus-related factors as well as degenerative and nephrotoxic factors. Despite the potential for nephrotoxicity associated with some antiretroviral drugs, in the short-term, advanced chronic renal disease remains very rare.

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.

Impact of antiretroviral therapy on renal function among HIV-infected Tanzanian adults: a retrospective cohort study

Background

Data regarding the outcomes of HIV-infected adults with baseline renal dysfunction who start antiretroviral therapy are conflicting.

Methods

We followed up a previously-published cohort of HIV-infected adult outpatients in northwest Tanzania who had high prevalence of renal dysfunction at the time of starting antiretroviral therapy (between November 2009 and February 2010). Patients had serum creatinine, proteinuria, microalbuminuria, and CD4⁺ T-cell count measured at the time of antiretroviral therapy initiation and at follow-up. We used the adjusted Cockroft-Gault equation to calculate estimated glomerular filtration rates (eGFRs).

Results

In this cohort of 171 adults who had taken antiretroviral therapy for a median of two years, the prevalence of renal dysfunction (eGFR <90 mL/min/1.73 m²) decreased from 131/171 (76.6%) at the time of ART initiation to 50/171 (29.2%) at the time of follow-up (p<0.001). Moderate dysfunction (eGFR<60 mL/min/1.73 m²) decreased from 21.1% at antiretroviral therapy initiation to 1.1% at follow-up (p<0.001), as did the prevalence of microalbuminuria (72% to 44%, p<0.001). Use of tenofovir was not associated with renal dysfunction at follow-up.

Conclusion

Mild and moderate renal dysfunction were common in this cohort of HIV-infected adults initiating antiretroviral therapy, and both significantly improved after a median follow-up time of 2 years. Our work supports the renal safety of antiretroviral therapy in African adults with mild-moderate renal dysfunction, suggesting that these regimens do not lead to renal damage in the majority of patients and that they may even improve renal function in patients with mild to moderate renal dysfunction.

[HIV-associated nephropathy with amoebic enteritis: a case report and literature review]

We herein describe a case of HIV-associated nephropathy (HIVAN) in a 64-year-old HIV antibody-positive man presenting with proteinuria. Laboratory examinations showed positive proteinuria, a high β2-microglobulin level and decreased creatinine clearance. He underwent a percutaneous renal biopsy, and a pathologic evaluation revealed a collapsing form of focal sclerosing glomerulosclerosis. Histologically, HIVAN is a collapsing form of focal sclerosing glomerulosclerosis (FSGS), which can be distinguished from idiopathic FSGS by the presence of microcystic tubular dilatation and interstitial inflammation. The patient was diagnosed with HIV-associated nephropathy and was started on ART. The HIV-associated nephropathy did not progress to acute renal failure, and long-term survival has been observed for over 12 years.

Prevalence and risk factors for chronic kidney disease among HIV-infected antiretroviral therapy-naïve patients in mainland China: a multicenter cross-sectional study

AIM

The aim of the study was to evaluate the prevalence and risk factors of chronic kidney disease (CKD) among HIV-infected antiretroviral therapy (ART)-naïve patients in Mainland China.

METHODS

In this multicenter cross-sectional study, glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease (MDRD) equation. CKD was defined as GFRMDRD  < 60 mL/min per 1.73 m(2) and/or isolated proteinuria (≥1 + on urine dipstick) that persisted at month 3 after the baseline assessment. Risk factors associated with CKD were examined using univariate analysis and multivariate logistic regression analysis.

RESULTS

In total, 538 HIV-infected ART-naïve patients were included in this study. There were 399 male and 139 female patients. The mean age was 36.5 ± 10.0 years. The prevalence of hypertension, glycometabolism abnormities, and CKD were 3.2%, 3.0%, and 16.1%, respectively. Thirteen (2.4%) patients had estimated GFR (eGFR) < 60 mL/min per 1.73 m(2), while 73 (13.7%) patients had proteinuria. Using univariate analysis, CKD was found to be significantly (P < 0.05) associated with age, hypertension, HCV co-infection, and plasma HIV-1 viral load ≥ 100 000 copies/mL. In the multivariate logistic regression model, older age (increased by an interval of 10 years; P = 0.002), HCV co-infection (P = 0.039), and plasma HIV-1 viral load ≥ 100 000 copies/mL (P = 0.011) were significantly associated with CKD.

CONCLUSION

The incidence of CKD is high in Chinese HIV-infected ART-naïve patients. Traditional risk factors for renal disease, such as advancing age, HCV co-infection, and higher plasma viral load were correlated with CKD in the present patient samples.

Late presentation to HIV/AIDS testing, treatment or continued care: clarifying the use of CD4 evaluation in the consensus definition

OBJECTIVES

Late presentation to HIV/AIDS services compromises treatment outcomes and misses opportunities for biomedical and behavioural prevention. There has been significant heterogeneity in how the term 'late presentation' (LP) has been used in the literature. In 2011, a consensus definition was reached using CD4 counts to define and measure late presenters and, while it is useful for clinical care, the consensus definition has several important limitations that we discuss in this article.

METHODS

Using the spectrum of engagement in HIV care presented by Gardner and colleagues, this article highlights issues and opportunities associated with use of the consensus definition.

RESULTS

The consensus definition is limited by three principal factors: (1) the CD4 count threshold of 350 cells/μL is being increasingly questioned as the biomedical justification grows for earlier initiation of treatment; (2) CD4 evaluations are conducted at multiple services providing HIV care; thus it remains unclear to which service the patient is presenting late; and (3) the limited availability of CD4 evaluation restricts its use in determining the prevalence of LP in many settings.

CONCLUSIONS

The consensus definition is useful because it describes the level of disease progression and allows for consistent evaluation of the prevalence and determinants of LP. Suggestions are provided for improving the application of the consensus definition in future research.

Comparison of risk factors and outcomes in HIV immune complex kidney disease and HIV-associated nephropathy

BACKGROUND AND OBJECTIVES

HIV-associated nephropathy (HIVAN) is well described, but the clinical features of a group of renal pathologies characterized by Ig or immune complex depositions referred to as HIV-associated immune complex kidney disease (HIVICK) have not been well established. The objective of this study is to assess risk factors for HIVICK compared with contemporaneous control participants.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A nested case-control study of 751 HIV-infected patients followed from January 1996 to June 2010 was conducted. Groups were compared using the chi-squared test or rank-sum analysis. Conditional logistic regression was used to estimate odds ratios (ORs) for HIVICK. Incidences of overall ESRD and with/without combined antiretroviral therapy (cART) exposure were calculated.

RESULTS

HIVICK patients were predominantly African American (92%). Compared with matched controls, patients with HIVICK were more likely to have HIV RNA >400 copies/ml (OR, 2.5; 95% confidence interval [95% CI], 1.2 to 5.2), diabetes (OR, 2.8; 95% CI, 1.1 to 6.8), and hypertension (OR, 2.3; 95% CI, 1.2 to 4.5). Compared with HIVAN, patients with HIVICK had more antiretroviral therapy exposure, lower HIV viral loads, and higher CD4 and estimated GFR. ESRD was less common in the HIVICK versus the HIVAN group (30% versus 82%; P<0.001), and the use of cART was not associated with ESRD in HIVICK patients (25% versus 26; P=0.39).

CONCLUSIONS

HIVICK was predominantly observed in African-American patients and associated with advanced HIV disease. ESRD incidence is lower in HIVICK patients compared with those with HIVAN. Unlike HIVAN, cART use was not associated with the incidence of ESRD in HIVICK.

Antiretroviral-treated HIV-infected women have similar long-term kidney function trajectories as HIV-uninfected women

Natural history studies suggest increased risk for kidney function decline with HIV infection, but few studies have made comparisons with HIV-uninfected women. We examined whether HIV infection treated with highly active antiretroviral therapy (HAART) remains associated with faster kidney function decline in the Women's Interagency HIV Study. HIV-infected women initiating HAART with (n=105) or without (n=373) tenofovir (TDF) were matched to HIV-uninfected women on calendar and length of follow-up, age, systolic blood pressure, hepatitis C antibody serostatus, and diabetes history. Linear mixed models were used to evaluate differences in annual estimated glomerular filtration rate (eGFR). Person-visits were 4,741 and 11,512 for the TDF-treated and non-TDF-treated analyses, respectively. Mean baseline eGFRs were higher among women initiated on TDF-containing HAART and lower among those on TDF-sparing HAART compared to their respective HIV-uninfected matches (p<0.05 for both). HIV-infected women had annual rates of eGFR changes similar to HIV-uninfected matches (p-interaction >0.05 for both). Adjusting for baseline eGFR, mean eGFRs at 1 and 3 years of follow-up among women initiated on TDF-containing HAART were lower than their uninfected matches (-4.98 and -4.26 ml/min/1.73 m(2), respectively; p<0.05 for both). Mean eGFR of women initiated on TDF-sparing HAART was lower versus uninfected matches at 5 years (-2.19 ml/min/1.73 m(2), p=0.03). HAART-treated HIV-infected women had lower mean eGFRs at follow-up but experienced rates of annual eGFR decline similar to HIV-uninfected women. Tenofovir use in HIV-infected women with normal kidney function did not accelerate long-term kidney function decline relative to HIV-uninfected women.

Proteinuria in paediatric patients with human immunodeficiency virus infection

In human immunodeficiency virus (HIV)-infected people kidney disease is as an important cause of morbidity and mortality. Clinical features of kidney damage in HIV-infected patients range from asymptomatic microalbuminuria to nephrotic syndrome. The lack of specific clinical features despite the presence of heavy proteinuria may mask the renal involvement. Indeed, it is important in HIV patients to monitor renal function to early discover a possible kidney injury. After the introduction of antiretroviral therapy, mortality and morbidity associated to HIV-infection have shown a substantial reduction, although a variety of side effects for long-term use of highly active antiretroviral therapy, including renal toxicity, has emerged. Among more than 20 currently available antiretroviral agents, many of them can occasionally cause reversible or irreversible nephrotoxicity. At now, three antiretroviral agents, i.e., indinavir, atazanavir and tenofovir disoproxil fumarate have a well established association with direct nephrotoxicity. This review focuses on major causes of proteinuria and other pathological findings related to kidney disease in HIV-infected children and adolescents.

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.

Renal dysfunction in the setting of HIV/AIDS

Antiretroviral therapy has been immensely successful in reducing the incidence of opportunistic infections and death after HIV infection. This has resulted in heightened interest in noninfectious comorbidities including kidney disease. Although HIV-associated nephropathy, the most ominous kidney disease related to the direct effects of HIV, may be prevented and treated with antiretrovirals, kidney disease remains an important issue in this population. In addition to the common risk factors for kidney disease of diabetes mellitus and hypertension, HIV-infected individuals have a high prevalence of other risk factors, including hepatitis C and exposure to antiretrovirals and other medications. Therefore, the differential diagnosis is vast. Early identification (through efficient screening) and prompt treatment of kidney disease in HIV-infected individuals are critical to lead to better outcomes. This review focuses on clinical and epidemiological issues, treatment strategies (including dialysis and kidney transplantation), and recent advances among kidney disease in the HIV population.

End-stage renal disease and dialysis in HIV-positive patients: observations from a long-term cohort study with a follow-up of 22 years

OBJECTIVES

Renal disease is a common and serious complication in HIV-infected patients.

METHODS

A retrospective cohort analysis for the period 1989-2010 was carried out to determine the prevalence, incidence and risk factors for end-stage renal disease (ESRD). ESRD was defined as initiation of renal replacement therapy. Three time periods were defined: 1989-1996 [pre-highly active antiretroviral therapy (HAART)], 1997-2003 (early HAART) and 2004-2010 (late HAART).

RESULTS

Data for 9198 patients [78.2% male; 88.9% Caucasian; cumulative observation time 68 084 patient-years (PY)] were analysed. ESRD was newly diagnosed in 35 patients (0.38%). Risk factors for ESRD were Black ethnicity [relative risk (RR) 5.1; 95% confidence interval (CI) 2.3-10.3; P < 0.0001], injecting drug use (IDU) (RR 2.3; 95% CI 1.1-4.6; P = 0.02) and hepatitis C virus (HCV) coinfection (RR 2.2; 95% CI 1.1-4.2; P = 0.03). The incidence of ESRD decreased in Black patients over the three time periods [from 788.8 to 130.5 and 164.1 per 100 000 PY of follow-up (PYFU), respectively], but increased in Caucasian patients (from 29.9 to 41.0 and 43.4 per 100 000 PYFU, respectively). The prevalence of ESRD increased over time and reached 1.9 per 1000 patients in 2010. Mortality for patients with ESRD decreased nonsignificantly from period 1 to 2 (RR 0.72; P = 0.52), but significantly from period 1 to 3 (RR 0.24; P = 0.006), whereas for patients without ESRD mortality decreased significantly for all comparisons. ESRD was associated with a high overall mortality (RR 9.9; 95% CI 6.3-14.5; P < 0.0001).

CONCLUSION

As a result of longer survival, the prevalence of ESRD is increasing but remains associated with a high mortality. The incidence of ESRD declined in Black but not in Caucasian patients. IDU and HCV were identified as additional risk factors for the development of ESRD.

Total protein, albumin and low-molecular-weight protein excretion in HIV-positive patients

BACKGROUND

Chronic kidney disease is common in HIV positive patients and renal tubular dysfunction has been reported in those receiving combination antiretroviral therapy (cART). Tenofovir (TFV) in particular has been linked to severe renal tubular disease as well as proximal tubular dysfunction. Markedly elevated urinary concentrations of retinal-binding protein (RBP) have been reported in patients with severe renal tubular disease, and low-molecular-weight proteins (LMWP) such as RBP may be useful in clinical practice to assess renal tubular function in patients receiving TFV. We analysed 3 LMWP as well as protein and albumin in the urine of a sample of HIV positive patients.

METHODS

In a cross-sectional fashion, total protein, albumin, RBP, cystatin C, and neutrophil gelatinase-associated lipocalin (NGAL) were quantified in random urine samples of 317 HIV positive outpatients and expressed as the ratio-to-creatinine (RBPCR, CCR and NGALCR). Exposure to cART was categorised as none, cART without TFV, and cART containing TFV and a non-nucleoside reverse-transcriptase-inhibitor (TFV/NNRTI) or TFV and a protease-inhibitor (TFV/PI).

RESULTS

Proteinuria was present in 10.4 % and microalbuminuria in 16.7 % of patients. Albumin accounted for approximately 10 % of total urinary protein. RBPCR was within the reference range in 95 % of patients while NGALCR was elevated in 67 % of patients. No overall differences in urine protein, albumin, and LMWP levels were observed among patients stratified by cART exposure, although a greater proportion of patients exposed to TFV/PI had RBPCR >38.8 μg/mmol (343 μg/g) (p = 0.003). In multivariate analyses, black ethnicity (OR 0.43, 95 % CI 0.24, 0.77) and eGFR <75 mL/min/1.73 m2 (OR 3.54, 95 % CI 1.61, 7.80) were independently associated with upper quartile (UQ) RBPCR. RBPCR correlated well to CCR (r2 = 0.71), but not to NGALCR, PCR or ACR.

CONCLUSIONS

In HIV positive patients, proteinuria was predominantly of tubular origin and microalbuminuria was common. RBPCR in patients without overt renal tubular disease was generally within the reference range, including those receiving TFV. RBP therefore appears a promising biomarker for monitoring renal tubular function in patients receiving TFV and for distinguishing patients with normal tubular function or mild tubular dysfunction from those with severe renal tubular disease or Fanconi syndrome.

Considerations in the rationale, design and methods of the Strategic Timing of AntiRetroviral Treatment (START) study

BACKGROUND

Untreated human immunodeficiency virus (HIV) infection is characterized by progressive depletion of CD4+ T lymphocyte (CD4) count leading to the development of opportunistic diseases (acquired immunodeficiency syndrome (AIDS)), and more recent data suggest that HIV is also associated with an increased risk of serious non-AIDS (SNA) diseases including cardiovascular, renal, and liver diseases and non-AIDS-defining cancers. Although combination antiretroviral treatment (ART) has resulted in a substantial decrease in morbidity and mortality in persons with HIV infection, viral eradication is not feasible with currently available drugs. The optimal time to start ART for asymptomatic HIV infection is controversial and remains one of the key unanswered questions in the clinical management of HIV-infected individuals.

PURPOSE

In this article, we outline the rationale and methods of the Strategic Timing of AntiRetroviral Treatment (START) study, an ongoing multicenter international trial designed to assess the risks and benefits of initiating ART earlier than is currently practiced. We also describe some of the challenges encountered in the design and implementation of the study and how these challenges were addressed.

METHODS

A total of 4000 study participants who are HIV type 1 (HIV-1) infected, ART naïve with CD4 count > 500 cells/µL are to be randomly allocated in a 1:1 ratio to start ART immediately (early ART) or defer treatment until CD4 count is <350 cells/µL (deferred ART) and followed for a minimum of 3 years. The primary outcome is time to AIDS, SNA, or death. The study had a pilot phase to establish feasibility of accrual, which was set as the enrollment of at least 900 participants in the first year.

RESULTS

Challenges encountered in the design and implementation of the study included the limited amount of data on the risk of a major component of the primary endpoint (SNA) in the study population, changes in treatment guidelines when the pilot phase was well underway, and the complexities of conducting the trial in a geographically wide population with diverse regulatory requirements. With the successful completion of the pilot phase, more than 1000 participants from 100 sites in 23 countries have been enrolled. The study will expand to include 237 sites in 36 countries to reach the target accrual of 4000 participants.

CONCLUSIONS

START is addressing one of the most important questions in the clinical management of ART. The randomization provided a platform for the conduct of several substudies aimed at increasing our understanding of HIV disease and the effects of antiretroviral therapy beyond the primary question of the trial. The lessons learned from its design and implementation will hopefully be of use to future publicly funded international trials.