Long-term impact of immediate versus deferred antiretroviral therapy on kidney health in people with HIV.

People with human immunodeficiency virus (HIV) are at risk for chronic kidney disease (CKD) due to HIV and antiretroviral therapy (ART) nephrotoxicity. Immediate ART initiation reduces mortality and is now the standard of care, but the long-term impact of prolonged ART exposure on CKD is unknown. To evaluate this, the Strategic Timing of Antiretroviral Treatment (START) trial randomized 4,684 ART-naïve adults with CD4 cell count under 500 cells/mm3 to immediate versus deferred ART. We previously reported a small but statistically significantly greater decline in estimated glomerular filtration rate (eGFR) over a median of 2.1 years in participants randomized to deferred versus immediate ART. Here, we compare the incidence of CKD events and changes in eGFR and urine albumin/creatinine ratio (UACR) in participants randomized to immediate versus deferred ART during extended follow-up. Over a median of 9.3 years, eight participants experienced kidney failure or kidney-related death, three in the immediate and five in the deferred ART arms, respectively. Over a median of five years of more comprehensive follow-up, the annual rate of eGFR decline was 1.19 mL/min/1.73m2/year, with no significant difference between treatment arms (difference deferred - immediate arm 0.055; 95% confidence interval -0.106, 0.217 mL/min/1.73m2). Results were similar in models adjusted for baseline covariates associated with CKD, including UACR and APOL1 genotype. Similarly, there was no significant difference between treatment arms in incidence of confirmed UACR 30 mg/g or more (odds ratio 1.13; 95% confidence interval 0.85, 1.51). Thus, our findings provide the most definitive evidence to date in support of the long-term safety of early ART with respect to kidney health.

Association of HIV and viral suppression status with hospital acute kidney injury in the era of antiretroviral therapy.

In the modern era, it is unknown if people that are virally suppressed with HIV (PWH) are at increased risk for acute kidney injury (AKI) compared to people without HIV and no studies have compared the risk of AKI by viral suppression status. Here, we determined the associations of HIV status and AKI among PWH with and without viral suppression compared to people without HIV. An observational cohort study of PWH and people without HIV hospitalized in a large New York City health system between 2010-2019 was conducted. Multivariable Cox proportional hazards models were used to determine associations between HIV status and risk of AKI, severe AKI and development of chronic kidney disease (CKD). Among 173,884 hospitalized patients, 4,718 had HIV; 2,532 (53.7%) were virally suppressed and 2,186 (46.3%) were not suppressed. Compared to people without HIV, PWH with and without viral suppression were at increased risk of AKI (adjusted hazard ratio 1.27, 95% confidence interval 1.15, 1.40 and 1.73, 1.58, 1.90, respectively) and AKI requiring kidney replacement therapy (1.89, 1.27, 2.84 and 1.87, 1.23, 2.84, respectively). Incremental, graded associations were observed between HIV status and Stage 2 or 3 AKI, and among AKI survivors, and incident CKD. The elevated risk of AKI across ages of PWH was similar in magnitude to older people without HIV. Thus, regardless of virologic control, HIV is an independent risk factor for AKI among hospitalized patients. Future studies should determine the mechanisms by which HIV increases susceptibility to AKI and identify strategies to prevent AKI in PWH.

The association of lupus nephritis with adverse pregnancy outcomes among women with lupus in North America.

OBJECTIVES: We evaluated the association of lupus nephritis (LN) and adverse pregnancy outcomes in prospective cohorts of pregnant women with SLE (systemic lupus erythematosus). METHODS: We conducted a patient-level pooled analysis of data from three cohorts of pregnant women with SLE. Pooled logistic regression models were used to evaluate the association of LN and adverse pregnancy outcomes. Odds ratios and 95% confidence intervals were calculated using a fixed effect model by enrolling cohort. RESULTS: The pooled cohort included 393 women who received care at clinics in the United States and Canada from 1995 to 2015. There were 144 (37%) women with a history of LN. Compared to women without LN, those with LN had higher odds of fetal loss (OR: 1.90; 95% CI: 1.01, 3.56) and preeclampsia (OR: 2.04; 95% CI: 1.01, 4.13). Among the 31 women with active nephritis (defined as urine protein ≥ 0.5 g/24 h) there was a higher odds of poor pregnancy outcome (OR: 3.08; 95% CI: 1.31, 7.23) and fetal loss (OR: 6.29; 95% CI: 2.52, 15.70) compared to women without LN. CONCLUSIONS: In this pooled cohort of women with SLE, a history of LN was associated with fetal loss and preeclampsia. Active nephritis was associated with poor pregnancy outcome and fetal loss.

Etiology of Persistent Microalbuminuria in Nigeria (P_MICRO study): protocol and study design.

BACKGROUND: Microalbuminuria is an independent risk factor for cardiovascular and kidney disease and a predictor of end organ damage, both in the general population and in persons with HIV (PWH). Microalbuminuria is also an important risk factor for mortality in PWH treated with antiretroviral therapy (ART). In the ongoing Renal Risk Reduction (R3) study in Nigeria, we identified a high prevalence of microalbuminuria confirmed by two measurements 4-8 weeks apart in ART-experienced, virologically suppressed PWH. Although Stage 1 or 2 hypertension and exposure to potentially nephrotoxic antiretroviral medications were common in R3 participants, other traditional risk factors for albuminuria and kidney disease, including diabetes, APOL1 high-risk genotype, and smoking were rare. Co-infection with endemic pathogens may also be significant contributors to albuminuria, but co-infections were not evaluated in the R3 study population. METHODS: In Aim 1, we will cross-sectionally compare the prevalence of albuminuria and established kidney disease risk factors in a cohort of PWH to age- and sex-matched HIV-negative adults presenting for routine care at the Aminu Kano Teaching Hospital in Kano, Nigeria. We will leverage stored specimens from 2500 R3 participants and enroll an additional 500 PLWH recently initiated on ART (≤ 24 months) and 750 age- and sex-matched HIV-negative adults to determine the contribution of HIV, hypertension, and other comorbid medical conditions to prevalent albuminuria. In Aim 2, we will follow a cohort of 1000 HIV-positive, ART-treated and 500 HIV-negative normoalbuminuric adults for 30 months to evaluate the incidence and predictors of albuminuria. DISCUSSION: The findings from this study will support the development of interventions to prevent or address microalbuminuria in PWH to reduce kidney and cardiovascular morbidity and mortality. Such interventions might include more intensive monitoring and treatment of traditional risk factors, the provision of renin-angiotensin aldosterone system or sodium-glucose cotransporter-2 inhibitors, consideration of changes in ART regimen, and screening and treatment for relevant co-infections.

HIV at 40: kidney disease in HIV treatment, prevention, and cure.

Four decades after the first cases of HIV were reported, kidney disease remains an important comorbidity in people with HIV (PWH). Both HIV-associated nephropathy and immune complex kidney disease were recognized as complications of HIV infection in the early years before treatment was available. Although the introduction of effective antiretroviral therapy in the late 1990s resulted in dramatic improvements in survival and health in PWH, several commonly used antiretroviral agents have been associated with kidney injury. HIV infection and treatment may also promote the progression of comorbid chronic kidney disease due to traditional risk factors such as diabetes, and HIV is one of the strongest "second hits" for the high-risk APOL1 genotype. Unique considerations in the management of chronic kidney disease in PWH are largely related to the need for lifelong antiretroviral therapy, with potential for toxicity, drug-drug interactions, and polypharmacy. PWH who develop progressive chronic kidney disease are candidates for all modalities of kidney replacement therapy, including kidney transplantation, and at some centers, PWH may be candidates to serve as donors for recipients with HIV. Transplantation of kidney allografts from donors with HIV also offers a unique opportunity to study viral dynamics in the kidney, with implications for kidney health and for research toward HIV cure. In addition, HIV-transgenic animal models have provided important insights into kidney disease pathogenesis beyond HIV, and experience with HIV and HIV-related kidney disease has provided important lessons for future pandemics.

Staphylococcus aureus Bacteremia Among Patients Receiving Maintenance Hemodialysis: Trends in Clinical Characteristics and Outcomes.

RATIONALE & OBJECTIVE: Staphylococcus aureus (Saureus) bacteremia (SAB) is associated with morbidity and mortality in patients receiving maintenance hemodialysis (HD). We evaluated changes in clinical and bacterial characteristics, and their associations with clinical outcomes with SAB in this population over a 21-year period. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 453 hospitalized, non-neutropenic adults receiving maintenance HD who developed monomicrobial SAB between 1995 and 2015. EXPOSURE: Clinical characteristics and bacterial genotype. OUTCOME: All-cause and SAB-attributable mortality, persistent bacteremia, and metastatic complications. ANALYTICAL APPROACH: Proportions of participants experiencing each outcome were calculated overall and by calendar year. Secular trends were estimated using binomial risk regression, a generalized linear model with the log link function for a binomial outcome. Associations with outcomes were estimated using logistic regression. RESULTS: Over the 21-year study period, patients receiving maintenance HD experienced significant increases in age- and diabetes-adjusted SAB-attributable mortality (0.45% [95% CI, 0.36%-0.46%] per year), persistent bacteremia (0.86% [95% CI, 0.14%-1.55%] per year), metastatic complications (0.84% [95% CI, 0.11%-1.56%] per year), and infection with the virulent Saureus clone USA300 (1.47% [95% CI, 0.33%-2.52%] per year). Over time, the suspected source of SAB was less likely to be a central venous catheter (-1.32% [95% CI, -2.05 to-0.56%] per year) or arteriovenous graft (-1.08% [95% CI, -1.54 to-0.56] per year), and more likely to be a nonvascular access source (1.89% [95% CI, 1.29%-2.43%] per year). Patients with a nonvascular access suspected source of infection were more likely to die as a result of their S aureus infection (OR, 3.20 [95% CI, 1.36-7.55]). The increase in USA300 infections may have contributed to the observed increase in persistent bacteremia (OR, 2.96 [95% CI, 1.12-7.83]) but did not explain the observed increases in SAB-attributable mortality (OR, 0.83 [95% CI, 0.19-3.61]) or metastatic complications (OR, 1.34 [95% CI, 0.53-3.41]). LIMITATIONS: Single-center, inpatient cohort. CONCLUSIONS: The clinical and molecular epidemiology of SAB in patients receiving maintenance HD has changed over time, with an increase in SAB-attributable mortality and morbidity despite a decline in catheter-related infections.

Randomized Placebo-Controlled Trial of Reloxaliase in Enteric Hyperoxaluria.

BACKGROUND: Enteric hyperoxaluria is caused by increased intestinal oxalate absorption and can lead to kidney stones, chronic kidney disease, and kidney failure. Reloxaliase is an orally administered recombinant enzyme that degrades oxalate along the gastrointestinal tract, thereby preventing its absorption. METHODS: We randomly assigned participants with enteric hyperoxaluria to reloxaliase or placebo, three to five times per day with food for 4 weeks. The primary end point was percent change from baseline in 24-hour urinary oxalate (UOx) excretion during weeks 1 to 4. Secondary end points included the proportion of participants with more than a 20% reduction in 24-hour UOx and an efficacy assessment in the bariatric surgery subgroup. RESULTS: A total of 115 patients underwent randomization. The 24-hour UOx decreased from a baseline geometric mean of 83.2 to 67.4 mg/24 hr during weeks 1 to 4 in reloxaliase-treated participants. Corresponding data for placebo-treated participants were 84.2 to 78.1 mg/24 hr. Estimates from the mixed-effect model repeated-measures (MMRM) analysis showed a 22.6% reduction in geometric mean UOx during weeks 1 to 4 for reloxaliase and 9.7% for placebo, a difference of 14.3 percentage points (95% confidence interval [CI], 4.9 to 22.8; P=0.004). A 20% or greater reduction in 24-hour UOx was observed in 48.3% of reloxaliase-treated participants and 31.6% of placebo-treated participants (P=0.06). In the bariatric surgery subgroup, MMRM analysis showed a 21.2% reduction in geometric mean UOx for reloxaliase and a 6.0% reduction for placebo, for a difference of 16.2 percentage points (95% CI, 4.2% to 26.7%). Adverse events occurred in 69% of reloxaliase-treated participants versus 53% of individuals taking placebo and were most commonly gastrointestinal. All but one of the adverse events were grade 1 or 2 in severity; no reloxaliase-treated participants discontinued the study. CONCLUSIONS: Reloxaliase treatment for 4 weeks reduced UOx excretion in patients with enteric hyperoxaluria; adverse events were relatively common, but not dose-limiting. These data establish the foundation for a clinical trial to determine the impact of reloxaliase on nephrolithiasis in patients with enteric hyperoxaluria. (Funded by Allena Pharmaceuticals; ClinicalTrials.gov number, NCT03456830.)

Mechanisms of Proteinuria in HIV.

Proteinuria is common in the setting of HIV infection, and may reflect comorbid kidney disease, treatment-related nephrotoxicity, and HIV-related glomerular diseases. The mechanisms of podocyte and tubulointerstial injury in HIV-associated nephropathy (HIVAN) have been the subject of intense investigation over the past four decades. The pathologic contributions of viral gene expression, dysregulated innate immune signaling, and ancestry-driven genetic risk modifiers have been explored in sophisticated cellular and whole animal models of disease. These studies provide evidence that injury-induced podocyte dedifferentiation, hyperplasia, cytoskeletal dysregulation, and apoptosis may cause the loss of glomerular filtration barrier integrity and slit diaphragm performance that facilitates proteinuria and tuft collapse in HIVAN. Although the incidence of HIVAN has declined with the introduction of antiretroviral therapy, the collapsing FSGS lesion has been observed in the context of other viral infections and chronic autoimmune disorders, and with the use of interferon-based therapies in genetically susceptible populations. This highlights the fact that the lesion is not specific to HIVAN and that the role of the immune system in aggravating podocyte injury warrants further exploration. This review will summarize our progress in characterizing the molecular mechanisms of podocyte dysfunction in HIVAN and other forms of HIV-associated kidney disease.

Regional and Racial Disparities in HIV-Related Kidney Disease.

Clinical Background and Epidemiology: Worldwide, an estimated 38 million people are living with HIV infection. The classic kidney disease of HIV infection, commonly known as HIV-associated nephropathy, is a collapsing form of focal segmental glomerulosclerosis that almost exclusively affects individuals of African descent with advanced HIV disease. People living with HIV are also at risk for immune-complex kidney diseases, antiretroviral nephrotoxicity, and kidney disease due to co-infections and comorbidities. Challenges: The burden of HIV-related kidney disease is greatest in traditionally disadvantaged populations in resource-limited settings in sub-Saharan Africa and the Caribbean and among minority populations in the United States and Europe. Factors contributing to these disparities include a higher prevalence of HIV infection, limited access to optimal antiretroviral therapy, and genetic susceptibility to kidney disease. Treatment and Prevention: Current treatment guidelines recommend the initiation of life-long antiretroviral therapy in all people living with HIV to prevent AIDS and non-AIDS complications, including kidney disease. People living with HIV who progress to end-stage kidney disease despite treatment are candidates for dialysis and kidney transplant, including the possibility of accepting organs from HIV-positive donors in some settings. Although HIV prevention is currently the only definitive solution, expanding access to antiretroviral therapy, dialysis, and kidney transplantation in people living with HIV are important intermediate steps to address the global burden of HIV-related kidney disease.

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.

To dose-adjust or not to dose-adjust: lamivudine dose in kidney impairment.

OBJECTIVES: To assess the risk of adverse diagnoses and laboratory abnormalities associated with a 300 or 150 mg daily dose of lamivudine (3TC) initiated by people with HIV (PWH) with an estimated glomerular filtration rate (eGFR) between at least 30 and 49 ml/min per 1.73 m2 or less. DESIGN: Longitudinal study based on electronic health records of 539 PWH with eGFR between at least 30 and 49 ml/min per 1.73 m2 or less from the Observational Pharmaco-Epidemiology Research and Analysis (OPERA) cohort. METHODS: Common unintended effects of 3TC were evaluated as composite outcomes. We estimated the incidence (univariate Poisson regression) and association between dose and incident composite outcomes (multivariate Poisson regression) among PWH without the relevant diagnoses or laboratory abnormalities at 3TC initiation. RESULTS: PWH initiating 150 mg 3TC had higher HIV RNA, lower eGFR, and more comorbidities than those initiating 300 mg 3TC. The prevalence of relevant diagnoses and laboratory abnormalities was similar in both groups. The most common lab abnormality was low hemoglobin. There was no statistically significant difference in incident adverse diagnoses/severe lab abnormalities with 300 mg versus 150 mg [incidence rate ratio (IRR): 1.51; 95% confidence interval (CI) 0.59--3.92). However, a statistically significant association was observed when gastrointestinal symptoms/moderate lab abnormalities were included in the outcome (IRR: 3.07, 95% CI 1.12--8.40). CONCLUSION: As 3TC is a well tolerated drug with a wide therapeutic window, dose adjustment may be unnecessary among PWH with eGFR between at least 30 and 49 ml/min per 1.73 m2 or less. Clinical judgement is key when weighing the risks and benefits of 3TC dose adjustment for PWH experiencing gastrointestinal symptoms or moderate lab abnormalities.

Kidney injury biomarkers during exposure to tenofovir-based preexposure prophylaxis.

We previously reported a higher incidence of non-albumin proteinuria and a small but significant decline in estimated glomerular filtration rate (eGFR) among HIV-negative adults randomized to emtricitabine/tenofovir disoproxil fumarate preexposure prophylaxis (FTC/TDF PrEP) versus placebo. In a nested case--control study among participants randomized to FTC/TDF PrEP, established kidney injury biomarkers measured at 12 months were not significantly different between participants who subsequently experienced one of these kidney endpoints and randomly selected controls who did not.

An Evaluation of Baseline Kidney Function in the REPRIEVE Trial of Pitavastatin in Human Immunodeficiency Virus.

BACKGROUND: Chronic kidney disease is a common comorbid condition among persons living with human immunodeficiency virus (PWH). We characterized baseline kidney function in the REPRIEVE (Randomized Trial to Prevent Vascular Events in HIV) trial cohort. METHODS: REPRIEVE enrolled PWH with low to moderate cardiovascular risk based on traditional risk factors to evaluate the effect of statin therapy on cardiovascular events. We determined baseline estimated glomerular filtration rate (eGFR) with the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Modification of Diet in Renal Disease, and Cockcroft-Gault equations, and we evaluated baseline factors associated with eGFR <90 mL/min/1.73 m2 by logistic regression. We performed Bland-Altman plots and scatterplots to assess agreement between equations. RESULTS: Among 7770 participants enrolled, the median age was 50 years, 31% were female (natal sex), 43% black or African American and 15% Asian, the median body mass index (calculated as calculated as weight in kilograms divided by height in meters squared) was 25.8, and the median CD4 cell count 620/µL. The median CKD-EPI eGFR was 97 mL/min/1.73 m2, and 38% had an eGFR <90 mL/min/1.73 m2. In the adjusted model, factors associated with eGFR <90 mL/min/1.73 m2 included white race, older age, higher body mass index, high-income region of enrollment, hypertension, and tenofovir disoproxil fumarate. The CKD-EPI and Modification of Diet in Renal Disease equations demonstrated strong agreement, particularly at lower eGFR values. Overall, there was 56% concordance between the 3 equations (categories <60, 60 to <90, ≥90 mL/min), improving to 73% after accounting for individual body surface area. CONCLUSIONS: REPRIEVE enrolled a diverse cohort including a substantial number of PWH with reduced kidney function. Factors associated with reduced eGFR included traditional risk factors and tenofovir disoproxil fumarate exposure. Three commonly used equations have only fair agreement, with potential implications for both clinical care and epidemiologic studies. CLINICAL TRIALS REGISTRATION: NCT02344290.

The spectrum of kidney biopsy findings in HIV-infected patients in the modern era.

HIV-associated kidney disease is evolving rapidly. Few North American studies have addressed modern trends and none has applied the 2018 Kidney Disease Improving Global Outcomes (KDIGO) pathologic classification. Therefore we performed a retrospective clinical-pathologic analysis of all HIV-positive patients with kidney biopsy interpreted at Columbia University from 2010-2018 using the KDIGO classification. The biopsy cohort of 437 HIV-positive patients had median age 53 years, including 66% males, 80% on anti-retroviral therapy, 57% with hypertension, 31% with diabetes, 27% with hepatitis C and 6% with hepatitis B co-infections. Race, known in 308 patients, included 58% black, 25% white and 17% Hispanic. Pathologic diagnoses were surprisingly diverse. Immune complex glomerulonephritis (ICGN) and diabetic nephropathy each outnumbered HIV-associated nephropathy, followed by tenofovir nephrotoxicity, FSGS- not otherwise specified (NOS) and global sclerosis (NOS). HIV-associated nephropathy was the most common disease in patients not on anti-retroviral therapy, and 94% were black. The association of FSGS (NOS) with black race (68%) and anti-retroviral therapy use (77%) suggests some cases may represent attenuated HIV-associated nephropathy. The most common ICGNs were IgA nephropathy and membranous glomerulopathy, both associating with anti-retroviral therapy (over 90%), followed by hepatitis C-associated proliferative ICGN. Among the 16 cases of uncharacterized ICGN lacking identifiable etiology, 69% were not on anti-retroviral therapy, possibly representing true HIV-associated immune complex kidney disease. Dual diseases occurred in 17% of patients, underscoring lesion complexity. Thus, anti-retroviral therapy has shifted the landscape of HIV-associated kidney disease toward diverse ICGN, diabetic nephropathy, and non-collapsing glomerulosclerosis, but has not eradicated HIV-associated nephropathy.