The HIV-associated renal diseases: current insight into pathogenesis and treatment

A Systematic Review Exploring the Range of Renal Complications of Human Immunodeficiency Virus

Human immunodeficiency virus (HIV) is a viral infection which progressively leads to acquired immunodeficiency syndrome (AIDS) in the absence of treatment. This happens through the destruction of crucial cells in the immune system, such as the helper T cells, dendritic cells, and macrophages. Since the first case was isolated in the 20th century, the disease has spread rapidly among humans, with significant renal, cardiovascular, respiratory, and neurological complications. It is predominantly sexually transmitted but non-sexual transmission. A relationship between HIV and renal diseases has been suggested for a long time, but only a few systematic studies have centered on this association. This systematic review aims to analyze the possible association between HIV and renal diseases as well as the range and pathogenesis of these renal diseases. HIV remains a critical infectious disease globally, inciting substantial morbidity and mortality. Studies have shown that people living with HIV (PLWH) are at increased risk of acute and chronic kidney disease. This review is based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, Google Scholar, and Cochrane databases were searched exhaustively using the inclusion criteria of free full-text English papers that have exclusively studied humans in the last 20 years. Sixteen articles were selected including a systematic review, observational studies, and comprehensive narrative reviews on the role of HIV in the etiology of renal diseases, and were systemically reviewed and analyzed to elicit the wide range of possible renal complications resulting from HIV infection.

Clinicopathological correlation of kidney disease in HIV infection pre- and post-ART rollout

The spectrum of HIV-associated kidney disease has expanded significantly with the introduction of antiretroviral therapy (ART). In the pre-ART era there was prominence of HIV-associated nephropathy (HIVAN). More recently, the spectrum of disease additionally reflects comorbid illness in the ageing HIV population and ART-related nephrotoxicity. We performed a clinicopathological correlation of kidney disease in HIV-positive individuals who underwent kidney biopsy between 1989 and 2014, utilizing the 2018 Kidney Disease Improving Global Outcomes pathologic classification. ART rollout began in 2004 in South Africa. Patients biopsied pre-ART rollout were compared to those biopsied post-ART rollout with respect to demographics, clinical parameters and histology. We assessed kidney survival in a cohort of these patients following biopsy. Six hundred and ninety biopsies were included, 99 (14.3%) were undertaken pre- and 591 (85.7%) post-ART rollout. Most patients were of Black African descent (97.5%). The post-ART rollout patients were older (p = 0.007), had higher eGFR at presentation (p = 0.016) and fewer presented with eGFR of less than 15ml/min/1.73m2 (p = 0.0008). There was a decrease in the prevalence of classic HIVAN (p = 0.00001); and an increase in FSGS (NOS) in the setting of HIV (p = 0.0022) and tubulointerstitial diseases (p = 0.009) post-ART rollout. Kidney function survival over 5 years was poorest in patients with classic HIVAN (p = 0.00005) and best in minimal change nephropathy (p = 0.0013). Kidney biopsy is crucial for the correct diagnosis and management of HIV-related kidney disease. ART rollout has shifted the spectrum of kidney disease away from classic HIVAN but has not eliminated it. Histological diagnosis prognosticates kidney survival.

Prevalence and Pattern of Human Immunodeficiency Virus-Associated Nephropathy among Human Immunodeficiency Virus-Positive Children at the University of Maiduguri Teaching Hospital, Nigeria

The kidney is an important target organ in human immunodeficiency virus (HIV) infection, and a variety of renal disorders could occur throughout the course of the disease. HIV- associated nephropathy (HIVAN) is the most common form of kidney disease resulting directly from HIV infection. The true prevalence of HIVAN among infected African children is unknown largely due to lack of surveillance and reporting. We thus aimed to determine the prevalence of HIVAN and associated factors among HIV-infected children at the University of Maiduguri Teaching Hospital. This was a cross-sectional study carried out at the Pediatric Infectious Clinic. Children aged ≤15 years were recruited through systematic random sampling. Relevant sociodemographic and clinical information were obtained. Spot urine sample was analyzed using a multistix (Combi-Screen 10SL Analyticon Biotechnologies AG, Germany), and proteinuria of ≥2+ was considered significant. The CD4+ count and CD4+% (for those <5 years) were obtained using a PARTEC™ CD4+ easy count kit. The obtained data were entered and analyzed using Statistical Package for the Social Sciences version 16.0. A total of 250 children were recruited. Eighty-five (34%) of them had HIVAN. Sex, social class, and mode of transmission were not significantly associated with HIVAN (P >0.05). However, age, medication status (highly active antiretroviral therapy [HAART]), duration on HAART, and disease severity (both clinical and immunological) all had a significant association to HIVAN (p = 0.005, 0.004, 0.008, and <0.001, respectively). These factors also showed a positive but weak correlation to HIVAN; while age had the least correlation coefficient (0.157), immunological class had the highest r = 0.458. However, these relationships were all significant (P <0.5). HIVAN is highly prevalent among children living with HIV in Maiduguri. Routine screening through urina-lysis and early commencement of HAART is recommended.

HIV-associated Immune Complex Kidney Disease with C3-dominant Deposition Induced by HIV Infection after Treatment of IgA Nephropathy

A 57-year-old man was diagnosed with IgA nephropathy. Hematuria and proteinuria were improved by tonsillectomy plus methylprednisolone pulse therapy. Lymphadenopathy, hypocomplementemia and pancytopenia were observed six years later, and urinalysis abnormalities recurred. A biopsy revealed mesangial proliferative glomerulonephritis with C3-dominant deposition. Human immunodeficiency virus (HIV) antibody demonstrated positive conversion. He was diagnosed with HIV-associated immune complex kidney disease (HIVICK). The hematuria, proteinuria and hypocomplementemia were improved by reducing the HIV viral load through antiretroviral therapy. When C3-dominant deposition is observed on a renal biopsy, HIVICK must be differentiated.

A cross-sectional study on renal involvement among HIV-infected patients attending a tertiary care hospital in Kolkata

Background and objectives

The HIV-associated renal diseases represent a spectrum. Indian data on this is sparse. This study was undertaken to find out the prevalence and clinicopathological spectrum of renal involvement in HIV among antiretroviral therapy (ART) naïve patients (Group 1) and among those on ART (Group 2).

Methods

Systematic random sampling was undertaken to select 109 patients each from virology outpatient department (VOPD) and ART centre of a tertiary care hospital. They were screened and further investigated if renal involvement was found.

Results

Renal involvement was present in 25/109 (22.94%) and 15/109 (13.76%) patients of Groups 1 and 2, respectively. Among patients of Groups 1 and 2, 9/24 (37.5%) and 2/13 (15.4%), respectively, had clinically significant proteinuria, but none in the nephrotic range. Statistically significant relationships of renal involvement were observed with CD4 count <100/μl and with low BMI. Of the patients of Group 2, 20% of those on a tenofovir-based regimen had renal involvement with tubular changes, while only 4.6% of those on other regimens had renal involvement. This difference was statistically significant (p<0.05; OR=5.25).

Conclusion

Renal involvement was less common among those on ART. Low CD4 count and body mass index (BMI) were associated with renal dysfunction. Patients on a tenofovir-based regimen had more renal involvement compared with not on a tenofovir-based regimen.

Effects of Highly Active Antiretroviral Therapy on Renal Function and Renal Phosphate Handling in African Adults with Advanced HIV and CKD

BACKGROUND

Highly Active Antiretroviral Therapy (HAART) has been implicated in renal dysfunction with hypophosphataemia.

OBJECTIVE

We prospectively evaluated renal phosphate excretion during HAART use.

METHOD

Newly diagnosed human immunodeficiency virus (HIV)-infected individuals were treated with Tenofovir disoproxil fumarate/Emtricitabine/Efavirenz (TDF/FTC/EFV), n=33; Zidovudine/Lamivudine/Nevirapine (ZDV/3TC/NVP), n=53; and Zidovudine/Lamivudine/Efavirenz (ZDV/3TC/EFV), n=16. Creatinine and phosphate were assayed in blood and urine simultaneously at baseline, 1, 3, 6 and 9 months. Glomerular filtration rate (eGFR), fractional phosphate excretion and reabsorption (FEPi % and TRP), and the ratio of tubular maximum reabsorption of phosphate (TmP) to GFR (TmP/GFR) were estimated.

RESULTS

At baseline, eGFR showed moderate chronic kidney disease (mean: 35.50 ± 2.02, 33.14 ± 1.63, and 39.97±1.84 ml/min/1.73m2 in the 3 groups respectively); 54 (52.9%) patients had hyperphosphataemia (>1.4mmo/L); 43 (42.2%) had normophosphataemia (0.6-1.4mmol/L); 5 (4.9%) had hypophosphataemia (<0.6mmol/L). eGFR improved significantly from 1 month (≥60, 58.65 ± 1.11, and 51.76 ±1.59 ml/min/1.73m2; p=0.04, <0.001, 0.67 respectively), with a relapse at 9 months in TDFtreated subjects (50.10 ± 1.89 ml/min/1.73m2). TDF/FTC/EFV resulted in significantly greater reduction in plasma phosphate than ZDV/3TC/NVP (p=0.031), but not significantly different from ZDV/3TC/EFV (p=0.968). Similarly, ZDV/3TC/EFV resulted in significantly greater reduction in plasma phosphate than ZDV/3TC/NVP (p=0.036). FEP% progressively increased with HAART duration, more in TDF-treated and ZDV/3TC/EFV-treated groups than ZDV/3TC/NVP (p=0.014); TRP was elevated (>0.86), implying non-maximal phosphate reabsorption. TmP/GFR values were elevated, (>1.35mmol/l).

CONCLUSION

HIV causes kidney dysfunction with reduced phosphate excretion resulting in hyperphosphataemia but HAART improves renal function. Prolonged use of TDF can cause renal toxicity with hypophosphataemia as fractional excretion progressively increased with duration of therapy unlike ZDV/3TC/NVP. The use of different third agents (either NVP or EFV) in zidovudine-based therapy results in significantly different plasma phosphate levels; ZDV/3TC/EFV, like TDF/FTC/EFV, resulted in significantly greater decline in plasma phosphate than ZDV/3TC/NVP. Thus, Evafirenz (EVF) may have similar or synergistic adverse effects with tenofovir disoproxil fumarate (TDF).

The effects of add-on corticosteroids on renal outcomes in patients with biopsy proven HIV associated nephropathy: a single centre study from South Africa

BACKGROUND

The aim of this study was to assess, the efficacy and safety of add-on corticosteroids to antiretroviral therapy [ART] in patients with biopsy proven HIV associated nephropathy.

METHODS

All included patients had histological evidence of either collapsing or non-collapsing focal segmental glomerulosclerosis (FSGS) or podocyte and/or parietal cell hypertrophy or hyperplasia. All patients had evidence of tubulointerstitial inflammation with microcysts. Patients were randomized to ART with the addition of 1 mg/kg of corticosteroids [ART+C] or remained in the group [ART Alone] and followed for 2 years. A repeat biopsy was performed at 6 months.

RESULTS

Twenty-one patients were randomized to [ART+C] and 17 to [ART Alone]. The baseline estimated glomerular filtration rate (eGFR) was significantly lower in the [ART+C] vs. [ART Alone] group [35mls/min/1.73m² vs. 47 mls/min/1.73m², p = 0.015]. The [ART+C] cohort had a statistically significant improvement in median (eGFR) from baseline to last follow up compared with [ART Alone] i.e. [Δ = 25mls/min (IQR: 15;51) vs 9 mls/min (IQR: 0-24), p = 0.008]. There were no statistically significant differences between the groups when proteinuria and histology were analyzed. There were 8 deaths during the trial period, 7 from [ART+C] (Log rank p = 0.071).

CONCLUSIONS

In the [ART+C] cohort there was a significant improvement in eGFR over 2-years with increased mortality. Routine corticosteroid use cannot currently be recommended. Further investigation to define which subgroup of this cohort would safely benefit from the positive effects is required.

TRIAL REGISTRATION

ISRCTN study ID ( 56112439 ] was retrospectively registered on the 5 September 2018.

Membranous Nephropathy in a Patient with Human Immunodeficiency Virus Shortly After Initiation of HAART with Atripla

A human immunodeficiency virus (HIV) infection has long been associated with kidney disease. The pathogenesis of renal complications may be directly related to the presence of HIV viral particles or may occur secondary to an immune response against the virus. A number of HIV medications have been associated with the development of acute and chronic kidney disease. It has been estimated that approximately 60 percent of patients suffering from HIV/acquired immunodeficiency syndrome (AIDS) will, at some point, manifest clinically significant renal sequelae.The most common kidney disease affecting HIV patients is HIV-associated nephropathy (HIVAN) or focal segmental glomerulonephritis (FSGS). A very small subset of patients suffering from HIV/AIDS does go on to develop membranous glomerulonephritis. We present a case of a 55-year old Caucasian male who presented to the hospital after two weeks of weakness and falling when attempting to stand. The patient had a history of HIV, diagnosed in 1996. The latest cluster differentiation 4 (CD4) count was 245 cells/uL and the HIV-ribonucleic acid (RNA) viral load was reported as less than 75 copies/ml. The physical exam at presentation was insignificant. The laboratory examination revealed elevated creatinine. Potential nephrotoxic home medications, including Atripla and lisinopril, were held. After a brief inpatient stay, he was discharged but was ultimately readmitted for worsening renal function and nephrotic syndrome was diagnosed. Renal biopsy was performed, and membranous glomerulonephritis was confirmed. To this point, there are no associated cases reported of membranous glomerulonephritis after initiation of therapy with Atripla.

We present a case of a rare etiology of membranous nephropathy in an HIV patient. Physicians should be judicious in detecting the etiology of renal dysfunction in HIV patients.

The Role of Glucocorticoid Receptors in Podocytes and Nephrotic Syndrome

Glucocorticoid receptor (GC), a founding member of the nuclear hormone receptor superfamily, is a glucocorticoid-activated transcription factor that regulates gene expression and controls the development and homeostasis of human podocytes. Synthetic glucocorticoids are the standard treatment regimens for proteinuria (protein in the urine) and nephrotic syndrome (NS) caused by kidney diseases. These include minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), membranous nephropathy (MN) and immunoglobulin A nephropathy (IgAN) or subsequent complications due to diabetes mellitus or HIV infection. However, unwanted side effects and steroid-resistance remain major issues for their long-term use. Furthermore, the mechanism by which glucocorticoids elicit their renoprotective activity in podocyte and glomeruli is poorly understood. Podocytes are highly differentiated epithelial cells that contribute to the integrity of kidney glomerular filtration barrier. Injury or loss of podocytes leads to proteinuria and nephrotic syndrome. Recent studies in multiple experimental models have begun to explore the mechanism of GC action in podocytes. This review will discuss progress in our understanding of the role of glucocorticoid receptor and glucocorticoids in podocyte physiology and their renoprotective activity in nephrotic syndrome.

Long-Term Durability of Tenofovir-Based Antiretroviral Therapy in Relation to the Co-Administration of Other Drug Classes in Routine Clinical Practice

Background

In clinical trials, toxicity leading to tenofovir disoproxil fumarate (TDF) discontinuation is rare (3% by 2 years); however in clinical practice it seems to be higher, particularly when TDF is co-administered with ritonavir-boosted protease inhibitors (PI/r). Aims of this study were to assess the rate of TDF discontinuations in clinical practice and to identify factors associated with the risk of stopping TDF.

Methods

All antiretroviral treatment (ART)-naive patients initiating a TDF-based regimen were selected from the ICONA Foundation Study cohort. The primary outcome was TDF discontinuation regardless of the reason; secondary outcome measures were TDF discontinuation due to toxicity and selective TDF discontinuation (that is, TDF discontinuation or substitution, maintaining unchanged the remaining antiretroviral treatment).

Results

3,618 ART-naïve patients were included: 54% started a PI/r-based and 46% a NNRTI-based based regimen. Two-hundred-seventy-seven patients discontinued TDF and reintroduced ART within 30 days without TDF. The probability of TDF discontinuation regardless of the reason was of 7.4% (95%CI:6.4–8.5) by 2 years and 14.1% (95%CI:12.2–16.1) by 5 years. The 5-year KM estimates in the PI/r vs. NNRTI group were 20.4% vs. 7.6%, respectively (log-rank p = 0.0001), for the outcome of stopping regardless of the reason, and 10.7% vs. 4.7% (p = 0.0001) for discontinuation due to toxicity. PI/r use and lower eGFR were associated with an increased risk of discontinuing TDF.

Conclusion

In our cohort, the frequency of TDF discontinuations was higher than that observed in clinical trials. Co-administration of TDF with PI/r was associated with an increased rate of TDF discontinuations. Further studies are needed to clarify the mechanisms that might have led to this outcome.

Update on current management of chronic kidney disease in patients with HIV infection

The prevalence of HIV-associated chronic kidney disease (CKD) varies geographically and depends on the definition of CKD used, ranging from 4.7% to 38% globally. The incidence, however, has decreased with the use of effective combined antiretroviral therapy (cART). A wide variety of histological patterns are seen in HIV-associated kidney diseases that include glomerular and tubulointerstitial pathology. In resource-rich settings, there has been a plateau in the incidence of end-stage renal disease secondary to HIV-associated nephropathy (HIVAN). However, the prevalence of end-stage renal disease in HIV-positive individuals has risen, mainly due to increased longevity on cART. There is a disparity in the occurrence of HIVAN among HIV-positive individuals such that there is an 18- to 50-fold increased risk of developing kidney disease among HIV-positive individuals of African descent aged between 20 and 64 years and who have a poorer prognosis compared with their European descent counterparts, suggesting that genetic factors play a vital role. Other risk factors include male sex, low CD4 counts, and high viral load. Improvement in renal function has been observed after initiation of cART in patients with HIV-associated CKD. Treatment with an angiotensin-converting enzyme inhibitor/angiotensin receptor blocker is recommended, when clinically indicated in patients with confirmed or suspected HIVAN or clinically significant albuminuria. Other standard management approaches for patients with CKD are recommended. These include addressing other cardiovascular risk factors (appropriate use of statins and aspirin, weight loss, cessation of smoking), avoidance of nephrotoxins, and management of serum bicarbonate and uric acid, anemia, calcium, and phosphate abnormalities. Early diagnosis of kidney disease by screening of HIV-positive individuals for the presence of kidney disease is critical for the optimal management of these patients. Screening for the presence of kidney disease upon detection of HIV infection and annually thereafter in high-risk populations is recommended.

Systolic blood pressure, routine kidney variables and renal ultrasonographic findings in cats naturally infected with feline immunodeficiency virus

Objectives Hypertension is a common cause of proteinuria in HIV-infected people. In cats, feline immunodeficiency virus (FIV) infection appears to be associated with proteinuria. Therefore, the results from systolic blood pressure (SBP) measurements in naturally infected FIV-positive cats were reviewed to assess whether hypertension contributes to the observed proteinuria in these cats. Ultrasonographic findings in FIV-positive cats were reviewed to complete renal assessment and to extend the scant knowledge on renal ultrasonography in cats. Methods Data from client-owned, naturally infected FIV-positive cats were retrospectively reviewed. To obtain a control group, records were reviewed from age-matched, privately owned, FIV-negative cats. Results Data from 91 FIV-infected and 113 control cats were compared. FIV-infected cats showed a significantly lower SBP ( P <0.0001) and significantly fewer FIV-infected cats were hypertensive (⩾160 mmHg) compared with control cats ( P = 0.025). The prevalence of renal azotaemia did not significantly differ between groups, although FIV-infected cats had significantly lower urine specific gravity (USG) ( P = 0.0273) and a higher incidence of USG below 1.035 ( P = 0.043). Urinary protein:creatinine ratio (UPC) was significantly higher in FIV-infected cats ( P = 0.0005) and proteinuria (UPC >0.4) occurred more frequently in FIV-infected cats ( P <0.001). Renal ultrasonography showed abnormalities in 60/91 FIV-infected cats, with hyperechogenic cortices in 39/91 and enlarged kidneys in 31/91. Conclusions and relevance Hypertension can be excluded as a common cause of renal damage leading to proteinuria in FIV-infected cats. Proteinuria and poorly concentrated urine are common in naturally infected FIV-positive cats, in contrast to azotaemia. Clinicians should cautiously interpret ultrasonographic abnormalities as these occur in over half of FIV-infected cats.

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.

Saquinavir Loaded Acetalated Dextran Microconfetti - a Long Acting Protease Inhibitor Injectable

PURPOSE

Since the adoption of highly active antiretroviral therapy, HIV disease progression has slowed across the world; however, patients are often required to take multiple medications daily of poorly bioavailable drugs via the oral route, leading to gastrointestinal irritation. Recently, long acting antiretroviral injectables that deliver drug for months at a time have moved into late phase clinical trials. Unfortunately, these solid phase crystal formulations have inherent drawbacks in potential dose dumping and a greater likelihood for burst release of drug compared to polymeric formulations.

METHODS

Using electrospinning, acetalated dextran scaffolds containing the protease inhibitor saquinavir were created. Grinding techniques were then used to process these scaffolds into injectables which are termed saquinavir microconfetti. Microconfetti was analyzed for in vitro and in vivo release kinetics.

RESULTS

Highly saquinavir loaded acetalated dextran electrospun fibers were able to be formed and processed into saquinavir microconfetti while other polymers such as poly lactic-co-glycolic acid and polycaprolactone were unable to do so. Saquinavir microconfetti release kinetics were able to be tuned via drug loading and polymer degradation rates. In vivo, a single subcutaneous injection of saquinavir microconfetti released drug for greater than a week with large tissue retention.

CONCLUSIONS

Microconfetti is a uniquely tunable long acting injectable that would reduce the formation of adherence related HIV resistance. Our findings suggest that the injectable microconfetti delivery system could be used for long acting controlled release of saquinavir and other hydrophobic small molecule drugs.

Microalbuminuria among HIV-infected antiretroviral therapy-naive children in the Democratic Republic of Congo

BACKGROUND

To determine the prevalence of microalbuminuria and associated factors among Congolese human immunodeficiency virus (HIV)-infected children.

METHODS

This was a cross-sectional study in which 77 HIV-infected antiretroviral therapy-naive children and 89 uninfected controls were enrolled. Microalbuminuria was assessed using the immune-turbidimetry method, and associated factors were studied by logistic regression.

RESULTS/CONCLUSION

The prevalence of microalbuminuria was 18% in the HIV-infected children and 2% in the HIV-uninfected children. No common determinants of proteinuria were significantly associated with microalbuminuria.

HIV-associated immune complex kidney disease

The introduction in the late 20(th) century of combination antiretroviral therapy (cART) to treat patients infected with HIV has changed the natural history of the disease from an acute illness that rapidly culminates in death, to a chronic condition that can be managed with medications. Over the past decade the epidemiology of kidney disease in US patients infected with HIV has changed, perhaps because of the increased availability and use of cART. Patients with HIV infection exhibit unique immunologic characteristics, including immunodeficiency and dysregulation of immunoglobulin synthetic responses and T-cell function, which can result in glomerular immune complex deposition and subsequent kidney injury. This Review examines the differential diagnoses of HIV-associated immune complex kidney diseases (HIVICD), and discusses the clinical manifestations and mechanisms underlying their development. We address the issues associated with treatment, clinical outcomes, and research needs to enhance our ability to diagnose and optimally treat patients with HIVICD.

Prevalence and Pattern of Chronic Kidney Disease in Antiretroviral-Naïve Patients with HIV/AIDS

BACKGROUND

Chronic renal failure and HIV/AIDS are both prevalent in Nigeria. We performed a cross-sectional analysis of renal function in newly diagnosed, treatment-naive HIV-infected patients before initiating highly active antiretroviral therapy.

METHODS

Treatment-inexperienced individuals were recruited. Patients with diabetes mellitus and hypertension were excluded. Plasma creatinine level was used to measure the estimated glomerular filtration rate ([eGFR] by Modification of Diet in Renal Disease equation). Predictors of creatinine and eGFR were determined by univariate and multivariate analyses.

RESULTS

We evaluated 183 patients. In all, 44 (24%) patients had a GFR <60 mL/min/1.73 m(2), implying moderate chronic kidney disease (CKD). Considering the eGFR, 22 (12%) patients had stage 1, 117 (63.9%) stage 2, 13 (7.1%) stage 3, 27 (14.8%) stage 4, and 4 (2.2%) stage 5 CKD. Creatinine inversely correlated with CD4 (r = -.228, P = .025). CD4 predicts creatinine (odds ratio 1.6, 95% confidence interval 1.0-1.8, P = .003).

CONCLUSION

In ART-naive patients, CKD is common, and low eGFR was associated with lower CD4 counts.

Clinical remission of IgA nephropathy in an HIV-positive patient after combined treatment with tonsillectomy and steroid pulse therapy

Various renal diseases other than human immunodeficiency virus (HIV)-associated nephropathy, including IgA nephropathy (IgAN), have been recently reported to cause chronic kidney disease and end-stage renal disease in HIV-infected patients. The case of a 37-year-old HIV-infected male diagnosed as having IgAN with proteinuria and microscopic hematuria that was successfully treated with tonsillectomy and steroid pulse therapy in combination, resulting in disappearance of urinary abnormalities (clinical remission), is reported, the first such case in the literature. A renal biopsy revealed mesangial proliferation associated with mesangial deposition of IgA and C3, consistent with IgAN. Antiretroviral therapy and angiotensin receptor blocker therapy did not improve his proteinuria. Therefore, he underwent tonsillectomy and steroid pulse therapy, and clinical remission was successfully achieved with no opportunistic infections. Clinical remission has continued for more than 3 years even after discontinuation of steroid therapy. It appears that combined treatment with tonsillectomy and steroid pulse therapy can be a good choice in managing HIV-infected patients with IgAN as long as secondary infection is strictly and continuously monitored.

Baseline Renal Function among Antiretroviral Therapy-Naive, HIV-Infected Patients in Southeast Nigeria

Background:

Renal insufficiency has been shown to be a significant, independent risk factor for mortality among HIV-infected patients. Unfortunately, little is known about the prevalence and nature of renal impairment in African populations initiating antiretroviral treatment. This study aims to find the prevalence of abnormal renal function among antiretroviral therapy (ART)-naive, HIV-infected patients in the South Eastern geopolitical zone of Nigeria.

Method:

This is a cross-sectional hospital-based study, involving 300 ART-naive HIV-positive patients, seen over a 1-year period, aged from 18 years and older, presenting to the clinic for the first time.

Results:

A total of 300 patients were included in the study, 104 (34.7%) males and 196 (65.3%) females. The prevalence of significant renal disease was 24.3% (73 of 300), while 38.3% (115 of 300) had mild renal impairment. Using logistic regression, age, CD4 count, urea, creatinine, and hemoglobin were significantly associated with renal impairment.

Conclusion:

The authors observed a high prevalence of significant renal impairment among HIV-infected patients at the time of ART initiation.

Kidney disease in children and adolescents with perinatal HIV-1 infection

Introduction

Involvement of the kidney in children and adolescents with perinatal (HIV-1) infection can occur at any stage during the child's life with diverse diagnoses, ranging from acute kidney injury, childhood urinary tract infections (UTIs), electrolyte imbalances and drug-induced nephrotoxicity, to diseases of the glomerulus. The latter include various immune-mediated chronic kidney diseases (CKD) and HIV-associated nephropathy (HIVAN).

Discussion

The introduction of highly active anti-retroviral therapy (HAART) has dramatically reduced the incidence of HIVAN, once the commonest form of CKD in children of African descent living with HIV, and also altered its prognosis from eventual progression to end-stage kidney disease to one that is compatible with long-term survival. The impact of HAART on the outcome of other forms of kidney diseases seen in this population has not been as impressive. Increasingly important is nephrotoxicity secondary to the prolonged use of anti-retroviral agents, and the occurrence of co-morbid kidney disease unrelated to HIV infection or its treatment. Improved understanding of the molecular pathogenesis and genetics of kidney diseases associated with HIV will result in better screening, prevention and treatment efforts, as HIV specialists and nephrologists coordinate clinical care of these patients. Both haemodialysis (HD) and peritoneal dialysis (PD) are effective as renal replacement therapy in HIV-infected patients with end-stage kidney disease, with PD being preferred in resource-limited settings. Kidney transplantation, once contraindicated in this population, has now become the most effective renal replacement therapy, provided rigorous criteria are met. Given the attendant morbidity and mortality in HIV-infected children and adolescents with kidney disease, routine screening for kidney disease is recommended where resources permit.

Conclusions

This review focuses on the pathogenesis and genetics, clinical presentation and management of kidney disease in children and adolescents with perinatal HIV-1 infection.

Baseline Renal Function among Antiretroviral Therapy-Naive, HIV-Infected Patients in South East Nigeria

Background:Renal insufficiency has been shown to be a significant, independent risk factor for mortality among HIV-infected patients. Unfortunately, little is known about the prevalence and nature of renal impairment in African populations initiating antiretroviral treatment. This study aims to find the prevalence of abnormal renal function among antiretroviral therapy (ART)-naive, HIV-infected patients in the South Eastern geopolitical zone of Nigeria.Method:This is a cross-sectional hospital-based study, involving 300 ART-naive HIV-positive patients, seen over a 1-year period, aged from 18 years and older, presenting to the clinic for the first time.Results:A total of 300 patients were included in the study, 104 (34.7%) males and 196 (65.3%) females. The prevalence of significant renal disease was 24.3% (73 of 300), while 38.3% (115 of 300) had mild renal impairment. Using logistic regression, age, CD4 count, urea, creatinine, and hemoglobin were significantly associated with renal impairment.Conclusion:The authors observed a high prevalence of significant renal impairment among HIV-infected patients at the time of ART initiation.

Routine health screening: findings in apparently healthy middle-aged and old cats

STUDY RATIONALE

Veterinary practitioners often perform geriatric health screening in cats. Unfortunately, scientific information regarding clinical and laboratory abnormalities and normal blood pressure values in elderly cats is scarce. This prospective study evaluated routine health screening tests in apparently healthy middle-aged and old cats.

PROTOCOL

One hundred cats of 6 years and older underwent blood pressure measurement, physical examination, blood and urine analysis, indirect fundoscopy and bilateral Schirmer tear tests.

FINDINGS

Mean systolic blood pressure (SBP) was 133.6 ± 21.5 mmHg. Increased SBP (>160 mmHg) was observed in eight cats, submandibular lymphadenopathy in 32, gingivitis in 72, heart murmur in 11, thyroid goitre in 20, increased creatinine in 29, hyperglycaemia in 25, increased total thyroxine in three, feline immunodeficiency virus positivity in 14, crystalluria in 41, borderline proteinuria in 25 and overt proteinuria in two. Mean tear production was very similar for both eyes and none of the cats had ocular lesions secondary to hypertension.

CLINICAL SIGNIFICANCE

Old cats (>10 years) had significantly higher SBP, heart rate, murmur frequency, thrombocyte count, urine protein:creatinine ratio and serum urea and bilirubin concentrations, and significantly lower body condition score, haematocrit, albumin and total calcium concentrations than middle-aged cats (6-10 years). The common occurrence of physical examination and laboratory abnormalities in apparently healthy old cats underlines the need for regular health checks and the development of age-dependent laboratory reference intervals.

Renal AA-amyloidosis in intravenous drug users--a role for HIV-infection?

Background

Chronic renal disease is a serious complication of long-term intravenous drug use (IVDU). Recent reports have postulated a changing pattern of underlying nephropathy over the last decades.

Methods

Retrospective investigation including all patients with prior or present IVDU that underwent renal biopsy because of chronic kidney disease between 01.04.2002 and 31.03.2012 in the city of Frankfurt/Main, Germany.

Results

Twenty four patients with IVDU underwent renal biopsy because of progressive chronic kidney disease or proteinuria. Renal AA-amyloidosis was the predominant cause of renal failure in 50% of patients. Membranoproliferative glomerulonephritis (GN) was the second most common cause found in 21%. Patients with AA-amyloidosis were more likely to be HIV infected (67 vs.17%; p=0.036) and tended to have a higher rate of repeated systemic infections (92 vs. 50%; p=0.069). Patients with AA-amyloidosis presented with progressive renal disease and nephrotic-range proteinuria but most patients had no peripheral edema or systemic hypertension. Development of proteinuria preceded the decline of GFR for approximately 1–2 years.

Conclusions

AA-amyloidosis was the predominant cause of progressive renal disease in the last 10 years in patients with IVDU. The highest rate of AA-amyloidosis observed was seen in HIV infected patients with IVDU. We speculate that chronic HIV-infection as well as the associated immunosuppression might promote development of AA-amyloidosis by increasing frequency and duration of infections acquired by IVDU.

The spectrum of HIV-related nephropathy in children

BACKGROUND

Despite the burden of human immunodeficiency virus (HIV) disease in Southern Africa, there have been few reports of HIV-related nephropathy in children. This study outlines the spectrum of HIV-1-related kidney diseases of children in KwaZulu-Natal, South Africa.

METHODS

A review of the clinical presentation, laboratory and histopathological findings of children diagnosed with HIV-related nephropathy.

RESULTS

Forty-nine out of 71 children (1-16 years old) with HIV-1 related nephropathy underwent kidney biopsy. The most common histopathological finding was focal segmental glomerulosclerosis (FSGS), which was present in 32 (65.3%) children; 13 (26.5%) having collapsing glomerulopathy and 19 (38.8%) classic FSGS. The majority of patients showed haematological (86.4%) and electrolyte abnormalities (69.4%). Renal impairment was present in 41% of patients on initial presentation. However, end-stage kidney disease was present in only 4% of these patients. All patients were treated with highly active anti-retroviral therapy (HAART), the majority (79.6%) showed decreased proteinuria with 38.8% having complete remission.

CONCLUSIONS

This study, one of the largest series of children reported from Africa, demonstrates that nephrotic syndrome due to HIV-associated nephropathy (HIVAN) is the commonest presentation of HIV-related nephropathy in childhood. Highly active anti-retroviral therapy in combination with angiotensin-converting enzyme antagonists is highly effective in decreasing proteinuria and preserving renal function.

Profiling of autoantibodies in IgA nephropathy, an integrative antibiomics approach

BACKGROUND AND OBJECTIVES

IgG commonly co-exists with IgA in the glomerular mesangium of patients with IgA nephropathy (IgAN) with unclear clinical relevance. Autoantibody (autoAb) biomarkers to detect and track progression of IgAN are an unmet clinical need. The objective of the study was to identify IgA-specific autoAbs specific to IgAN.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

High-density protein microarrays were evaluated IgG autoAbs in the serum of IgAN patients (n = 22) and controls (n = 10). Clinical parameters, including annual GFR and urine protein measurements, were collected on all patients over 5 years. Bioinformatic data analysis was performed to select targets for further validation by immunohistochemistry (IHC).

RESULTS

One hundred seventeen (1.4%) specific antibodies were increased in IgAN. Among the most significant were the autoAb to the Ig family of proteins. IgAN-specific autoAbs (approximately 50%) were mounted against proteins predominantly expressed in glomeruli and tubules, and selected candidates were verified by IHC. Receiver operating characteristic analysis of our study demonstrated that IgG autoAb levels (matriline 2, ubiquitin-conjugating enzyme E2W, DEAD box protein, and protein kinase D1) might be used in combination with 24-hour proteinuria to improve prediction of the progression of IgAN (area under the curve = 0.86, P = 0.02).

CONCLUSIONS

IgAN is associated with elevated IgG autoAbs to multiple proteins in the kidney. This first analysis of the repertoire of autoAbs in IgAN identifies novel, immunogenic protein targets that are highly expressed in the kidney glomerulus and tubules that may bear relevance in the pathogenesis and progression of IgAN.

Feline immunodeficiency virus: disease association versus causation in domestic and nondomestic felids

Feline immunodeficiency virus (FIV) is an important infection in both domestic and nondomestic cats. Although many studies have provided insight into FIV pathophysiology and immunologic responses to infection in cats, questions remain regarding the association of FIV with specific disease syndromes. For many diseases, both association and causation of disease with FIV remain to be confirmed and clarified. The use of experimental infection models is unlikely to yield answers about naturally infected domestic cats and is not feasible in nondomestic felids, many of which are endangered species. Researches might consider further study of naturally occurring disease with an emphasis on confirming which diseases have a likely association with FIV.

Renal disease in HIV infected patients at University of Benin Teaching Hospital in Nigeria

BACKGROUND

HIV related renal disease is a common occurrence in patients with HIV infection. It is the third leading cause of end stage renal disease among African-American males between the ages of 20 and 64 years in USA. Renal function impairment has been reported at all stages of HIV infection. The aim of this study is to determine the relationship between severity of renal function impairment and CD4 cell count in HIV infected patients.

METHOD

HIV patients presenting at University of Benin Teaching Hospital Benin, City Nigeria from 1(st) January to 30(th) June 2007 were randomly selected and screened for renal functional impairment (RFI). Those with RFI detected by glomerular filtration rate < 60 ml/min/1.73 m(2) or urine protein creatinine ratio 3 200 were stratified into mild, moderate and severe RFI. Forty patients from each stratum and forty HIV infected patients with normal renal functions were recruited as subjects and control respectively. Their clinical and laboratory parameters were evaluated. The data obtained were analysed using SPSS vs 15.0.

RESULTS

Of the HIV patients screened, 53.3% had renal functional impairment. of these, 40.2% had mild, 37.7% had moderate and 22.2% had severe impairment in their renal functions respectively Their mean age was 36.0 ± 8.8 years. The CD4 cell count was found to be 309.75 ± 268.71/ul, 188.45 ± 173.12/ul, and 141.10 ± 126.01/ul among subjects with mild, moderate and severe RFI respectively. The CD4 cell count in control group was 319.05 ± 248.41/ul. The difference was statistically significant. (p = <0.001). CD4 cell count had a significant positive correlation with GFR (r = 0.32, p = 0.042). However, there was a negative correlation between CD4 cell count and proteinuria but this was not statistically significant (r = 0.09, p = 0.173).

CONCLUSION

Severity of RFI has a positive correlation with degree of immunosuppression in HIV infected patients.

The effect of dialysis chains on mortality among patients receiving hemodialysis

OBJECTIVE

To examine the association between dialysis facility chain affiliation and patient mortality.

STUDY SETTING

Medicare dialysis population.

STUDY DESIGN

Data from the United States Renal Data System (USRDS) were used to identify 3,601 free-standing dialysis facilities and 34,914 Medicare patients' incidence to end-stage renal disease (ESRD) in 2004. Mixed-effect regression models were used to estimate patient mortality by dialysis facility chain and profit status during the 2-year follow-up.

DATA COLLECTION

USRDS data were matched with facility, cost, and census data.

PRINCIPAL FINDINGS

Of the five largest dialysis chains, the lowest mortality risk was observed among patients dialyzed at nonprofit (NP) Chain 5 facilities. Compared with Chain 5, hazard ratios were 19 percent higher (95 percent CI 1.06-1.34) and 24 percent higher (95 percent CI 1.10-1.40) for patients dialyzed at for-profit (FP) Chain 1 and Chain 2 facilities, respectively. In addition, patients at FP facilities had a 13 percent higher risk of mortality than those in NP facilities (95 percent CI 1.06-1.22).

CONCLUSIONS

Large chain affiliation is an independent risk factor for ESRD mortality in the United States. Given the movement toward further consolidation of large FP chains, reasons behind the increase in mortality require scrutiny.

Spectrum of Clinical Presentations in Human Immunodeficiency Virus (HIV) Infected Patients with Renal Disease

HIV infection is a multiorgan disease with the kidney not spared. A variety of renal syndromes with varying clinical presentations has been reported amongst HIV infected patients. This study aims to highlight the spectrum of clinical presentations in HIV infected patients with renal disease. HIV infected patients presenting at University of Benin Teaching Hospital (UBTH) Benin City were the study population. A total of 383 patients were studied. Their biodata, clinical presentations and laboratory investigations including serum urea, creatinine and albumin, urine protein and creatinine were assessed. Their glomerular filtration rate (GFR) and protein urine excretion were calculated using six equations of modification of diet in renal disease (MDRD) and protein: creatinine ratio respectively. Patients were stratified according to their renal functions into normal, mild, moderate and severe renal function impairment. The data was analysed using statistical software program SPSS Vs 15.0. 53.3% of 383 patients screened had renal function impairment, 40.2% mild, 37.7% moderate and 22.2% severe impairment. Mean age was 35.6±8.3, 36.0±9.9 and 36.3±8.3 years for mild, moderate and severe renal function impairment (RFI) respectively. Easy fatigability was the commonest symptoms occurring in 47.5%, 30.0%, 37.5% and 22.5% of control, mild RFI, moderate RFI and severe RFI subjects respectively (p = 0.568). Oliguria, facial and body swelling occurred more in patients with RFI especially in patients with severe renal impairment. The difference is statistically significant (p = 0.046, 0.041, and 0.033 respectively). Pallor was the commonest clinical sign occurring in 32.5%, 50.0%, 35.0% and 62.5% of control and patients with mild, moderate, and severe RFI respectively; the difference was not statistically significant (p = 0.459). Ascites, facial puffiness and pedal oedema were commoner in patients with RFI especially those with severe RFI. The differences were statistically significant. (p = 0.048, 0.019, and 0.008 respectively). In conclusion spectrum of clinical presentations in HIV patients with renal impairment are many but few are specific to these patients.

Hypomagnesemia is a risk factor for nonrecovery of renal function and mortality in AIDS patients with acute kidney injury

The objective of the present study was to determine the prevalence of electrolyte disturbances in AIDS patients developing acute kidney injury in the hospital setting, as well as to determine whether such disturbances constitute a risk factor for nephrotoxic and ischemic injury. A prospective, observational cohort study was carried out. Hospitalized AIDS patients were evaluated for age; gender; coinfection with hepatitis; diabetes mellitus; hypertension; time since HIV seroconversion; CD4 count; HIV viral load; proteinuria; serum levels of creatinine, urea, sodium, potassium and magnesium; antiretroviral use; nephrotoxic drug use; sepsis; intensive care unit (ICU) admission, and the need for dialysis. Each of these characteristics was correlated with the development of acute kidney injury, with recovery of renal function and with survival. Fifty-four patients developed acute kidney injury: 72% were males, 59% had been HIV-infected for >5 years, 72% had CD4 counts <200 cells/mm(3), 87% developed electrolyte disturbances, 33% recovered renal function, and 56% survived. ICU admission, dialysis, sepsis and hypomagnesemia were all significantly associated with nonrecovery of renal function and with mortality. Nonrecovery of renal function was significantly associated with hypomagnesemia, as was mortality in the multivariate analysis. The risks for nonrecovery of renal function and for death were 6.94 and 6.92 times greater, respectively, for patients with hypomagnesemia. In hospitalized AIDS patients, hypomagnesemia is a risk factor for nonrecovery of renal function and for in-hospital mortality. To determine whether hypomagnesemia is a determinant or simply a marker of critical illness, further studies involving magnesium supplementation in AIDS patients are warranted.

Collapsing glomerulopathy in Portugal: a review of the histological and clinical findings in HIV and non-HIV patients

BACKGROUND

Collapsing glomerulopathy (CG) is a glomerulonephritis seen in association with human immunodeficiency virus (HIV) infection, known as HIV-associated nephropathy (HIVAN), and less frequently observed in non-HIV-infected patients. Method. The aim of this study was to review the histological and clinical findings of all CG diagnosed since 1981 in our laboratory. Result. Since 1981, 18 kidney biopsies with collapsing features were diagnosed among 6130 biopsies performed: 72.2% (n = 13) males, mean age 33.8 ± 9.7 years, 61.1% (n = 11) of black ethnic origin. HIV infection was present in 10 patients. Mean serum creatinine (Scr) was 4.7 ± 2.5 mg/dL, and mean proteinuria was 6.1 ± 5 g/24 h. Both HIVAN and non-HIVAN patients were similar in terms of age, gender and dialysis requirement. In the HIVAN population, African origin was predominant and more frequent than in the non-HIVAN population, Scr was higher and proteinuria was less severe. Interstitial infiltrate, interstitial fibrosis and tubular atrophy were severe, and the presence of microcystic dilatation of renal tubules was more common. Immunofluorescence was positive in six patients. In the non-HIVAN population, this histological lesion was related to an infectious illness in 6/8 patients and to the use of illegal oral drugs in one patient. Interstitial infiltrate, interstitial fibrosis and tubular atrophy presented as moderate to severe, and tubular atrophy correlated with dialysis requirement. Mesangial proliferation was present in 3/8 patients, with C3 and IgA deposits.

CONCLUSION

CG is a rare podocytopathy. In this study, the association between infection and CG is evident, and we may suggest that infections could, in a direct or indirect manner, be a trigger of podocyte injury.

Estimated glomerular filtration rate, chronic kidney disease and antiretroviral drug use in HIV-positive patients

OBJECTIVES

Chronic kidney disease (CKD) in HIV-positive persons might be caused by both HIV and traditional or non-HIV-related factors. Our objective was to investigate long-term exposure to specific antiretroviral drugs and CKD.

DESIGN

A cohort study including 6843 HIV-positive persons with at least three serum creatinine measurements and corresponding body weight measurements from 2004 onwards.

METHODS

CKD was defined as either confirmed (two measurements >or=3 months apart) estimated glomerular filtration rate (eGFR) of 60 ml/min per 1.73 m or below for persons with baseline eGFR of above 60 ml/min per 1.73 m or confirmed 25% decline in eGFR for persons with baseline eGFR of 60 ml/min per 1.73 m or less, using the Cockcroft-Gault formula. Poisson regression was used to determine factors associated with CKD.

RESULTS

Two hundred and twenty-five (3.3%) persons progressed to CKD during 21 482 person-years follow-up, an incidence of 1.05 per 100 person-years follow-up [95% confidence interval (CI) 0.91-1.18]; median follow-up was 3.7 years (interquartile range 2.8-5.7). After adjustment for traditional factors associated with CKD and other confounding variables, increasing cumulative exposure to tenofovir [incidence rate ratio (IRR) per year 1.16, 95% CI 1.06-1.25, P < 0.0001), indinavir (IRR 1.12, 95% CI 1.06-1.18, P < 0.0001), atazanavir (IRR 1.21, 95% CI 1.09-1.34, P = 0.0003) and lopinavir/r (IRR 1.08, 95% CI 1.01-1.16, P = 0.030) were associated with a significantly increased rate of CKD. Consistent results were observed in wide-ranging sensitivity analyses, although of marginal statistical significance for lopinavir/r. No other antiretroviral drugs were associated with increased incidence of CKD.

CONCLUSION

In this nonrandomized large cohort, increasing exposure to tenofovir was associated with a higher incidence of CKD, as was true for indinavir and atazanavir, whereas the results for lopinavir/r were less clear.

HIV and the Kidney

Direct effects of HIV-1 infection on the kidney combine with immune and genetic factors, comorbidities, coinfections, and medication toxicities to induce a spectrum of kidney disorders in HIV disease. The most dramatic of these, HIV-associated nephropathy (HIVAN), emerges almost exclusively in persons of African descent and is associated with rapid progression to end-stage renal disease in the absence of antiretroviral therapy (ART). ART modifies the natural history of HIVAN, but the renal benefits of ART may not be limited to HIVAN. ART is often under prescribed or incorrectly dosed in persons with kidney disease. Vigilant attention to renal function and an understanding of the complex associations involving the kidneys are necessary for optimal care of these patients.

[Diagnosis, treatment and prevention of renal diseases in HIV infected patients. Recommendations of the Spanish AIDS Study Group/National AIDS Plan]

The incidence of opportunistic infections and tumours in HIV-infected patients has sharply declined in the HAART era. At the same time there has been a growing increase of other diseases not directly linked to immunodeficiency. Renal diseases are an increasing cause of morbidity and mortality among HIV-infected patients. In the general population, chronic renal failure has considerable multiorgan repercussions that have particular implications in patients with HIV infection. The detection of occult or subclinical chronic kidney disease is crucial since effective measures for delaying progression exist. Furthermore, the deterioration in glomerular filtration should prompt clinicians to adjust doses of some antiretroviral agents and other drugs used for treating associated comorbidities. Suppression of viral replication, strict control of blood pressure, dyslipidemia and diabetes mellitus, and avoidance of nephrotoxic drugs in certain patients are fundamental components of programs aimed to prevent renal damage and delaying progression of chronic kidney disease in patients with HIV. Renal transplantation and dialysis have also special implications in HIV-infected patients. In this article, we summarise the updated clinical practice guidelines for the evaluation, management and prevention of renal diseases in HIV-infected patients from a panel of experts in HIV and nephrologists on behalf of the Spanish AIDS Study Group (GESIDA) and the National AIDS Plan.

CKD in HIV-infected patients other than HIV-associated nephropathy

A spectrum of kidney diseases in HIV-infected patients has been reported both before and after the introduction of highly active antiretroviral therapy (HAART). Kidney syndromes affecting HIV-infected patients include CKD as well as proteinuria, nephrotic syndrome, and acute nephritic syndrome. Thrombotic microangiopathy should be considered in patients with kidney disease and typical clinical characteristics. As the HIV-infected population ages, there is increased concern regarding the incidence of vascular and metabolic disease, leading to an increased burden of CKD. Although HIV-associated nephropathy is still the major cause of nephrotic syndrome in HIV-infected patients, immune complex glomerulonephritis (ICGN) still comprises a substantial proportion of the disease burden, especially in people of European origin. Genetic investigations into the underpinnings of the various histologic expressions of HIV-associated kidney disease hold great promise. The single most important diagnostic test to differentiate various forms of kidney disease in HIV-infected patients is a kidney biopsy. The results of treating kidney disease in HIV-infected patients remain unclear, and properly designed randomized controlled trials of the treatment of ICGN with HAART and other approaches are desperately needed.

[Kidney diseases in HIV-infected patients]

HIV infection has become a global disease, both in geographic terms, since it has spread worldwide, and at the individual level since it affects every organ of the human body. Antiretroviral treatments, in countries where they are easily available, have modified HIV infection into a systemic chronic disease, the life expectancy of which is yet to be determined precisely. Treatments have dramatically changed the pattern of the disease and clinicians now have to face a number of new challenges. Kidneys, like all the other organs, can be involved in a great number of diseases in HIV-infected patients. We have voluntarily chosen to present "kidney diseases in HIV-infected patients" in their wider meaning, with a discussion of renal diseases that are directly caused by the virus, nephropathies due to frequent viral co-infections in HIV-infected patients such as HCV and HBV, nephropathies induced by anti-HIV, HBV and HCV therapies. Physicians in charge of HIV-infected patients should be aware of the key role they have to play in the screening for kidney abnormalities. This participates not only in improving patients' kidney prognosis but also their long-term general outcome. Renal screening strategies must refer to simple routine laboratory tests. Enclosed at the end of this article are a few suggestions for the renal management of situations that frequently occur in HIV infected patients (kidney dysfunction screening, serum creatinine increase and discovery of a proteinuria).

Acute kidney injury in patients with human immunodeficiency virus infection

PURPOSE OF REVIEW

To present an overview of the epidemiology and etiology of acute kidney injury (AKI) in patients infected with human immunodeficiency virus (HIV).

RECENT FINDINGS

HIV-infected patients are at an increased risk of developing AKI. Potential risk factors for the development of AKI in this patient population include increased HIV viral loads, reduced CD4 cell counts, hepatitis C virus coinfection, a history of diabetes, black race, male gender, and baseline chronic kidney and hepatic disease. Observational studies have found an increased morbidity and mortality in HIV-infected patients who develop AKI. There are diverse etiologies of AKI in HIV-infected patients, with increasing reports of highly active antiretroviral therapy-related nephropathy secondary to tenofovir nephrotoxicity. There have also been recent case reports of HIV-infected patients who develop a unique form of acute interstitial nephritis secondary to diffuse infiltrative lymphocytosis syndrome.

SUMMARY

There are a variety of etiologies of AKI in HIV-infected patients. Prompt diagnosis and treatment of AKI is critical to help prevent morbidity and mortality in this patient population.

HIV-associated nephropathy in Caucasians: case report and review of literature

HIV-associated nephropathy (HIVAN) is almost exclusively seen in African-Americans (AA) and is rare in Caucasians. The mechanisms responsible for the predilection of HIVAN in AA are not well understood. In transgenic mouse studies, genetic background plays a vital role in the development of the HIVAN phenotype. Larger studies in humans have been initiated to study genetic polymorphisms responsible for HIVAN. As our case illustrates, HIVAN should be considered in Caucasian patients with HIV infection complicated by nephrotic syndrome and renal failure.

Immune complex renal disease and human immunodeficiency virus infection

Immune complex glomerulonephritis is a common diagnosis in renal biopsy series of human immunodeficiency virus (HIV)-infected patients. There are a variety of glomerulonephritides associated with HIV infection, including IgA nephropathy, membranoproliferative glomerulonephritis, membranous nephropathy, lupus-like glomerulonephritis, immunotactoid glomerulopathy, and fibrillary glomerulonephritis. In addition, HIV-related proteins may be implicated in circulating immune complexes directly related to a response to the infection. In some cases, the relationship of the HIV infection to the glomerulonephritis is unclear. HIV infection is associated with the development of polyclonal hypergammaglobulinemia, which can promote the development of circulating immune complexes. It is not clear if HIV-associated glomerulonephritis is caused by the passive trapping of these circulating immune complexes or the in situ deposition of antibodies binding to HIV viral antigens. Some renal lesions that are seen in the setting of HIV infection more likely may be related to the presence of a co-infection such as hepatitis C virus infection. The optimal therapy for immune complex glomerulonephritis in the setting of HIV infection is unknown. Because of the underlying immunosuppressed state of many HIV-infected patients, caution with traditional cytotoxic therapies is advised. The role of antiretroviral therapy in modifying the course of these renal lesions is unclear.

Baseline renal insufficiency and risk of death among HIV-infected adults on antiretroviral therapy in Lusaka, Zambia

OBJECTIVE

To examine the association between baseline renal insufficiency and mortality among adults initiating antiretroviral therapy (ART) in an urban African setting.

DESIGN

Open cohort evaluation.

METHODS

We examined mortality according to baseline renal function among adults initiating ART in Lusaka, Zambia. Renal function was assessed by the Cockcroft-Gault method, the Modification of Diet in Renal Disease equation, and serum creatinine.

RESULTS

From April 2004 to September 2007, 25 779 individuals started ART with an available creatinine measurement at baseline. When creatinine clearance was calculated by the Cockcroft-Gault method, 8456 (33.5%) had renal insufficiency: 73.5% were mild (60-89 ml/min), 23.4% moderate (30-59 ml/min), and 3.1% severe (<30 ml/min). Risk for mortality at or before 90 days was elevated for those with mildly [adjusted hazard ratio (AHR)(1/4)1.7; 95% confidence interval (95% CI)(1/4)1.5-1.9], moderately (AHR(1/4)2.3; 95% CI(1/4)2.0-2.7), and severely (AHR(1/4)4.3; 95% CI(1/4)3.1-5.5) reduced creatinine clearance. Mild (AHR(1/4)1.4; 95% CI(1/4)1.2-1.6), moderate (AHR(1/4)1.9; 95% CI(1/4)1.5-2.3), and severe (AHR(1/4)3.6; 95% CI(1/4) 2.4-5.5) insufficiency were also associated with increased mortality after 90 days, when compared with those with normal renal function. Trends were similar when renal function was estimated with Modification of Diet in Renal Disease or serum creatinine.

CONCLUSION

Renal insufficiency at time of ART initiation was prevalent and associated with increased mortality risk among adults in this population. These results have particular relevance for settings like Zambia, where tenofovir--a drug with known nephrotoxicity--has been adopted as part of first-line therapy. This emphasizes the need for resource-appropriate screening algorithms for renal disease, both as part of ART eligibility and pretreatment assessment.

Infection and glomerulonephritis

Glomerular injury, occurring either as primary glomerular disease or as part of a systemic disease process, is usually a result of immune-mediated mechanisms. The morphologic reaction pattern has a diverse spectrum of appearance, ranging from normal by light microscopy in minimal change disease to crescentic forms of glomerulonephritis, with conspicuous disruption of the normal glomerular morphology. The mechanisms of glomerular immune deposit formation include trapping of circulating antigen-antibody complexes and the in situ formation of immune complexes within the glomerulus. While the majority of postinfectious immune-complex-mediated glomerulonephritides are believed to result from the deposition of circulating antigen-antibody complexes, preformed outside of the kidney and secondarily deposited in the kidney, the notion of forming in situ antigen-antibody complexes to either planted antigens or to integral structural components of the glomerulus, through "cross-reacting" autoimmune reactions, is gaining popularity in a variety of forms of glomerulonephritides. Patients with HIV infection may develop a spectrum of renal pathology, the glomerular manifestations of which include both antigen-antibody complex and nonimmune-complex-mediated pathogenetic mechanisms. Similarly, patients with Streptococcal infections, Hepatitis B virus, or Hepatitis C virus infection may develop a spectrum of glomerulonephritides, which are predominantly immune-complex-mediated. Therapy for glomerular diseases due to HIV, hepatitis B, or C virus infections remains a challenge.

HIV-1 infection and the kidney: an evolving challenge in HIV medicine

With the advent of highly active antiretroviral therapy (HAART), the incidence of opportunistic infections has declined substantially, and cardiovascular, liver, and renal diseases have emerged as major causes of morbidity and mortality in individuals with human immunodeficiency virus (HIV). Acute renal failure is common in HIV-infected patients and is associated with acute infection and medication-related nephrotoxicity. HIV-associated nephropathy is the most common cause of chronic kidney disease in HIV-positive African American populations and may respond to HAART. Other important HIV-associated renal diseases include HIV immune complex kidney diseases and thrombotic microangiopathy. The increasing importance of non-HIV-associated diseases, such as diabetes mellitus, hypertension, and vascular disease, to the burden of chronic kidney disease has been recognized, focusing attention on prevention and control of these diseases in HIV-positive individuals. HIV-positive individuals who experience progression to end-stage renal disease and who have undetectable HIV-1 viral loads while receiving HAART should be evaluated for renal transplant. Emerging evidence suggests that HIV-positive individuals may have graft and patient survival comparable to HIV-negative individuals. Several studies suggest that HIV-1 can potentially infect renal cells, and HIV transgenic mice have clarified the roles of a number of HIV proteins in the pathogenesis of HIV-associated renal disease. Host factors may modify disease expression at the level of cytokine networks and the renal microvasculature and contribute to the pathogenic effects of HIV-1 infection on the kidney.

Immunotactoid glomerulonephritis in a child with HIV infection: a case report

Renal disease is a common complication of human immunodeficiency virus (HIV) infection in adults. In children, however, HIV pathology of the gastrointestinal and respiratory tracts predominates, whereas renal disease is often an incidental finding. In this report, we describe a child with stage III HIV infection associated with immunotactoid glomerulonephritis (IT). The patient was referred for investigation of idiopathic nephrotic syndrome. Electron microscopy of his renal biopsy specimen revealed numerous electron-dense microtubular deposits, arranged in parallel fashion, consistent with a diagnosis of IT. He received highly active antiretroviral therapy (HAART) as well as corticosteroids and is currently in remission. To our knowledge, this is the first report of IT in a child.