Predictors of HIV-associated nephropathy

Kidney function in healthcare clients in Khayelitsha, South Africa: Routine laboratory testing and results reflect distinct healthcare experiences by age for healthcare clients with and without HIV

In South Africa, PLHIV are eligible for free ART and kidney function screening. Serum creatinine (SCr) laboratory test data from the National Health Laboratory Service are collated at the Provincial Health Data Centre and linked with other routine health data. We analysed SCr and estimated glomerular filtration rate (eGFR) results for PLHIV and HIV-negative healthcare clients aged 18-80 years accessing healthcare in Khayelitsha, South Africa and comorbidity profiles at SCr and eGFR testing. 45 640 individuals aged 18-80 years with at least one renal test accessed Khayelitsha public health facilities in 2016/2017. 22 961 (50.3%) were PLHIV. Median age at first SCr and eGFR test for PLHIV was 33yrs (IQR: 27,41) to 36yrs (IQR: 30,43) compared to 49yrs (IQR: 37,57) and 52yrs (IQR: 44,59) for those without HIV. PLHIV first median SCr results were 66 (IQR: 55,78) μmol/l compared to 69 (IQR: 58,82) μmol/l for HIV-negative individuals. Hypertension, diabetes, and CKD at testing were more common in HIV-negative people than PLHIV. HIV, diabetes and tuberculosis (TB) are associated with higher eGFR results; whilst hypertension, being male and older are associated with lower eGFR results. These data reflect testing practices in the Western Cape: younger people without HIV have generally worse kidney function test results; younger PLHIV have generally good test results, and older people with/without HIV have generally similar test results, reflecting regular screening for kidney function in asymptomatic PLHIV whereas young HIV-negative people are tested only when presenting with renal symptoms. Our analysis suggests we cannot infer the future healthcare requirements of younger PLHIV based on the current ageing population, due to changing ART availability for different generations of PLHIV. Instead, routine health data may be used in an agile way to assess ongoing healthcare requirements of ageing PLHIV, and to reflect implementation of treatment guidelines.

Assessing renal impairment in treatment-naïve adolescents living with HIV commencing antiretroviral therapy in Zimbabwe

OBJECTIVE

People with HIV (PWH) are increasingly experiencing non-communicable complications, including renal impairment, which are associated with worse clinical outcomes. Limited information exists surrounding renal impairment in paediatric PWH, of which the majority live in sub-Saharan Africa, and further information is required to guide clinical practice. This study describes the prevalence of new or worsening renal impairment in adolescents commencing antiretroviral therapy (ART) in Zimbabwe and associated risk factors.

DESIGN

Retrospective cohort study.

METHODS

Data were collected between January 2010 to January 2019 from the medical records of adolescents aged 12-17 years initiating ART at an outpatient HIV clinic in Zimbabwe. Renal function (estimated glomerular filtration rate, eGFR) was calculated using the Full Age Spectrum formula. Proteinuria was defined as a single urine dipstick score of ≥1+. Potential predictors of renal impairment at follow-up were assessed by logistical regression.

RESULTS

Two hundred and sixty-six adolescents were included in analysis. Baseline renal impairment (eGFR < 90 ml/min/1.73 m 2 ) and proteinuria were present in 13% and 7% of the cohort, respectively. After a median of 4.1 years (interquartile range: 1.9-6.9) following ART commencement, mean eGFR increased by 10 ml/min/1.73 m 2 ( P  < 0.01), and the prevalence of renal impairment decreased to 8% ( P  < 0.01). Baseline renal impairment predicted renal impairment at follow-up (odds ratio [OR] 8.98; 95% confidence interval [CI] 2.81-28.68; P  < 0.01). Proteinuria trended towards association with renal impairment at follow-up (OR 4.39; 95% CI 0.95-20.31; P  = 0.06).

CONCLUSIONS

Renal impairment is common in adolescent ART-naïve PWH, and baseline renal impairment is associated with longstanding renal impairment, whereas baseline proteinuria trended towards an association with longstanding renal impairment.

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.

Performance of Creatinine- and Cystatin C-Based Equations for Glomerular Filtration Rate Estimation in HIV-1-Infected Individuals Receiving Dolutegravir + Tenofovir Disoproxil Fumarate + Lamivudine as Initial Antiretroviral Therapy: A Retrospective Observational Study

BACKGROUND

Dolutegravir (DTG) may inhibit organic cation transporter-2 in renal tubules and elevate serum creatinine levels without true renal function deterioration. There are scarce data on the glomerular filtration rate (GFR) equations in Chinese HIV patients with DTG/TDF/3 TC. This retrospective study was to evaluate the changes in creatinine- and cystatin C-based estimated GFR values among Chinese adult HIV patients with initial highly active antiretroviral therapy (HAART) with DTG/TDF/3 TC for 48 weeks.

SETTINGS

Retrospective analysis of Chinese adult HIV patients who received initial HAART with DTG/TDF/3 TC between January 2016 and May 2021.

METHODS

We compared the changes in creatinine-based and cystatin C-based estimated GFR before and 48 weeks after HAART to determine the optimal tool for renal function estimation.

RESULTS

Ninety-five patients [91.58% men; median age, 34 years (interquartile range, 29-44 years)] were enrolled. The median baseline CD4+ cell count was 185 cells/µL [interquartile range, 53-303 cells/µL] and the median baseline viral load was 148,000 copies/mL [interquartile range, 26,800-596,000 copies/mL]. The estimated GFR at 4, 12, and 24 weeks was significantly different than at baseline (P < 0.05) using all 4 equations. Only the GFR estimated using the CKD-EPIcreat and CKD-EPIcys equations was significantly different at 48 weeks of treatment (P < 0.05). The modification of diet in renal disease-based decline of GFR incidence at 4, 12, 24, and 48 weeks of treatment (21.5%, 24.21%, 33.68% and 38.95%, respectively) was higher than that calculated using the other 3 GFR equations.

CONCLUSIONS

The modification of diet in renal disease equation may not be optimal for Chinese HIV-1-infected adults receiving DTG + TDF + 3 TC as the initial antiviral therapy. Clinicians must carefully choose the GFR equation for patients with HIV/hepatitis B virus coinfection.

Kidney Transplantation in HIV-positive Patients: Current Practice and Management Strategies

BACKGROUND

HIV-positive patients had been successfully transplanted for the last 15 y and the donor pool had successfully been expanded to also include HIV-positive donors.

METHODS

We aimed to evaluate the effectiveness of transplantation in HIV-positive patients and highlight some of the important issues reported in the literature. We pooled clinical data from different cohorts to show some of the common issues encountered in HIV-positive transplantation. Furthermore, we searched MEDLINE via PubMed, EMBASE, Cochrane CENTRAL to create a comprehensive table for current evidence for different issues currently encountered when transplanting HIV-positive patients.

RESULTS

We included data from 19 cohort studies and reported on outcomes of the current HIV-positive transplant programs. We made recommendations based on personal experience as well as the experience reported in the literature regarding rejection, opportunistic infection, and HIV-associated nephropathy. Opportunistic infections and malignancies are not a major problem for this population group.

CONCLUSIONS

HIV-positive patients encounter very specific issues after transplantation, specifically related to drug interactions and higher rejection rates. When utilizing HIV-positive donors, the recurrence of HIV-associated nephropathy in the graft kidney is an issue which can be important. Despite some issues with high rejection rates, HIV-positive patients have similar results to HIV-negative patients posttransplantation.

Early HIV infection is associated with reduced proportions of gamma delta T subsets as well as high creatinine and urea levels

Renal dysfunctions are major predictors of co-morbidities and mortality in HIV-infected individuals. Unconventional T cells have been shown to regulate kidney functions. However, there is dearth of information on the effect of HIV-associated nephropathies on γδ and DN T cells. It is also not clear whether γδ T cell perturbations observed during the early stages of HIV infection occur before immune activation. In this study, we investigated the relationship between creatinine and urea on the number of unconventional T cells in HIV-infected individuals at the early and chronic stages of infection. Persons in the chronic stage of infection were divided into treatment naïve and exposed groups. Treatment exposed individuals were further subdivided into groups with undetectable and detectable HIV-1RNA in their blood. Creatinine and urea levels were significantly higher among persons in the early HIV infection compared with the other groups. Proportions of γδ T, γδ + CD8, γδ + CD16 cells were also significantly reduced in the early stage of HIV infection (P < .01). Markers of immune activation, CD4 + HLA-DR and CD8 + HLA-DR, were also significantly reduced during early HIV infection (P < .01). Taken together, our findings suggest that high levels of renal markers as well as reduced proportions of gamma delta T cells are associated with the early stages of HIV infection. This event likely occurs before systemic immune activation reaches peak levels. This study provides evidence for the need for early HIV infection diagnosis and treatment.

Factors associated with bone microstructural alterations assessed by HR-pQCT in long-term HIV-infected individuals

PURPOSE

In adults with long-term HIV infection, low bone density and increased fracture risk have emerged as significant comorbidities. Our aim was to assess the association of exercise, nutrition, and medications with bone quality in adults with long-term HIV infection.

METHODS

Forty-three adults with HIV infection were enrolled (median BMI 25.7, range 18.2-35.6 kg/m²; median age 57, range 50-69 years). Participants underwent ultradistal radius and tibia high-resolution peripheral quantitative CT (HR-pQCT). Questionnaires included the revised Community Healthy Activities Model Program for Seniors (CHAMPS), the Mini Nutritional Assessment (MNA) as well as medication assessments. Multivariable linear regression models were used to evaluate the association of exercise, nutritional status, tenofovir disoproxil fumarate (TDF) and protease inhibitor (PI) use with bone density and microstructure, adjusting for demographic risk factors.

RESULTS

In regression models, higher nutrition scores were associated with higher tibia cortical thickness (R² = 0.23; β = 0.03; p = 0.044) and higher radius cortical BMD (R² = 0.43; β = 8.4; p = 0.026). Higher weekly frequency of all physical activities was significantly associated with higher radius trabecular BMD (R² = 0.38; β = 0.96; p = 0.050), higher radius trabecular number (R² = 0.31; β = 0.01; p = 0.026), lower tibia and radius trabecular separation (tibia: R² = 0.30; β = -0.003; p = 0.038; radius: R² = 0.35; β = -0.003; p = 0.021), and higher radius bone stiffness (R² = 0.45; β = 0.38; p = 0.047). Higher frequency of bone loading physical activities was significantly associated with higher tibia trabecular density (R² = 0.44; β = 4.06; p = 0.036), higher tibia bone stiffness (R² = 0.46; β = 3.06; p = 0.050), and higher tibia estimated failure load (R² = 0.46; β = 0.17; p = 0.049). TDF used in combination with a PI was associated with lower radius trabecular BMD (R² = 0.39; β = -41.2; p = 0.042), lower radius trabecular number (R² = 0.34; β = -0.44; p = 0.009) and greater radius trabecular separation (R² = 0.42; β = 0.16; p = 0.002), while TDF use without a PI was not associated with reduced bone quality.

CONCLUSIONS

In adults with HIV infection, malnutrition is associated with poor cortical bone quality, while reduced frequency of physical activities and specifically reduced frequency of mechanical loading activities are associated with deficient trabecular bone structure and reduced estimates of bone strength. TDF use in combination with a PI is associated with deleterious effects on trabecular bone structure.

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.

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.

Diagnostic challenges of kidney diseases in HIV-infected patients

INTRODUCTION

Chronic kidney disease (CKD) is a prevalent comorbidity in persons living with HIV infection (PLWH) associated with an increase in cardiovascular morbidity and all-cause mortality. Furthermore, early diagnosis of CKD is difficult in PLWH. Areas covered: We reviewed the main diagnostic tools for CKD in PLWH, and discussed their strengths and limits. We performed a literature search on PubMed to identify reviews and clinical trials dealing with attractive kidney biomarkers of CKD in PLWH, with the following key words: 'HIV AND kidney', 'HIV AND Kidney biomarkers', 'CKD AND Kidney biomarkers'. Expert commentary: Currently, CKD diagnosis is based on the estimation of Glomerular Filtration Rate (GFR), and measurement of proteinuria by urine protein/creatinine ratio (uPCR). These parameters are independent and complementary predictors of outcomes. GFR estimates are lacking in accuracy in PLWH. The best GFR estimate is CKD-EPI study equation. Moreover, low-grade proteinuria is associated with an increased risk of kidney disease progression in PLWH, and guidelines derived from the general population may lack sensitivity. Different biomarkers of kidney diseases like N-acetyl beta glucosaminidase (NAG), Kidney Injury Molecule-1 (KIM-1), and Alpha-1-microglobulin may predict kidney disease progression and mortality in PLWH. Others may help clinicians detect antiretroviral-induced tubulopathy, or predict cardiovascular events. More studies are needed to validate the routine use of these types of biomarkers.

Application of Ultrasonography in the Diagnosis of Infectious Diseases in Resource-Limited Settings

Ultrasound (US) has vast potential in the field of infectious diseases, especially so in resource-limited settings. Recent technological advances have increased availability and access to ultrasound in low-resource settings, where the burden of infectious diseases is greatest. This paper collates the evidence for the utilization of ultrasound and evaluates its effectiveness in the diagnosis and management of a range of infectious diseases. This paper explores the role of ultrasound in population-based screening for specific diseases as well as highlights its benefits for individual patient management. We describe the common diagnostic signs seen on US for common and neglected parasitic, bacterial, and viral diseases. We proceed to document the emerging field of chest US which is proving to be a superior imaging modality for the diagnosis of specific pulmonary conditions. We conclude by discussing the efforts needed to formalize and rigorously evaluate the role of ultrasound in infectious diseases.

Solving the Blood-Brain Barrier Challenge for the Effective Treatment of HIV Replication in the Central Nervous System

Recent decades mark a great progress in the treatment of HIV infection. What was once a deadly disease is now a chronic infection. However, HIV-infected patients are prone to develop comorbidities, which severely affect their daily functions. For example, a large population of patients develop a variety of neurological and cognitive complications, called HIV associated neurological disorders (HAND). Despite efficient repression of viral replication in the periphery, evidence shows that the virus can remain active in the central nervous system (CNS). This low level of replication is believed to result in a progression of neurocognitive dysfunction in infected individuals. Insufficient viral inhibition in the brain results from the inability of several treatment drugs in crossing the blood-brain barrier (BBB) and reaching therapeutic concentrations in the CNS. The current manuscript discusses several strategies that are being developed to enable therapeutics to cross the BBB, including bypassing BBB, inhibition of efflux transporters, the use of active transporters present at the BBB, and nanotechnology. The increased concentration of therapeutics in the CNS is desirable to prevent viral replication; however, potential side effects of anti-retroviral drugs need also to be taken into consideration.

Proteinuria is common among HIV patients: what are we missing?

OBJECTIVES

HIV-related renal diseases are the leading causes of chronic kidney diseases worldwide. The present study aimed to investigate the prevalence of pathological proteinuria and its risk factors among HIV patients.

METHODS

A review of the medical records of 666 HIV-infected individuals aged 18 years or older in an urban HIV/AIDS clinic based in Porto Alegre in southern Brazil. Overt proteinuria was defined as a protein-to-creatinine ratio greater than 150 mg/g according to Kidney Disease: Improving Global Outcomes.

RESULTS

The prevalence of pathological proteinuria in the present study cohort was 20%. Characteristics associated with pathological proteinuria after univariate analysis included alcohol abuse, hepatitis C virus coinfection, the occurrence of diabetes and therapy including tenofovir. Adjusted residuals analysis indicated an association between pathological proteinuria and both a CD4 lymphocyte count below 200 cells/mm3 and a viral load higher than 1000 copies/mL. Additionally, an absence of pathological proteinuria was associated with a CD4 lymphocyte count higher than 500 cells/mm3. After adjustment for variables with p<0.2 in the univariate analysis using a Poisson regression model, tenofovir-containing regimens and a CD4 lymphocyte count below 200 cells/mm3 were significantly associated with pathological proteinuria.

CONCLUSION

The risk of chronic kidney diseases in this large contemporary cohort of HIV-infected individuals appeared to be attributable to a combination of HIV-related risk factors. In addition to the traditional risk factors cited in the literature, both regimens containing tenofovir and HIV disease severity seem to be associated with chronic kidney diseases in patients with HIV. Assessment of proteinuria constitutes a novel method for chronic kidney disease staging in HIV-infected individuals and may be effectively used to stratify the risk of progression to end-stage renal disease.