HIV-associated nephropathy--beneficial effect of zidovudine therapy

Predictors of renal outcome in HIV-associated nephropathy

BACKGROUND

Human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) is an important cause of end-stage renal disease among African American patients. This study was performed to study the epidemiology of HIVAN in a predominantly black African population and the impact of highly active antiretroviral therapy and other factors on the development of end-stage renal disease.

METHODS

We retrospectively identified all patients with HIVAN, defined by biopsy or strict clinical criteria, in 8 clinics in the United Kingdom. Baseline renal function, HIV parameters, renal pathological index of chronic damage, and responses to highly active antiretroviral therapy were analyzed, and factors associated with adverse renal outcome were identified.

RESULTS

From 1998 through 2004, we studied 16,834 patients, 61 of whom had HIVAN. HIVAN prevalence in black patients was 0.93%, and HIVAN incidence in those without renal disease at baseline was 0.61 per 1000 person-years. After a median of 4.2 years, 34 patients (56%) had developed end-stage renal disease. There were no significant differences in renal function and HIV parameters at baseline, time to initiation of highly active antiretroviral therapy, and rates of HIV RNA suppression between the 20 patients who developed end-stage renal disease >3 months after receiving the HIVAN diagnosis and the 23 patients who maintained stable renal function. However, the index of chronic damage score was significantly higher in those who developed end-stage renal disease (P < .001), and an index of chronic damage score >75 was associated with shorter renal survival (P < .001).

CONCLUSIONS

Whereas overall patient survival suggested an important benefit of highly active antiretroviral therapy, no additional renal benefit of early initiation of highly active antiretroviral therapy or viral suppression could be demonstrated in this large cohort of patients with established HIVAN. Severity of chronic kidney damage, as quantified by biopsy, was the strongest predictor of renal outcome.

Effects of immunosuppressive drugs on HIV infection: implications for solid-organ transplantation

With the advent of highly active antiretroviral therapy (HAART), HIV infection has become a chronic disease. Various end-stage organ failures have now become common co-morbidities and are primary causes of mortality in HIV-infected patients. Solid-organ transplantation therefore has been proposed to these patients, as HIV infection is not anymore considered an absolute contraindication. The initial results of organ transplantation in HIV-infected patients are encouraging with no differences in patient and graft survival compared with non-HIV-infected patients. The use of immunosuppressive drug therapy in HIV-infected patients has so far not shown major detrimental effects, and some drugs in combination with HAART have even demonstrated possible beneficial effects for specific HIV settings. Nevertheless, organ transplantation in HIV-infected patients remains a complex intervention, and more studies will be required to clarify open questions such as long-term effects of drug interactions between antiretroviral and immunosuppressive drugs, outcome of recurrent HCV infection in HIV-infected patients, incidence of graft rejection, or long-term graft and patient survival. In this article, we first review the immunological pathogenesis of HIV infection and the rationale for using immunosuppression combined with HAART. We then discuss the most recent results of solid-organ transplantation in HIV-infected patients.

Safety and success of kidney transplantation and concomitant immunosuppression in HIV-positive patients

BACKGROUND

Human immunodeficiency virus-associated nephropathy (HIVAN) has become the third leading cause of end-stage renal disease (ESRD) in African Americans, and is expected to grow exponentially. Highly active antiretroviral therapy (HAART) has significantly prolonged the survival of patients with HIV infection. Despite the growing number of HIV-positive dialysis patients with prolonged life expectancy, kidney transplantation with immunosuppression has been declined because it is considered a waste of scarce donor kidneys due to potential increases in morbidity and mortality.

METHODS

The institutional review board of Drexel University College of Medicine and Hahnemann University Hospital approved this prospective study. The aim was to find out safety and success of kidney transplantation, and the effect of immunosuppression on HIV infection. Forty HIV-positive dialysis patients received kidney transplantation between February 2001 and January 2004. Patient inclusion criteria were maintenance of HAART, plasma HIV-1 RNA of <400 copies/mL, absolute CD4 counts of 200 cells/muL or more. Immunosuppression was basiliximab induction and maintenance with cyclosporine, sirolimus, and steroids. HAART was continued post-transplant. Acute rejections were diagnosed by biopsy and treated with methylprednisolone. Surveillance biopsies were completed at 1, 6, 12, and 24 months, and evaluated for subclinical acute rejection, chronic allograft nephropathy, and HIVAN.

RESULTS

One- and 2-year actuarial patient survival was 85% and 82%, respectively, and graft survival was 75% and 71%, respectively. Plasma HIV-1 RNA remained undetectable, and CD4 counts remained in excess of 400 cells per muL with no evidence of AIDS for up to 2 years.

CONCLUSION

One- and 2-year graft survival is comparable to other high-risk populations receiving kidney transplantation. One- and 2-year patient survival is higher than HIV patients maintained on dialysis. Immunosuppression does not adversely affect HIV recipients maintained on HAART in the short term.

HIV-associated nephropathy: Epidemiology, pathogenesis, and treatment

Initially described in 1984, human immunodeficiency virus-associated nephropathy (HIVAN) has now become a common disease within the HIV-seropositive population. It is a focal segmental glomerulosclerosis causing rapid deterioration of renal function. It is the most common cause of chronic renal disease in HIV patients and occurs almost exclusively in blacks. Through murine and human studies, it is now clear that HIVAN is caused by a direct effect of infection of renal cells by HIV-1 and that the virus actively replicates within renal cells. How the virus causes disease within cells is not yet understood, but there is evidence for factors within infected cells causing both proliferation and apoptosis. Steroids, angiotensin converting enzyme (ACE) inhibitors, and highly active antiretroviral therapy (HAART) have been used for the treatment of HIVAN, with HAART, in particular, showing a dramatic improvement in both the pathologic changes and clinical course of HIVAN.

Human immunodeficiency virus infection and renal failure

Renal manifestations are an important component of HIV disease. Renal disease significantly contributes to morbidity and mortality in patients with HIV. Great progress has been made in identifying specific glomerular lesions and its pathogenesis. Newer antiretroviral agents offer great promise in preventing renal disease and also in patients with established HIVAN. Survival of patients with HIV and ESRD (irrespective of cause) who are receiving RRT continues to improve over the years. Acute reversible renal failure, a preventable complication, is also declining in hospitalized HIV patients. More and more physicians, who in the past were reluctant to care for patients with HIV and renal failure because of grim prognosis, are now becoming familiar with the renal sequelae and are encouraged by recent favorable results. As knowledge about viruses is expanding, the proper use of newer highly effective antiretroviral and other agents in complicated patients should further improve both the survival and quality of life in patients with HIV infection and renal disease.

Treatment of HIV-associated nephropathy

HIV-associated nephropathy (HIVAN) is the most common cause of renal failure in patients infected with type 1 human immunodeficiency virus (HIV-1). The renal prognosis for HIVAN is poor and is typically associated with rapid progression to renal death. We report a patient with biopsy-proven HIVAN who was successfully treated with corticosteroids and review the currently available evidence supporting the specific treatments of this condition. A 34-year-old African-American male with a 2-year history of uncomplicated HIV disease developed progressive azotemia despite treatment with highly active antiretroviral therapy (HAART). He was treated with an uncomplicated 4-month course of prednisone, which improved his serum creatinine from 2.9 to 1.9 mg/dl and decreased his degree of proteinuria from 8 to 2.1 g/day. Two years post-steroid treatment his renal function remains stable. Increasing evidence supports that both ACE inhibitors and HAART are effective in preventing and in some cases of reversing HIVAN induced renal failure. In selected patients who progress despite these measures, a limited course of corticosteroid may achieve long-standing disease remissions. In general, with adequate supervision, corticosteroid therapy appears to be well tolerated and has an acceptable side effect profile. Although persuasive in view of the abysmal natural history of HIVAN, the currently available studies are subject to major methodological limitations. Appropriate randomized controlled trials are urgently required in order to further examine the efficacy, optimal timing, and potential side effects of these treatments.

Hypertension in the HIV-infected patient

HIV infection has reached endemic proportions in many African countries. In addition, HIV infection is a significant cause of renal dysfunction in the United States. HIV patients are at higher risk of developing hypertension at a younger age than the general population. Predisposing factors for developing hypertension include vasculitis in small, medium, and large vessels in the form of leukocytoclastic vasculitis, and aneurysms of the large vessels such as the carotid, femoral, and abdominal aorta with impairment of flow to the renal arteries. A syndrome of acquired glucocorticoid resistance has been described in patients with HIV with hypercortisolism and a lower affinity of the glucocorticoid receptors. The syndrome is characterized clinically by weakness, hypertension or hypotension, and skin pigmentation changes. Acute and chronic renal failure is often associated with HIV infection. The associated dysfunction in water and salt handling often induces hypertension. Finally, atherosclerosis has been described in young adults with HIV infection secondary to receiving highly active antiretroviral therapy.

Cohort study of the treatment of severe HIV-associated nephropathy with corticosteroids

BACKGROUND

Human immunodeficiency virus-associated nephropathy (HIVAN) results in rapidly progressive azotemia. The effectiveness and safety of corticosteroids in the treatment of HIVAN, however, remains controversial.

METHODS

We conducted a retrospective cohort study of patients with biopsy-proven HIVAN and progressive azotemia who were eligible for corticosteroid treatment and who had no clinical or histologic evidence of an alternative cause of acute renal failure. Selected patients were treated with 60 mg of prednisone for one month, followed by a several-month taper.

RESULTS

Twenty-one eligible patients were identified. Thirteen subjects had received corticosteroid treatment, whereas eight had not. The mean serum creatinine was 6.2 and 6.8 mg/dL, respectively (P > 0.05). The relative risk (95% CI) for progressive azotemia with corticosteroid treatment at three months was 0.20 (0.05, 0.76, P < 0.05). This association remained significant despite adjustment in separate logistical regression analyses for baseline creatinine, 24-hour proteinuria, CD4 count, history of intravenous drug use, hepatitis B, and hepatitis C. In an additional logistic regression model, using backward stepwise selection of the previously mentioned covariates, only corticosteroid treatment (P = 0.02) and baseline serum creatinine (P = 0.10) were retained within the model. In the corticosteroid-treated group, the mean level of proteinuria decreased by 5.5 g/24 hour (P = 0.01). On long-term follow-up, there was no significant difference in the incidence of hospitalizations (1 per 2.1 vs. 1 per 2.3 patient months) or of serious infections (1 per 2.6 vs. 1 per 2.3 patient months), but there was a significantly longer duration of hospitalization in the corticosteroid-treated group (3.2 vs. 2 days per patient month). At six months, only one of the non-corticosteroid-treated patients but seven of the corticosteroid-treated group continued to have independent renal function (P = 0.06). Three of the corticosteroid-treated group continued to have independent function at two years of follow-up.

CONCLUSION

A limited course of corticosteroid therapy in selected patients was beneficial and safe. Further research is required for the role of corticosteroids in the treatment of HIVAN.

Clinical response to prolonged corticosteroids in a patient with human immunodeficiency virus-associated nephropathy

Human immunodeficiency virus-associated nephropathy (HIVAN) is characterized by massive proteinuria with rapidly progressive renal failure. We report an adult with HIV infection who developed nephrotic-range proteinuria and acute renal failure requiring hemodialysis. Renal biopsy findings were consistent with HIVAN, exhibiting focal and segmental glomerulosclerosis with dilated microcystic tubules filled with pale eosinophilic material. Institution of corticosteroid therapy was followed by significant improvement in renal function and proteinuria. Corticosteroids were tapered, and the patient experienced worsening of his renal failure and proteinuria. A second course of corticosteroids was again associated with improved renal function. This and other reports suggest that corticosteroids may improve the clinical course of HIVAN.

Clinicopathologic correlates of prednisone treatment of human immunodeficiency virus-associated nephropathy

A 43-year-old man with rapidly evolving renal failure from biopsy-proven human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) and superimposed thrombotic microangiopathic changes was treated with prednisone. His serum creatinine decreased from 7.5 to 3.9 mg/dL, and the 24-hour protein excretion decreased from 15.7 to 6.1 g over 6 to 8 weeks. As the prednisone was tapered, however, the creatinine began to increase, and a repeat biopsy was done to assist with therapeutic decisions. The major differences from the pretreatment biopsy were marked reductions in interstitial lymphocytes and macrophages and absence of thrombotic microangiopathic lesions. This is the first report comparing pretreatment and posttreatment renal biopsy specimens and the findings provide some insight into the means by which prednisone exerts its beneficial clinical effects acutely on this disease.

Captopril and renal survival in patients with human immunodeficiency virus nephropathy

The pathogenesis of human immunodeficiency virus-associated nephropathy (HIVAN) is unknown, but it is characterized by aggressive glomerulosclerosis, tubulopathy, and interstitial inflammation. Currently, no therapy has been proven effective for HIVAN. Angiotensin II has been implicated in the pathogenesis of progressive renal disease in the absence of HIV infection, and treatment with captopril enhances renal survival in patients with diabetic glomerulosclerosis. Serum angiotensin-converting enzyme levels are elevated in patients with HIV infection. We therefore compared the course of 18 patients with biopsy-proven HIVAN (nine treated three times per day with captopril and nine not treated [controls]). The controls were matched to the study patients by age, race, gender, and level of serum creatinine concentration. Renal survival was measured from time of biopsy and treatment with captopril until onset of therapy for end-stage renal disease. Differences between the groups' survival were assessed by Kaplan-Meier and Cox regression analyses. Seven African-American men and two women were in the captopril-treated group, and eight African-American men and one woman were in the control group. No control patient died before the initiation of dialysis. There was no difference between initial mean serum creatinine concentration (3.4 +/- 0.7 mg/dL v 3.7 +/- 0.5 mg/dL), CD4 count (66 +/- 27/microL v 92 +/- 15/microL), or age (41.4 +/- 4.1 years v 36.4 +/- 2.6 years) in the study patients and controls, respectively, but the mean urinary protein to creatinine ratio was higher in the study patients. Renal survival was enhanced in the patients compared with the controls (mean renal survival, 156 +/- 71 days v 37 +/- 5 days, respectively; curves different; P < 0.002, Mantel-Cox log-rank test). Captopril and antiretroviral therapy were associated with enhanced renal survival in a Cox regression analysis, while age, level of serum creatinine, urinary protein to creatinine ratio, and CD4 count were not. These data suggest that treatment with captopril and antiretroviral therapy might be useful in delaying the rapidly progressive renal failure characterizing HIVAN. Captopril might exert its effects by reducing angiotensin II levels, or, alternatively, through decreasing renal tissue expression of growth factors and cytokines or by affecting HIV protease activity and therefore extent of productive renal infection. Such findings must be confirmed by randomized, double-blind, placebo-controlled trials.

Prednisone improves renal function and proteinuria in human immunodeficiency virus-associated nephropathy

PURPOSE

To determine if prednisone ameliorates the course of human immunodeficiency virus-associated nephropathy (HIV-AN).

PATIENTS AND METHODS

Twenty consecutive HIV-infected adults with biopsy-proven HIV-AN (n = 17) or clinical characteristics of HIV-AN (n = 3) with serum creatinine concentrations > 177 mumol/L (2 mg/dL) or proteinuria > 2.0 g/d or both were prospectively evaluated and treated with prednisone at a dose of 60 mg/d for 2 to 11 weeks, followed by a tapering course of prednisone over a 2- to 26-week period. Serum creatinine concentration, 24-hour protein excretion, serum albumin, and steroid-related adverse effects were assessed before and after treatment.

RESULTS

Nineteen patients had serum creatinine concentrations > 117 mumol/L (2 mg/dL). Two of them progressed to end stage renal disease (ESRD) in 4 to 5 weeks. In 17 patients serum creatinine levels decreased from 717 +/- 103 mumol/L (8.1 +/- mg/dL) (mean +/- SE) to 262 +/- 31 mumol/L (3.0 +/- 0.4 mg/dL) (P < 0.001). Five patients relapsed after prednisone was discontinued and were retreated. In these 5 the serum creatinine declined from 728 +/- 107 mumol/L (8.2 +/- 1.2 mg/dL) to 344 +/- 47 mumol/L (3.9 +/- 0.5 mg/dL) (P < 0.01) in response to the second course of prednisone. Twelve of 13 tested patients showed a reduction in 24-hour urinary protein excretion with an average decrement from 9.1 +/- 1.8 g/d to 3.2 +/- 0.6 g/d (P < 0.005). Serum albumin increased from 24.4 +/- 3.6 g/L to 29.3 +/- 2.6 g/L (P = NS) in the 11 patients with paired 24-hour urine collections for whom pre- and post-treatment determinations were available. In one non-azotemic patient with nephrotic syndrome, protein excretion declined from 15.2 to 2.2 g/day and the serum albumin increased from 4.0 g/L to 31.0 g/L. The 20 patients have been followed for a median of 44 weeks (range 8 to 107). Eight ultimately required maintenance dialysis. Eleven died from complications of HIV disease 14 to 107 weeks after institution of prednisone; none was receiving prednisone at the time of death. Seven are alive and free from ESRD a median of 25 weeks (range 8 to 81) from the initiation of prednisone therapy. Six patients developed a total of seven serious infections while receiving prednisone, including Mycobacterium avium-complex infection in 2 and CMV retinitis in 3.

CONCLUSION

Prednisone improves serum creatinine and proteinuria in a substantial proportion of adults with HIV-AN. Corticosteroid-related side effects are not prohibitive. A prospective, randomized controlled trial is required to confirm these preliminary results.

Human immunodeficiency virus-associated glomerulosclerosis

The constellation of nephrotic proteinuria, FSGS, and rapid loss of renal function in a patient infected with HIV-1 has been sufficiently widespread and well documented to justify identification as a specific renal syndrome, HIV-associated nephropathy. The position paper of the National Kidney Foundation-National Institutes of Health task force estimated in 1990 that 10,000 to 15,000 persons will develop renal disease in association with AIDS [94]. Management of these patients is complex, and many will reach ESRD and require dialysis treatment, posing additional care problems. Greater understanding of the pathogenesis of the renal disease should lead to treatments which will forestall the development of HIVAN and possibly other forms of fibrotic renal disease. The ultimate eradication of AIDS will consign this renal syndrome to an interesting footnote in the history of nephrology. Since that time is still far in the future, nephrologists will continue to be faced with the need to diagnose and treat HIV-1-infected patients with renal involvement.

Human immunodeficiency virus-associated nephropathy: current concepts

A distinct form of renal disease has been described in patients at various stages of HIV infection that is becoming increasingly important as a cause of morbidity and mortality. Black race and intravenous drug abuse appear to predispose one to its development. The HIV-associated nephropathy is characterized by nephrotic-range proteinuria, rapid progression to end-stage renal disease, a diffuse sclerosing glomerulopathy with significant tubulo interstitial disease seen on light microscopy, and tubuloreticular inclusions seen via electron microscopy. The entity can be separated from heroin-associated nephropathy. The pathogenesis is unclear. Possibilities include direct invasion of the virus, effects of other viruses, genetic factors, immune factors, and multiple growth factors. Not all patients with HIV infection and renal disease have HIV-associated nephropathy. Because of prognostic and therapeutic implications, it is crucial to differentiate these lesions. Some reports suggest a possible beneficial effect of zidovudine therapy, but more study is required. Patient survival is dependent on the stage of HIV infection. Dialysis therapy does not appear to substantially prolong life in most patients with AIDS and irreversible renal failure. Therefore, a number of ethical issues have arisen that deal with medical futility.