Hypertension and angiotensin system inhibitors: impact on outcome in sunitinib-treated patients for metastatic renal cell carcinoma.

BACKGROUND: To examine the association between hypertension (HTN), angiotensin system inhibitors (ASI) use and survival outcomes in patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib (SU). METHODS: We retrospectively reviewed all patients with mRCC who received SU as first-line treatment in Gustave Roussy from April 2004 to November 2013. The HTN (either pre-existing or secondary to SU), use of ASI (either before or during SU) were analysed. Overall survival (OS) and progression-free survival (PFS) of different exposures were compared with log-rank test. The associations between exposures and survival outcomes were estimated with hazard ratios (HRs) and 95% confidence interval (CI) through a multivariable Cox model adjusted for age, gender, International mRCC Database Consortium risk group and histology. RESULTS: Among 213 patients with a 3.6-year median follow-up, 134 were hypertensive and 105 were ASI users with a significant association between the two exposures (P < 0.0001). Hypertensive patients have longer OS (median: 41.6 versus 16.4 months, P < 0.0001) and longer PFS (median: 12.9 versus 5.6 months, P < 0.0001) than non-hypertensive patients (n = 79). ASI users (n = 105) had more HTN_PRE compared with those (n = 108) who did not (65% versus 19%, P < 0.001). Multivariable analysis showed that hypertensive patients were significantly associated with OS (P = 0.05) and marginally with PFS (P = 0.06) while ASI intake was significantly associated with better OS [HR = 0.40; 95% CI (0.24-0.66), P < 0.001] and PFS [HR = 0.55 (0.35-0.86), P = 0.009]. The latter remain statistically significantly associated after controlling for the number of metastases. There is no difference on outcome between patients who receive ASI before starting SU and those who received ASI during SU treatment. CONCLUSION: Concomitant use of ASI may significantly improve OS and PFS in mRCC patients receiving SU. HTN is marginally associated with the outcome in these patients.

Acute tubular necrosis associated with mTOR inhibitor therapy: a real entity biopsy-proven.

BACKGROUND: The protein kinase mTOR (mammalian target of rapamycin) is a critical regulator of cellular metabolism, growth, and proliferation. Inhibitors of mTOR have immunosuppressive and anti-cancer effects, but their effects on the progression of kidney disease are not fully understood. Their most common side-effects include stomatitis, rash, dyslipidemia, hyperglycemia, fatigue, and pneumonitis. However, to the best of our knowledge these agents have not been previously reported to cause severe acute kidney injury (AKI). CASE PRESENTATION: We describe four cases of patients with cancer who developed AKI after starting mTOR inhibitor therapy. A kidney biopsy showed acute tubular necrosis (ATN) with prominent tubular dysfunction. Withdrawal of the drug leads to a rapid recovery in two cases. However, a fixed renal dysfunction was noted in the other two cases, one of which will remain dialysis-dependent. Such patients lead to a broad differential diagnosis of AKI including prerenal AKI, ATN, cancer-related GN, and drug-induced acute interstitial nephritis. Accurate history, physical examination, laboratory data, and kidney biopsy are highlighted in establishing the correct diagnosis in such patients. CONCLUSIONS: ATN have not been reported with mTOR inhibitor use. These cases demonstrated a potentially new and serious adverse consequence occurring with the use of an mTOR inhibitor, of which physicians need to be aware.

Management of hypertension in angiogenesis inhibitor-treated patients.

BACKGROUND: Hypertension (HTN) is one of the most frequent side-effects of systemic inhibition of vascular endothelial growth factor (VEGF) signaling. Its incidence and severity are dependent on the type of drugs, dose, and schedule used. The recognition of this side-effect is an important issue because poorly controlled HTN could lead to serious cardiovascular events. On another hand, HTN induced by anti-VEGF agents maybe a predictive factor of oncologic response. Knowledge of this clinical toxicity and/or therapeutic target or novel biomarker of drug activity can aid clinicians choosing the optimal and least toxic regimen suitable for an individual patient. METHODS: A Medline search was carried out using the following criteria: (i) all Medline listings as of 1 January 2000 with abstracts, (ii) English language, and (iii) Humans. The following phrases were used to query the database: ('hypertension', OR 'blood pressure') AND ('anti-VEGF' OR 'VEGF inhibition' OR 'bevacizumab' OR 'sunitinib' OR 'sorafenib' OR 'VEGF Trap'). The references of each article identified were carefully reviewed for additional reference. RESULTS: Lifestyle modification should be encouraged. However, these nonpharmacologic strategies are not always suitable to patients with altered performance status related to metastatic cancer necessitating early drug intervention. Only one randomized study showed a beneficial effect of a calcium channel blocker use to prevent or minimize HTN secondary to antiangiogenic therapy. Nitrates looks as effective in controlling such side-effect. CONCLUSIONS: No clear recommendation for an antihypertensive agent can be made in this context because there is a lack of controlled studies addressing the subject. Blood pressure-lowering drugs should be individualized to the patient's clinical circumstances and angiogenic inhibitors should be withheld only from patients who experienced hypertensive crisis.

Gadolinium-induced nephrotoxicity.

Because of the well-documented risk of acute renal failure with the iodinated contrast media in patients with underlying chronic renal insufficiency, the use of intravenous gadolinium-based contrast media in magnetic resonance imaging for diagnostic and interventional radiology procedures has become a well-established clinical practice in the recent years. Although originally thought to be safe and lack the nephrotoxic effects of iodinated contrast media, gadolinium-based contrast media have recently been reported to induce a usually reversible decrease of glomerular filtration rate in a high-risk population group, especially in patients with altered baseline renal function. Here we present the current experimental and clinical evidence on this new challenge for the nephrologist, gadolinium-induced nephrotoxicity in patients with chronic kidney disease.

[Regression of vena cava tumour thrombus in response to sorafenib]. / Régression d'un thrombus cave néoplasique sous traitement par sorafénib.

Ten percent of patients with kidney cancer have associated vena cava thrombus, which is associated with a high operative morbidity. Up to now, no medical treatment has allowed regression of vena cava tumour thrombus. The authors report the case of a 62-year-old patient with left kidney cancer associated with vena cava tumour thrombus. After surgical resection, the patient relapsed in the form of vena cava thrombus associated with right renal vein thrombus, responsible for renal insufficiency requiring dialysis. Sorafenib therapy allowed regression of the vena cava thrombus, suspension of haemodialysis and local disease control with a follow-up of one year. This case report justifies a review of the place of anti-angiogenic therapy in the treatment of kidney cancer.

[Pharmacokinetics of amprenavir in HIV-1 patients with renal insufficiency]. / Pharmacocinétique de l'amprénavir chez deux patients infectés par le VIH-1 et présentant une insuffisance rénale sévère et terminale.

Amprenavir is an HIV-1 protease inhibitor which is hepatically metabolized (>80%) with a low renal elimination. It has thus been suggested that no dosage adjustment is necessary in patients with renal dysfunction. However, no data are available on the pharmacokinetics of amprenavir in patients with renal insufficiency. We report on the pharmacokinetics of amprenavir in two HIV patients with severe and end-stage renal insufficiency. Amprenavir pharmacokinetics did not differ in our patients as compared with normal renal function subjects. Furthermore, amprenavir was not dialysable (FHD<25%). As a result, the drug may be administered at its normal dose in patients with renal failure, even when severe. In dialysis patients, amprenavir may be administered before or after the session.

COX-2 inhibitors and acute interstitial nephritis: case report and review of the literature.

We report a case of biopsy-proven acute interstitial nephritis (AIN) in a 50-year-old diabetic woman, who had been treated with celecoxib for 4 weeks before presentation. She presented with clinical findings of renal proximal tubulopathy, aseptic leukocyturia and acute renal failure. A kidney biopsy specimen showed AIN with intense tubuli and eosinophilic infiltrate in the interstitium. She recovered normal renal function two weeks after cessation of celecoxib and use of a corticosteroid. A review of the literature yielded eight cases of COX-2 inhibitor-associated AIN with a biopsy-proven diagnosis. Among the reported cases, AIN was diagnosed after an average of 8.3 months of therapy (SD 12 months, range 3 days - 3 years) with 25 mg rofecoxib or 200 mg celecoxib daily. Common symptoms included asthenia, anorexia, nausea and vomiting. The classic triad of fever, rash and eosinophilia was uncommon. Typical laboratory features included hematuria, proteinuria, eosinophilia. Renal failure was common at the time of diagnosis. Mean serum creatinine levels were 0.86 +/- 0.11 mg/dl, 5.66 +/- 3.50 mg/dl and 1.15 +/- 0.24 before treatment, at time of diagnosis and 1 - 2 months after COX-2 inhibitor withdrawal, respectively. Three patients required emergency hemodialysis. After cessation of COX-2 inhibitor treatment, patients recovered completely with a normalized serum creatinine level after one to two months. Management consisted of withdrawal of the COX-2 inhibitor drug and in four patients, corticosteroid therapy was well-tolerated and may have been beneficial.

Is low-dose methotrexate nephrotoxic? Case report and review of the literature.

Methotrexate (MTX) has become the most commonly prescribed disease-modifying anti-rheumatic drug. However, toxicity is an important drawback of MTX therapy and permanent discontinuation of MTX for adverse effects occurs in 1 patient out of 10. Although high-dose MTX is known to be nephrotoxic, data on low-dose MTX renal effects are scanty. We report an insidious and progressive deterioration of renal function during long-term low-dose MTX in a 59-year-old woman. Kidney biopsy revealed advanced kidney fibrosis with extensive interstitial and glomerular fibrosis, and vascular sclerosis. We suggest that patients on low-dose MTX therapy even alone, should be periodically monitored for creatinine levels.

PPAR-gamma-agonists' renal effects.

PPAR-gamma ligands, including thiazolidinediones, have recently become clinically available for treating insulin-resistant diabetes mellitus. Accumulating evidence suggests that these drugs not only significantly improve insulin sensitivity but also may have antiproteinuric effects in genetically obese diabetic rodents and patients with type II diabetes and diabetic nephropathy. Moreover, troglitazone reduced expression of ECM proteins and transforming growth factor-beta in glomeruli from streptozotocin-induced diabetic rats. Many other properties including antiproteinuric, hemodynamic, and antihypertensive effects in insulin-dependent diabetes mellitus suggest that PPAR-gamma ligands might have a direct, beneficial renal effect, independent of their capacity to improve glucose tolerance. Besides their antidiabetic effects, thiazolidinediones have been shown to lower blood pressure in diabetic patients with hypertension and patients with diabetic nephropathy through multiple mechanisms. Several studies showed the efficacy of PPAR-gamma agonists to ameliorate the progression of glomerulosclerosis. The effect is independent of insulin effects and could only be partially due to lipid effects. These renal protective effects of PPAR-gamma agonists suggest that they may provide a novel intervention strategy to prevent vascular and glomerular sclerosis.

[Kidney and glitazones]. / Rein et glitazones.

PPARgamma nuclear receptors are mainly expressed in adipose tissue. However, they are also expressed in renal glomerular tissue and in vascular walls, thus participating through various and complex mechanisms, to glomerular and vascular sclerosis and to nephropathy development and progression. Studies carried out with glitazones, pharmacological agonists of nuclear receptor PPARgamma, in experimental models, either in vitro, or in vivo in animal models, have demonstrated their favourable effects on arterial blood pressure and on prevention and/or progression of diabetic nephropathy. The few clinical studies conducted in type 2 diabetic patients to assess these effects, are also in favor of a beneficial effect of glitazones on blood pressure and nephropathy in these patients. Thus, it appears extremely important and fully justified to conduct specific studies in patients with type 2 diabetes, with the aim to establish and to better characterize these effects in various clinical conditions (antihypertensive effect in treated hypertensive patients according to the class of antihypertensive agents used, prevention of diabetic nephropathy and/or effect on its progression, renal protection, etc.). Some adverse events, although with a low incidence, may be associated with glitazone use (weight gain, peripheral oedema, fluid retention, etc.), and may limit their use in some patients. It is clearly important to better understand the pathophysiological mechanisms of these effects and their possible long term consequences. Finally, it is important to emphasize the easiness to use glitazones in patients with renal insufficiency, without the need to adjust the drug regimen.

MR imaging features of acute bilateral renal cortical necrosis.

Bilateral renal cortical necrosis (BRCN) is an uncommon cause of acute renal failure. Kidney biopsy, arteriography, and contrast-enhanced computed tomography (CT) are usually used to diagnose BRCN. However, these methods can have potentially serious side effects. We report two cases in which magnetic resonance imaging (MRI) evidenced characteristic features of BRCN, which were confirmed by histological findings and arteriography and correlated with clinical evolution. In the first case report, the diagnosis of a massive and complete cortical necrosis variety was suggested on MRI that showed a thin rim of low signal intensity along border of kidneys. It was confirmed on kidney biopsy, and the renal function did not recover. The second case is an incomplete form with cortical patchy areas of low signal intensity. In these two patients, MRI helped to establish an early diagnosis of BRCN with characteristic representative findings, without the potential nephrotoxic effects of iodinated contrast that has to be used in CT and arteriography. Kidney biopsy, besides the risks of complications, provides only a parceled analysis of the renal tissue and therefore does not allow any conclusion as to the extension of cortical necrosis. MRI may be of great help for the diagnosis and follow-up of acute renal cortical necrosis.

[How and when to search for a renal artery atheromatous stenosis in diabetic patients?]. / Quand et comment rechercher une sténose athéromateuse de l'artère rénale chez le diabétique?

The prevalence of RAAS in non-insulin-dependent diabetic patients ranges from 17 to 44%. The prevalence increases exponentially in the presence of several risk factors such as severe arterial hypertension, severe renal insufficiency, macroangiopathy, smoking, and insulin requirement. In diabetic patients, RAAS should be investigated in patients with severe arterial hypertension, repeated pulmonary oedemas, and renal insufficiency without any clear etiology associated with a mild proteinuria and/or with a renal insufficiency secondary to the administration of angiotensin converting enzyme inhibitors or angiotensin II receptors antagonists. Asymmetrical size of the kidneys should also prompt the physician with a suspicion of RAAS. There are several specific criteria, that may confirm the suspicion of a RAAS. Renal arteriography is still the goal standard for diagnosing renal artery stenosis.

Antiviral drug-induced kidney and electrolytes disorders.

HIV patients are at a high risk for nephrotoxicity (HIV-induced nephrotoxicity, HIVAN). As a result, renal insufficiency, tubular dysfunction and renal-related biological disorders are frequently observed in those patients. However, in some cases those defects or anomalies in renal function may be related to antiviral therapies rather than the disease itself. This article reviews the incidence, presentation, prevention and management of antiviral drug-induced renal dysfunction.

Renal effects of PPARalpha-agonists.

Peroxisome proliferator-activated receptor alpha (PPARalpha) is a member of the large nuclear receptor superfamily. Its main role is to activate genes involved in fatty acid oxidation in the liver, heart, kidney and skeletal muscle. While they are mainly used as hypolipidemic agents, PPARalpha agonists may also be postulated to exhibit renoprotective effects. This review summarizes current knowledge regarding the effects of PPARalpha agonists on the kidney.

Anti-viral drugs in continuous ambulatory peritoneal dialysis (CAPD).

The prevalence of HIV-positive subjects in dialysis (hemodialysis and peritoneal dialysis) population varies from 0.13 to 0.36% in italian and french studies, respectively. Most drugs used in HIV therapy are primarily excreted by the kidney. In patients with renal insufficiency, careful dosage adjustment is mandatory to optimize drug exposure and reduce the risk for adverse events. We review the impact of peritoneal dialysis on the pharmacokinetics of antiviral drugs, and discuss on the dosage recommendations needed to achieve efficacy and avoid toxicity in patients with end-stage renal disease undergoing continuous ambulatory peritoneal dialysis (CAPD).

[Pharmacokinetic changes in renal failure]. / Modifications pharmacocinétiques au cours de l'insuffisance rénale.

DRUG PHARMACOKINETICS: One of the first steps in the clinical development of drugs consists in studies of their pharmacokinetics. Dosage and administration interval necessary to ensure secure and efficient plasma levels are derived from the values of pharmacokinetic parameters. Renal disease usually implies multiple pathophysiological modifications that generate alteration in drugs pharmacokinetic profile. Those modifications mainly occur on elimination phase but also to a significant extent on absorption and distribution. PATHOPHYSIOLOGICAL CHANGES: In this article we describe potential alteration in drugs absorption, distribution (volume of distribution, binding to plasma proteins), hepatic or renal metabolism, and parent compound and/or metabolites elimination in patients with renal insufficiency. Furthermore, in patients with end-stage renal disease treated by dialysis, drugs are likely to be removed by extracorporal epuration and dosage and/or interval modifications should thus be applied to treatments in those patients. CLINICAL ASSESSMENT: Pharmacokinetics of drugs should be evaluated in patients with renal failure to determine whereas dosage and/or administration interval should thus be modified to enhance tolerance and pharmacological efficacy. Such studies are obviously necessary for drugs that are mainly excreted unchanged in urine. They should also be performed for drugs that are mainly degraded in the liver with emphasis on metabolites pharmacokinetics.

[Kimura's disease: an unrecognized cause of adult-onset nephrotic syndrome with minimal change disease]. / La maladie de Kimura: une cause méconnue de syndrome néphrotique à lésions glomérulaires minimes de l'adulte.

Kimura's disease (KD) is an angiolymphoid proliferative disorder of soft tissue with eosinophilia, with a predilection for head and neck regions in young Oriental men. Kidney disease is thought to be rare in KD. About a case of adult-onset nephrotic syndrome with minimal change disease, we comment Kimura's disease and its associated kidney damage. Kimura disease should be suspected and included in the diagnosis of adult-onset nephrotic syndrome with minimal change disease.

[Myeloproliferative neoplasms related glomerulopathy]. / Glomérulopathies associées aux syndromes myéloprolifératifs.

Myeloproliferative neoplasms (MPNs, formerly called chronic myeloproliferative disorders) are clonal hematopoietic stem cell disorders characterized by the expansion of one or more of the myeloid lineages, including polymorphonuclear, erythroid, megakaryocytic, and mastocytic. The major complications of MPN are transformation into acute myeloid leukemia (occurring particularly in chronic myelogenous leukemia) and thrombotic and hemorrhagic events (most commonly observed in polycythemia vera and essential thrombocythemia). Renal involvement by MPN is infrequent. MPN-related glomerulopathy enlarges the spectrum of glomerular diseases associated with haematological neoplasms. MPN-related glomerulopathy is an under recognized late renal complication of MPN with poor prognosis. It is characterized clinically by heavy proteinuria and renal insufficiency. The histologic features of MPN-related glomerulopathy include variable degree of mesangial sclerosis and hypercellularity, segmental sclerosis, features of chronic thrombotic microangiopathy, and intracapillary hematopoietic cell infiltration. PDGF and TGFß likely have a crucial role in the pathogenesis of MPN-related glomerulopathy. Furthermore, aggregation of circulating hematopoietic cells within glomerular capillaries could potentially result in endothelial injury and morphologic changes resembling chronic thrombotic microangiopathy. Greater awareness of this entity is needed to define diagnosis and possible therapies.