A cross-sectional study of HIV-seropositive patients with varying degrees of proteinuria in South Africa

HIV-associated nephropathy in the setting of maximal virologic suppression

Human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) is most frequently seen as a late manifestation in adult patients with a high viral load and low T-helper cell (CD4) counts. We report a case of HIVAN in a black Zimbabwean teenager in whom the disease activity was well suppressed for years following highly active antiretroviral therapy (HAART). Proteinuria was absent at 9 years of age when he presented with vertically transmitted HIV infection. Within a few months of HAART, the viral load became undetectable and CD4 count was normalised. Nephrotic range proteinuria, with preserved renal function, developed approximately 4 years later despite excellent HIV disease suppression. Renal biopsy showed non-collapsing focal segmental glomerular sclerosis changes compatible with HIVAN. Although the role of other unknown factors in the disease pathogenesis could not be totally excluded, this case demonstrates that HIVAN can still occur in HIV-infected children despite excellent HAART and that the disease manifestations and outcome may differ from those reported in previous studies.

Urinary NGAL is a useful clinical biomarker of HIV-associated nephropathy

BACKGROUND

Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is expressed by kidney tubules that are acutely damaged, but few studies have investigated the association of neutrophil gelatinase-associated lipocalin (NGAL) with different forms of chronic kidney disease (CKD). HIV-associated nephropathy (HIVAN) is a progressive form of CKD characterized by collapsing focal segmental glomerulosclerosis and microcytic tubular dilatation that typically leads to end-stage renal disease (ESRD).

METHODS

Previously, we reported that microcystic tubular dilatations specifically expressed NGAL RNA, implying that the detection of uNGAL protein could mark advanced HIVAN. To test this idea, we performed a comparative study of diverse proteinuric glomerulopathies in 25 patients who were HIV positive.

RESULTS

Eighteen patients had HIVAN and seven had other glomerulopathies (four membranoproliferative glomerulonephritis, one membranous glomerulonephritis, one amyloid and one malarial GN). HIVAN and non-HIVAN patients did not differ with respect to age, ethnicity, serum creatinine, estimated GFR, proteinuria or the prevalence of hypocomplementemia (6 versus 29%, P = 0.18), but HIVAN patients were less likely to have HCV infections. HIVAN patients expressed 4-fold higher levels of uNGAL than the patients with other glomerulopathies [387 ± 338 versus 94 ± 101 μg/g urine creatinine (uCr), P = 0.02]. A cutpoint of 121.5 μg uNGAL/g uCr demonstrated 94% sensitivity and 71% specificity for the diagnosis of HIVAN, with an area under the receiver operator characteristic curve of 0.88.

CONCLUSION

In summary, while HIVAN disease is currently diagnosed only by kidney biopsy, uNGAL can distinguish HIVAN from other proteinuric glomerulopathies in the HIV-infected patient, likely because of its specific expression from characteristic microcysts.

Improved antiretroviral treatment outcome in a rural African setting is associated with cART initiation at higher CD4 cell counts and better general health condition

BACKGROUND

Data on combination antiretroviral therapy (cART) in remote rural African regions is increasing.

METHODS

We assessed prospectively initial cART in HIV-infected adults treated from 2005 to 2008 at St. Francis Designated District Hospital, Ifakara, Tanzania. Adherence was assisted by personal adherence supporters. We estimated risk factors of death or loss to follow-up by Cox regression during the first 12 months of cART.

RESULTS

Overall, 1,463 individuals initiated cART, which was nevirapine-based in 84.6%. The median age was 40 years (IQR 34-47), 35.4% were males, 7.6% had proven tuberculosis. Median CD4 cell count was 131 cells/μl and 24.8% had WHO stage 4. Median CD4 cell count increased by 61 and 130 cells/μl after 6 and 12 months, respectively. 215 (14.7%) patients modified their treatment, mostly due to toxicity (56%), in particular polyneuropathy and anemia. Overall, 129 patients died (8.8%) and 189 (12.9%) were lost to follow-up. In a multivariate analysis, low CD4 cells at starting cART were associated with poorer survival and loss to follow-up (HR 1.77, 95% CI 1.15-2.75, p=0.009; for CD4<50 compared to >100 cells/μl). Higher weight was strongly associated with better survival (HR 0.63, 95% CI 0.51-0.76, p<0.001 per 10 kg increase).

CONCLUSIONS

cART initiation at higher CD4 cell counts and better general health condition reduces HIV related mortality in a rural African setting. Efforts must be made to promote earlier HIV diagnosis to start cART timely. More research is needed to evaluate effective strategies to follow cART at a peripheral level with limited technical possibilities.

[Pathological peculiarities of chronic kidney disease in patient from sub-Saharan Africa. Review of data from the Democratic Republic of the Congo]

Chronic kidney disease (CKD) is a major global public health problem. But kidney involvement is more common and appears more severe in Africa than in developed countries. The likely causes of end stage renal disease (ESRD) or CKD stage 3 and above in developed countries are diabetes, hypertension and less frequently glomerular diseases. In contrast, in decreasing order in Africa are glomerulopathies, hypertension and diabetes. The reasons for this preponderance of glomerular diseases are not fully known but may be linked to the persistence or reemergence of tropical diseases. This study reviews the kidney involvements more associated with common tropical diseases including HIV/AIDS. The most common HIV/AIDS lesion is a specific focal and segmental glomerulosclerosis (FSGS) termed HIV-associated nephropathy (HIV-AN). Renal complications of tropical parasites are heterogenous. Various glomerulopathies like FSGS occur during various filariasis infections. Schistosoma mansoni is responsible for membranoproliferative glomerulonephritis and amyloidosis. Human African trypanosomiasis is associated with cryoglobulinemic membranoproliferative glomerulonephritis. The Plasmodium malariae is mainly responsible for membranoproliferative glomerulonephritis. Acute patterns (acute tubular necrosis or acute postinfectious glomerulonephritis) are observed during Plasmodium falciparum infection. Several other viral, bacterial or mycobacterial infections like leprosy and tuberculosis still prevalent in Africa can also affect the kidney. Sickle cell disease is responsible for a variety of renal injuries. In conclusion, kidney lesions linked to tropical diseases partly explain the peculiar pattern of CKD of the black race and play a significant role in the current outbreak of the CKD in Subsaharan Africa.

Prevalence of kidney disease in HIV-infected and uninfected Rwandan women

Background

In the United States, HIV-related kidney disease disproportionately affects individuals of African descent; however, there are few estimates of kidney disease prevalence in Africa. We evaluated the prevalence of kidney disease among HIV-infected and uninfected Rwandan women.

Methods

The Rwandan Women's Interassociation Study and Assessment prospectively enrolled 936 women. Associations with estimated glomerular filtration rate (eGFR)<60 mL/min/1.73 m² and proteinuria were assessed in separate logistic regression models.

Results

Among 891 non-pregnant women with available data, 2.4% had an eGFR<60 mL/min/1.73 m² (calculated by the Modification of Diet in Renal Disease equation, MDRD eGFR) and 8.7% had proteinuria ≥1+. The prevalence of decreased eGFR varied markedly depending on the estimating method used, with the highest prevalence by Cockcroft-Gault. Regardless of the method used to estimate GFR, the proportion with decreased eGFR or proteinuria did not differ significantly between HIV-infected and -uninfected women in unadjusted analysis. After adjusting for age and blood pressure, HIV infection was associated with significantly higher odds of decreased MDRD eGFR but not proteinuria.

Conclusion

In a well-characterized cohort of Rwandan women, HIV infection was associated with decreased MDRD eGFR. The prevalence of decreased eGFR among HIV-infected women in our study was lower than that previously reported in African-Americans and in other Central and East African HIV populations, although there was substantial variability depending on the equation used to estimate GFR. Future studies are needed to optimize GFR estimates and to determine the impact of antiretroviral therapy on kidney disease in this population.

Biomarkers of impaired renal function

PURPOSE OF REVIEW

Renal disease is increasingly common as life expectancy of HIV-infected persons continues to improve. Several biomarkers are available for monitoring renal function, although no consensus exists on how best to apply these tools in HIV infection. This review describes recent findings for the more common renal biomarkers.

RECENT FINDINGS

Although widely used in clinical practice, creatinine-based estimates of glomerular filtration rate have not been validated in HIV infection. Serum cystatin C has been proposed as a more sensitive marker of renal dysfunction in HIV infection, although it may also reflect systemic inflammation. Screening for proteinuria and albuminuria allows identification of patients at higher risk of kidney disease and other adverse outcomes. Fanconi syndrome, which has been associated with tenofovir use, is associated with severe tubular proteinuria, and several low molecular weight proteins, including retinol-binding protein, β2-microglobulin, and neutrophil gelatinase-associated lipocalin have been studied as markers of tubular dysfunction. Studies have reported a high prevalence of subclinical proximal tubular dysfunction in patients receiving antiretroviral therapy.

SUMMARY

Future studies are needed to determine the optimal biomarkers for the detection and monitoring of renal disease in HIV.

Treatment of HIV-associated nephropathies

In patients with HIV, the use of highly active antiretroviral therapy has improved life expectancy. At the same time, this increase in life expectancy has been associated with a higher frequency of chronic kidney disease due to factors other than HIV infection. Besides HIV-associated nephropathy, a number of different types of immune complex and non-immune complex-mediated processes have been identified on kidney biopsies, including vascular disease (nephrosclerosis), diabetes, and drug-related renal injury. In this setting, renal biopsy needs to be considered in order to obtain the correct diagnosis in individual patients with HIV and kidney impairment. Many issues regarding the optimal treatment of the different pathological processes affecting the kidneys of these patients have remained unresolved. Further research is needed in order to optimize treatment and renal outcomes in patients with HIV and kidney disease.

Expert opinion on pharmacotherapy of kidney disease in HIV-infected patients

INTRODUCTION

Human immunodeficiency virus (HIV) infection is associated with the development of a wide spectrum of kidney diseases. HIV-associated nephropathy (HIVAN) is the most common cause of chronic kidney disease (CKD) in HIV-infected individuals and predominantly affects patients of African ancestry. HIVAN is a leading cause of end-stage renal disease (ESRD) among African-Americans.

AREAS COVERED

An overview of the spectrum of kidney disease in patients with HIV is given. Current pharmacologic interventions to treat kidney disease in HIV are discussed. This review will enhance knowledge regarding the most common causes of kidney disease in HIV-infected patients. An understanding of the principles related to pharmacotherapy in HIV-infected patients with kidney disease will also be gained.

EXPERT OPINION

Kidney disease is an important cause of morbidity and mortality in HIV-infected patients. The most common cause of chronic kidney disease in this population is HIV-associated nephropathy, which is caused by viral infection of the renal epithelium. Several medications that are commonly used in HIV-infected patients can have adverse effects on the kidneys and the doses of many antiretroviral medications need to be adjusted in patients with impaired renal function.

The molecular pathogenesis of HIV-1 associated nephropathy: recent advances

HIV-1-associated nephropathy (HIVAN) is a major complication of HIV-1 infection, frequently resulting in kidney failure. HIVAN arises due to HIV-1-induced dysregulation of podocytes, the glomerular epithelial cells that establish and maintain the kidney filtration barrier. Host genetic factors are important for the development of HIVAN. The risk of HIVAN is greatest in populations of African ancestry, and is attributable to a genetic variation at the APOL1 locus on chromosome 22. Mouse models of HIVAN enable delineation of dysregulated pathways underlying disease. Identification of HIVAN susceptibility loci in a mouse model, combined with expression quantitative trait locus mapping, has demonstrated that murine HIVAN loci transregulate podocyte gene expression. HIV-1 induces perturbations in podocyte expression response, suggesting that HIV-1 potentially interferes with compensatory pathways that normally restore cellular homeostasis in the face of genetic mutations. These findings present a framework for identification of podocyte transregulators and reconstruction of the molecular networks connecting susceptibility genes to the development of nephropathy.

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.

Changes in the renal function after tenofovir-containing antiretroviral therapy initiation in a Senegalese cohort (ANRS 1215)

To describe and compare the changes in renal function between HIV-1 infected adult patients receiving antiretroviral therapy (ART) with and without tenofovir (TDF). The population consisted of 40 patients starting a TDF-containing regimen and 388 patients starting regimen not containing TDF, and followed during 42 months. The estimated glomerular filtration rate (eGFR) was calculated using the Cockroft-Gault and MDRD equations and modeled separately for the first 12 months and the subsequent period. Between baseline and 12 months, the eGFR decreased significantly in patients receiving TDF (-10.40 ml/min), whereas it increased in the other +4.33 ml/min). A significant variability in the eGFR trajectories of patients receiving TDF was observed; 12 (30%) of them experienced a persistent decrease, 5 (12%) had an initial transient increase, and 23 (58%) a steady slow increase in eGFR. The characteristics at baseline of the patients with persistent decrease were not different from the other patients but their immune reconstitution was impaired. After 12 months, patients receiving TDF experienced a higher rate of transition from mild renal impairment (60-90 ml/min/1.73 m(2)) to moderate renal impairment (30-60 ml/min/1.73 m(2)) when compared with patients not receiving TDF. A significant though moderate decline in the renal function was observed in one-third of the patients receiving TDF compared to patients not receiving TDF. Moreover, this impairment was persistent after the first year of treatment.

A survey of the management, control, and complications of diabetes mellitus in patients attending a diabetes clinic in Blantyre, Malawi, an area of high HIV prevalence

The aim of this study was to describe the current status of diabetes care in an urban diabetes clinic in Malawi and the prevalence of human immunodeficiency virus (HIV) in this population, investigating possible associations between HIV and diabetes. A systematic prospective survey of patients attending the diabetes clinic at a teaching hospital in Blantyre, Malawi was conducted. Six hundred twenty patients were assessed. Seventy-four percent had glycosylated hemoglobin (HbA1C) > 7.5%. Systolic blood pressure was > 140 mm Hg in 52% of patients. Hypertension was more common in patients with raised creatinine (P < 0.003), retinopathy (P = 0.01), and stroke (P < 0.0002). Microvascular complication rates were high, specifically nephropathy (34.7%), retinopathy (34.7%), and neuropathy (46.4%). HIV seroprevalence was 13.7%. HIV-positive subjects had a lower body mass index (BMI) and lower fasting blood sugar, and they were more likely to have albuminuria (48.0% versus 33.3%; P < 0.05). Control of glycemia and hypertension were poor, and microvascular complications were common. Nephropathy in diabetic patients may be affected by HIV status.

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.

The acute, the chronic and the news of HIV-related renal disease in Africa

The burden of renal disease in human immunodeficiency virus (HIV) and AIDS patients living in Africa is adversely influenced by inadequate socio-economic and health care infrastructures. Acute kidney injury in HIV-positive patients, mainly as a result of acute tubular necrosis, may arise from a combination of hemodynamic, immunological, and toxic insult. A variety of histopathological forms of chronic kidney disease is also seen in HIV patients; HIV-associated nephropathy (HIVAN) and immune complex disease may require different treatment strategies, which at present are unknown. The role of host and viral genetics is still to be defined, especially in relation to the different viral clades found in various parts of the world and within Africa. The arrival and availability of highly active antiretroviral therapy in Africa has given impetus to research into the outcome of the renal diseases that are found in those with HIV. It has also generated a new look into policies governing dialysis and transplantation in this group where previously there were none.

Prevalence of proteinuria among HIV-infected children attending a tertiary hospital in Lagos, Nigeria

Sub-Saharan Africa is the epicentre of the HIV pandemic but there are few reports of HIV-related kidney diseases in children in this region. This study aimed to determine the prevalence of proteinuria in HIV-infected children at the Lagos University Teaching Hospital. Proteinuria was determined using urine protein-creatinine ratio. CD4+ cell count was determined for all the HIV-infected children. The mean age of the HIV-infected children was 74.4 +/- 35.6 months with a male: female ratio of 3:2. Compared with 6% of the 50 controls 20.5% of the 88 HIV-infected children had proteinuria (p = 0.026). Of 20 children with advanced clinical stage 40% had proteinuria compared with 14.7% of 68 children with milder stage (p = 0.004). Similarly, proteinuria was commoner among those with severe immunosuppression (p = 0.014). HAART use was not associated with significant difference in proteinuria prevalence (p = 0.491). Proteinuria was frequent among HIV-infected children, especially among those with advanced disease.

Burden of chronic kidney disease: an international perspective

CKD is associated with increased cardiovascular mortality and a loss of disability-adjusted life years. Diseases of the genitourinary system were responsible for 928,000 deaths and 14,754,000 disability-adjusted life years in 2004. However, the absence of kidney registries in most of the low- and middle-income countries has made it difficult to ascertain the true burden of CKD in these countries. The global increase in the incidence and prevalence of CKD is being driven by the global increase in the prevalence of diabetes mellitus, hypertension, obesity, and aging. Most patients in low- and middle-income countries die because they cannot access renal replacement therapy because of the exorbitant cost. Community surveys have shown that the number of people with end-stage kidney disease is just the tip of the "CKD iceberg." The preventive strategies to stem the tide of CKD should involve educating the population on how to prevent renal disease; identifying those at risk of developing CKD; raising the awareness of the general public, policy makers, and health care workers; modifying the lifestyle of susceptible individuals; detecting early stage of CKD; arresting or hindering the progression of disease; and creating facilities for global assistance.

African ancestry allelic variation at the MYH9 gene contributes to increased susceptibility to non-diabetic end-stage kidney disease in Hispanic Americans

Recent studies identified MYH9 as a major susceptibility gene for common forms of non-diabetic end-stage kidney disease (ESKD). A set of African ancestry DNA sequence variants comprising the E-1 haplotype, was significantly associated with ESKD. In order to determine whether African ancestry variants are also associated with disease susceptibility in admixed populations with differing genomic backgrounds, we genotyped a total of 1425 African and Hispanic American subjects comprising dialysis patients with diabetic and non-diabetic ESKD and controls, using 42 single nucleotide polymorphisms (SNPs) within the MYH9 gene and 40 genome-wide and 38 chromosome 22 ancestry informative markers. Following ancestry correction, logistic regression demonstrated that three of the E-1 SNPs are also associated with non-diabetic ESKD in the new sample sets of both African and Hispanic Americans, with a stronger association in Hispanic Americans. We also identified MYH9 SNPs that are even more powerfully associated with the disease phenotype than the E-1 SNPs. These newly associated SNPs, could be divided into those comprising a haplotype termed S-1 whose association was significant under a recessive or additive inheritance mode (rs5750248, OR 4.21, P < 0.01, Hispanic Americans, recessive), and those comprising a haplotype termed F-1 whose association was significant under a dominant or additive inheritance mode (rs11912763, OR 4.59, P < 0.01, Hispanic Americans, dominant). These findings strengthen the contention that a sequence variant of MYH9, common in populations with varying degrees of African ancestry admixture, and in strong linkage disequilibrium with the associated SNPs and haplotypes reported herein, strongly predisposes to non-diabetic ESKD.

HIV and kidney disease in sub-Saharan Africa

A wide clinical spectrum of renal diseases affects individuals with HIV. These conditions include acute kidney injury, electrolyte and acid-base disturbances, HIV-associated glomerular disease, acute-on-chronic renal disease and adverse side effects related to treatment of HIV. Studies employing varying criteria for diagnosis of kidney disease have reported a variable prevalence of these diseases in patients with HIV in sub-Saharan Africa: 6% in South Africa, 38% in Nigeria, 26% in Côte d'Ivoire, 28% in Tanzania, 25% in Kenya, 20-48.5% in Uganda and 33.5% in Zambia. Results from these studies also suggest that a broader spectrum of histopathological lesions in HIV-associated kidney disease exists in African populations than previously thought. Strategies to prevent or retard progression to end-stage renal disease of HIV-associated kidney conditions should include urinalysis and measurement of kidney function of all people with HIV at presentation. Renal replacement in the form of dialysis and transplantation should be implemented as appropriate. This Review focuses on the available evidence of renal diseases in patients with HIV infection in sub-Saharan Africa and offers practical guidelines to treat these conditions that also take into consideration challenges and obstacles that are specific to sub-Saharan Africa.

Diagnosis and natural history of HIV-associated nephropathy

HIV-associated nephropathy (HIVAN) is a largely distinctive phenotype induced by HIV-1 infection and is the most recognized and detrimental kidney disease in HIV-infected patients. Host and viral characteristics have been implicated in the pathogenesis of HIVAN that may explain its exclusive predilection to patients of African descent. In untreated patients, the disorder is clinically manifested by an acute decline in kidney function, most often in conjunction with high-grade proteinuria and uncontrolled HIV-1 infection. Histologically, proliferating glomerular epithelial cells are the prominent feature of the disease. Data have evolved over the past decade suggesting that highly active antiretroviral therapy (HAART) can change the natural history of HIVAN, not only by preventing its development but also by halting its progression once developed. Consequently, with the widespread use of HAART, the prevalence of HIVAN is declining in Western countries. In contrast, the epidemiology of the disease is not well defined in the poorest areas in the world, which bear a disproportionate share of the HIV-1 epidemic's burden. Corticosteroids and inhibition of the renin-angiotensin axis are recommended as adjunctive agents in treating patients with established HIVAN and are potentially helpful in delaying the need for renal replacement therapy. However, the long-term value and potential risks of using corticosteroids in this population are unclear.

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.

The treatment of HIV-associated nephropathy

Antiretroviral therapy (ART) preserves kidney function in patients with human immunodeficiency virus (HIV)-associated nephropathy (HIVAN). Emerging data also document substantial renal benefits of ART in the general HIV-infected population, which is associated in part with suppression of HIV-1 viral replication. The extent to which the response to ART differs in persons with HIVAN compared with those with other HIV-associated kidney disorders is unknown. Beneficial effects of corticosteroids and angiotensin-converting enzyme inhibitors on kidney function also are suggested by retrospective cohort studies and uncontrolled trials of patients with HIVAN. Underexposure to ART or inadequate ART dosing in HIV-infected patients with CKD may curtail the optimal benefits that may be derived from this therapy.

Interventions for HIV-associated nephropathy

BACKGROUND

Human immunodeficiency virus associated nephropathy (HIVAN) is the most common cause of end stage kidney disease (ESKD) in Human immunodeficiency virus-1 (HIV-1) serotype patients and it mostly affects patients of African descent. It rapidly progresses to ESKD if untreated. The goal of treatment is directed toward reducing HIV-1 replication and/or slowing the progression of chronic kidney disease. The following pharmacological agents have been used for the treatment of HIVAN: antiretrovirals, angiotensin-converting enzyme inhibitors (ACEi), steroids and recently cyclosporin. Despite this, the effect of each intervention is yet to be evaluated.

OBJECTIVES

To evaluate the benefits and harms of adjunctive therapies in the management of HIVAN and its effects on symptom severity and all-cause mortality.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Renal Group's specialised register, MEDLINE, EMBASE, AIDSearch, reference lists of articles and conference proceedings without language restrictions. We searched the international clinical trials registry platform search portal and also contacted individual researchers, research organisations and pharmaceutical companies that manufacture the drugs used for interventions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of any therapy used in the treatment of HIVAN.

DATA COLLECTION AND ANALYSIS

We independently screened the search outputs for relevant studies and to retrieve full articles when necessary. We applied the inclusion criteria to identify four relevant ongoing studies, one is ongoing while the remaining two have completed recruitment and are yet to be published. The fourth study was suspended for an unknown reason.

MAIN RESULTS

No completed RCTs or quasi-RCTs were identified to be included in the study.

AUTHORS' CONCLUSIONS

There is no RCT-based evidence upon which to base guidelines for the treatment of HIVAN. However, steroids and ACEI appear to improve the kidney function of patients in the observational studies that were identified. This review highlights the need for good quality RCTs to address the effects of interventions for treating this group.

Renal impairment in a rural African antiretroviral programme

Background

There is little knowledge regarding the prevalence and nature of renal impairment in African populations initiating antiretroviral treatment, nor evidence to inform the most cost effective methods of screening for renal impairment. With the increasing availability of the potentially nephrotixic drug, tenofovir, such information is important for the planning of antiretroviral programmes

Methods

(i) Retrospective review of the prevalence and risk factors for impaired renal function in 2189 individuals initiating antiretroviral treatment in a rural African setting between 2004 and 2007 (ii) A prospective study of 149 consecutive patients initiating antiretrovirals to assess the utility of urine analysis for the detection of impaired renal function. Severe renal and moderately impaired renal function were defined as an estimated GFR of ≤ 30 mls/min/1.73 m² and 30–60 mls/min/1.73 m² respectively. Logistic regression was used to determine odds ratio (OR) of significantly impaired renal function (combining severe and moderate impairment). Co-variates for analysis were age, sex and CD4 count at initiation.

Results

(i) There was a low prevalence of severe renal impairment (29/2189, 1.3% 95% C.I. 0.8–1.8) whereas moderate renal impairment was more frequent (287/2189, 13.1% 95% C.I. 11.6–14.5) with many patients having advanced immunosuppression at treatment initiation (median CD4 120 cells/μl). In multivariable logistic regression age over 40 (aOR 4.65, 95% C.I. 3.54–6.1), male gender (aOR 1.89, 95% C.I. 1.39–2.56) and CD4<100 cells/ul (aOR 1.4, 95% C.I. 1.07–1.82) were associated with risk of significant renal impairment (ii) In 149 consecutive patients, urine analysis had poor sensitivity and specificity for detecting impaired renal function.

Conclusion

In this rural African setting, significant renal impairment is uncommon in patients initiating antiretrovirals. Urine analysis alone may be inadequate for identification of those with impaired renal function where resources for biochemistry are limited.

[Hypertension, HIV infection, and highly active antiretroviral therapy]

The decline in mortality resulting from the use of highly active antiretroviral therapy (HAART) has been accompanied by an increase in metabolic complications that produce accelerated atherosclerosis. Hypertension is one of the most important cardiovascular risk factors. Little is known about the impact of HAART on blood pressure, and it is uncertain whether chronic HIV infection or HAART have a role in the development of hypertension. In this study, the research on the relationships between hypertension and HIV infection published to date is reviewed. Antiretroviral therapy appears to have a modest impact on blood pressure and to be partially mediated by the metabolic changes occurring with this treatment.

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.

Accelerated development of collapsing glomerulopathy in mice congenic for the HIVAN1 locus

HIV-1 transgenic mice on the FVB/NJ background (TgFVB) are a well validated model of HIV-associated nephropathy (HIVAN). A mapping study between TgFVB and CAST/EiJ (CAST) strains showed this trait to be influenced by a major susceptibility locus on chromosome 3A1-A3 (HIVAN1), with CAST alleles associated with increased risk of disease. We introgressed a 50 Mb interval, encompassing this HIVAN1 locus, from CAST into the TgFVB genome (TgFVB-HIVAN1(CAST) congenic mice). Compared to the TgFVB strain, these congenic mice developed an earlier onset of proteinuria, a rapid progression to kidney failure, and increased mortality. A prospective study of these congenic mice also showed that they had a significantly greater histologic and biochemical evidence of glomerulopathy with one-third of mice developing global glomerulosclerosis by 6 weeks of age. An F2 cross between TgFVB and the congenic mice identified a significant linkage (LOD=3.7) to a 10 cM interval within the HIVAN1 region between D3Mit167 and D3Mit67 resulting in a 60% reduction of the original interval. These data independently confirm that a gene on chromosome 3A1-A3 increases susceptibility to HIVAN, resulting in early onset and rapid progression of kidney disease. These mice represent a new model to study the development and progression of collapsing glomerulopathy.

The spectrum of kidney disease in patients with AIDS in the era of antiretroviral therapy

With prolonged survival and aging of the HIV-infected population in the era of antiretroviral therapy, biopsy series have found a broad spectrum of HIV-related and co-morbid kidney disease in these patients. Our study describes the variety of renal pathology found in a prospective cohort of antiretroviral-experienced patients (the Manhattan HIV Brain Bank) who had consented to postmortem organ donation. Nearly one-third of 89 kidney tissue donors had chronic kidney disease, and evidence of some renal pathology was found in 75. The most common diagnoses were arterionephrosclerosis, HIV-associated nephropathy and glomerulonephritis. Other diagnoses included pyelonephritis, interstitial nephritis, diabetic nephropathy, fungal infection and amyloidosis. Excluding 2 instances of acute tubular necrosis, slightly over one-third of the cases would have been predicted using current diagnostic criteria for chronic kidney disease. Based on semi-quantitative analysis of stored specimens, pre-mortem microalbuminuria testing could have identified an additional 12 cases. Future studies are needed to evaluate the cost-effectiveness of more sensitive methods for defining chronic kidney disease, in order to identify HIV-infected patients with early kidney disease who may benefit from antiretroviral therapy and other interventions known to delay disease progression and prevent complications.

HIV-associated nephropathy: clinical presentation, pathology, and epidemiology in the era of antiretroviral therapy

The classic kidney disease of human immunodeficiency virus (HIV) infection, HIV-associated nephropathy, is characterized by progressive acute renal failure, often accompanied by proteinuria and ultrasound findings of enlarged, echogenic kidneys. Definitive diagnosis requires kidney biopsy, which shows collapsing focal segmental glomerulosclerosis with associated microcystic tubular dilatation and interstitial inflammation. Podocyte proliferation is a hallmark of HIV-associated nephropathy, although this classic pathology is observed less frequently in antiretroviral-treated patients. The pathogenesis of HIV-associated nephropathy involves direct HIV infection of renal epithelial cells, and the widespread introduction of combination antiretroviral therapy has had a significant impact on the natural history and epidemiology of this unique disease. These observations have established antiretroviral therapy as the cornerstone of treatment for HIV-associated nephropathy in the absence of prospective clinical trials. Adjunctive therapy for HIV-associated nephropathy includes angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers, as well as corticosteroids in selected patients with significant interstitial inflammation or rapid progression.

Kidney disease in HIV-positive children

Before the era of highly active antiretroviral therapy, more than 40% of human immunodeficiency virus (HIV)-infected children experienced renal complications. In sub-Saharan Africa, approximately 2.1 million children are infected with HIV-1. In the absence of antiretroviral therapy, young African children frequently died of AIDS-related complications before renal diseases could be manifested or diagnosed. As antiretroviral therapy has become more available, and their survival has increased, our experience in treating kidney disease in HIV-infected children has improved. This article discusses relevant clinical and pathologic findings related to kidney disease in HIV-infected children.

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.

Renal disease in patients with HIV infection: epidemiology, pathogenesis and management

With the introduction of highly active antiretroviral therapy, we have witnessed prolonged survival with the potential for normal life expectancy in HIV-infected individuals. With improved survival and increasing age, HIV-infected patients are increasingly likely to experience co-morbidities that affect the general population, including kidney disease. Although HIV-associated nephropathy, the most ominous kidney disease related to the direct effects of HIV, may be prevented and treated with antiretrovirals, kidney disease remains an important issue in this population. In addition to the common risk factors for kidney disease of diabetes mellitus and hypertension, HIV-infected individuals have a high prevalence of other risk factors, including hepatitis C, cigarette smoking and injection drug use. Furthermore, they have exposures unique to this population, including antiretrovirals and other medications. Therefore, the differential diagnosis is vast. Early identification (through efficient screening) and definitive diagnosis (by kidney biopsy when indicated) of kidney disease in HIV-infected individuals are critical to optimal management. Earlier interventions with disease-specific therapy, often with the help of a nephrologist, are likely to lead to better outcomes. In those with chronic kidney disease, interventions, such as aggressive blood pressure control with the use of ACE inhibitors or angiotensin receptor antagonists where tolerated, tight blood glucose control in those with diabetes, and avoidance of potentially nephrotoxic medications, can slow progression and prevent end-stage renal disease. Only with greater awareness of kidney-disease manifestations and their implications in this particularly vulnerable population will we be able to achieve success in confronting this growing problem.

Antiretroviral therapy improves renal function among HIV-infected Ugandans

Renal dysfunction is a severe complication of advanced HIV disease. We evaluated the impact of highly active antiretroviral therapy (HAART) on renal function among HIV-infected Ugandans in the Home-Based AIDS Care clinical trial. The patients presented with symptomatic HIV disease or CD4 cell count < or = 250 cells/mm(3) and creatinine clearances above 25 ml/min determined by the Cockcroft-Gault equation. Of the 508 patients at baseline, 8% had a serum creatinine over 133 micromol/l and about 20% had reduced renal function evidenced by a creatinine clearance between 25 and 50 ml/min. After 2 years of HAART, the median serum creatinine was significantly decreased by 16% while the median creatinine clearance significantly increased 21%. The median creatinine clearance of patients with renal dysfunction at baseline, increased by 53% during 2 years of treatment. In multivariable analysis, a baseline creatinine above 133 micromol/l, a weight gain of more than 5 kg over the 2 years, female gender and a WHO stage 4 classification were all associated with greater improvements in creatinine clearance on HAART. Our study shows that renal dysfunction was common with advanced HIV disease in Uganda but this improved following 2 years of HAART.

Proteinuria in children infected with the human immunodeficiency virus

OBJECTIVES

To determine the prevalence of proteinuria in a large cohort of children infected with the human immunodeficiency virus (HIV) and their longitudinal progression during treatment with highly active antiretroviral therapy.

STUDY DESIGN

In a retrospective cohort study, 286 children infected with HIV were monitored with quantitative assays of proteinuria from January 1998 through January 2007, with monitoring of viral load, lymphocyte profiles, kidney function, and mortality rates. Proteinuria was quantitated by urine protein to creatinine ratio (Upr/cr).

RESULTS

Ninety-four (33%) had proteinuria at baseline. Of these, 32 (11.2%) had nephrotic range proteinuria (Upr/cr > or = 1.0). Initial screening was at 11 +/- 0.3 years of age, with an average follow-up of 5.6 +/- 0.1 years. The mortality rate was significantly greater in those with proteinuria. During the period of observation, 15 patients with nephrotic proteinuria died or had development of end-stage renal disease, and 16 showed improvement. Of those with intermediate range proteinuria (Upr/cr > or = 0.2 < 1.0), 3 progressed to nephrotic range proteinuria, and 39 (63%) showed resolution of the proteinuria (Upr/cr < 0.2). Improvement in proteinuria was correlated with decreasing viral load (r = 0.5; P < .01).

CONCLUSIONS

Control of viral load with highly active antiretroviral therapy appears to prevent the progression of HIV-associated renal disease and improve survival rates in infected children.

Microalbuminuria associated with indicators of inflammatory activity in an HIV-positive population

Background. The survival of human immunodeficiency virus (HIV)-infected patients has increased significantly since the introduction of combination antiretroviral therapy, leading to the development of important long-term complications including cardiovascular disease (CVD) and renal disease. Microalbuminuria, an indicator of glomerular injury, is associated with an increased risk of progressive renal deterioration, CVD and mortality. However, the prevalence of microalbuminuria has barely been investigated in HIV-infected individuals.

Methods. Based on three prospective urine samples in an unselected nonhypertensive, nondiabetic HIV-positive cohort (n = 495), we analysed the prevalence of microalbuminuria and compared the Caucasian share with that of a nonhypertensive, nondiabetic population-based control group (n = 2091). Significant predictors for microalbuminuria were analysed within the HIV-positive cohort.

Results. The prevalence of microalbuminuria was 8.7% in the HIV-infected cohort, which is three to five times higher than that in the general population. HIV-infected patients with microalbuminuria were older, and had higher blood pressure, longer duration of HIV infection, higher serum beta 2-microglobulin, higher serum creatinine and a reduced glomerular filtration rate of ≤90 mL/min, compared with those with normal albumin excretion. In multivariate analysis, systolic blood pressure, serum beta 2-microglobulin and duration of HIV infection were found to be independent predictors of microalbuminuria.

Conclusions. Our findings indicate that in addition to haemodynamic effects, inflammatory activity may be implicated as a cause of the development of microalbuminuria. With respect to the increasing risk of developing CVD or renal diseases and mortality, the high prevalence of microalbuminuria in HIV-infected individuals warrants special attention.

HIV and the kidney

Kidney disease is an important complication of HIV infection. Antiretroviral therapy has dramatically improved the life expectancy of HIV-infected patients with end-stage renal disease. Renal replacement therapy, including kidney transplantation, should be offered to HIV-positive patients.

Severe renal dysfunction and risk factors associated with renal impairment in HIV-infected adults in Africa initiating antiretroviral therapy

BACKGROUND

We sought to investigate renal function in previously untreated symptomatic human immunodeficiency virus (HIV)-infected adults with CD4(+) cell counts of <200 cells/mm(3) who were undergoing antiretroviral therapy (ART) in Africa.

METHODS

The study was an observational analysis within a randomized trial of ART management strategies that included 3316 participants with baseline serum creatinine levels of < or =360 micromol/L. Creatinine levels were measured before ART initiation, at weeks 4 and 12 of therapy, and every 12 weeks thereafter. We calculated estimated glomerular filtration rate (eGFR) using the Cockcroft-Gault formula. We analyzed the incidence of severely decreased eGFR (<30 mL/min/1.73 m(2)) and changes in eGFR to 96 weeks, considering demographic data, type of ART, and baseline biochemical and hematological characteristics as predictors, using random-effects models.

RESULTS

Sixty-five percent of the participants were women. Median values at baseline were as follows: age, 37 years; weight, 57 kg; CD4(+) cell count, 86 cells/mm(3); and eGFR, 89 mL/min/1.73 m(2). Of the participants, 1492 (45%) had mild (> or =60 but <90 mL/min/1.73 m(2)) and 237 (7%) had moderate (> or =30 but <60 mL/min/1.73 m(2)) impairments in eGFR. First-line ART regimens included zidovudine-lamivudine plus tenofovir disoproxil fumarate (for 74% of patients), nevirapine (16%), and abacavir (9%) (mostly nonrandomized allocation). After ART initiation, the median eGFR was 89-91 mL/min/1.73 m(2) for the period from week 4 through week 96. Fifty-two participants (1.6%) developed severe reductions in eGFR by week 96; there was no statistically significant difference between these patients and others with respect to first-line ART regimen received (P = .94). Lower baseline eGFR or hemoglobin level, lower body mass index, younger age, higher baseline CD4(+) cell count, and female sex were associated with greater increases in eGFR over baseline, with small but statistically significant differences between regimens (P < .001 for all).

CONCLUSIONS

Despite screening, mild-to-moderate baseline renal impairment was relatively common, but these participants had greatest increases in eGFR after starting ART. Severe eGFR impairment was infrequent regardless of ART regimen and was generally related to intercurrent disease. Differences between ART regimens with respect to changes in eGFR through 96 weeks were of marginal clinical relevance, but investigating longer-term nephrotoxicity remains important.

Frequency and associated factors of proteinuria in Iranian HIV-positive patients

BACKGROUND

Screening HIV-positive patients for proteinuria would result in early recognition of HIV-associated nephropathy (HIVAN). This would allow diagnosis and treatment of HIVAN at an early stage and hence prevent further disease progression. This study was undertaken to determine the frequency of proteinuria and its associated factors in Iranian HIV-positive patients.

METHODS

In this study, 171 HIV-positive patients were screened for proteinuria. Proteinuria was defined as > or =1+ protein on the urine dipstick. A questionnaire was used to collect patient sociodemographic and clinical data. Hepatitis B surface antigen (HBsAg), hepatitis C antibody (anti-HCV), serum albumin, and creatinine were tested in all patients. CD4 counts were obtained by flow cytometry.

RESULTS

Out of 171 HIV-positive patients, 21 (12.3%) had proteinuria. There were no significant differences between patients with and without proteinuria with regard to age, sex, risk behaviors for HIV acquisition, stage of infection, concurrent antiretroviral therapy, systolic and diastolic blood pressure, serum albumin and creatinine, glomerular filtration rate (GFR), and presence of anti-HCV or HBsAg. Patients with proteinuria had a lower CD4 count and creatinine clearance than those without proteinuria.

CONCLUSION

Proteinuria was relatively high in Iranian HIV-positive patients. The group at higher risk was that of patients with lower CD4 counts and creatinine clearance.

Suppression of HIV-1 replication by antiretroviral therapy improves renal function in persons with low CD4 cell counts and chronic kidney disease

OBJECTIVE

To examine the association between changes in glomerular filtration rates (GFR) and antiretroviral therapy (ART)-mediated suppression of plasma HIV-1 viremia.

DESIGN

: Observational, prospective, multicenter cohort study.

INTERVENTION

ART regimens or treatment strategies in HIV-1-infected subjects were implemented through randomized clinical trials; 1776 ambulatory subjects from these trials also enrolled in this cohort study.

METHOD

The association between suppression of viremia and GFR changes from baseline was examined using the abbreviated Modification of Diet and Renal Disease equation in mixed effects linear models.

RESULTS

GFR improvement was associated with ART-mediated suppression of plasma viremia in subjects with both chronic kidney disease stage > or = 2 and low baseline CD4 cell counts (< 200 cells/microl). In this subset, viral suppression (by > 1.0 log10 copies/ml or to < 400 copies/ml) was associated with an average increase in GFR of 9.2 ml/min per 1.73 m(2) from baseline (95% confidence interval, 1.6-16.8; P = 0.02) over a median follow-up of 160 weeks. The magnitude of this association increased in subjects who had greater baseline impairment of renal function, and it did not depend on race or sex.

CONCLUSIONS

Viral suppression was associated with GFR improvements in those with both low CD4 cell counts and impaired baseline renal function, supporting an independent contribution of HIV-1 replication to chronic renal dysfunction in advanced HIV disease. GFR improvement not associated with viral suppression also was observed in subjects with higher CD4 cell counts.

Observations on a cohort of HIV-infected patients undergoing native renal biopsy

AIMS

This study aims to explore the spectrum of renal disease in HIV-infected patients, identify clinical predictors of HIV-associated nephropathy (HIVAN), and investigate the performance of renal biopsy in HIV-infected patients.

METHOD

Of 263 HIV-infected patients with renal disease evaluated between 1995 and 2004, 152 had a renal biopsy, while 111 had not. A group comparison was performed.

RESULTS

The leading biopsy diagnoses were HIVAN (35%), noncollapsing focal segmental glomerulosclerosis (22%), and acute interstitial nephritis (7.9%), amongst over a dozen others. There was a trend of decreasing yearly incidence of HIVAN diagnoses, paralleling the use of antiretroviral therapy. By multivariate logistic regression, CD4 counts >200 cells/mm(3) and higher estimated glomerular filtration rate were strong negative predictors of HIVAN. HIVAN patients were more likely to require dialysis (p < 0.0001) and had worse overall survival (p = 0.02). Younger age and lower estimated glomerular filtration rate were significant predictors of renal biopsy in multivariate regression analysis. More biopsied patients progressed to dialysis (51 vs. 25%, p = 0.001) and death (15 vs. 5.4%, p = 0.001), despite more frequent corticosteroid treatment (29 vs. 3.6%, p = 0.001).

CONCLUSION

These findings may reflect more severe acute and/or chronic disease at the time of biopsy and suggests that earlier renal biopsy may be warranted in HIV-infected patients, especially in light of the changing spectrum of renal disease in this group.

Human immunodeficiency virus-associated nephropathy (HIVAN) in Nigerian children

Human immunodeficiency virus-associated nephropathy (HIVAN) has rarely been reported in African children. In this single-center study, we analyzed ten children diagnosed with HIVAN from January 2000 to October 2006. There were eight boys and two girls, with a male:female ratio of 4:1. Their ages were from 5 months to 15 years (mean 6.8+/-6.2 years), with a peak age of 5-9 years. The presenting complaints included generalized edema (60%) and hypertension (50%). All patients had proteinuria on urine dipstick, with four (40%) at nephrotic range (proteinuria >or=500 mg/dl). Nine (90%) patients were in renal failure, with elevated serum creatinine (6.3-24 mg/dl) and serum urea (70-120 mg/dl). Renal disease was the first manifestation of HIV infection in six patients, whereas the diagnosis was made on autopsy in three. The duration from HIV infection to development of HIVAN ranged from 5 months to 10 years. CD4(+) cell count, done in only three patients due to financial constraints, was below 200/mm(3). The kidneys were hyperechoic on abdominal ultrasound in all patients, and three (30%) showed grossly enlarged kidneys. Histology of renal tissues available by autopsy in three patients showed mainly collapsing focal segmental glomerulosclerosis. Treatments given were angiotensin-converting enzyme (ACE) inhibitors and highly active antiretroviral therapy (HAART) in four and two patients, respectively, and one patient underwent peritoneal dialysis. On outcome analysis, seven (70%) patients died, two were lost to follow-up, and one was alive on HAART therapy at the writing of this article. In conclusion, HIVAN occurs in Nigeria children, and the mortality is very high from uremia.

End-stage renal disease and chronic kidney disease in a cohort of African-American HIV-infected and at-risk HIV-seronegative participants followed between 1988 and 2004

BACKGROUND

HIV-infected African-Americans are at increased risk of end-stage renal disease requiring renal replacement therapy (RRT).

OBJECTIVES

To compare the incidence of RRT in HIV-infected and HIV-seronegative African-Americans and describe temporal trends in RRT and chronic kidney disease (CKD) in HIV infection.

DESIGN

Cohort study in Baltimore including 4509 HIV-infected and 1746 HIV-seronegative African-Americans.

METHODS

Incident RRT was defined by matching participant identifiers with the US Renal Data System; CKD was defined as an estimated glomerular filtration rate < 60 ml/min per 1.73m for >/= 3 months. Standardized incidence ratios (SIR) and 95% confidence intervals (CI) were calculated by indirect adjustment. Risk factors for RRT were assessed by person-time methods and Poisson regression.

RESULTS

RRT was initiated in 24 HIV-seronegative subjects over 13 415 person-years of follow-up (SIR, 2.3; 95% CI, 1.5-3.4), in 51 HIV-infected participants without AIDS over 10 780 person-years (SIR, 6.9; 95% CI, 5.1-9.0), and in 125 participants with AIDS over 9833 person-years. SIR, 16.1; 95% CI, 13.4-19.2). In HIV-infected African-Americans, RRT incidences were 5.8 and 9.7/1000 person-years in the pre-HAART and HAART eras, respectively (adjusted rate ratio 1.2; 95% CI, 0.8-1.9). In supplementary analyses, CKD incidence declined significantly in the HAART era compared with pre-HAART, but the CKD period prevalence increased.

CONCLUSIONS

Nearly 1% of HIV-infected African-Americans initiated RRT annually, a rate that was similar in the HAART and pre-HAART eras. While new cases of CKD decreased, the prevalence of CKD increased in the HAART era, primarily because survival in those with HIV-associated CKD has improved.

Racial differences in end-stage renal disease rates in HIV infection versus diabetes

Few studies have compared the incidence of end-stage renal disease (ESRD) among individuals with the human immunodeficiency virus (HIV) and diabetes. We followed a national sample of 2,015,891 US veterans over a median peroid of 3.7 years for progression to ESRD. The age- and sex-adjusted incidence of ESRD (per 1000 person-years) among HIV-infected black patients was nearly an order of magnitude higher than among HIV-positive white patients, almost twice that of diabetic whites, and similar to that among diabetic blacks. In multivariate Cox proportional hazards analysis, diabetes was associated with an increased risk of ESRD among white patients, but HIV was not. Among black individuals, however, both HIV and diabetes conferred a similar increase in the risk of ESRD (4- to 5-fold increase compared to white individuals without HIV or diabetes). HIV and diabetes carry a similar risk of ESRD among black patients, highlighting the importance of developing strategies to prevent and treat renal disease among HIV-infected black individuals.

Genetic susceptibility, HIV infection, and the kidney

In recent years, the sequencing of mammalian and microbial genomes has provided the opportunity to study how genetic variation in the host and pathogen influence the course of infectious disease. In the case of HIV-1 infection, such studies have led to identification of key viral proteins that determine pathogenicity, immune evasion, or drug resistance. In addition, candidate gene association studies have uncovered a large number of host genetic variants that influence the outcome of infection and some organ-specific complications. HIV-associated nephropathy (HIVAN) is a pathologically distinct complication of HIV infection. Interindividual variability in incidence, skewed ethnic distribution, and familial aggregation of HIVAN with other forms of ESRD have suggested genetic susceptibility as a major contributing factor. This article reviews the host genetic factors that influence the course of HIV-1 infection and discusses murine models that have increased the understanding of HIVAN pathogenesis and demonstrated the role of genetic background on determination of disease.

HIV-1 and HIV-Associated Nephropathy 25 Years Later

Twenty-five years after the first published description of AIDS, HIV-associated nephropathy (HIVAN) remains an important cause of kidney disease in HIV-infected patients. The pathogenesis of HIVAN involves direct HIV infection of the kidney, with both viral and host genetic factors playing an important role. The widespread use of antiretroviral therapy has influenced the epidemiology of HIV-related kidney disease, and the nephrology community should support efforts to improve access to therapy and limit HIV transmission in susceptible minority populations. This article reviews the history of HIV and HIVAN, focusing on advances in the understanding of pathogenesis, epidemiology, and treatment.

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.

HIV-associated nephropathy in the era of antiretroviral therapy

With improved survival in the era of antiretroviral therapy, kidney disease has emerged as an important complication of Human Immunodeficiency Virus (HIV) infection and antiretroviral therapy. The classic kidney disease of HIV infection, HIV-associated nephropathy, occurs almost exclusively in patients of African descent. HIV-associated nephropathy is characterized by collapsing focal segmental glomerulosclerosis with associated tubular dilatation and interstitial inflammation, although the histology may be more subtle in patients receiving antiretroviral therapy. Renal epithelial cells are infected by HIV-1, which results in epithelial cell proliferation and induction of local inflammatory pathways. Even with appropriate therapy, the kidney is a reservoir for HIV-1. Although the widespread introduction of antiretroviral therapy has had a beneficial impact on the epidemiology of HIV-associated nephropathy, the burden of kidney disease is likely to increase as a result of antiretroviral toxicity, reduction in competing mortality risks, and the increasing prevalence of HIV-1 infection in patients at risk for kidney disease.