A Review of the Use of Iloprost, A Synthetic Prostacyclin, in the Prevention of Radiocontrast Nephropathy in Patients Undergoing Coronary Angiography and Intervention

Prevention of Delayed Graft Function in Kidney Transplant Recipients through a Continuous Infusion of the Prostaglandin Analogue Iloprost: A Single-Center Prospective Study

BACKGROUND

Delayed graft function (DGF) is common after kidney transplantation from deceased donors and may significantly affect post-transplant outcomes. This study aimed to evaluate whether an innovative approach, based on the administration of the intravenous prostaglandin analogue iloprost, could be beneficial in reducing the incidence of DGF occurring after kidney transplantation from deceased donors.

METHODS

This prospective, randomized (1:1), placebo-controlled study enrolled all consecutive patients who received a kidney transplant from a deceased donor from January 2000 to December 2012 and who were treated in the peri-transplant period with the prostaglandin analogue iloprost at 0.27 μg/min through an elastomeric pump (treatment group) or with a placebo (control group).

RESULTS

A total of 476 patients were included: DGF was reported in 172 (36.1%) patients in the entire cohort. The multivariate analysis showed that the donor's age > 70 years (OR 2.50, 95% confidence interval (CI): 1.40-3.05, p < 0.001), cold ischemia time > 24 h (OR 2.60, 95% CI: 1.50-4.51, p < 0.001), the donor's acute kidney injury (OR 2.71, 95% CI: 1.61-4.52, p = 0.021) and, above all, the recipient's arterial hypotension (OR 5.06, 95% CI: 2.52-10.1, p < 0.0001) were the strongest risk factors for developing post-transplant DGF. The incidence of DGF was 21.4% in the treatment group and 50.9% in the control group (p < 0.001). Interestingly, among patients who developed DGF, those who received iloprost had a shorter duration of post-transplant DGF (10.5 ± 8.3 vs. 13.4 ± 6.7, days, p = 0.016).

CONCLUSIONS

This study showed that the use of a continuous infusion of iloprost could safely and effectively reduce the incidence of DGF in recipients of deceased-donor kidneys, allowing a better graft functionality as well as a better graft survival.

Comparison of linear versus macrocyclic gadolinium chelates in rat skeletal muscle

OBJECTIVE

We investigated the effects on skeletal muscle of gadolinium based linear and macrocyclic radiocontrast agents applied at experimental intervals using histopathological methods.

METHODS

Thirty-two male Sprague-Dawley rats were included in the study for histopathological analysis. No procedure was performed on the healthy control group. The sham group received 0.1 ml/kg intravenous (IV) saline solution through the tail vein 4 times weekly for 5 weeks. The gadodiamide group received total 2 mmol/kg IV gadodiamide through the tail vein 4 times weekly for 5 weeks. The gadoteric-acid group received 2 mmol/kg IV gadoteric acid through the tail vein 4 times weekly for 5 weeks.

RESULTS

We determined no marked apoptotic myofibrils associated withcaspase-3 expression in these two groups. Furthermore, no calcineurin expression was observed in myofibrils in the two groups. However, quantitative analyses revealed a decrease in muscle-fiber area in the gadodiamide and gadoteric-acid groups compared to the control group (Respectively; p=0.001 and p=0.017).

CONCLUSION

In our experimental study, linear and macrocyclic GBCAs applied at repeated doses played no role in myofibril damage induced by caspase-3 and calcineurin - nuclear factor of activated T-cells in skeletal muscle tissue.

The Influence of Topical Vasodilator-Induced Pharmacologic Delay on Cutaneous Flap Viability and Vascular Remodeling

BACKGROUND

Surgical delay is a well-described technique to improve survival of random and pedicled cutaneous flaps. The aim of this study was to test the topical agents minoxidil and iloprost as agents of pharmacologic delay to induce vascular remodeling and decrease overall flap necrosis as an alternative to surgical delay.

METHODS

Seven groups were studied (n = 8 in each group), including the following: vehicle, iloprost, or minoxidil before treatment only; vehicle, iloprost, or minoxidil before and after treatment; and a standard surgical delay group as a positive control. Surgical flaps (caudally based modified McFarlane myocutaneous skin flaps) were elevated after 14 days of pretreatment, reinset isotopically, and observed at various time points until postoperative day 7. Gross viability, histology, Doppler blood flow, perfusion imaging, tissue oxygenation measurement, and vascular casting were performed for analysis.

RESULTS

Pharmacologic delay with preoperative application of topical minoxidil or iloprost was found to have comparable flap viability when compared to surgical delay. Significantly increased viability in all treatment groups was observed when compared with vehicle. Continued postoperative treatment with topical agents had no effect on flap viability. The mechanism of improved flap viability was inducible increases in flap blood volume and perfusion rather than the acute vasodilatory effects of the topical agents or decreased flap hypoxia.

CONCLUSIONS

Preoperative topical application of the vasodilators minoxidil or iloprost improved flap viability comparably to surgical delay. Noninvasive pharmacologic delay may reduce postoperative complications without the need for an additional operation.

CLINICAL RELEVANCE STATEMENT

Preoperative use of topical vasodilators may lead to improved flap viability without the need for a surgical delay procedure. This study may inform future clinical trials examining utility of preoperative topical vasodilators in flap surgery.

Iloprost in Acute Post-kidney Transplant Atheroembolism: A Case Report of Two Successful Treatments

Cholesterol embolization (CE) is a rare and alarming post-transplant complication, responsible for primary non-function (PNF) or delayed graft function (DGF). Its incidence is expected to rise due to increasingly old donors and recipients and the extended criteria for donation. Therapy with statins and steroids has not been shown to be effective, while agonism of prostaglandin I₂ has been reported to be useful in systemic CE. We report two cases of acute post-transplant CE in which intravenous iloprost (0.05 mg/kg/day) was added to standard statin and steroid therapy. In the first instance, CE was due to embolization from the kidney artery resulting in embolization of the small vessels; after a long DGF and 15 days of iloprost therapy, renal function recovered. The second instance is a case of embolization from the iliac artery of the recipient, where CE manifested as a partial renal infarction. After 5 days of iloprost administration, creatinine levels improved. Iloprost acts on vasodilation and on different inflammatory pathways, improving the anti-inflammatory profile. Post-transplant CE is difficult to diagnose and, if not treated, can lead to loss of function. Iloprost added to standard therapy could be beneficial in accelerating renal function recovery immediately after transplant.

Post-contrast acute kidney injury. Part 2: risk stratification, role of hydration and other prophylactic measures, patients taking metformin and chronic dialysis patients : Recommendations for updated ESUR Contrast Medium Safety Committee guidelines

OBJECTIVES

The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 2011 guidelines on the prevention of post-contrast acute kidney injury (PC-AKI). The results of the literature review and the recommendations based on it, which were used to prepare the new guidelines, are presented in two papers. AREAS COVERED IN PART 2: Topics reviewed include stratification of PC-AKI risk, the need to withdraw nephrotoxic medication, PC-AKI prophylaxis with hydration or drugs, the use of metformin in diabetic patients receiving contrast medium and the need to alter dialysis schedules in patients receiving contrast medium.

KEY POINTS

• In CKD, hydration reduces the PC-AKI risk • Intravenous normal saline and intravenous sodium bicarbonate provide equally effective prophylaxis • No drugs have been consistently shown to reduce the risk of PC-AKI • Stop metformin from the time of contrast medium administration if eGFR < 30 ml/min/1.73 m 2 • Dialysis schedules need not change when intravascular contrast medium is given.

Contrast-Induced Nephropathy: Update on the Use of Crystalloids and Pharmacological Measures

Contrast-induced nephropathy (CIN) is a frequent and severe complication in subjects receiving iodinated contrast media for diagnostic or therapeutic purposes. Several preventive strategies were evaluated in the past. Recent clinical studies and meta-analyses delivered some new aspects on preventive measures used in the past and present. We will discuss all pharmacological and nonpharmacological procedures. Finally, we will suggest individualized recommendations for CIN prevention.

The role of Iloprost on bone edema and osteonecrosis: Safety and clinical results

INTRODUCTION

Iloprost is a commercially available prostaglandin I₂ (PGI₂) analogue that is shown to have antithrombotic, vasodilatative and antiproliferative effects. A number of clinical studies have shown that Iloprost can be effective in the management of bone marrow oedema and the treatment of avascular necrosis. The aim of this manuscript is to present our current understanding on the effect of Iloprost on the treatment of these conditions.

AREAS COVERED

The authors offer a comprehensive review of the existing literature on the experimental and clinical studies analysing the effect of Iloprost on bone, bone marrow oedema and avascular necrosis.

EXPERT OPINION

The available data from the clinical studies suggest that Iloprost has limited effect in advanced stages of avascular necrosis. However, literature suggests that Iloprost administration can be a viable option in the management of bone marrow oedema and early stages of osteonecrosis. Despite these promising results its effect on bone homeostasis needs further elucidation. Moreover, further data on its safety, dosage and efficiency through randomized multicenter studies are desirable in order to reach final conclusions.

High-volume forced diuresis with matched hydration using the RenalGuard System to prevent contrast-induced nephropathy: A meta-analysis of randomized trials

BACKGROUND

Contrast-induced nephropathy (CIN) is a well-recognized complication of coronary angiography that is associated with poor outcomes. Several small randomized controlled trials (RCTs) have recently shown that in patients with chronic kidney disease (CKD), furosemide-induced forced diuresis with matched hydration using the RenalGuard system can prevent its occurrence. However, individual studies have been underpowered and thus cannot show significant differences in major clinical endpoints.

HYPOTHESIS

Forced diuresis with matched hydration using the RenalGuard system improves clinical outcomes in patients undergoing coronary angiography.

METHODS

Scientific databases and websites were searched for relevant RCTs. The pooled risk ratios were calculated using random-effects models. The primary endpoint was CIN, and the secondary endpoints were major adverse clinical events (MACEs) and the need for renal replacement therapy.

RESULTS

Data from 3 trials including 586 patients were analyzed. High-volume forced diuresis with matched hydration using the RenalGuard system decreased risk of CIN by 60% (risk ratio: 0.40, 95% confidence interval: 0.25 to 0.65, P < 0.001), MACE rate by 59%, and the need for renal replacement therapy by 78%, compared with the standard of care.

CONCLUSIONS

In patients with CKD undergoing coronary angiography, high-volume forced diuresis with matched hydration using the RenalGuard system significantly reduces the risk of CIN, MACE rate, and the need for renal replacement therapy. Larger RCTs with sufficient power are needed to confirm these findings.

Allopurinol prophylactic therapy and the prevention of contrast-induced nephropathy in high-risk patients undergoing coronary angiography: A prospective randomized controlled trial

BACKGROUND

Contrast-induced nephropathy (CIN) is considered to be a possibly severe complication of radiography and thus, remains to be the main cause of acute kidney injury (AKI) for inpatients. A clinical trial was executed to measure the preventive effect of allopurinol against CIN in high-risk patients undertaking coronary angiography.

METHODS

Through randomized controlled trial, 140 patients with at minimum two risk factors of CIN, undertaking coronary angiography, were randomly allocated to the allopurinol (n = 70) or control group (n = 70). Those in the allopurinol group received allopurinol (300 mg) a day before their coronary angiography and intravenous hydration for 12 hours before and after their procedure, while members of the control group only received intravenous hydration. Serum creatinine (SCr), blood urea nitrogen (BUN) and uric acid were measured before and 48 hours after the procedure. CIN was defined by a 25% increase in SCr or the concentration of > 0.5 mg/dl, 48 hours after coronary angiography.

RESULTS

CIN was observed in 8 (11.4%) patients in the allopurinol group and 11 (15.7%) patients in the control group. There was no significant difference in the incidence of CIN between the two groups at 48 hours after coronary angiography (P = 0.459). In the allopurinol group, the median SCr concentration decreased non-significantly from 1.16 mg/dl to 1.13 mg/dl, 48 hours after coronary angiography (P = 0.189). In the control group, the median SCr concentration increased significantly from 1.11 mg/dl to 1.2 mg/dl, 48 hours after coronary angiography (P < 0.001).

CONCLUSION

Allopurinol presents no considerable effectiveness over the hydration protocol for development of CIN in high-risk patients.

Predictive value of inflammatory factors on contrast-induced acute kidney injury in patients who underwent an emergency percutaneous coronary intervention

BACKGROUND

Contrast-induced acute kidney injury (CI-AKI) is one of the most serious complications in patients who undergo percutaneous coronary intervention (PCI), especially in those with acute coronary syndrome. It has been shown that inflammation may play an important role in the pathophysiology of CI-AKI.

HYPOTHESIS

Inflammatory factors may play a predominant role in the prediction of CI-AKI in patients who undergo emergency PCI.

METHODS

Patients who underwent emergency PCI from 2013 to 2015 were consecutively enrolled and were divided into CI-AKI and non-CI-AKI groups. Logistic analysis was used to identify the risk factors of CI-AKI. Receiver operator characteristic curve analysis was performed to evaluate the area under the curve (AUC) and to establish the optimal cutoff.

RESULTS

A total of 1061 patients were included, and the CI-AKI rate was 5.47% (58/1061). Logistic analysis showed that the white blood cell (WBC) count (odds ratio [OR]: 1.103, 95% confidence interval [CI]: 1.018-1.195, P = 0.016), neutrophil (N) count (OR: 1.134, 95% CI: 1.045-1.232, P = 0.003), neutrophil to lymphocyte ratio (NLR) (OR: 1.105, 95% CI: 1.044-1.169, P = 0.001), C-reactive protein (CRP) level (OR: 1.006, 95% CI: 1.001-1.011, P = 0.020), high-sensitivity C-reactive protein (hs-CRP) level (OR: 1.099, 95% CI: 1.020-1.184, P = 0.013), and big endothelin-1 (ET-1) level (OR: 4.030, 95% CI: 1.989-8.165, P < 0.001) were all significant predictors for CI-AKI, as was the left ventricular ejection fraction and diuretic administration. The AUC of the big ET-1 level was the highest (0.793, 95% CI: 0.733-0.853), followed by the NLR (0.708, 95% CI: 0.641-0.774), hs-CRP level (0.705, 95% CI: 0.627-0.782), CRP level (0.684, 95% CI: 0.607-0.761), N count (0.655, 95% CI: 0.584-0.726), WBC count (0.620, 95% CI: 0.544-0.695), and erythrocyte sedimentation rate (0.611, 95% CI: 0.527-0.695).

CONCLUSIONS

The WBC count, N count, NLR, CRP level, hs-CRP level, and big ET-1 level are all associated with an increased risk of CI-AKI, and among which, the big ET-1 level, NLR, and the hs-CRP level might have high predictive value for CI-AKI after an emergency PCI.