The nephrotoxic effects of HAART

Lung Transplantation for People Living With HIV: Promising Mid-term Outcomes

BACKGROUND

With increasing life expectancy, patients with HIV are more commonly acquiring other chronic diseases, such as end-stage lung disease, for which transplant may be the only effective solution. Until recently, HIV infection was considered a contraindication to lung transplant (LTx). As LTx in people living with HIV (PLWH) becomes more common, there remain limited data on outcomes in this population.

METHODS

Using the Organ Procurement and Transplantation Network Standard Transplant Analysis and Research file, we identified LTx recipients with HIV by either serostatus or nucleic acid testing. A control group of confirmed HIV-negative LTx recipients was propensity score matched on age, body mass index, primary diagnosis, and year of transplant. Patient characteristics, transplant parameters, survival, and postoperative outcomes were compared.

RESULTS

Fifty-nine LTx recipients with HIV were identified and compared with 236 HIV-negative controls. Among PLWH, cytomegalovirus status was more frequently positive (76.3% versus 58.9%, P  = 0.014), and the median Lung Allocation Score at match was higher (44 versus 39, P  = 0.004). PLWH were more likely to undergo dialysis postoperatively (18.6% versus 8.9%, P  = 0.033), although other complication rates were similar. Fifty-three percent of LTx for PLWH occurred since 2020. One-year survival for PLWH was 91.2% versus 88.6% for controls ( P  = 0.620). Three-year survival for a smaller subset was also not statistically significant (HIV versus control: 82.6% versus 77.8%, respectively, P  = 0.687).

CONCLUSIONS

There was no difference in 1-y survival for LTx recipients living with HIV compared with a matched control group, supporting this group of patients as viable candidates for LTx.

Methanol Crude Peel Extract of P. granatum Prevents Oxidative Damage in Kidneys of Rats Exposed to Highly Active Antiretroviral Therapy

Background

Highly Active Antiretroviral Therapy (HAART) has been linked to oxidative damage to kidney cells leading to renal disease in people living with HIV/AIDS on HAART treatment. The toxic effects of HAART affect the patients' quality of life leading to poor adherence to their regimen. Therefore, the purpose of this study was to investigate the nephron-protective activity of methanol crude peel extract of Punica granatum (MPEPG) in HAART-administered Wistar rats.

Methods

Thirty male albino Wistar rats weighing between 180-200g were randomly divided into six groups of five rats each. Group one served as normal control and was given distilled water only. Group two serves as a negative control and was given HAART at a dosage of 64 mg/kg. Groups 3 and 4 were given 100 and 400 mg/kg of MPEPG, respectively, while groups 5 and 6 were given MPEPG dosages of 100 and 400 mg/kg along with HAART, respectively, for 40 days. The rats were sacrificed under halothane anaesthesia, and the kidneys were removed for histological evaluation, while blood samples were analyzed for biochemical parameters.

Results

In the HAART (TLD) treated group, there was a significantly high amount of MDA and a lower level of the antioxidant enzymes SOD and CAT. Biochemical analysis revealed that animals treated with HAART (TLD) had significantly higher levels of urea and creatinine, which are biomarkers of kidney damage than the normal control animals. In contrast, all the kidney function markers were returned to normal levels in the HAART-treated group after administration of methanol crude peel extract of P. granatum. The kidney tissues of animals given HAART had considerable structural damage as revealed by histopathological studies. When HAART-exposed rats were treated with MPEPG, both the biochemical and histological results significantly improved.

Conclusion

Methanol crude peel extract of P. granatum provided effective protection against kidney oxidative injury brought on by HAART because of its anti-oxidant and free radical scavenging properties.

COVID-19 and HIV: Clinical Outcomes among Hospitalized Patients in the United States

The concurrence of HIV and COVID-19 yields unique challenges and considerations for healthcare providers, patients living with HIV, and healthcare systems at-large. Persons living with HIV may face a higher risk of acquiring SARS-CoV-2 infection and experiencing worse clinical outcomes compared to those without. Notably, COVID-19 may have a disproportionate impact on historically disadvantaged populations, including African Americans and those stratified in a lower socio-economic status. Using the National Inpatient Sample (NIS) database, we compared patients with a diagnosis of both HIV and COVID-19 and those who exclusively had a diagnosis of COVID-19. The primary outcome was in-hospital mortality. Secondary outcomes were intubation rate and vasopressor use; acute MI, acute kidney injury (AKI); AKI requiring hemodialysis (HD); venous thromboembolism (VTE); septic shock and cardiac arrest; length of stay; financial burden on healthcare; and resource utilization. A total of 1,572,815 patients were included in this study; a COVID-19-positive sample that did not have HIV (n = 1,564,875, 99.4%) and another sample with HIV and COVID-19 (n = 7940, 0.56%). Patients with COVID-19 and HIV did not have a significant difference in mortality compared to COVID-19 alone (10.2% vs. 11.3%, respectively, p = 0.35); however, that patient cohort did have a significantly higher rate of AKI (33.6% vs. 28.6%, aOR: 1.26 [95% CI 1.13-1.41], p < 0.001). Given the complex interplay between HIV and COVID-19, more prospective studies investigating the factors such as the contribution of viral burden, CD4 cell count, and the details of patients' anti-retroviral therapeutic regimens should be pursued.

Kidney tubular injury induced by valproic acid: systematic literature review

BACKGROUND

Valproic acid is prescribed for epilepsy and as prophylaxis for bipolar disorder and migraine headaches. It has also been implicated as a cause of a kidney tubular injury.

METHODS

We undertook a review of the literature to characterize the biochemical and histopathological features of the overt kidney tubular injury and to evaluate the possible existence of a pauci-symptomatic injury. The pre-registered review (CRD42022360357) was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Searches were conducted in Excerpta Medica, the National Library of Medicine, and Web of Science. The gray literature was also considered.

RESULTS

For the final analysis, we retained 36 articles: 28 case reports documented 48 individuals with epilepsy on valproic acid for 7 months or more and presenting with features consistent with an overt kidney tubular injury. The following disturbances were noted: hypophosphatemia (N = 46), normoglycemic glycosuria (N = 46), total proteinuria (N = 45), metabolic acidosis (N = 36), hypouricemia (N = 27), tubular proteinuria (N = 27), hypokalemia (N = 23), and hypocalcemia (N = 8). A biopsy, obtained in six cases, disclosed altered proximal tubular cells with giant and dysmorphic mitochondria. Eight case series addressed the existence of a pauci- or even asymptomatic kidney injury. In the reported 285 subjects on valproic acid for 7 months or more, an isolated tubular proteinuria, mostly N-acetyl-β-glucosaminidase, was often noted.

CONCLUSIONS

Valproic acid may induce an overt kidney tubular injury, which is associated with a proximal tubular mitochondrial toxicity. Treatment for 7 months or more is often associated with a pauci- or oligosymptomatic kidney tubular injury. A higher resolution version of the Graphical abstract is available as Supplementary information.

Bibliometric and visual analysis of nephrotoxicity research worldwide

Background: Nephrotoxicity of drugs contributes to acute kidney injury with high mortality and morbidity, which crucially limits the application and development of drugs. Although many publications on nephrotoxicity have been conducted globally, there needs to be a scientometric study to systematically analyze the intellectual landscape and frontiers research trends in the future.

Methods: Publications on nephrotoxicity from 2011 to 2021 were collected to perform bibliometric visualization using VOSviewer, CiteSpace, and Scimago Graphica software based on the Web of Science Core Collection.

Results: A total of 9,342 documents were analyzed, which were primarily published in the United States (1,861), China (1,724), and Egypt (701). For institutions, King Saud University (166) had the most publications; Food and Chemical Toxicology, PLOS One, and Antimicrobial Agents and Chemotherapy were productive journals, primarily concentrating on the mechanisms of nephrotoxicity and renoprotective in cisplatin and antibiotics, especially in oxidative stress. Burst detection suggested that cisplatin, piperacillin-tazobactam, vancomycin-induced nephrotoxicity, antioxidants, and new biomaterials are frontiers of research.

Conclusion: This study first provides an updated perspective on nephrotoxicity and renoprotective strategies and mechanisms. This perspective may benefit researchers in choosing suitable journals and collaborators and assisting them in the deep understanding of the nephrotoxicity and renoprotective hotspots and frontiers.

Association between frailty phenotype, quantification of plasma HIV-1 RNA, CD4 cell count and HAART in HIV-positive subjects: a systematic review and meta-analysis of observational studies

HIV infection causes a constant activation of the immune system and contributes to an enhanced systemic pro-inflammatory cytokine milieu, which has been associated with premature aging and frailty. We performed a systematic review and meta-analysis to analyze whether the HIV-1 RNA load, CD4+ T-lymphocyte counts and exposure to HAART in HIV-positive subjects are associated with frailty phenotype. Searches were performed in PubMed, SCOPUS, Lilacs, Web of Science, Google Scholar, and OpenThesis databases. We used the odds ratio as a measure of the association. We used either a fixed or random-effects model to pool the results of individual studies depending on the presence of heterogeneity. Eleven studies were included in the review. Data from 8035 HIV-positive subjects were analyzed; 2413 of the subjects had viral load detectable, 981 had a CD4T-cell count <350 cells/μL, and 1342 had HAART exposure information. We found an association between frailty and CD4T-cell count <350 cells/μL (OR 2.68, CI 95% 1.68-4.26, I²= 46%), HIV-1 RNA load detectable (OR 1.71, CI 95% 1.38-2.12, I²= 0%), and protease inhibitor-containing HAART regimen (OR 2.21, CI 95% 1.26-3.89, I² = 0%). Further studies are necessary to evaluate the effects of other factors on the development of clinical features related to frailty.

Drug-Induced Acute Kidney Injury

Medications are a common cause of AKI especially for patients admitted to hospital wards and the intensive care unit. Although drug-related kidney injury occurs through different mechanisms, this review will focus on three specific types of tubulointerstitial injury. Direct acute tubular injury develops from several medications, which are toxic to various cellular functions. Their excretory pathways through the proximal tubules contribute further to AKI. Drug-induced AKI may also develop through induction of inflammation within the tubulointerstitium. Medications can elicit a T cell-mediated immune response that promotes the development of acute interstitial nephritis leading to AKI. Although less common, a third pathway to kidney injury results from the insolubility of drugs in the urine leading to their precipitation as crystals within distal tubular lumens, causing a crystalline-related AKI. Intratubular obstruction, direct tubular injury, and localized inflammation lead to AKI. Clinicians should be familiar with the pathogenesis and clinical-pathologic manifestations of these forms of kidney injury. Prevention and treatment of AKI relies on understanding the pathogenesis and judiciously using these agents in settings where AKI risk is high.

Severe Lactic Acidosis Due to Acute Intoxication by Emtricitabine/Tenofovir Alafenamide

A 46-year-old female with a history of generalized anxiety disorder was admitted after intentional ingestion of an unknown amount of emtricitabine/tenofovir alafenamide (Descovy®) in a suicidal attempt. Patient was emergently intubated secondary to severe agitation and inability to protect airways. Patient developed severe lactic acidosis early in the admission, secondary as to a possible mitochondrial toxicity. Failed attempts to fluid resuscitation with Lactate Ringer®, eventually warranted to start the patient on norepinephrine infusion. Metabolic acidosis remained refractory to bicarbonate bolus and infusion. Hypothermia and hypoglycemia were corrected. Despite the initial approach, the patient remained acidotic, and the nephrology was consulted for emergent continuous renal replacement therapy (CRRT). After three days of intensive care unit stay and CRRT, the patient improved and was successfully decannulated. Her metabolic profile also showed remarkable improvement and the metabolic lactic acidosis resolved. The previous formulation of tenofovir with disoproxil fumarate is associated with severe lactic acidosis due to inhibition of mammalian mitochondrial DNA polymerase. Risk factors include liver cirrhosis, chronic kidney disease, hepatitis B and C coinfection, and metformin use. The new pharmaceutical formulation of tenofovir with alafenamide (TAF) has caused a significant decrease in the incidence of lactic acidosis. However, its real incidence and the usual plasma level to induce toxicity and mitochondrial dysfunction are unknown. The aim of this report is to highlight the risk of severe lactic acidosis with the use of TAF.

Nephrotoxicity of Immune Checkpoint Inhibitors: A Disproportionality Analysis from 2013 to 2020

Nephrotoxicity occasionally occurs during treatment with immune checkpoint inhibitors (ICIs). Few related studies compare the differences between these drugs. This study aimed to systematically characterize nephrotoxicity after ICI initiation. Data were extracted from the US FDA Adverse Event Reporting System (FAERS) database. Disproportionality analysis, including information components (ICs) and reporting odds ratios (RORs), was performed to determine the potential renal toxicity of ICIs. A total of 7,204 reports of renal adverse events (AEs) were identified in the FAERS database. Renal AEs were most commonly reported for nivolumab (46.84%). Strong signals were detected in male patients combined with ICIs. In the clinical application of ICIs, attention should be paid to patients, especially male patients, with acute kidney injury, nephritis, autoimmune nephritis and other nephrotoxic AEs. The use of ICIs is likely to aggravate their condition.

Microscopic and biochemical changes on liver and kidney of Wistar rats on combination antiretroviral therapy: the impact of naringenin and quercetin

Combination antiretroviral therapy (cART), which is a lifelong therapy for people living with human immunodeficiency virus, has been associated with nephrotoxicity and hepatotoxicity leading to its discontinuation. This study aimed at investigating the ameliorative potential of naringenin and quercetin on cART-induced hepatotoxicity and nephrotoxicity. Seventy male Wistar rats (225-260 g) were divided into seven groups as control, cART, naringenin, quercetin, dimethyl sulfoxide (DMSO), naringenin/cART (CN) and quercetin/cART (CQ). cART (24 mg/kg), naringenin (50 mg/kg) and quercetin (50 mg/kg) were dissolved in 1% v/v DMSO and administered orally for 56 days. Combination of cART and bioflavonoids had significant increase in superoxide dismutase (P < 0.05), catalase (P < 0.01), reduced glutathione (P < 0.001) and decreased malondialdehyde (P < 0.001) compared to cART only. Tumor necrosis factor Alpha (TNFα) level increased significantly in cART and CQ (P < 0.01) groups, while others showed no significant changes compared to control. TNFα also significantly decreased in CQ level compared to cART (P < 0.001). In addition, significant increase in creatinine level in cART only indicated progressive renal toxicity. Also, progressive pathological changes including congested blood vessels and hepatocellular necrosis were found in the liver, while the kidney had glomerular atrophy, and tubular distortion in cART-only group. Control, naringenin- and quercetin-treated groups showed normal renal and hepatic cytoarchitecture. These findings elucidate that progressive renal and hepatic toxicity is associated with the continuous use of cART; however, a combination of quercetin and naringenin with cART showed possible potential of ameliorating the damages posed by cART.

Proximal renal tubular function in HIV-infected children on tenofovir disoproxil fumarate for treatment of HIV infection at two tertiary hospitals in Harare, Zimbabwe

BACKGROUND

Renal abnormalities in HIV infected children may be due to the HIV infection or treatment among other factors. Tenofovir disoproxil fumarate (TDF) is associated with proximal renal tubular dysfunction, proteinuria and decrease in glomerular function. Studies in developed countries have shown variable prevalence of proximal renal tubular dysfunction in children on TDF. There are no known studies in developing countries, including Zimbabwe, documenting the proximal tubular function in HIV infected children on TDF. The aim of this study was to assess renal and proximal renal tubular function in HIV infected children receiving TDF and determine factors associated with proximal tubular dysfunction.

METHODS

A descriptive cross-sectional study was conducted in HIV infected patients below 18 years of age attending outpatient clinics at two tertiary hospitals in Harare, who received a TDF-containing antiretroviral regimen for at least six months. Dipstick protein and glucose, serum and urine phosphate and creatinine levels were measured. Fractional excretion of phosphate was calculated. Estimated glomerular filtration rate (eGFR) was calculated using the Schwartz formula. Tubular dysfunction was defined by at least two of the following characteristics: normoglycaemic glycosuria, hypophosphatemia and fractional excretion of phosphate > 18%.

FINDINGS

One hundred and ninety-eight children below 18 years of age were recruited over a period of six months. The prevalence of tubular dysfunction was 0.5%. Normoglycaemic glycosuria occurred in 1 (0.5%), fractional excretion of phosphate >18% in 4 (2%), and hypophosphatemia in 22 [11.1%] patients. Severe stunting was associated with increased risk of hypophosphatemia (OR 9.31 CI (1.18, 80.68) p = 0.03). Reduction in estimated glomerular filtration rate (eGFR) < 90ml/min/1.73m2 and proteinuria was evident in 35.9% and 32.8% of children, respectively. Concurrent TDF and HIV-1 protease inhibitor-based regimen was the only independent factor associated with reduction in GFR (OR 4.43 CI (1.32; 4.89) p = 0.016).

CONCLUSION

Tubular dysfunction was uncommon in Zimbabwean children on a TDF-based ART regimen. Hypophosphatemia, proteinuria and reduction in eGFR were common. Reassessing renal function using more sensitive biomarkers is needed to examine the long-term tolerance of TDF.

HIV, drugs and the kidney

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

Mechanisms of antimicrobial-induced nephrotoxicity in children

Drug-induced nephrotoxicity is responsible for 20% to 60% of cases of acute kidney injury in hospitalized patients and is associated with increased morbidity and mortality in both children and adults. Antimicrobials are one of the most common classes of medications prescribed globally and also among the most common causes of nephrotoxicity. A broad range of antimicrobial agents have been associated with nephrotoxicity, but the features of kidney injury vary based on the agent, its mechanism of injury and the site of toxicity within the kidney. Distinguishing nephrotoxicity caused by an antimicrobial agent from other potential inciting factors is important to facilitate both early recognition of drug toxicity and prompt cessation of an offending drug, as well as to avoid unnecessary discontinuation of an innocuous therapy. This review will detail the different types of antimicrobial-induced nephrotoxicity: acute tubular necrosis, acute interstitial nephritis and obstructive nephropathy. It will also describe the mechanism of injury caused by specific antimicrobial agents and classes (vancomycin, aminoglycosides, polymyxins, antivirals, amphotericin B), highlight the toxicodynamics of these drugs and provide guidance on administration or monitoring practices that can mitigate toxicity, when known. Particular attention will be paid to paediatric patients, when applicable, in whom nephrotoxin exposure is an often-underappreciated cause of kidney injury.

A high likelihood of increase in end-stage renal disease among the Japanese HIV-infected population

Kidneys are affected by human immunodeficiency virus (HIV) infection and its associated therapies. Antiretroviral therapy (ART) has markedly reduced acquired immune deficiency syndrome–related deaths and opportunistic infectious diseases among HIV-infected patients. This contributed to their prolonged survival; however, the improvement in survival has been accompanied by an increase in the incidence of non-infectious chronic complications, including hypertension, metabolic diseases, and chronic kidney disease (CKD). Recent studies showed that estimated prevalence of any CKD and end-stage renal disease (ESRD) among HIV-infected patients is approximately 20% and 0.5%, respectively, in Japan. Both a rapid decrease in renal function and a high positive rate of albuminuria and proteinuria are clinical characteristics of HIV-infected patients. Moreover, considering higher complication rates of hypertension and diabetes compared with non-HIV-infected individuals of the similar aging, HIV-infected patients who develop CKD and ESRD are very likely to increase. Furthermore, as the survival rate is favorable after the initiation of dialysis, the cumulative number of ESRD patients is supposed to increase. The corporation for treatment of HIV-positive hemodialysis patients by general dialysis clinics will be urgently required; however, there still remain some preoccupations and prejudices about HIVper sein Japan, which may provoke hesitation from accepting those patients.

Carbon monoxide: An emerging therapy for acute kidney injury

Treating acute kidney injury (AKI) represents an important unmet medical need both in terms of the seriousness of this medical problem and the number of patients. There is also a large untapped market opportunity in treating AKI. Over the years, there has been much effort in search of therapeutics with minimal success. However, over the same time period, new understanding of the underlying pathobiology and molecular mechanisms of kidney injury have undoubtedly helped the search for new therapeutics. Along this line, carbon monoxide (CO) has emerged as a promising therapeutic agent because of its demonstrated cytoprotective, and immunomodulatory effects. CO has also been shown to sensitize cancer, but not normal cells, to chemotherapy. This is particularly important in treating cisplatin-induced AKI, a common clinical problem that develops in patients receiving cisplatin therapies for a number of different solid organ malignancies. This review will examine and make the case that CO be developed into a therapeutic agent against AKI.

Renal stone composed of ritonavir

Nephrolithiasis is a well-known side effect of many HIV protease inhibitors. However, there have not been reports of stones associated with ritonavir use. Here, we report the case of a 33-year-old woman with HIV on antiretroviral therapy who presented with sharp left flank pain and passed a stone that was later found to contain only ritonavir. Of note, the patient’s treatment regimen had not included ritonavir for 2 years prior to this incidence. This case is notable both for the novel finding of a renal calculus composed entirely of ritonavir and the development of nephrolithiasis years after cessation of the aggravating drug. This finding suggests that patients on ritonavir should be more closely monitored and for longer periods of time for potential lithiasis formation.

Living kidney donation in individuals with hepatitis C and HIV infection: rationale and emerging evidence

PURPOSE OF REVIEW

HIV-infected (HIV+) and hepatitis C virus-infected (HCV+) individuals with end-stage renal disease (ESRD) have decreased access to kidney transplantation. With new opportunities provided by the HIV Organ Policy Equity (HOPE) Act and direct-acting antivirals (DAAs) for HCV, we explore the potential risks and benefits of living donor kidney transplantation from HIV+ or HCV+ donors, from the perspective of both donor health and recipient outcomes.

RECENT FINDINGS

The HOPE Act permits organ donation from both deceased and living HIV+ persons to HIV+ recipients; however, there is only clinical experience with HIV+ deceased donors to date. Empirical evidence demonstrates a low but acceptable risk of ESRD in potential HIV+ living donors without comorbidities who have well-controlled infection in the absence of donation. With the availability of potent DAAs for eradication of HCV infection, growing evidence shows good outcomes with HCV seropositive and/or viremic deceased kidney donors, providing rationale to consider HCV+ living donors.

SUMMARY

HIV+ and HCV+ living donor kidney transplantation may improve access to transplant for vulnerable ESRD populations. Careful evaluation and monitoring are warranted to mitigate potential risks to donors and recipients.

Pharmacology behind Common Drug Nephrotoxicities

Patients are exposed to numerous prescribed and over-the-counter medications. Unfortunately, drugs remain a relatively common cause of acute and chronic kidney injury. A combination of factors including the innate nephrotoxicity of drugs, underlying patient characteristics that increase their risk for kidney injury, and the metabolism and pathway of excretion by the kidneys of the various agents administered enhance risk for drug-induced nephrotoxicity. This paper will review these clinically relevant aspects of drug-induced nephrotoxicity for the clinical nephrologist.

Chronic Kidney Disease in Persons Living with HIV: A Systematic Review

The purpose of our systematic review of research on chronic kidney disease (CKD) in persons living with HIV (PLWH) was to (a) compare and contrast diagnostic criteria for CKD, (b) identify risk factors of CKD in PLWH, and (c) elucidate the prevalence of CKD in PLWH. Keyword searches of PubMed and PsycInfo databases were followed by manual searches of references from 2000 through 2016; 21 studies met inclusion criteria. Sample sizes ranged from 8 to 15,140, with a mean age of 50 years, and represented diverse ethnicities/races and countries of origin. Fourteen studies were cross-sectional, six were cohort studies, and one was a case study. Major risk factors were related to hypertension, diabetes, and age. Prevalence ranged from 2.3% to 53.3% across a variety of countries and patient populations. The wide range in prevalence may have been due to differences in risk factors for the sample populations.

Risk factors and co-morbidities associated with changes in renal function among antiretroviral treatment-naïve adults in South Africa: A chart review

INTRODUCTION

Our systematic scoping review has demonstrated a research gap in antiretroviral treatment (ART) nephrotoxicity as well as in the long-term outcomes of renal function for patients on ART in South Africa. Bearing in mind the high prevalence of human immunodeficiency virus (HIV) in South Africa, this is of great concern.

OBJECTIVES

To determine the risk factors and co-morbidities associated with changes in renal function in HIV-infected adults in South Africa.

METHODS

We conducted a retrospective study of 350 ART-naïve adult patients attending the King Edward VIII HIV clinic, Durban, South Africa. Data were collected at baseline (pre-ART) and at six, 12, 18 and 24 months on ART. Renal function was assessed in the 24-month period using the Modification of Diet in Renal Disease equation and was categorised into normal renal function (estimated glomerular filtration rate [eGFR] ≥ 60), moderate renal impairment (eGFR 30-59), severe renal impairment (eGFR 15-29) and kidney failure (eGFR < 15 mL/min/1.73 m2). Generalised linear models for binary data were used to model the probability of renal impairment over the five time periods, controlling for repeated measures within participants over time. Risk ratios and 95% confidence intervals (CI) were reported for each time point versus baseline.

RESULTS

The cohort was 64% female, and 99% were Black. The median age was 36 years. At baseline, 10 patients had hypertension (HPT), six had diabetes, 61 were co-infected with tuberculosis (TB) and 157 patients had a high body mass index (BMI) with 25.4% being categorised as overweight and 19.4% as obese. The majority of the patients (59.3%) were normotensive. At baseline, the majority of the patients (90.4%) had normal renal function (95% CI: 86% - 93%), 7.0% (CI: 5% - 10%) had moderate renal impairment, 1.3% (CI: 0% - 3%) had severe renal impairment and 1.3% (CI: 0% - 3%) had renal failure. As BMI increased by one unit, the risk of renal impairment increased by 1.06 (CI: 1.03-1.10) times. The association of HPT with abnormal renal function was found to be insignificant, p > 0.05. The vast majority of patients were initiated on tenofovir disoproxil fumarate (TDF) (90.6%), in combination with lamivudine (3TC) (100%) and either efavirenz (EFV) (56.6%) or nevirapine (NVP) (43.4%).

CONCLUSION

This study reports a low prevalence of baseline renal impairment in HIV-infected ART-naïve outpatients. An improvement in renal function after the commencement of ART has been demonstrated in this population. However, the long-term outcomes of patients with HIV-related renal disease are not known.

A Two-Way Steady-State Pharmacokinetic Interaction Study of Doravirine (MK-1439) and Dolutegravir

INTRODUCTION

Doravirine, a non-nucleoside reverse-transcriptase inhibitor in development for the treatment of patients with human immunodeficiency virus-1 infection, has potential to be used concomitantly in antiretroviral therapy with dolutegravir, an integrase strand transfer inhibitor. The pharmacokinetic interactions between these drugs were therefore assessed.

METHODS

Oral formulations of doravirine and dolutegravir were dosed both individually and concomitantly once daily in healthy adults. Twelve subjects (six were male), 23-42 years of age, were enrolled and 11 completed this phase I, open-label, three-period, fixed-sequence study per protocol; one subject was discontinued for a positive cotinine test at admission to period 2. In period 1, dolutegravir 50 mg was administered for 7 days. After a 7-day washout, doravirine 200 mg was dosed for 7 days in period 2, followed (without washout) by both doravirine and dolutegravir simultaneously for 7 days in period 3. Plasma samples were taken to determine dolutegravir and doravirine concentrations.

RESULTS

The steady-state concentration 24 h post-dose (C₂₄) of dolutegravir was not substantially altered by co-administration of doravirine multiple doses; area under the plasma concentration-time curve from dosing to 24 h post-dose (AUC_0-24), maximum concentration (C _max), and C₂₄ geometric mean ratios were 1.36, 1.43, and 1.27, respectively. The pharmacokinetics of doravirine was not affected by multiple doses of dolutegravir (geometric mean ratios: 1.00, 0.98, and 1.06 for AUC_0-24, C₂₄, and C _max, respectively). Both drugs were generally well tolerated.

CONCLUSION

The results of this study demonstrate that concomitant administration of doravirine and dolutegravir in healthy subjects causes no clinically significant alteration in the pharmacokinetic and safety profiles of the two drugs, thereby supporting further evaluation of co-administration of these agents for human immunodeficiency virus-1 treatment.

Drug-Induced Kidney Stones and Crystalline Nephropathy: Pathophysiology, Prevention and Treatment

Drug-induced calculi represent 1-2% of all renal calculi. The drugs reported to produce calculi may be divided into two groups. The first one includes poorly soluble drugs with high urine excretion that favour crystallisation in the urine. Among them, drugs used for the treatment of patients with human immunodeficiency, namely atazanavir and other protease inhibitors, and sulphadiazine used for the treatment of cerebral toxoplasmosis, are the most frequent causes. Besides these drugs, about 20 other molecules may induce nephrolithiasis, such as ceftriaxone or ephedrine-containing preparations in subjects receiving high doses or long-term treatment. Calculi analysis by physical methods including infrared spectroscopy or X-ray diffraction is needed to demonstrate the presence of the drug or its metabolites within the calculi. Some drugs may also provoke heavy intra-tubular crystal precipitation causing acute renal failure. Here, the identification of crystalluria or crystals within the kidney tissue in the case of renal biopsy is of major diagnostic value. The second group includes drugs that provoke the formation of urinary calculi as a consequence of their metabolic effects on urinary pH and/or the excretion of calcium, phosphate, oxalate, citrate, uric acid or other purines. Among such metabolically induced calculi are those formed in patients taking uncontrolled calcium/vitamin D supplements, or being treated with carbonic anhydrase inhibitors such as acetazolamide or topiramate. Here, diagnosis relies on a careful clinical inquiry to differentiate between common calculi and metabolically induced calculi, of which the incidence is probably underestimated. Specific patient-dependent risk factors also exist in relation to urine pH, volume of diuresis and other factors, thus providing a basis for preventive or curative measures against stone formation.

Role of kidney biomarkers [Kidney injury molecule-1, Calbindin, Interleukin-18 and Monocyte chemoattractant protein-1] in HIV associated pre-eclampsia

OBJECTIVE

Both HIV infection and pre-eclampsia (PE) are associated with considerable maternal mortality in South Africa. This study was designed to compare the urinary levels of kidney injury molecule-1 (KIM-1), calbindin, interleukin-18 (IL-18), and monocyte chemoattractant protein-1 (MCP-1) in HIV associated normotensive and preeclamptic pregnancies.

METHODS

Following ethical approval and written consent, urine samples were collected from HIV negative (HIV -ve) normotensive pregnant (n = 19), HIV positive (HIV +ve) normotensive pregnant (n = 19), HIV -ve pre-eclamptic (n = 19) and HIV +ve pre-eclamptic (n = 19) women. The concentrations of KIM-1, calbindin, IL-18 and MCP-1 were assessed using the Bioplex technology.

RESULTS

In contrast to IL-18 (p > 0.05) and MCP-1 (p > 0.05), the concentrations of KIM-1 (p = 0.02) and calbindin (p = 0.02) were significantly higher in PE compared to normotensive pregnancies, irrespective of HIV status. Based on HIV status, all 4 analytes were similar between HIV+ve and HIV-ve groups. Urinary KIM-1 levels in the HIV -ve pre-eclamptics were significantly higher than those in the HIV -ve women with normal pregnancies (p = 0.007). The maternal hypertension and/or HIV profile has no marked impact on the fetal weight.

CONCLUSION

Our results demonstrate an increase in the urinary level of kidney injury molecule-1 and calbindin in PE, implicating their possible value as biomarkers of kidney injury. We observed no differences in the levels of KIM-1, IL-18, MCP-1 and calbindin based on HIV status. We propose that studies with larger sample sizes using these markers be conducted to establish their use as markers of diagnosing kidney injury in PE.

The renal pathological findings in Japanese HIV-infected individuals with CKD: a clinical case series from a single center

BACKGROUND

Chronic kidney diseases (CKD) have emerged as a significant cause of morbidity and mortality in patients infected with human immunodeficiency virus (HIV). However, the detailed study of renal pathological findings currently remains unclear in these Japanese patients.

METHODS

A retrospective cohort study was undertaken to investigate renal pathological findings between January 1996 and July 2016. Our study included 20 Japanese HIV-infected patients with CKD; 10 cases had undergone renal biopsies, and 10 cases had undergone autopsies, respectively. Moreover, in the 10 biopsied patients, their clinical courses as well as renal outcomes after renal biopsy were also reviewed.

RESULTS

All of the patients had received combination antiretroviral therapy (cART). The 10 biopsy cases (mean age, 54 ± 14 years and duration of cART, 8 ± 5 years) included three cases of diabetic nephropathy (DMN), two of IgA nephropathy, two of cART-induced tubulointerstitial nephritis (TIN), one of minimal change disease, one case of only finding intrarenal arterioles, and one case without abnormal findings. Among those patients, their clinical courses were preferable except for in the DMN cases. In the autopsy cases (mean age, 52 ± 10 years and duration of cART, 5 ± 5 years), no distinct mesangial or membranous abnormalities were detected. Mild to moderate tubulointerstitial atrophies were observed in six cases. Intrarenal arteriosclerosis was identified in nine cases, and the proportion of global glomerulosclerosis seen was 8.4 ± 12.5%/100 glomeruli.

CONCLUSION

DMN and cART-induced TIN was noted in the biopsy cases. In the autopsy cases, renal arteriosclerosis, global glomerulosclerosis, and tubulointerstitial atrophy were remarkable. Early diagnosis of kidney diseases should be crucial to introduce optimal management, including controlling rigorous comorbidities and appropriate use of cART, to prevent further progression of CKD.

Impact of protease inhibitors on the evolution of urinary markers: Subanalyses from an observational cross-sectional study

Kidney injury (defined as the presence of albuminuria, proteinuria, glycosuria [without hyperglycemia], hematuria, and/or renal hypophosphatemia) is an emerging problem in human immunodeficiency virus (HIV)-infected patients, although few data are available on the role of protease inhibitors (PIs) in this condition.To determine the time to kidney injury in a cohort of HIV-infected patients receiving a PI-containing regimen.We report the results of a subanalysis of a published cross-sectional study. The subanalysis included only patients receiving PI-containing regimens for more than 6 months (377 of the overall 970 patients). We determined associated factors and constructed receiver operating characteristic curves to estimate time to kidney injury depending on the PI used.The percentage of patients with kidney injury was 27.7% for darunavir, 27.9% for lopinavir, and 30% for atazanavir. Time to kidney injury was as follows: 229 days for atazanavir/ritonavir (area under the curve [AUC], 0.639; sensitivity, 0.89; specificity, 0.41); 332 days for atazanavir/ritonavir plus tenofovir (AUC, 0.603; sensitivity, 0.75; and specificity, 0.29); 318 days for nonboosted atazanavir (AUC, 0.581; sensitivity, 0.89; and specificity, 0.29); 478 days for lopinavir/ritonavir (AUC, 0.566; sensitivity, 0.864; and specificity, 0.44); 1339 days for lopinavir/ritonavir plus tenofovir (AUC, 0.667; sensitivity, 0.86; and specificity, 0.77); 283 days for darunavir/ritonavir (AUC, 0.523; sensitivity, 0.80; and specificity, 0.261); and 286 days for darunavir/ritonavir plus tenofovir (AUC, 0.446; sensitivity, 0.789; and specificity, 0.245). The use of lopinavir/ritonavir without tenofovir was a protective factor (odds ratio = 1.772; 95%CI, 1.070-2.93; P = 0.026).For all PIs, the percentage of patients with kidney injury exceeded 27%, irrespective of tenofovir use. The longest time to kidney injury was recorded with lopinavir/ritonavir. These results demonstrate the need for renal monitoring, including urine samples, in patients receiving a PI-based regimen, even when tenofovir is not used concomitantly.

Polymorphisms associated with renal adverse effects of antiretroviral therapy in a Southern Brazilian HIV cohort

OBJECTIVE

This study evaluated the impact of seven single nucleotide polymorphisms in five candidate genes (ABCB1, ABCC2, ABCC4, SLC22A6, and SLC22A11) in relation to nephrotoxicity associated with highly active antiretroviral therapy (HAART) in HIV-infected individuals.

METHODS

The following single nucleotide polymorphisms were genotyped by real-time PCR: ABCB1 rs1045642, ABCC2 rs717620 and rs2273697, ABCC4 rs1751034 and rs3742106, SLC22A6 rs11568626, and SLC22A11 rs11231809 in 507 HIV-infected patients from the city of Porto Alegre, Southern Brazil, receiving HAART for, at least, 1 year.

RESULTS

From the 507 HIV-infected patients recruited, 19.1% presented a reduction in estimated glomerular filtration rate (eGFR). A total of 16 (3.2%) patients fulfilled the criteria for chronic kidney disease (defined as eGFR<60 ml/min/1.73 m). Individuals carrying at least one T allele of ABCC2 -24 C>T (rs717620) presented lower eGFR than C/C homozygotes (104 ± 22 vs. 108 ± 22 ml/min/1.73 m, independent-samples t-test, P=0.040). In multivariate analysis, the predictors associated with decreased eGFR were time of treatment, tenofovir use, atazanavir/ritonavir use, and carrying one T allele of ABCC2 -24 C>T.

CONCLUSION

Our data support the importance of genetic factors in the etiology of nephrotoxicity in patients treated with HAART. Studies to verify treatment implications of genotyping before HAART initiation may be advisable to guide the selection of an appropriate antiretroviral therapy regimen.

Kidney-on-a-chip technology for renal proximal tubule tissue reconstruction

The renal proximal tubule epithelium is responsible for active secretion of endogenous and exogenous waste products from the body and simultaneous reabsorption of vital compounds from the glomerular filtrate. The complexity of this transport machinery makes investigation of processes such as tubular drug secretion a continuous challenge for researchers. Currently available renal cell culture models often lack sufficient physiological relevance and reliability. Introducing complex biological culture systems in a 3D microfluidic design improves the physiological relevance of in vitro renal proximal tubule epithelium models. Organ-on-a-chip technology provides a promising alternative, as it allows the reconstruction of a renal tubule structure. These microfluidic systems mimic the in vivo microenvironment including multi-compartmentalization and exposure to fluid shear stress. Increasing data supports that fluid shear stress impacts the phenotype and functionality of proximal tubule cultures, for which we provide an extensive background. In this review, we discuss recent developments of kidney-on-a-chip platforms with current and future applications. The improved proximal tubule functionality using 3D microfluidic systems is placed in perspective of investigating cellular signalling that can elucidate mechanistic aberrations involved in drug-induced kidney toxicity.

HIV and chronic kidney disease

Chronic kidney disease (CKD) is a frequent complication of HIV infection, occurring in 3.5 - 48.5%, and occurs as a complication of HIV infection, other co-morbid disease and infections and as a consequence of therapy of HIV infection and its complications. The classic involvement of the kidney by HIV infection is HIV-associated nephropathy (HIVAN), occurring typically in young adults of African ancestry with advanced HIV disease in association with APOL1 high-risk variants. HIV-immune complex disease is the second most common diagnosis obtained from biopsies of patients with HIV-CKD. CKD is mediated by factors related to the virus, host genetic predisposition and environmental factors. The host response to HIV infection may influence disease phenotype through activation of cytokine pathways. With the introduction of antiretroviral therapy (ART), there has been a decline in the incidence of HIVAN, with an increasing prevalence of focal segmental glomerulosclerosis. Several studies have demonstrated the overall improvement in kidney function when initiating ART for HIV CKD. Progression to end stage kidney disease has been reported to be more likely when high grade proteinuria, severely reduced eGFR, hepatitis B and/C co-infection, diabetes mellitus, extensive glomerulosclerosis, and chronic interstitial fibrosis are present. Improved renal survival is associated with use of renin angiotensin system blockers and viral suppression. Many antiretroviral medications are partially or completely eliminated by the kidney and require dose adjustment in CKD. Certain drug classes, such as the protease inhibitors and the non-nucleoside reverse transcriptase inhibitors, are metabolized by the liver and do not require dose adjustment. HIV-infected patients requiring either hemo- or peritoneal dialysis, who are stable on ART, are achieving survival rates comparable to those of dialysis patients without HIV infection. Kidney transplantation has been performed successfully in HIV-infected patients; graft and patient survival appears to be similar to that of HIV-uninfected recipients. Early detection of kidney disease by implementation of screening on diagnosis of HIV infection and annual screening thereafter will have an impact on the burden of disease, together with access to ART to those who require it. Programs for prevention of HIV infection are essential to prevent this lethal disease.

Associations between vitamin D metabolites, antiretroviral therapy and bone mineral density in people with HIV

RATIONALE

To see if vitamin D and antiretroviral therapy are associated with bone mineral density (BMD) in people with HIV.

RESULT

Lower hip BMD was associated with tenofovir (an antiretroviral medicine) in those with 25(OH)D ≥50 nmol/L.

SIGNIFICANCE

The relationship between antiretroviral therapy and hip BMD differs depending on vitamin D status.

INTRODUCTION

People with HIV have an increased risk of low BMD and fractures. Antiretroviral therapy contributes to this increased risk. The aim of this study was to evaluate associations between vitamin D metabolites and antiretroviral therapy on BMD.

METHODS

The simplification of antiretroviral therapy with tenofovir-emtricitabine or abacavir-lamivudine trial (STEAL) was an open-label, prospective randomised non-inferiority study that compared simplification of current nucleoside reverse transcriptase inhibitors (NRTIs) to fixed-dose combination tenofovir-emtricitabine (TDF-FTC) or abacavir-lamivudine. Serum 25(OH)D and 1,25(OH)2D were measured in 160 individuals (90 receiving TDF-FTC, 70 receiving other NRTIs) at baseline from this study. Multivariable linear regression models were constructed to evaluate the covariates of 1,25(OH)2D and BMD.

RESULTS

Protease inhibitor use (p = 0.02) and higher body mass index (BMI) (p = 0.002) were associated with lower 1,25(OH)2D levels in those with 25(OH)D <50 nmol/L. However, TDF-FTC use (p = 0.01) was associated with higher 1,25(OH)2D levels, but only in those with 25(OH)D ≥50 nmol/L. White ethnicity (p = 0.02) and lower BMI (p < 0.001) in those with 25(OH)D <50 nmol/L and with TDF-FTC use (p = 0.008) in those with 25(OH)D ≥50 nmol/L were associated with lower hip BMD. TDF-FTC use, higher serum calcium and serum βCTX, winter, and lower bone-specific alkaline phosphatase (BALP) and BMI were associated with lower lumbar spine BMD.

CONCLUSION

TDF-FTC use (versus non-TDF-FTC use) was associated with lower hip BMD, and this difference was more pronounced in those with 25(OH)D ≥50 nmol/L. Serum 25(OH)D <50 nmol/L was associated with lower hip BMD in all participants. Therefore, the associations between antiretroviral therapy and hip BMD differ depending on vitamin D status.

Role of endoplasmic reticulum stress in drug-induced toxicity

Drug‐induced toxicity is a key issue for public health because some side effects can be severe and life‐threatening. These adverse effects can also be a major concern for the pharmaceutical companies since significant toxicity can lead to the interruption of clinical trials, or the withdrawal of the incriminated drugs from the market. Recent studies suggested that endoplasmic reticulum (ER) stress could be an important event involved in drug liability, in addition to other key mechanisms such as mitochondrial dysfunction and oxidative stress. Indeed, drug‐induced ER stress could lead to several deleterious effects within cells and tissues including accumulation of lipids, cell death, cytolysis, and inflammation. After recalling important information regarding drug‐induced adverse reactions and ER stress in diverse pathophysiological situations, this review summarizes the main data pertaining to drug‐induced ER stress and its potential involvement in different adverse effects. Drugs presented in this review are for instance acetaminophen (APAP), arsenic trioxide and other anticancer drugs, diclofenac, and different antiretroviral compounds. We also included data on tunicamycin (an antibiotic not used in human medicine because of its toxicity) and thapsigargin (a toxic compound of the Mediterranean plant Thapsia garganica) since both molecules are commonly used as prototypical toxins to induce ER stress in cellular and animal models.

A Human Renal Proximal Tubule Cell Line with Stable Organic Anion Transporter 1 and 3 Expression Predictive for Antiviral-Induced Toxicity

Drug-induced nephrotoxicity still hampers drug development, because current translation from in vitro or animal studies to human lacks high predictivity. Often, renal adverse effects are recognized only during clinical stages of drug development. The current study aimed to establish a robust and a more complete human cell model suitable for screening of drug-related interactions and nephrotoxicity. In addition to endogenously expressed renal organic cation transporters and efflux transporters, conditionally immortalized proximal tubule epithelial cells (ciPTEC) were completed by transduction of cells with the organic anion transporter (OAT) 1 or OAT3. Fluorescence-activated cell sorting upon exposure to the OAT substrate fluorescein successfully enriched transduced cells. A panel of organic anions was screened for drug-interactions in ciPTEC-OAT1 and ciPTEC-OAT3. The cytotoxic response to the drug-interactions with antivirals was further examined by cell viability assays. Upon subcloning, concentration-dependent fluorescein uptake was found with a higher affinity for ciPTEC-OAT1 (K_m = 0.8 ± 0.1 μM) than ciPTEC-OAT3 (K_m = 3.7 ± 0.5 μM). Co-exposure to known OAT1 and/or OAT3 substrates (viz. para-aminohippurate, estrone sulfate, probenecid, furosemide, diclofenac, and cimetidine) in cultures spanning 29 passage numbers revealed relevant inhibitory potencies, confirming the robustness of our model for drug-drug interactions studies. Functional OAT1 was directly responsible for cytotoxicity of adefovir, cidofovir, and tenofovir, while a drug interaction with zidovudine was not associated with decreased cell viability. Our data demonstrate that human-derived ciPTEC-OAT1 and ciPTEC-OAT3 are promising platforms for highly predictive drug screening during early phases of drug development.

A Single-Nucleotide Polymorphism in ABCC4 Is Associated with Tenofovir-Related Beta2-Microglobulinuria in Thai Patients with HIV-1 Infection

Background

In Thailand, the combined generic anti-retroviral drug stavudine/lamivudine/nevirapine (d4T/3TC/NVP) has been used to treat human immunodeficiency virus (HIV)-infected individuals since 2001. Due to relatively frequent adverse effects, d4T gradually has been replaced with tenofovir disoproxil fumarate (TDF). Although the frequency of adverse drug effects with TDF is lower than that with d4T, TDF is known to induce kidney dysfunction, especially in the proximal tubules. It has been reported that renal tubular transporters, including members of the multi-drug resistant (MDR) protein family, are implicated in tenofovir extrusion and may, therefore, confer susceptibility to TDF-induced kidney tubular dysfunction (KTD). We have explored the association between KTD and polymorphisms in genes that encode adenosine triphosphate-binding cassette (ABC)-type MDRs.

Methods

HIV-infected patients receiving TDF-containing antiretroviral regimens for at least one year were enrolled in the study. The levels of beta2-microglobulin in urine and creatinine (Cr) were measured. Three single-nucleotide polymorphisms, ABCC2 C-24T (rs717620), ABCC2 G1429A (rs2273697), and ABCC4 T4976C (rs1059751), were analyzed using TaqMan SNP genotyping assays.

Results

A total of 273 HIV-infected patients were recruited. The median number of years of TDF treatment was 5.04 with interquartile range (IQR) of 3.9–6.7. Despite the length of treatment with TDF, 98.5% patients maintained an estimated glomerular filtration rate (eGFR) of >60 mL/min as calculated by the CKD-EPI formula. Fifty-four patients (19.8%) showed beta2-microglobulinuria (median 2636 μg/g Cr with IQR of 1519–13197 μg/g Cr). The allele frequency of ABCC4 T4976C among those 54 patients was 0.602, compared to 0.475 among the 219 remaining patients (p = 0.018).

Conclusions

Approximately 20% of HIV-infected patients receiving TDF showed beta2-microglobulinuria. The C allele at position 4976 of the ABCC4 gene was associated with beta2-microglobulinuria in this population. This polymorphism may help to identify patients at greater risk for developing TDF-associated KTD.

Renal transplantation in human immunodeficiency virus-positive patients: a report of four cases

INTRODUCTION

Renal transplantation (RT) in patients infected with human immunodeficiency virus (HIV) has significantly improved under the advent of combined antiretroviral therapy (cART). The authors describe their experience in RT in patients with HIV from September 2010 to June 2013.

CASES REPORT

Four patients underwent transplantation (3 with HIV-1 and 1 with HIV-2), three patients were male, and one was black. None were coinfected with hepatitis B virus (HBV) or hepatitis C virus (HCV). Etiology of kidney disease was HIV-associated nephropathy (2 patients), immunoglobulin (Ig)A nephropathy, and unknown. Average age at RT was 51 (range, 41-63) years. No patient was of high immunologic risk. Immunosuppression consisted of basiliximab for induction and prednisolone, tacrolimus (TAC), and mycophenolate mofetil for maintenance. TAC levels varied considerably in the early days (8.5-46 ng/mL), requiring major adjustments in TAC dose. Only the HIV-2 patient had delayed graft function. The follow-up of patients with HIV-1 was 37, 19, and 16 months, and 3 months for the HIV-2 patient. CD4+ T cells decreased in the early days after transplantation with subsequent improvement, along with persistent virological suppression. In the HIV-1 group there were no major infectious, cardiovascular, or neoplastic complications. Nevertheless, the HIV-2 patient died 3 months after RT due to H1N1 pneumonia complicated by pulmonary aspergillosis. Average estimated (CKD- EPI) glomerular filtration rate (eGFR) at 6 months was 85.6 mL/min/1.73 m(2).

CONCLUSION

Besides the difficulty in adjusting calcineurin inhibitors levels due to its interaction with antiretroviral therapy, namely with protease inhibitors, no patient had acute rejection. Furthermore, all patients presented an excellent control of viro-immunologic parameters. At the last follow-up neither cardiovascular events nor neoplastic complications were observed. Our results highlight the favorable outcome of RT in HIV-1-infected patients. The HIV-2 patient died due to severe infection, and the clinical management and potential benefit of RT in HIV-2-infected patients needs further study.

Epidemiology, clinical characteristics, and management of chronic kidney disease in human immunodeficiency virus-infected patients

Antiretroviral therapy has markedly reduced acquired immune deficiency syndrome-related deaths and opportunistic infectious diseases. This has resulted in prolonged survival of individuals infected with the human immunodeficiency virus (HIV). However, this improvement in survival has been accompanied by an increase in the incidence of chronic kidney disease (CKD) and end-stage renal disease. CKD is now epidemic among HIV-infected populations in both Western and Eastern countries. Risk factors associated with CKD in HIV-infected populations include aging, hypertension, diabetes mellitus, co-infection with hepatitis C virus, a low CD4 cell count, and a high HIV viral load. Clinical experience has shown that HIV-infected individuals often have one or more concurrent risk factors for CKD. The cumulative effect of multiple risk factors on the development of CKD should be noted in this population. Glomerular disease directly related to HIV infection, so-called HIV-associated nephropathy, remains an important cause of CKD among a limited HIV population of African descent, but is less likely to be common among other urban HIV populations. The impact of exposure to nephrotoxic antiretroviral agents on the development of kidney disease is both an old and a new concern. In particular, the association of tenofovir with kidney tubular injury has been an area of great interest. The findings regarding tenofovir's adverse effect on long-term kidney function vary among studies. The early identification and treatment of CKD is recommended for reducing the burden of patients requiring dialysis in HIV-infected populations. Periodic monitoring of urinary concentrations of albumin, protein, and tubular injury markers such as low-molecular-weight proteins may be useful for the early diagnosis of patients at risk for incident CKD. This review focuses on recent epidemiology, clinical characteristics, and management of CKD in a contemporary HIV-infected population.

Renal transplantation in human immunodeficiency virus (HIV)-positive children

Renal transplantation is being performed in adult human immunodeficiency virus (HIV)-positive patients and increasingly in paediatric patients as well. A multidisciplinary team involving an infectious disease professional is required to assist with HIV viral-load monitoring and in choosing the most appropriate highly active antiretroviral therapy (HAART). Drug interactions complicate immunosuppressant therapy and require careful management. The acute rejection rates appear to be similar in adults to those in noninfective transplant recipients. Induction with basiliximab and calcineurin-based immunosuppression appears to be safe and effective in these recipients. Prophylaxis is advised for a variety of infections and may need life-long administration, especially in children. Organ shortage remains a significant problem, and kidneys from deceased HIV-positive donors have been used successfully in a small study population. Overall, with careful planning and close follow-up, successful renal transplantation for paediatric HIV-infected recipients is possible.

Clinical Treatment Options Infectious Diseases: Update on PrEP Implementation, Adherence, and Advances in Delivery

Pre-exposure prophylaxis (PrEP) is an effective and evidence-based HIV-prevention option and is recommended for individuals with substantial risk for HIV infection [1]. Randomized controlled trials have demonstrated that daily oral PrEP dramatically reduces the risk of HIV infection when it is taken as directed. Concerns regarding widespread emergence of antiretroviral resistance attributable to PrEP and behavioral disinhibition have to date not been observed in clinical trials and open-label demonstration projects. PrEP has great potential as part of an HIV risk reduction strategy and barriers to wider implementation including community education, prescriber availability, and elimination of financial barriers should be aggressively pursued. Adherence is critical to PrEP efficacy and has varied across study populations; developing and refining ways of measuring and supporting adherence is essential to the success of PrEP. Evaluation of long-acting medications and alternative formulations for PrEP is underway and may lead to the wider implementation and impact of PrEP.

Drug interactions and antiretroviral drug monitoring

Owing to the improved longevity afforded by combination antiretroviral therapy (cART), HIV-infected individuals are developing several non-AIDS-related comorbid conditions. Consequently, medical management of the HIV-infected population is increasingly complex, with a growing list of potential drug-drug interactions (DDIs). This article reviews some of the most relevant and emerging potential interactions between antiretroviral medications and other agents. The most common DDIs are those involving protease inhibitors or non-nucleoside reverse transcriptase inhibitors, which alter the cytochrome P450 enzyme system and/or drug transporters such as p-glycoprotein. Of note are the new agents for the treatment of chronic hepatitis C virus infection. These new classes of drugs and others drugs that are increasingly used in this patient population represent a significant challenge with regard to achieving the goals of effective HIV suppression and minimization of drug-related toxicities. Awareness of DDIs and a multidisciplinary approach are imperative in reaching these goals.

Protease Inhibitors and Renal Function in Patients with HIV Infection: a Systematic Review

INTRODUCTION

Despite antiretroviral (ARV) therapy reducing renal disease in human immunodeficiency virus overall, there is concern that certain ARVs, particularly tenofovir disoproxil fumarate (TDF) with or without a boosted protease inhibitor (PI), may reduce renal function over time. It is not known whether effects seen with PI-based regimens are independent, result from interactions with TDF coadministration, or are artefactual owing to inhibition of renal tubular creatinine transport by ritonavir or cobicistat pharmacoenhancement. The aim of this review was to conduct a systematic review of studies, weighted toward high-quality evidence, examining changes in renal function over time with PI-based regimens.

METHODS

PubMed, Embase, and Medline databases and conference abstracts were searched using pre-defined terms for English language articles, published up to and including August 12, 2013, describing changes in renal function over time with PI-based regimens. All available randomized controlled trials (RCTs) were selected; however, to reduce bias, only observational studies recruiting from more than one center and analyzing data from more than 1,000 patients were included. Evidence was qualitatively evaluated according to levels established by the Oxford Centre for Evidence-Based Medicine (OCEBM).

RESULTS

A total of 2,322 articles were retrieved by the initial search. Of these, 37 were selected for full review, comprising 24 RCTs (OCEBM Level 1 evidence: 4 reports of fully double-blinded or blinded with respect to the PI component). The remaining 20 RCTs and 13 observational studies qualified as OCEBM Level 2 evidence. Level 1 evidence showed initial but non-progressive increases in serum creatinine and corresponding decreases in estimated glomerular filtration rate (eGFR), suggesting an effect on renal tubular transport of creatinine. Level 2 evidence suggested that atazanavir and lopinavir especially in combination with TDF were associated with non-progressive reductions in eGFR over time, with a decreased risk for the development of chronic kidney disease (CKD) on cessation and without the development of advanced CKD or end-stage renal disease (ESRD); whether these reductions were independent or associated with interactions with coadministered TDF could not be established with certainty. Data on darunavir were insufficient to draw any conclusions. The principal limitation of the reviewed studies was the lack of standardization of creatinine measurements in virtually all studies and the lack of corroborative data on changes in proteinuria or other indices of renal function.

DISCUSSION

In this review, there was little evidence for progressive changes in eGFR, or the development of advanced CKD, or ESRD with lopinavir or atazanavir. Further long-term studies, employing a wide range of validated renal function assessments, are required to fully evaluate potential association of PIs with CKD.

Bone and kidney toxicity induced by nucleotide analogues in patients affected by HBV-related chronic hepatitis: a longitudinal study

OBJECTIVES

Nucleotide analogues may promote renal and bone toxicity. The aim of the present study was to evaluate markers of osteorenal toxicity in patients affected by hepatitis B virus-related chronic hepatitis treated with lamivudine plus adefovir who were switched to tenofovir.

PATIENTS AND METHODS

We evaluated 60 consecutive patients at the time of the switch of treatment and after 1, 3, 6, 9 and 12 months. The mean baseline estimated glomerular filtration rate (eGFR) was 89.3 ± 19.0 mL/min/1.73 m(2).

RESULTS

During the study period we observed a reduction in mean eGFR up to 6 months after switching to tenofovir, and this remained stable for the last two timepoints. At the end of study, the mean eGFR was 82.6 ± 21.5 mL/min/1.73 m(2), a reduction of 7.5%. The mean baseline proteinuria was 202.6 ± 237.6 mg/24 h. Microhaematuria was observed in 22.6% of patients and hypophosphataemia in 18.6%. After 1 month of tenofovir, we observed a worsening of serum phosphate and parathyroid hormone levels, haemoglobinuria and 24 h proteinuria. After 3 and 12 months of tenofovir, these data tended to recover to baseline levels. A total of 92.6% of patients at baseline had hypovitaminosis D. After supplementation with cholecalciferol, this percentage decreased significantly. We observed a reduced bone mineral density (BMD) in 52.7% of patients at baseline; this increased to 77.8% after 6 months of tenofovir, but at the last timepoint the percentage of patients with a reduced BMD had fallen to a level above the baseline.

CONCLUSIONS

In conclusion, patients exposed to lamivudine plus adefovir showed relevant osteorenal damage. The switch to tenofovir provoked a slight reduction in eGFR that stabilized after 6 months. The reduced BMD at baseline did not worsen under tenofovir treatment.

Renal impairment in HIV-infected patients initiating tenofovir-containing antiretroviral therapy regimens in a Primary Healthcare Setting in South Africa

OBJECTIVE

Long-term use of tenofovir disoproxil fumarate is associated with declines in glomerular function and chronic kidney disease in HIV-infected patients. We aimed to assess the prevalence and incidence of renal impairment in a primary care setting in sub-Saharan Africa.

METHODS

We analysed data from 1092 HIV-infected patients initiating tenofovir at a primary care clinic in Cape Town, South Africa. Renal function was assessed for the first 12 months on ART by estimating glomerular filtration rate (eGFR) calculated using the Cockroft-Gault equation categorised into normal, mild, moderate and severe reduction in renal function based on values >90, 60-89, 30-59 and <30 ml/min/1.73 m(2) , respectively. Associations were assessed using logistic regression, and average GFR trajectory over time was modelled using linear mixed-effects models.

RESULTS

The cohort consisted of 62% women; median age was 34 years (IQR 29; 41 years). The majority had normal renal function pre-ART (79%), 19% had mildly reduced GFR, and 2% had moderate renal impairment. Older age, more advanced WHO stage and anaemia were independently associated with prevalent renal impairment. On average, estimated glomerular function improved over the first year on tenofovir [1.10 ml/min/1.73 m(2) average increase over 12 months (95% CI: 0.80; 1.40)]. Male gender, anaemia and immunosuppression (WHO Stage III/IV and CD4 cell counts <100 cells/mm(3) ) were associated with lower average eGFR levels over time. Overall, 3% developed eGFR <50 ml/min/1.73 m(2) during this period. Serum creatinine tests conducted before 4 months on ART had low predictive value for predicting change in eGFR after a year on ART.

CONCLUSION

Generally, renal function improved in HIV-infected adults initiating ART in this primary healthcare setting during the first year on ART. While monitoring of renal function is recommended in the first 4 months on ART, renal impairment appears uncommon during the first 12 months of tenofovir-containing ART in primary care populations.

End-stage renal disease among HIV-infected adults in North America

BACKGROUND

Human immunodeficiency virus (HIV)-infected adults, particularly those of black race, are at high-risk for end-stage renal disease (ESRD), but contributing factors are evolving. We hypothesized that improvements in HIV treatment have led to declines in risk of ESRD, particularly among HIV-infected blacks.

METHODS

Using data from the North American AIDS Cohort Collaboration for Research and Design from January 2000 to December 2009, we validated 286 incident ESRD cases using abstracted medical evidence of dialysis (lasting >6 months) or renal transplant. A total of 38 354 HIV-infected adults aged 18-80 years contributed 159 825 person-years (PYs). Age- and sex-standardized incidence ratios (SIRs) were estimated by race. Poisson regression was used to identify predictors of ESRD.

RESULTS

HIV-infected ESRD cases were more likely to be of black race, have diabetes mellitus or hypertension, inject drugs, and/or have a prior AIDS-defining illness. The overall SIR was 3.2 (95% confidence interval [CI], 2.8-3.6) but was significantly higher among black patients (4.5 [95% CI, 3.9-5.2]). ESRD incidence declined from 532 to 303 per 100 000 PYs and 138 to 34 per 100 000 PYs over the time period for blacks and nonblacks, respectively, coincident with notable increases in both the prevalence of viral suppression and the prevalence of ESRD risk factors including diabetes mellitus, hypertension, and hepatitis C virus coinfection.

CONCLUSIONS

The risk of ESRD remains high among HIV-infected individuals in care but is declining with improvements in virologic suppression. HIV-infected black persons continue to comprise the majority of cases, as a result of higher viral loads, comorbidities, and genetic susceptibility.