Involvement of the kidney in children and adolescents with perinatal (HIV-1) infection can occur at any stage during the child's life with diverse diagnoses, ranging from acute kidney injury, childhood urinary tract infections (UTIs), electrolyte imbalances and drug-induced nephrotoxicity, to diseases of the glomerulus. The latter include various immune-mediated chronic kidney diseases (CKD) and HIV-associated nephropathy (HIVAN).
The introduction of highly active anti-retroviral therapy (HAART) has dramatically reduced the incidence of HIVAN, once the commonest form of CKD in children of African descent living with HIV, and also altered its prognosis from eventual progression to end-stage kidney disease to one that is compatible with long-term survival. The impact of HAART on the outcome of other forms of kidney diseases seen in this population has not been as impressive. Increasingly important is nephrotoxicity secondary to the prolonged use of anti-retroviral agents, and the occurrence of co-morbid kidney disease unrelated to HIV infection or its treatment. Improved understanding of the molecular pathogenesis and genetics of kidney diseases associated with HIV will result in better screening, prevention and treatment efforts, as HIV specialists and nephrologists coordinate clinical care of these patients. Both haemodialysis (HD) and peritoneal dialysis (PD) are effective as renal replacement therapy in HIV-infected patients with end-stage kidney disease, with PD being preferred in resource-limited settings. Kidney transplantation, once contraindicated in this population, has now become the most effective renal replacement therapy, provided rigorous criteria are met. Given the attendant morbidity and mortality in HIV-infected children and adolescents with kidney disease, routine screening for kidney disease is recommended where resources permit.
This review focuses on the pathogenesis and genetics, clinical presentation and management of kidney disease in children and adolescents with perinatal HIV-1 infection.
human immunodeficiency virus; kidney; children; adolescents; anti-retroviral drug toxicity
Highly active antiretroviral therapy (HAART) and other medical therapies for HIV-related infections have been associated with toxicities. Antiretroviral therapy can contribute to renal dysfunction directly by inducing acute tubular necrosis, acute interstitial nephritis, crystal nephropathy, and renal tubular disorders or indirectly via drug interactions. With the increase in HAART use, clinicians must screen patients for the development of kidney disease especially if the regimen employed increases risk of kidney injury. It is also important that patients with chronic kidney disease (CKD) are not denied the best combinations, especially since most drugs can be adjusted based on the estimated GFR. Early detection of risk factors, systematic screening for chronic causes of CKD, and appropriate referrals for kidney disease management should be advocated for improved patient care. The interaction between immunosuppressive therapy and HAART in patients with kidney transplants and the recent endorsement of tenofovir/emtricitabine by the Centers for Disease Control (CDC) for preexposure prophylaxis bring a new dimension for nephrotoxicity vigilance. This paper summarizes the common antiretroviral drugs associated with nephrotoxicity with particular emphasis on tenofovir and protease inhibitors, their risk factors, and management as well as prevention strategies.
Importance of the field
Human immunodeficiency virus (HIV) infection is associated with the development of a wide spectrum of kidney diseases. HIV-associated nephropathy (HIVAN) is the most common cause of chronic kidney disease (CKD) in HIV-infected individuals and predominantly affects patients of African ancestry. HIVAN is a leading cause of end-stage renal disease (ESRD) among African-Americans.
Areas covered in this review
an overview of the spectrum of kidney disease in patients with HIV; current pharmacologic interventions to treat kidney disease in HIV.
What the reader will gain
Knowledge regarding the most common causes of kidney disease in HIV-infected patients and principals related to pharmacotherapy in HIV-infected patients with kidney disease.
Take home message
Kidney disease is an important cause of morbidity and mortality in HIV-infected patients and the most common cause of chronic kidney disease in this population is HIV-associated nephropathy, which is caused by viral infection of the renal epithelium. Several medications that are commonly used in HIV-infected patients can have adverse effects on the kidneys and the doses of many antiretroviral medications need to be adjusted in patients with impaired renal function.
HIV associated nephropathy; HIVAN; collapsing glomerulopathy; FSGS; antiretroviral therapy
Purpose of Review
Highly Active Antiretroviral Therapy (HAART) has resulted in a marked decrease in AIDS-related conditions and death. With improved survival, cardiovascular disease (CVD), hepatic, renal disease and non-AIDS related cancers represent an increasing burden for HIV infected individuals.
HIV Associated Nephropathy (HIVAN), acute renal injury, HAART, and co-morbid conditions such as Hepatitis C, hypertension and diabetes are among the multiple causes of renal disease. In HIVAN there is incomplete understanding of the interaction of the virus with renal cellsand the host genetics leading to susceptibility to this form of renal dysfunction. There is agreement that a baseline estimate of glomerular filtration (eGFR) should be obtained and that renal function should be monitored during antiretroviral therapy. There is, however no agreement as to the most accurate method of estimating GFR. Renal transplantation has emerged as a feasible and successful modality of management of end stage renal disease (ESRD) in HIV infected individuals.
Kidney disease represents an increasing concern in the care of HIV infected persons although there are questions remaining regarding the pathophysiology of HIVAN. Transplantation, however, can be carried out safely in infected persons with ESRD.
HIV Associated Nephropathy; Estimates of Glomerular filtration; Renal transplantation of HIV infected patients with end stage renal disease; Effects of anitiretroviral drugs upon renal function
Although kidney disease has been a recognized complication of HIV infection since the beginning of the HIV epidemic, its epidemiology, underlying causes and treatment have evolved in developed countries where HAART has been widely available. HIV-associated nephropathy and HIV immune complex-mediated kidney disease were the prominent renal diagnoses in the earlier period of the HIV epidemic. While HIV immune complex-mediated kidney disease remains a common finding among HIV-infected individuals with kidney disease, the incidence of HIV-associated nephropathy has been diminishing in developed countries. The role of the metabolic effects of long-term HAART exposure and nephrotoxicity of certain antiretroviral medications on the development and progression of chronic kidney disease is now of increasing concern. The long-term clinical implications of acute kidney injury among HIV-infected persons are increasingly recognized. Kidney disease in HIV-infected persons continues to be a major risk factor for morbidity and mortality in this patient population; therefore, early recognition and treatment of kidney disease are imperative in lessening the impact of kidney disease on the health of HIV-infected individuals. This review focuses on recent developments and ongoing challenges in the understanding, diagnosis and management of HIV-related kidney disease.
glomerular filtration rate; HIV; HIVAN; kidney disease; serum creatinine; tenofovir
Childhood HIV-1 associated nephropathy (HIVAN) is a clinical and renal histological disease characterized by heavy proteinuria associated with focal and segmental glomerular sclerosis and/or mesangial hyperplasia in combination with microcystic tubular dilatation. These lesions lead to renal enlargement and rapid progression to kidney failure. Children of African ancestry have a unique susceptibility to developing HIVAN. It is estimated that approximately 300,000 HIV-infected children living in the sub-Saharan Africa could develop HIVAN if they do not receive appropriate antiretroviral therapy. This article discusses recent developments and controversies related to the pathogenesis of childhood HIVAN. The role of host genetic factors, including the newly identified variants in the APOL1 gene, is discussed in the context of previous studies that established the pathological paradigm for HIVAN, and our current understanding of the functional genomics analysis. Hopefully, these advances will provide new research opportunities to generate better treatments for children with HIVAN.
African–American; APOL1; autophagic cell death; autophagy; Duffy antigen; genetic susceptibility; HIVAN; kidney failure; nonsynonymous SNP
In the early highly active antiretroviral therapy (HAART) era, kidney dysfunction was strongly associated with death among HIV-infected individuals. We re-examined this association in the later HAART period to determine whether chronic kidney disease (CKD) remains a predictor of death after HAART-initiation.
To evaluate the effect of kidney function at the time of HAART initiation on time to all-cause mortality, we evaluated 1415 HIV-infected women initiating HAART in the Women’s Interagency HIV Study (WIHS). Multivariable proportional hazards models with survival times calculated from HAART initiation to death were constructed; participants were censored at the time of the last available visit or December 31, 2006.
CKD (eGFR <60 ml/min/1.73 m2) at HAART initiation was associated with higher mortality risk adjusting for age, race, hepatitis C serostatus, AIDS history and CD4+ cell count (hazard ratio [HR]=2.23, 95% confidence interval [CI]: 1.45–3.43). Adjustment for hypertension and diabetes history attenuated this association (HR=1.89, CI: 0.94–3.80). Lower kidney function at HAART initiation was weakly associated with increased mortality risk in women with prior AIDS (HR=1.09, CI: 1.00–1.19, per 20% decrease in eGFR).
Kidney function at HAART initiation remains an independent predictor of death in HIV-infected individuals, especially in those with a history of AIDS. Our study emphasizes the necessity of monitoring kidney function in this population. Additional studies are needed to determine mechanisms underlying the increased mortality risk associated with CKD in HIV-infected persons.
kidney disease; mortality; HIV; WIHS; antiretroviral therapy
Direct effects of HIV-1 infection on the kidney combine with immune and genetic factors, comorbidities, coinfections, and medication toxicities to induce a spectrum of kidney disorders in HIV disease. The most dramatic of these, HIV associated nephropathy (HIVAN), emerges almost exclusively in persons of African descent and is associated with rapid progression to end-stage renal disease in the absence of antiretroviral therapy (ART). ART modifies the natural history of HIVAN, but the renal benefits of ART may not be limited to HIVAN. ART is often under prescribed or incorrectly dosed in persons with kidney disease, and kidney disease is a marker of accelerated HIV disease progression. Vigilant attention to kidney function and an understanding of the complex associations involving the kidneys is necessary for optimal care of these patients.
Human immunodeficiency virus-associated nephropathy (HIVAN) is a leading cause of end-stage renal disease in African Americans. The HIV-1 virus infects podocytes, cells integral to formation of the glomerular filtration barrier, often leading to focal segmental glomerulosclerosis. HIVAN is typically a complication of late-stage HIV infection, associated with low CD4 cell counts and elevated serum HIV RNA levels. Highly active antiretroviral therapy (HAART) is partially protective and has altered the natural history of HIV-associated kidney disease. Nonetheless, HIVAN remains an important public health concern among HIV-infected African Americans. Although polymorphisms in the MYH9 gene on chromosome 22 are strongly associated with HIVAN, as well as with idiopathic focal segmental glomerulosclerosis and global glomerulosclerosis (historically labeled "hypertensive nephrosclerosis"), the majority of HIV-infected patients who are genetically at risk from MYH9 do not appear to develop severe kidney disease. Therefore, we postulate that additional environmental exposures and/or inherited factors are necessary to initiate human HIVAN. Gene-environment interactions have also been proposed as necessary for initiation of HIVAN in murine models. It is important that these novel risk factors be identified, as prevention of environmental exposures and targeting of additional gene products may reduce the risk for HIVAN, even among those harboring two risk alleles in MYH9.
African Americans; FSGS; HIV-associated nephropathy; kidney disease; MYH9
HIV associated nephropathy (HIVAN) is the most common form of chronic kidney disease resulting directly from HIV infection. The true prevalence of HIVAN in the paediatric population of West Africa is unknown, largely due to lack of surveillance and reporting of kidney disease in HIV positive patients.
This was a prospective study over a six month period( July to December 2008) conducted in the Infectious Disease Unit of the Department of Paediatrics, University of Uyo Teaching Hospital, Uyo, Nigeria involving all confirmed cases of paediatric HIV infection. Urine microalbuminuria using calculated urine albumin – creatinine ratio was determined and repeated in 4 weeks interval. CD4 count and renal ultrasonography was done for all the patients. The correlation of urine albumin – creatinine ratio with CD4 count, duration of treatment with highly active antiretroviral therapy (HAART) and association with clinical staging of the disease was also examined.
Fifty – nine (60.2%) were males, thirty – nine (39.8%) were females with male to female ratio of 1.5:1. The prevalence rate of 31.6% HIVAN was found, out of which 3.1% had abnormal ultrasound findings. There was a significant correlation between CD4 count and urine albumin – creatinine ratio (r=−0.22, p=0.03). There was no correlation between urine albumin – creatinine ratio and duration on HAART (r=−0.10, p=0.31).
Screening for microalbuminuria is essential for the early diagnosis and treatment of HIVAN in this age group.
HIVAN; microalbuminuria; HIV; HAART; proteinuria; paediatrics; Nigeria
This study describes the incidence, clinical and demographic characteristics, and spectrum of chronic kidney disease (CKD) in youths with perinatal HIV-1 infection.
Retrospective analysis between May 1993 and December 2006 of subjects with renal disease followed in the Pediatric AIDS Clinical Trials Group 219/219C multicenter study examining long-term consequences of perinatal HIV infection. Diagnosis confirmation was made utilizing a questionnaire mailed to research sites. Participants with CKD of other etiology than HIV were excluded. Outcome measures were biopsy-diagnosed CKD and, in absence of biopsy, HIV-associated nephropathy (HIVAN) using established clinical criteria.
Questionnaires on 191 of 2,102 participants identified 27 cases of CKD: 14 biopsy-diagnosed and six clinical cases of HIVAN, and seven biopsy-diagnosed cases of immune complex-mediated kidney disease (lupus-like nephritis, three; IgA nephropathy, two; membranous nephropathy, two). Incidence rates for CKD associated with HIV in pre-HAART (1993–1997) and HAART (1998–2002, 2003–2006) eras were 0.43, 2.84 and 2.79 events per 1000 person years, respectively. In multivariable analysis, Black race and viral load ≥ 100,000 copies/ml (rate ratios 3.28 and 5.05, p ≤ 0.02) were associated with CKD.
A variety of immune complex-mediated glomerulonephritides and HIVAN occurs in this population. Black race and uncontrolled viral replication are risk factors for CKD associated with HIV.
HIVAN; HIV immune complex kidney disease; FSGS; renal; youth; proteinuria; biopsy
Antiretroviral therapy (ART) preserves kidney function in patients with human immunodeficiency virus (HIV)-associated nephropathy (HIVAN). Emerging data also document substantial renal benefits of ART in the general HIV-infected population, which is associated in part with suppression of HIV-1 viral replication. The extent to which the response to ART differs in persons with HIVAN, compared to those with other HIV-associated kidney disorders, is unknown. Beneficial effects of corticosteroids and angiotensin-converting enzyme (ACE) inhibitors on kidney function also are suggested by retrospective cohort studies and uncontrolled trials of patients with HIVAN. Underexposure to ART, or inadequate ART dosing in HIV-infected patients with CKD, may curtail the optimal benefits that may be derived from this therapy.
antiretroviral therapy; HIVAN; angiotensin-converting enzyme inhibitors; prednisone; chronic kidney disease
Highly active antiretroviral therapy (HAART) has significantly improved the prognosis for many individuals with HIV infection. Consequently, HIV infection has become a chronic and manageable disease. The focus on long-term management of patients with HIV infection has broadened to include comorbid conditions, most notably cardiovascular disease. Patients with HIV infection share many cardiovascular risk factors with the general population, and HIV infection itself may increase cardiovascular risk. Changes in lipid profiles associated with increased cardiovascular risk that have been observed with some HAART regimens have been a cause for concern among clinicians who treat HIV-infected patients. However, the lipid effects of HAART seem to depend on the type and duration of regimens employed. They can be managed effectively according to current guidelines that recommend lifestyle changes (eg, improved diet, increased exercise, smoking cessation) and pharmacologic therapy described in established treatment paradigms for patients on antiretroviral therapy and similar to measures currently used by the general population. A review of the clinical data indicates that the virologic and immunologic benefits of HAART clearly outweigh any metabolic effects observed in some patients over time and that preexisting, established cardiovascular risk factors contribute significantly to the potential development of cardiovascular events.
These benefits of antiretroviral therapy have been demonstrated in studies comparing the superior efficacy of continuous vs. intermittent HAART.
antiretroviral; cardiovascular; cholesterol; HAART; lopinavir; protease inhibitor; triglycerides
HIV-associated nephropathy (HIVAN) is a clinicopathologic entity characterized by heavy proteinuria, absence of edema and an irreversible decline in renal function. Findings on renal biopsy include: collapsed glomerular capillaries; visceral glomerular epitheliosis; microcystic tubules; mesangial prominence; and endothelial tubuloreticular inclusions. Early in the AIDS epidemic, HIVAN was the predominant glomerular lesion observed in HIV-infected patients. It is being increasingly recognized, especially in Caucasian populations, that a variety of immune complex-mediated lesions such as membranoproliferative glomerulonephritis, proliferative glomerulonephritis and IgA nephropathy are associated with HIV infection. In this review we present two cases: one patient whose first presentation of AIDS was end-stage renal disease, who on biopsy was found to have HIVAN, and the second, who was infected with HIV, and on biopsy was found to have hepatitis C-related hepatitis C related membranoproliferative glomerulonephritis. We also review the current literature on HIVAN and HIV-associated immune complex diseases (HIVICDs). Each case illustrates an important clinical point. The first that renal disease can be the first manifestation of HIV infection and the second that HIV-infected patients may develop immune complex related renal diseases, some of which may be potentially treatable.
Chronic kidney disease (CKD) is an important cause of morbidity and mortality in HIV-positive individuals. Hepatitis C (HCV) co-infection has been associated with increased risk of CKD, but prior studies lack information on potential mechanisms. We evaluated the association between HCV or hepatitis B (HBV) co-infection and progressive CKD among 3,441 antiretroviral-treated clinical trial participants. Progressive CKD was defined as the composite of end-stage renal disease, renal death, or significant glomerular filtration rate (eGFR) decline (25% decline to eGFR <60 mL/min/1.73 m2 or 25% decline with a baseline <60). Generalized Estimating Equations were used to model the odds of progressive CKD. At baseline, 13.8% and 3.3% of participants were co-infected with HCV and HBV, respectively. Median eGFR was 111, and 3.7% developed progressive CKD. After adjustment, the odds of progressive CKD were increased in participants with HCV (OR 1.72, 95% CI 1.07–2.76) or HBV (OR 2.26, 95% CI 1.15–4.44). Participants with undetectable or low HCV-RNA had similar odds of progressive CKD as HCV seronegative participants, while participants with HCV-RNA >800,000 IU/ml had increased odds (OR 3.07; 95% CI 1.60–5.90). Interleukin-6, hyaluronic acid, and the FIB-4 hepatic fibrosis index were higher among participants who developed progressive CKD, but were no longer associated with progressive CKD after adjustment. Future studies should validate the relationship between HCV viremia and CKD.
ClinicalTrials.gov NCT00027352; NCT00004978
The classic kidney disease of Human Immunodeficiency Virus (HIV) infection, HIV-associated nephropathy, is characterized by progressive acute renal failure, often accompanied by proteinuria and ultrasound findings of enlarged, echogenic kidneys. Definitive diagnosis requires kidney biopsy, which demonstrates collapsing focal segmental glomerulosclerosis with associated microcystic tubular dilatation and interstitial inflammation. Podocyte proliferation is a hallmark of HIV-associated nephropathy, although this classic pathology is observed less frequently in antiretroviral-treated patients. The pathogenesis of HIV-associated nephropathy involves direct HIV infection of renal epithelial cells, and the widespread introduction of combination antiretroviral therapy has had a significant impact on the natural history and epidemiology of this unique disease. These observations have established antiretroviral therapy as the cornerstone of treatment for HIV-associated nephropathy, in the absence of prospective clinical trials. Adjunctive therapy for HIV-associated nephropathy includes ACE inhibitors or angiotensin receptor blockers, as well as corticosteroids in selected patients with significant interstitial inflammation or rapid progression.
HIV-associated nephropathy; focal segmental glomerulosclerosis; HIV; kidney
Objectives: To describe current knowledge on the aetiology, pathology, diagnosis, and treatment of HIV associated nephropathy.
Methods: A Medline search was performed using the key words "HIV," "nephropathy," "renal," and "kidney." A further search was performed for each of the currently licensed antiretroviral agents linked to key words "renal" or "kidney" and also using the MeSH heading "pharmacokinetics."
Results: HIV associated nephropathy is a common complication of HIV in black African and Afro-Caribbean patients and presents with progressive renal failure and heavy proteinuria. As other causes of renal failure are likely to fall in incidence among patients successfully treated with highly active antiretroviral therapy (HAART), HIV associated nephropathy will become increasingly prominent as a cause of renal impairment in HIV infected patients. Recent evidence suggests that HIV associated nephropathy will respond to HAART with a dramatic improvement in renal function.
Conclusion: HIV associated nephropathy is a treatable condition. This condition should be actively sought in HIV infected patients if they are to receive the benefits of therapy.
Key Words: HIV; nephropathy; HAART
With the widespread use of combination antiretroviral agents, the incidence of HIV-associated nephropathy has decreased. Currently, HIV-infected patients live much longer and often suffer from comorbidities such as diabetes mellitus. Recent epidemiological studies suggest that concurrent HIV infection and diabetes mellitus may have a synergistic effect on the incidence of chronic kidney disease. To address this, we determined whether HIV-1 transgene expression accelerates diabetic kidney injury using a diabetic HIV-1 transgenic (Tg26) murine model. Diabetes was initially induced with low-dose streptozotocin in both Tg26 and wild-type mice on a C57BL/6 background, which is resistant to classic HIV-associated nephropathy. Although diabetic nephropathy is minimally observed on the C57BL/6 background, diabetic Tg26 mice exhibited a significant increase in glomerular injury compared with nondiabetic Tg26 mice and diabetic wild-type mice. Validation of microarray gene expression analysis from isolated glomeruli showed a significant upregulation of proinflammatory pathways in diabetic Tg26 mice. Thus, our study found that expression of HIV-1 genes aggravates diabetic kidney disease.
diabetic nephropathy; glomerulopathy; HIV
With the widespread use of combination antiretroviral agents, the incidence of HIV-associated nephropathy has decreased. Currently, HIV-infected patients live much longer and often suffer from comorbidities such as diabetes mellitus. Recent epidemiological studies suggest that concurrent HIV infection and diabetes mellitus may have a synergistic effect on the incidence of chronic kidney disease. To address this, we determined whether HIV-1 transgene expression accelerates diabetic kidney injury using a diabetic HIV-1 transgenic (Tg26) murine model. Diabetes was initially induced with low-dose streptozotocin in both Tg26 and the wild-type mice on the C57BL/6 background, which is resistant to classic HIV-associated nephropathy. Although diabetic nephropathy is minimally observed on C57BL/6 background, diabetic Tg26 mice exhibited a significant increase in glomerular injury compared to non-diabetic Tg26 mice or diabetic wild type mice. Validation of microarray gene expression analysis from isolated glomeruli showed a significant up-regulation of pro-inflammatory pathways in the diabetic Tg26 mice. Thus, our study found that expression of HIV-1 genes aggravates diabetic kidney disease
To examine the role of antiretroviral drugs (ART), HIV-related and traditional risk factors on the incidence of chronic kidney disease (CKD) in HIV-infected patients.
Prospective hospital-based cohort of HIV-infected patients from 2004 to 2012.
CKD was defined using MDRD equation as an estimated glomerular filtration rate (eGFR) less than 60 ml/mn/1.73 m2 at 2 consecutive measurements ≥3 months apart. Poisson regression models were used to study determinants of CKD either measured at baseline or updated. ART exposure was classified as ever or never. We additionally tested the role of tenofovir (TDF), whether or not prescribed concomitantly with a Protease Inhibitor (PI), taking into account the cumulative exposure to the drug.
4,350 patients (74% men) with baseline eGFR>60 ml/mn/1.73 m2 were followed for a median of 5.8 years. At the end of follow-up, 96% had received ART, one third of them (35%) jointly received TDF and a PI. Average incidence rate of CKD was 0.95% person-years of follow-up. Incidence of CKD was higher among women (IRR = 2.2), older patients (>60 y vs <45 y: IRR = 2.5 and 45–60 y: IRR = 1.7), those with diabetes (IRR = 1.9), high blood pressure (IRR = 1.5), hyperlipidemia (IRR = 1.5), AIDS stage (IRR = 1.4), low baseline eGFR (IRR = 15.8 for 6090 and IRR = 7.1 for 70500/mm3 (IRR = 2.5), and exposure to TDF (IRR = 2.0). Exposure to TDF was even strongly associated with CKD when co-administered with PIs (IRR = 3.1 vs 1.3 when not, p<0,001). A higher risk of CKD was found when tenofovir exposure was >12 months [IRR = 3.0 with joint PIs vs 1.3 without (p<0.001)]. A vast majority of those developing CKD (76.6%) had a baseline eGFR between 60 and 80 ml/mn/1.73 m2.
In patients with eGFR between 60 and 80 mL/min/1.73 m2, a thorough control of CKD risk factors is warranted. The use of TDF, especially when co-administered with PIs, should be mentioned as a relative contraindication in presence of at least one of these risk factors.
Despite widespread highly active antiretroviral therapy use, HIV disease remains associated with increased risk of kidney disease. Whether tenofovir use is associated with higher risk of kidney disease is controversial.
We evaluated the association of cumulative and ever exposure to tenofovir on kidney outcomes in 10,841 HIV-infected patients from the Veterans Health Administration who initiated antiretroviral therapy from 1997-2007.
Cox proportional hazards and marginal structural models evaluated associations between tenofovir and time to first occurrence of 1) proteinuria (two consecutive urine dipstick measurements ≥30mg/dL), 2) rapid decline in kidney function (≥3ml/min/1.73m2 annual decline), and 3) CKD (estimated glomerular filtration rate <60ml/min/1.73m2).
Median follow-up ranged from 3.9 years (proteinuria) to 5.5 years (CKD), during which 3400 proteinuria, 3078 rapid decline, and 533 CKD events occurred. After multivariable adjustment, each year of exposure to tenofovir was associated with 34% increased risk of proteinuria (95%CI 25-45%, p<0.0001), 11% increased risk of rapid decline (3-18%, p=0.0033), and 33% increased risk of CKD (18-51%; p<0.0001). Pre-existing renal risk factors did not appear to worsen the effects of tenofovir. Other ARVs showed weaker or inconsistent associations with kidney disease events. Among those who discontinued tenofovir use, risk of kidney disease events did not appear to decrease during follow-up.
Tenofovir exposure was independently associated with increased risk for three types of kidney disease events, and did not appear to be reversible. Because subtle kidney function decline affects long-term morbidity and mortality, the balance between efficacy and probable adverse effects requires further study.
HIV; antiretroviral therapy; kidney disease; tenofovir
To determine the prevalence and associated factors with chronic kidney disease (CKD) in a cohort of HIV-positive individuals with undetectable viral load on HAART.
From March, 2009 to September 2009, 213 individuals between 18-70 years, period on HAART ≥12 months, viral load < 50 copies/mm3, and CD4 ≥ 200 cells/mm3, were consecutively enrolled at the outpatient clinic of Hospital de Clínicas, Porto Alegre, Brazil. Exclusion criteria were obesity, malnourishment, amputee, paraplegic, previous history of renal disease, pregnancy and hepatic insufficiency. Renal function was determined by estimated glomerular filtration rate (eGFR) assessed by the modification of diet in renal disease. CKD was defined as an eGFR less or equal than 60 ml/min/1.73 m2, for a period of at least 3 months. Poisson regression was used to determine factors associated with CKD.
CKD was diagnosed in 8.4% of the population, and after adjustment, the risk factors were hypertension (RR = 3.88, 95%CI, 1.84 - 8.16), time on HAART (RR = 1.15, 95%CI,1.03–1.27) and tenofovir exposure (RR = 2.25, 95%CI, 1.04–4.95). Higher weight (RR = ,0.88 95%CI, 0.82–0.96) was associated to normal function.
CKD was a common finding in this cohort of patients and was related to hypertension, time on HAART and tenofovir exposure. We suggest a more frequent monitoring of renal function, especially for those with risk factors to early identify renal impairment.
Background. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is expressed by kidney tubules that are acutely damaged, but few studies have investigated the association of neutrophil gelatinase-associated lipocalin (NGAL) with different forms of chronic kidney disease (CKD). HIV-associated nephropathy (HIVAN) is a progressive form of CKD characterized by collapsing focal segmental glomerulosclerosis and microcytic tubular dilatation that typically leads to end-stage renal disease (ESRD).
Methods. Previously, we reported that microcystic tubular dilatations specifically expressed NGAL RNA, implying that the detection of uNGAL protein could mark advanced HIVAN. To test this idea, we performed a comparative study of diverse proteinuric glomerulopathies in 25 patients who were HIV positive.
Results. Eighteen patients had HIVAN and seven had other glomerulopathies (four membranoproliferative glomerulonephritis, one membranous glomerulonephritis, one amyloid and one malarial GN). HIVAN and non-HIVAN patients did not differ with respect to age, ethnicity, serum creatinine, estimated GFR, proteinuria or the prevalence of hypocomplementemia (6 versus 29%, P = 0.18), but HIVAN patients were less likely to have HCV infections. HIVAN patients expressed 4-fold higher levels of uNGAL than the patients with other glomerulopathies [387 ± 338 versus 94 ± 101 μg/g urine creatinine (uCr), P = 0.02]. A cutpoint of 121.5 μg uNGAL/g uCr demonstrated 94% sensitivity and 71% specificity for the diagnosis of HIVAN, with an area under the receiver operator characteristic curve of 0.88.
Conclusion. In summary, while HIVAN disease is currently diagnosed only by kidney biopsy, uNGAL can distinguish HIVAN from other proteinuric glomerulopathies in the HIV-infected patient, likely because of its specific expression from characteristic microcysts.
biomarker; HIV-associated nephropathy; progressive chronic kidney disease; tubular injury; urinary neutrophil gelatinase-associated lipocalin
Background. Human immunodeficiency virus associated nephropathy (HIVAN) is a rapidly progressive chronic renal parenchymal disease that occurs in HIV-infected individuals and manifests commonly as proteinuria, which is preceded by microalbuminuria (MA). This clinical entity is defined as a spot urine albumin of 20–200 mg/L. Objectives. To determine the prevalence of microalbuminuria in HIV positive children in UNTH, Enugu and compare it with that of HIV-negative children. Methods. A total of 154 HIV positive children aged 18 months to 14 years and 154 HIV-negative children of corresponding attributes were screened for microalbuminuria, using Micral test II strip which has a sensitivity of 90–99%. Results. No child among the groups (HIV positive and negative) had microalbuminuria. Majority (96.0%) of HIV-positive children had nonadvanced HIV disease at the time of the study (P = 0.00). About 77.3% were using HAART (P < 0.0001), the mean CD4 cell count of the subjects was 709.2 ± 443.9 cells/mm3; while 78.0% had nonsevere immunosuppression (P = 0.00). Furthermore, HIV-positive children with severe immunosuppression were younger and had shorter duration of treatment. Conclusion. Microalbuminuria may not be very common in Nigerian children irrespective of their HIV status.
Approximately 15% of HIV-infected individuals have comorbid diabetes. Studies suggest that HIV and diabetes have an additive effect on chronic kidney (CKD) progression; however, this observation may be confounded by differences in traditional CKD risk factors.
We studied a national cohort of HIV-infected and matched HIV-uninfected individuals who received care through the Veterans Healthcare Administration. Subjects were divided into four groups based on baseline HIV and diabetes status, and the rate of progression to an estimated glomerular filtration rate (eGFR) < 45ml/min/1.73m2 was compared using Cox-proportional hazards modeling to adjust for CKD risk factors.
31,072 veterans with baseline eGFR ≥ 45ml/min/1.73m2 (10,626 with HIV only, 5,088 with diabetes only, and 1,796 with both) were followed for a median of 5 years. Mean baseline eGFR was 94ml/min/1.73m2, and 7% progressed to an eGFR < 45ml/min/1.73m2. Compared to those without HIV or diabetes, the relative rate of progression was increased in individuals with diabetes only [adjusted hazard ratio (HR) 2.48; 95% confidence interval (CI) 2.19–2.80], HIV only [HR 2.80, 95% CI 2.50–3.15], and both HIV and diabetes [HR 4.47, 95% CI 3.87–5.17].
Compared to patients with only HIV or diabetes, patients with both diagnoses are at significantly increased risk of progressive CKD even after adjusting for traditional CKD risk factors. Future studies should evaluate the relative contribution of complex comorbidities and accompanying polypharmacy to the risk of CKD in HIV-infected individuals, and prospectively investigate the use of cART, glycemic control, and adjunctive therapy to delay CKD progression.
non-AIDS complications; HIV; chronic kidney disease; diabetes; risk factors