Kidney transplantation in HIV-infected patients

Contemporary issues and new challenges in chronic kidney disease amongst people living with HIV

Chronic kidney disease (CKD) is a comorbidity of major clinical significance amongst people living with HIV (PLWHIV) and is associated with significant morbidity and mortality. The prevalence of CKD is rising, despite the widespread use of antiretroviral therapy (ART) and is increasingly related to prevalent non-infectious comorbidities (NICMs) and antiretroviral toxicity. There are great disparities evident, with the highest prevalence of CKD among PLWHIV seen in the African continent. The aetiology of kidney disease amongst PLWHIV includes HIV-related diseases, such as classic HIV-associated nephropathy or immune complex disease, CKD related to NICMs and CKD from antiretroviral toxicity. CKD, once established, is often relentlessly progressive and can lead to end-stage renal disease (ESRD). Identifying patients with risk factors for CKD, and appropriate screening for the early detection of CKD are vital to improve patient outcomes. Adherence to screening guidelines is variable, and often poor. The progression of CKD may be slowed with certain clinical interventions; however, data derived from studies involving PLWHIV with CKD are sparse and this represent an important area for future research. The control of blood pressure using angiotensin converting enzyme inhibitors and angiotensin receptor blockers, in particular, in the setting of proteinuria, likely slows the progression of CKD among PLWHIV. The cohort of PLWHIV is facing new challenges in regards to polypharmacy, drug-drug interactions and adverse drug reactions. The potential nephrotoxicity of ART is important, particularly as cumulative ART exposure increases as the cohort of PLWHIV ages. The number of PLWHIV with ESRD is increasing. PLWHIV should not be denied access to renal replacement therapy, either dialysis or kidney transplantation, based on their HIV status. Kidney transplantation amongst PLWHIV is successful and associated with an improved prognosis compared to remaining on dialysis. As the cohort of PLWHIV ages, comorbidity increases and CKD becomes more prevalent; models of care need to evolve to meet the new and changing chronic healthcare needs of these patients.

HIV infection with viro-immunological dissociation in a patient with polycystic kidney disease: Candidate for transplantation?

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Autosomal dominant polycystic kidney disease is the most common among inherited cystic kidney diseases.

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Patients with HIV infection are at risk of developing acute kidney injury and chronic kidney disease.

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We provide the first report of HIV infection in a patient with polycystic kidney disease.

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Lymphopenia should not contraindicate kidney transplantation in patients with HIV infection.

Here we describe the case of a HIV-infected patient with polycystic kidney disease and end stage renal diseases not transplantable due to the persistence of a CD4 count <200 notwithstanding a good virological response to highly active antiretroviral therapy and suggest that such limitation to kidney transplantation in such as cases might be bypassed.

A National Study of Outcomes among HIV-Infected Kidney Transplant Recipients

Kidney transplantation is a viable treatment for select patients with HIV and ESRD, but data are lacking regarding long-term outcomes and comparisons with appropriately matched HIV-negative patients. We analyzed data from the Scientific Registry of Transplant Recipients (SRTR; 2002-2011): 510 adult kidney transplant recipients with HIV (median follow-up, 3.8 years) matched 1:10 to HIV-negative controls. Compared with HIV-negative controls, HIV-infected recipients had significantly lower 5-year (75.3% versus 69.2%) and 10-year (54.4% versus 49.8%) post-transplant graft survival (GS) (hazard ratio [HR], 1.37; 95% confidence interval [95% CI], 1.15 to 1.64; P<0.001) that persisted when censoring for death (HR, 1.43; 95% CI, 1.12 to 1.84; P=0.005). However, compared with HIV-negative/hepatitis C virus (HCV)-negative controls, HIV monoinfected recipients had similar 5-year and 10-year GS, whereas HIV/HCV coinfected recipients had worse GS (5-year: 64.0% versus 52.0%, P=0.02; 10-year: 36.2% versus 27.0%, P=0.004 [HR, 1.38; 95% CI, 1.08 to 1.77; P=0.01]). Patient survival (PS) among HIV-infected recipients was 83.5% at 5 years and 51.6% at 10 years and was significantly lower than PS among HIV-negative controls (HR, 1.34; 95% CI, 1.08 to 1.68; P<0.01). However, PS was similar for HIV monoinfected recipients and HIV-negative/HCV-negative controls at both times. HIV/HCV coinfected recipients had worse PS compared with HIV-negative/HCV-infected controls (5-year: 67.0% versus 78.6%, P=0.007; 10-year: 29.3% versus 56.23%, P=0.002 [HR, 1.57; 95% CI, 1.11 to 2.22; P=0.01]). In conclusion, HIV-negative and HIV monoinfected kidney transplant recipients had similar GS and PS, whereas HIV/HCV coinfected recipients had worse outcomes. Although encouraging, these results suggest caution in transplanting coinfected patients.

Immunosuppression regimen and the risk of acute rejection in HIV-infected kidney transplant recipients

BACKGROUND

Kidney transplantation (KT) is the treatment for end-stage renal disease in appropriate HIV-positive individuals. However, acute rejection (AR) rates are over twice those of HIV-negative recipients.

METHODS

To better understand optimal immunosuppression for HIV-positive KT recipients, we studied associations between immunosuppression regimen, AR at 1 year, and survival in 516 HIV-positive and 93,027 HIV-negative adult kidney-only recipients using Scientific Registry of Transplant Recipients data from 2003 to 2011.

RESULTS

Consistent with previous reports, HIV-positive patients had twofold higher risk of AR (adjusted relative risk [aRR], 1.77; 95% confidence interval [CI], 1.45-2.2; P<0.001) than their HIV-negative counterparts as well as a higher risk of graft loss (adjusted hazard ratio, 1.51; 95% CI, 1.18-1.94; P=0.001), but these differences were not seen among patients receiving antithymocyte globulin (ATG) induction (aRR for AR, 1.16; 95% CI, 0.41-3.35, P=0.77; adjusted hazard ratio for graft loss, 1.54; 95% CI, 0.73-3.25; P=0.26). Furthermore, HIV-positive patients receiving ATG induction had a 2.6-fold lower risk of AR (aRR, 0.39; 95% CI, 0.18-0.87; P=0.02) than those receiving no antibody induction. Conversely, HIV-positive patients receiving sirolimus-based therapy had a 2.2-fold higher risk of AR (aRR, 2.15; 95% CI, 1.20-3.86; P=0.01) than those receiving calcineurin inhibitor-based regimens.

CONCLUSION

These findings support a role for ATG induction, and caution against the use of sirolimus-based maintenance therapy, in HIV-positive individuals undergoing KT.

Screening and management of renal disease in human immunodeficiency virus-infected patients in Australia

BACKGROUND

Renal disease has become one of the most important comorbidities observed in the human immunodeficiency virus (HIV)-infected patient cohort. Data are lacking on the current screening and management of renal disease in patients with HIV. We evaluated HIV-infected Australian adults in primary care to determine current practices.

METHODS

This prospective, multicentre observational study included two rounds of data collection; the first was followed by an educational programme. Outcomes included screening for renal disease; management of risk factors for kidney disease and other comorbidities associated with renal disease.

RESULTS

Fifty-three general practitioners participated with 733 patients enrolled. Most were male (94%); almost 40% were 41-50 years of age, and 6% and 84% were receiving antiretroviral therapy. Comorbidities were common; 19% had hypertension, 5% were diabetic, 32% were dyslipidaemic, and 40% were smokers. Estimated glomerular filtration rate was commonly measured in both rounds of data collection (96% vs 95%). Proteinuria was assessed less frequently; this improved after education (48% vs 71%). Almost 10% of patients tested had proteinuria on urinalysis. Of the 45 patients (6%) with renal impairment (estimated glomerular filtration rate <60 mL/min), none was referred for assessment by a renal specialist.

CONCLUSIONS

This large observational study provides important information on renal disease in HIV-infected patients, an area with a paucity of clinical data. Current screening and management practices fall short of suggested guidelines. Failure to refer patients to specialists is a major deficiency. Improvements with education suggest the need to promote awareness of guidelines in primary care doctors.

Kidney transplantation in a patient with HIV disease

Human immunodeficiency virus (HIV) disease was considered an absolute contraindication to kidney transplantation until recently. The main reason was the concern regarding the side effects of immunosuppressive drugs in already immunocompromised patients. Kidney transplantation is considered to be the best form of renal replacement therapy in most patients with kidney failure. Nowadays, many world medical centers are successfully doing kidney transplantation in HIV patients with kidney failure. However, HIV disease is still considered a contraindication to kidney transplantation in most Indian centers. Here, we report a case of a patient with HIV infection and ESRD, who underwent successful kidney transplantation in our center.

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.

Prevalence and clinical characteristics of HIV type 1-infected patients receiving dialysis in Spain: results of a Spanish survey in 2006: GESIDA 48/05 study

End-stage renal diseases (ESRD) are becoming more frequent in HIV-infected patients. In Europe there is little information about HIV-infected patients on dialysis. A cross-sectional multicenter survey in 328 Spanish dialysis units was conducted in 2006. Information from 14,876 patients in dialysis was obtained (81.6% of the Spanish dialysis population). Eighty-one were HIV infected (0.54%; 95% CI, 0.43-0.67), 60 were on hemodialysis, and 21 were on peritoneal dialysis. The mean (range) age was 45 (28-73) years. Seventy-two percent were men and 33% were former drug users. The mean (range) time of HIV infection was 11 (1-27) years and time on dialysis was 4.6 (0.4-25) years. ESRD was due to glomerulonephritis (36%) and diabetes (15%). HIV-associated nephropathy was not reported. Eighty-five percent were on HAART, 76.5% had a CD4 T cell count above 200 cells, and 73% had undetectable viral load. Thirty-nine percent of patients met criteria for inclusion on the renal transplant (RT) waiting list but only 12% were included. Sixty-one percent had HCV coinfection. HCV-coinfected patients had a longer history of HIV, more previous AIDS events, parenteral transmission as the most common risk factor for acquiring HIV infection, and less access to the RT waiting list (p < 0.05). The prevalence of HIV infection in Spanish dialysis units in 2006 was 0.54% HCV coinfection was very frequent (61%) and the percentage of patients included on the Spanish RT waiting list was low (12%).

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.

Mechanisms of Pharmacokinetic and Pharmacodynamic Drug Interactions Associated with Ritonavir-Enhanced Tipranavir

Tipranavir is a nonpeptidic protease inhibitor that has activity against human immunodeficiency virus strains resistant to multiple protease inhibitors. Tipranavir 500 mg is coadministered with ritonavir 200 mg. Tipranavir is metabolized by cytochrome P450 (CYP) 3A and, when combined with ritonavir in vitro, causes inhibition of CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A in addition to induction of glucuronidase and the drug transporter P-glycoprotein. As a result, drug-drug interactions between tipranavir-ritonavir and other coadministered drugs are a concern. In addition to interactions with other antiretrovirals, tipranavir-ritonavir interactions with antifungals, antimycobacterials, oral contraceptives, statins, and antidiarrheals have been specifically evaluated. For other drugs such as antiarrhythmics, antihistamines, ergot derivatives, selective serotonin receptor agonists (or triptans), gastrointestinal motility agents, erectile dysfunction agents, and calcium channel blockers, interactions can be predicted based on studies with other ritonavir-boosted protease inhibitors and what is known about tipranavir-ritonavir CYP and P-glycoprotein utilization. The highly complex nature of drug interactions dictates that cautious prescribing should occur with narrow-therapeutic-index drugs that have not been specifically studied. Thus, the known interaction potential of tipranavir-ritonavir is reported, and in vitro and in vivo data are provided to assist clinicians in predicting interactions not yet studied. As more clinical interaction data are generated, better insight will be gained into the specific mechanisms of interactions with tipranavir-ritonavir.