Prevalence of tubulopathy and association with renal function loss in HIV-infected patients

Effects of Prolonged Administration of Tenofovir Disoproxil Fumarate-Containing Antiviral Regimen on Renal Function in Low-Risk of Kidney Injury HIV Patients

This study intended to investigate the impact of long-term tenofovir fumarate (TDF) antiviral regimen on renal function in human immunodeficiency virus (HIV)-infected patients with low-risk of kidney injury. The observational study involving 100 HIV-infected patients without underlying diseases who achieved virological suppression and immunological recovery after sustained antiviral regimen of TDF+ lamivudine+ efavirenz (TLE) for 3.19 years. Renal function, including estimated glomerular filtration rate (eGFR), blood and urine β2 microglobulin, and other parameters, was assessed every 3 months over a period of 2.5 years. The eGFR showed a slight increasement from 116.0 at month 0 to 119.7 at month 30. Blood β2 microglobulin increased from 2.02 mg/L at month 0 to 2.77 mg/L at month 30. Compared to month 0, the difference in blood β2 microglobulin was statistically significant at month 6 and months 12-30 (P < .05). The incidence of proximal renal tubular dysfunction fluctuated from 2% at month 0 to 2.5% at month 30. The urine β2 microglobulin fluctuated from 0.5 (0.3-1.1) to 0.8 (0.5-1.35) mg/L at months 18-30, which was higher than 0.41 (0.18-1.1) mg/L at month 0 (P < .05). The abnormal concentration proportion of urine β2 microglobulin fluctuated from 72.7% to 81.3% at months 18-30, which was higher than the proportion of 57.0% at month 0. The abnormal proportion of blood β2 microglobulin, urine β2 microglobulin, and proximal renal tubular dysfunction were not correlated with eGFR (r1 = 0.119, r2 = -0.008, r3 = -0.165, P > .05). Long-term TDF antiviral regimen in low-risk of kidney injury HIV-infected patients may lead to damage in the proximal renal tubules and glomeruli. Blood and urine β2 microglobulin levels may be helpful in screening for renal dysfunction.

Chronic Kidney Disease and Accelerated Decline of Renal Function in Older Adults with HIV in Northern Thailand

Kidney disease remains prevalent in people living with HIV even in the antiretroviral treatment era. We determine the frequency of chronic kidney disease (CKD), rate of renal function decline, and associated factors in older adults with HIV (OAHIV) aged ≥50 years in northern Thailand. We used data from the medical records and calculated the estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration equation. Of the 269 participants (58% women, 61.8 years median age), 7.1% had CKD (eGFR <60 mL/min per 1.73 m2). There were 21 OAHIV (7.8%) with >25% decline in eGFR in the past year, 90 (33%) with accelerated (>5 mL/min per 1.73 m2 per year), and 44 (16%) with rapid (>10 mL/min per 1.73 m2 per year) declining eGFR. Female gender was the only factor associated with an accelerated decline in eGFR (odds ratio, 2.307; 95% confidence interval, 1.331-3.998; p = .003). Continuous monitoring of renal function is recommended for OAHIV to guide treatment modification and intervention.

Drug toxicity in the proximal tubule: new models, methods and mechanisms

The proximal tubule (PT) reabsorbs most of the glomerular filtrate and plays an important role in the uptake, metabolism and excretion of xenobiotics. Some therapeutic drugs are harmful to the PT, and resulting nephrotoxicity is thought to be responsible for approximately 1 in 6 of cases of children hospitalized with acute kidney injury (AKI). Clinically, PT dysfunction leads to urinary wasting of important solutes normally reabsorbed by this nephron segment, leading to systemic complications such as bone demineralization and a clinical scenario known as the renal Fanconi syndrome (RFS). While PT defects can be diagnosed using a combination of blood and urine markers, including urinary excretion of low molecular weight proteins (LMWP), standardized definitions of what constitutes clinically significant toxicity are lacking, and identifying which patients will go on to develop progressive loss of kidney function remains a major challenge. In addition, much of our understanding of cellular mechanisms of drug toxicity is still limited, partly due to the constraints of available cell and animal models. However, advances in new and more sophisticated in vitro models of the PT, along with the application of high-content analytical methods that can provide readouts more relevant to the clinical manifestations of nephrotoxicity, are beginning to extend our knowledge. Such technical progress should help in discovering new biomarkers that can better detect nephrotoxicity earlier and predict its long-term consequences, and herald a new era of more personalized medicine.

Renal adverse drug reactions

PURPOSE OF REVIEW

Chronic kidney disease (CKD) is common in people living with HIV (PLWH) and is related to a multitude of factors. The aim of this review is to provide an overview of the most recent evidence of renal adverse effects of antiretroviral drugs, predictors of CKD risk and areas for future research.

RECENT FINDINGS

Advancing age, cardiometabolic risk factors and adverse effects of antiretroviral drugs contribute to the higher prevalence of CKD in PLWH. Genetic factors and baseline clinical CKD risk are strongly correlated to risk of incident CKD, although it is unclear to what extent gene polymorphisms explain renal adverse effects related to tenofovir disoproxil fumarate (TDF). Switching from TDF to tenofovir alafenamide (TAF) in people with baseline renal dysfunction improves renal parameters; however, the long-term safety and benefit of TAF in individuals at low risk of CKD is an area of ongoing research.

SUMMARY

Several factors contribute to estimated glomerular function decline and CKD in PLWH. Clinical risk scores for CKD may be useful to inform selection of ART in an ageing population. In people with baseline renal dysfunction, potentially nephrotoxic antiretroviral drugs should be avoided.

Cystatin C and Urine Albumin to Creatinine Ratio Predict 5-Year Mortality and Cardiovascular Events in People Living With HIV

BACKGROUND

Identifying people with HIV (PWH) at risk for chronic kidney disease, cardiovascular events, and death is crucial. We evaluated biomarkers to predict all-cause mortality and cardiovascular events, and measured glomerular filtration rate (mGFR) slope.

METHODS

Biomarkers were measured at enrollment. Baseline and 5-year mGFR were measured by plasma iohexol clearance. Outcomes were a composite criterion of all-cause mortality and/or cardiovascular events, and mGFR slope.

RESULTS

Of 168 subjects, 146 (87.4%) had undetectable HIV load. Median follow-up was 59.1 months (interquartile range, 56.2-62.1). At baseline, mean age was 49.5 years (± 9.8) and mean mGFR 98.9 mL/min/1.73m2 (± 20.6). Seventeen deaths and 10 cardiovascular events occurred during 5-year follow-up. Baseline mGFR was not associated with mortality/cardiovascular events. In multivariable analysis, cystatin C (hazard ratio [HR], 5.978; 95% confidence interval [CI], 2.774-12.88; P < .0001) and urine albumin to creatinine ratio (uACR) at inclusion (HR, 1.002; 95% CI, 1.001-1.004; P < .001) were associated with mortality/cardiovascular events. Area under receiver operating curve of cystatin C was 0.67 (95% CI, .55-.79) for mortality/cardiovascular event prediction. Biomarkers were not associated with GFR slope.

CONCLUSIONS

uACR and cystatin C predict all-cause mortality and/or cardiovascular events in PWH independently of mGFR.

Microalbuminuria: a sentinel of neurocognitive impairment in HIV-infected individuals?

Background

According to population-based studies, microalbuminuria is associated with subsequent cognitive decline over a 4–6-year period, because of cerebral small-vessel disease (CSVD). This prospective cross-sectional study (NCT02852772) was designed to evaluate whether a history of microalbuminuria is associated with subsequent cognitive decline in combined antiretroviral therapy (cART)-treated persons living with human immunodeficiency virus (PLHIVs).

Methods

From our computerized medical database, we identified 30 PLHIVs (median age 52 years), immunovirologically controlled on cART, who had microalbuminuria in 2008 and had undergone, between 2013 and 2015, a comprehensive neuropsychological assessment (NPA) including seven domains (cases): information-processing speed, motor skills, executive functions, attention/working memory, learning/memory, reasoning and verbal fluency. Forty-nine PLHIVs matched for age (median age 48 years; p = 0.19), sex, and year of first HIV-seropositivity without microalbuminuria in 2008 were identified and underwent the same NPA between 2013 and 2015 (controls).

Results

Cases performed less well than controls for information-processing speed (p = 0.01) and motor skills (p = 0.02), but no differences were found for the other cognitive domains and global z-scores. A multivariable linear-regression model adjusted for confounding factors confirmed the microalbuminuria effect for the information-processing-speed z score.

Conclusion

cART-treated PLHIVs with a history of microalbuminuria subsequently had worse cognitive performances for the information-processing-speed domain, possibly because of CSVD. Our observations should be considered preliminary findings of a temporal link between microalbuminuria, CSVD, and subsequent cognitive impairment.