The impact of NSF on the care of patients with kidney disease

Breakthrough Hypersensitivity Reactions to Gadolinium-based Contrast Agents and Strategies to Decrease Subsequent Reaction Rates: A Systematic Review and Meta-Analysis

Background Hypersensitivity reactions to gadolinium-based contrast agents (GBCAs) that occur despite corticosteroid premedication (breakthrough reactions) are not well understood. Purpose To determine the GBCA breakthrough reaction rate overall and according to GBCA class and to determine the effect of using an alternative GBCA or allergy skin testing on the risk of a breakthrough reaction. Materials and Methods In this systematic review and meta-analysis, MEDLINE (from 1946 to 2019), Embase (from 1947 to 2019), and the Cochrane Central Register of Controlled Trials (2019 only) were searched for patients with a breakthrough reaction to a GBCA who were undergoing repeat GBCA administration. Breakthrough reaction rates were determined with random-effects modeling and meta-regression. Secondary analyses of GBCA class, switching to an alternative GBCA, and allergy skin testing were assessed. Quality Assessment of Diagnostic Accuracy Studies 2 was used to determine risk of bias and applicability. Percentages are meta-regression results and do not directly reflect raw data. Results Of the 148 identified studies, 23 were included, encompassing 120 patients and 130 GBCA administrations. The overall breakthrough reaction rate was 39% (95% confidence interval [CI]: 30%, 49%; 37 of 103 administrations). Breakthrough reaction rates for macrocyclic (36%; 95% CI: 25%, 48%; 23 of 64 administrations) and protein-binding linear (31%; 95% CI: 1%, 94%; [one of seven administrations) GBCAs did not differ (P = .90). There were insufficient analyzable data for gadodiamide, gadoversetamide, and gadopentetate. Hypersensitivity reaction rate after switching GBCAs was 50% (95% CI: 21%, 79%; three of nine administrations) with and 71% (95% CI: 21%, 95%; four of five administrations) without corticosteroid premedication, which did not differ (P = .82 and P = .17, respectively) from the observed rate when using corticosteroid premedication and the same GBCA (36%; 95% CI: 26%, 48%; 37 of 84 administrations). Hypersensitivity reaction rate after allergy skin testing (17%; 95% CI: 7%, 29%; zero of 21 studies) did not differ when compared with use of the same agent with corticosteroid premedication (P = .10). Meta-analysis limitations were the small number of patients and the high risk of bias. Conclusion Patients with a prior hypersensitivity reaction to a gadolinium-based contrast agent (GBCA) often had breakthrough reactions. The effect of switching to an alternative GBCA or using allergy skin testing to decrease reaction risk lacked enough available data for meaningful comparisons. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Prince in this issue.

Updated Clinical Practice Guideline on Use of Gadolinium-Based Contrast Agents in Kidney Disease Issued by the Canadian Association of Radiologists

In 2017, the Canadian Association of Radiologists issued a clinical practice guideline (CPG) regarding the use of gadolinium-based contrast agents (GBCAs) in patients with acute kidney injury (AKI), chronic kidney disease (CKD), or on dialysis due to mounting evidence indicating that nephrogenic systemic fibrosis (NSF) occurs with extreme rarity or not at all when using Group II GBCAs or the Group III GBCA gadoxetic acid (compared to first generation Group I linear GBCAs). One of the goals of the work group was to re-evaluate the CPG after 24 months to determine the effect of more liberal use of GBCA on reported cases of NSF in patients with AKI, CKD Stage 4 or 5 (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m2), or those that are dialysis-dependent. A comprehensive review of the literature was conducted by a subcommittee of the initial CPG panel between the dates of January 1, 2017-December 31, 2018 to identify new unconfounded cases of NSF linked to Group II or Group III GBCAs and an updated CPG developed. To our knowledge, when using a Group II or Group III GBCA between 2017-2018, only a single unconfounded case report of a fibrosing dermopathy has been reported in a patient who received gadobenate dimeglumine with Stage 2 CKD. No other unconfounded cases of NSF have been reported with Group II or III agents in during this timeframe. The subcommittee concluded that the main recommendations from the 2017 CPG should remain unaltered, but agreed that screening for renal disease in the outpatient setting is no longer justifiable, cost-effective or recommended. Patients on hemodialysis (HD) should, however, be identified prior to GBCA administration to arrange timely HD to optimize gadolinium clearance, although there remains no evidence that HD reduces the risk of NSF. When administering Group II or III GBCAs to patients with AKI, on dialysis or with severe CKD, informed consent relating to NSF is also no longer explicitly recommended.

Magnetic resonance imaging contrast enhancement in vitro and in vivo by octanuclear iron-oxo cluster-based agents

A water-soluble octanuclear cluster, [Fe₈], was studied with regard to its properties as a potential contrast enhancing agent in magnetic resonance imaging (MRI) in magnetic fields of 1.3, 7.2 and 11.9 T and was shown to have transverse relaxivities r₂ = 4.01, 10.09 and 15.83 mM s^-1, respectively. A related hydrophobic [Fe₈] cluster conjugated with 5 kDa hyaluronic acid (HA) was characterized by ⁵⁷Fe-Mössbauer and MALDI-TOF mass spectroscopy, and was evaluated in aqueous solutions in vitro with regard to its contrast enhancing properties [r₂ = 3.65 mM s^-1 (1.3 T), 26.20 mM s^-1 (7.2 T) and 52.18 mM s^-1 (11.9 T)], its in vitro cellular cytotoxicity towards A-549 cells and COS-7 cells and its in vivo enhancement of T₂-weighted images (4.7 T) of a human breast cancer xenografted on a nude mouse. The physiologically compatible [Fe₈]-HA conjugate was i.v. injected to the tumor-bearing mouse, resulting in observable, heterogeneous signal change within the tumor, evident 15 min after injection and persisting for approximately 30 min. Both molecular [Fe₈] and its HA-conjugate show a strong magnetic field dependence on r₂, rendering them promising platforms for the further development of T₂ MRI contrast agents in high and ultrahigh magnetic fields.

Gadolinium-Based Contrast Agents in Kidney Disease: A Comprehensive Review and Clinical Practice Guideline Issued by the Canadian Association of Radiologists

PURPOSE OF REVIEW

Use of gadolinium-based contrast agents (GBCA) in renal impairment is controversial, with physician and patient apprehension in acute kidney injury (AKI), chronic kidney disease (CKD), and dialysis because of concerns regarding nephrogenic systemic fibrosis (NSF). The position that GBCA are absolutely contraindicated in AKI, category G4 and G5 CKD (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m2), and dialysis-dependent patients is outdated and may limit access to clinically necessary contrast-enhanced magnetic resonance imaging (MRI) examinations. This review and clinical practice guideline addresses the discrepancy between existing Canadian guidelines regarding use of GBCA in renal impairment and NSF.

SOURCES OF INFORMATION

Published literature (including clinical trials, retrospective cohort series, review articles, and case reports), online registries, and direct manufacturer databases were searched for reported cases of NSF by class and specific GBCA and exposed patient population.

METHODS

A comprehensive review was conducted identifying cases of NSF and their association to class of GBCA, specific GBCA used, patient, and dose (when this information was available). Based on the available literature, consensus guidelines were developed by an expert panel of radiologists and nephrologists.

KEY FINDINGS

In patients with category G2 or G3 CKD (eGFR ≥ 30 and < 60 mL/min/1.73 m2), administration of standard doses of GBCA is safe and no additional precautions are necessary. In patients with AKI, with category G4 or G5 CKD (eGFR < 30 mL/min/1.73 m2) or on dialysis, administration of GBCA should be considered individually and alternative imaging modalities utilized whenever possible. If GBCA are necessary, newer GBCA may be administered with patient consent obtained by a physician (or their delegate) citing an exceedingly low risk (much less than 1%) of developing NSF. Standard GBCA dosing should be used; half or quarter dosing is not recommended and repeat injections should be avoided. Dialysis-dependent patients should receive dialysis; however, initiating dialysis or switching from peritoneal to hemodialysis to reduce the risk of NSF is unproven. Use of a macrocyclic ionic instead of macrocyclic nonionic GBCA or macrocyclic instead of newer linear GBCA to further prevent NSF is unproven. Gadopentetate dimeglumine, gadodiamide, and gadoversetamide remain absolutely contraindicated in patients with AKI, those with category G4 or G5 CKD, or those on dialysis. The panel agreed that screening for renal disease is important but less critical when using macrocyclic and newer linear GBCA. Monitoring for and reporting of potential cases of NSF in patients with AKI or CKD who have received GBCA is recommended.

LIMITATIONS

Limited available literature (number of injections and use in renal impairment) regarding the use of gadoxetate disodium. Limited, but growing and generally high-quality, number of clinical trials evaluating GBCA administration in renal impairment. Limited data regarding the topic of Gadolinium deposition in the brain, particularly as it related to patients with renal impairment.

IMPLICATIONS

In patients with AKI and category G4 and G5 CKD (eGFR < 30 mL/min/1.73 m2) and in dialysis-dependent patients who require GBCA-enhanced MRI, GBCA can be administered with exceedingly low risk of causing NSF when using macrocyclic agents and newer linear agents at routine doses.

Gadolinium-Based Contrast Agents in Kidney Disease: Comprehensive Review and Clinical Practice Guideline Issued by the Canadian Association of Radiologists

Use of gadolinium-based contrast agents (GBCAs) in renal impairment is controversial, with physician and patient apprehension in acute kidney injury (AKI), chronic kidney disease (CKD), and dialysis because of concerns regarding nephrogenic systemic fibrosis (NSF). The position that GBCAs are absolutely contraindicated in AKI, CKD stage 4 or 5 (estimated glomerular filtration rate [eGFR] <30 mL/min/1.73 m²) and dialysis-dependent patients is outdated, and may limit access to clinically necessary contrast-enhanced MRI examinations. Following a comprehensive review of the literature and reported NSF cases to date, a committee of radiologists and nephrologists developed clinical practice guidelines to assist physicians in making decisions regarding GBCA administrations. In patients with mild-to-moderate CKD (eGFR ≥30 and <60 mL/min/1.73 m²), administration of standard doses of GBCA is safe and no additional precautions are necessary. In patients with AKI, with severe CKD (eGFR <30 mL/min/1.73 m²), or on dialysis, administration of GBCAs should be considered individually and alternative imaging modalities utilized whenever possible. If GBCAs are necessary, newer GBCAs may be administered with patient consent obtained by a physician (or their delegate), citing an exceedingly low risk (much less than 1%) of developing NSF. Standard GBCA dosing should be used; half or quarter dosing is not recommended and repeat injections should be avoided. Dialysis-dependent patients should receive dialysis; however, initiating dialysis or switching from peritoneal to hemodialysis to reduce the risk of NSF is unproven. Use of a macrocyclic ionic instead of macrocyclic nonionic GBCA or macrocyclic instead of newer linear GBCA to further prevent NSF is unproven. Gadopentetate dimeglumine, gadodiamide, and gadoversetamide remain absolutely contraindicated in patients with AKI, with stage 4 or 5 CKD, or on dialysis. The panel agreed that screening for renal disease is important but less critical when using macrocyclic and newer linear GBCAs. Monitoring for and reporting of potential cases of NSF in patients with AKI or CKD who have received GBCAs is recommended.

Scleroderma Mimickers

Cutaneous fibrosing disorders encompass a diverse array of diseases united by the presence of varying degrees of dermal sclerosis. The quality and distribution of skin involvement, presence or absence of systemic complications and unique associated laboratory abnormalities often help to distinguish between these diseases. It is imperative that an effort is made to accurately differentiate between scleroderma and its mimics, in order to guide long-term management and facilitate implementation of the appropriate treatment modality where indicated.

Magnetic resonance imaging of the cirrhotic liver: An update

Noninvasive imaging has become the standard for hepatocellular carcinoma (HCC) diagnosis in cirrhotic livers. In this review paper, we go over the basics of MR imaging in cirrhotic livers and describe the imaging appearance of a spectrum of hepatic nodules marking the progression from regenerative nodules to low- and high-grade dysplastic nodules, and ultimately to HCCs. We detail and illustrate the typical imaging appearances of different types of HCC including focal, multi-focal, massive, diffuse/infiltrative, and intra-hepatic metastases; with emphasis on the diagnostic value of MR in imaging these lesions. We also shed some light on liver imaging reporting and data system, and the role of different magnetic resonance imaging (MRI) contrast agents and future MRI techniques including the use of advanced MR pulse sequences and utilization of hepatocyte-specific MRI contrast agents, and how they might contribute to improving the diagnostic performance of MRI in early stage HCC diagnosis.

Nephrogenic systemic fibrosis

OBJECTIVE

The purpose of this article is to discuss nephrogenic systemic fibrosis (NSF) in detail regarding its history, possible pathophysiology, clinical and pathologic presentations, diagnosis, and implications for the radiology community.

CONCLUSION

NSF is a potentially lethal disorder that occurs in patients with reduced kidney function. Current evidence suggests a strong association with gadolinium-based contrast agents--mostly used in MRI--in this patient group. This has urged the radiology community to emphasize careful screening for the presence of renal dysfunction among patients for whom gadolinium-enhanced MRI is contemplated. Appropriate selection of gadolinium-based contrast agent type, avoidance of nonstandard dosage, patient education, and informed consent have been recommended by authorities.

Diagnostic accuracy of diffusion-weighted MRI for identifying hepatocellular carcinoma with liver explant correlation

BACKGROUND

The goal of this study was to use liver explant correlation to assess the diagnostic accuracy of diffusion-weighted (DW)-MRI for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Thirty-seven patients were retrospectively identified who had undergone liver transplantation and had preoperative, respiratory-triggered, single-shot echo-planar DW-MRI. Two independent blinded observers evaluated the DW-MRI images for HCC and comparison was made with the explanted specimens.

RESULTS

By pathology, 29 HCCs (mean largest diameter 2.0 cm; range 0.7-4.0 cm) were identified in 20 patients. Sensitivity and specificity for reader 1 were 55 and 92%, and for reader 2 were 45 and 100%. There was 'substantial' inter-observer agreement (kappa = 0.64).

CONCLUSION

DW-MR is not sensitive enough for HCC to be used as a stand-alone sequence, although its high specificity suggests that it is likely valuable as a component of a liver MRI protocol.

Synthesis of NanoQ, a copper-based contrast agent for high-resolution magnetic resonance imaging characterization of human thrombus

A new site-targeted molecular imaging contrast agent based on a nanocolloidal suspension of lipid-encapsulated, organically soluble divalent copper has been developed. Concentrating a high payload of divalent copper ions per nanoparticle, this agent provides a high per-particle r1 relaxivity, allowing sensitive detection in T1-weighted magnetic resonance imaging when targeted to fibrin clots in vitro. The particle also exhibits a defined clearance and safety profile in vivo.

Nephrogenic systemic fibrosis and gadolinium-based contrast agents

The strong association between nephrogenic systemic fibrosis (NSF) and exposure to gadolinium-based contrast agents (GBCAs) has greatly affected the care of patients with kidney disease. NSF has been reported in patients with ESRD, CKD, and acute kidney injury (AKI). The majority of cases have occurred in patients with ESRD, but about 20% have been reported in patients with AKI or CKD stages 4 and 5. There is also a risk difference among GBCAs, with the Food and Drug Administration contraindicating 3 linear agents in patients at risk. Given the significant morbidity and mortality of NSF, it is imperative to identify individuals at risk. Although there are no data to support a role for hemodialysis (HD) in reducing the risk for NSF after administration of GBCAs, immediate HD is still recommended within 2 hours. Patients maintained on peritoneal dialysis seem to be at high risk and immediate HD is also recommended. However, this is not the current recommendation for CKD stages 4 and 5, especially with suspected lower risk of noncontraindicated agents. Individualized assessment is important and especially in those patients close to dialysis initiation. Instituting policies is important to address the imaging needs of patients with CKD and AKI while ensuring a balance between benefits and risks.

Assessment of the diagnostic accuracy of T2*-weighted MR imaging for identifying hepatocellular carcinoma with liver explant correlation

BACKGROUND

T2*-weighted MRI may represent a novel method for identifying hepatocellular carcinoma (HCC). The goal of this study was to assess the diagnostic accuracy of T2*-weighted MRI for HCC with liver explant correlation.

MATERIALS AND METHODS

A retrospective review identified 25 patients who had undergone liver transplantation with pre-operative T2*-weighted MRI. All patients had Child's-Pugh A (9), B (9), or C (7) liver disease with 13 transplanted for liver dysfunction and 12 for HCC. The T2*-weighted images were interpreted by 2 blinded, independent observers and the results compared with the explanted specimens. Sensitivity and specificity of T2*-weighted MRI for the identification of HCC was assessed.

RESULTS

By pathology, 16 HCC (mean largest diameter 2.1 cm; range 0.9-3.6 cm) were identified in 14 patients. Reader 1 had a sensitivity of 69% (95% confidence interval 41-88%) and a specificity of 100% (68-100%). Reader 2 had a sensitivity of 56% (31-79%) and a specificity of 100% (68-100%). There was a very good inter-observer agreement (kappa=0.84).

CONCLUSION

T2*-weighted MRI had a moderate sensitivity for identifying HCC but had an excellent specificity. A T2*-weighted MR sequence may be a useful component of a liver MRI protocol due to its high specificity for HCC, and may be particularly useful in patients unable to undergo gadolinium enhanced MRI.

Nephrogenic systemic fibrosis

Nephrogenic systemic fibrosis, initially called nephrogenic fibrosing dermopathy, has been strongly linked to exposure to gadolinium-based contrast media used in magnetic resonance imaging in patients with renal insufficiency. This review discusses recent advances in our understanding of the pathophysiology and clinical approach to patients with chronic kidney disease who require diagnostic imaging with gadolinium-based contrast media.

Renal transplantation for nephrogenic systemic fibrosis: a case report and review of the literature

Nephrogenic systemic fibrosis (NSF) is a rare fibrosing disorder described among patients with renal disease. Currently, no standard therapy exists, although therapeutic modalities have included plasmapheresis, extracorporeal photopheresis, sodium thiosulphate, imatinib and renal transplantation. We describe a patient with NSF who was physically debilitated and underwent renal transplantation. After transplantation, the patient's lesions improved clinically, and the patient was ambulatory. Despite developing worsening renal function, her lesions remained unchanged. We conclude that renal transplantation improves symptoms of NSF, and believe that in patients with NSF, careful consideration should be made for early renal transplantation.

Time-resolved lower extremity MRA with temporal interpolation and stochastic spiral trajectories: preliminary clinical experience

PURPOSE

To assess added value of a new time-resolved technique with temporal interpolation and stochastic spiral trajectory through k-space and parallel imaging (TR-MRA) to conventional bolus chase MRA (BC-MRA) for infragenual peripheral artery evaluation.

MATERIALS AND METHODS

An institutional review board-approved retrospective review of peripheral arterial disease patients was performed. Infragenual TR-MRA and BC-MRA were performed in 26 patients over four months. Two readers individually assessed image quality, diagnostic confidence, and stenosis severity and length in 13 defined below knee segments, first with BC-MRA alone, and then with a combined BC-MRA and TR-MRA reading (BC+TR-MRA). Perceived contribution of TR-MRA was rated by each reader. The reference standard was a consensus reading of both sequences. Catheter angiographic (CA) correlation was available in 6 patients.

RESULTS

A total of 646 infragenual segments in 51 extremities were evaluated. Image quality and diagnostic confidence were superior for BC+TR-MRA compared with BC-MRA alone (P < 0.001). Adding TR-MRA improved sensitivity (85.7% versus 80.7%; P < 0.05) and diagnostic accuracy (88.1% versus 85.4%; P < 0.05) for hemodynamically significant stenosis. Venous contamination (0% versus 13.1% segments) and motion (0.9% versus 8.0%) were decreased for BC+TR-MRA versus BC-MRA alone, P < 0.01. For BC+TR-MRA, TR-MRA was rated more useful than BC-MRA in 30/51 legs (58.8%). TR-MRA identified retrograde flow in 5 segments. Where available, there was high concordance between CA and BC+TR-MRA (91.6%) for stenosis.

CONCLUSION

Adding TR-MRA with temporal interpolation and stochastic spiral trajectories to bolus chase MRA improves image quality, diagnostic confidence and accuracy. It provides hemodynamic information and minimizes venous contamination and patient motion.

Removal of gadolinium by dialysis: review of different strategies and techniques

Nephrogenic systemic fibrosis (NSF) has been related to the administration of gadolinium-based contrast agents for magnetic resonance imaging studies in patients with kidney disease. After reviewing the pathophysiology of NSF, we discuss the possible factors contributing to the toxicity of gadolinium in susceptible patients, including the excessive amounts of intravenous iron and erythropoietin as well as the inflammatory states commonly seen in patients treated with hemodialysis. Since free gadolinium is the most accepted risk factor for NSF, we provide some suggestions to improve clearance of both free and chelated gadolinium using different dialysis strategies and techniques. J. Magn. Reson. Imaging 2009;30:1347-1349. (c) 2009 Wiley-Liss, Inc.

Prevalence of NSF following intravenous gadolinium-contrast media administration in dialysis patients with endstage renal disease

PURPOSE

To evaluate the prevalence of nephrogenic systemic fibrosis (NSF) in a patient population being at highest risk for developing this disease and to evaluate possible risk factors.

MATERIALS AND METHODS

The radiological records of 552 patients with ESRD being on hemodialysis (HD) or peritoneal dialysis (PD) were retrospectively reviewed to identify whether the patients underwent MR-examinations with or without intravenous administration of GBCA. In case of exposure to GBCA, the number of contrast injections, the benchmark and the cumulative doses of GBCA, and possible cofactors regarding pathogenesis of NSF were recorded. Diagnosis of NSF was confirmed either by deep skin biopsy or by review of medical and histopathological records. Data of NSF patients were compared with data of dialysis patients who did not develop NSF after MR-examinations.

RESULTS

146 dialysis patients underwent MRI without i.v.-administration of GBCA. No case of NSF was observed in this patient population. 195/552 patients proved to have a total number of 325 well-documented exposures to GBCA. Seven different types of GBCA were used during these MR-examinations. NSF prevalence rate was 1.6%. One patient died of NSF. Three different types of GBCA were involved in 6 NSF cases. 4/6 proved to be confounded cases. The cumulative dose of GBCA, history of thrombosis, recent surgery, and the combination of HD and PD proved to be significant cofactors for the development of NSF (p<.05). No significant difference regarding residual renal clearance (p=.898) and residual urine volume (p=.083) was found between NSF and non-NSF patients.

CONCLUSION

The prevalence of NSF proved to be much lower in this high risk patient group being exposed to GBCA compared to the literature. NSF was not observed in ESRD patients undergoing MRI without administration of GBCA. Our data support a positive association between cumulative dose of GBCA and development of NSF. No positive association was found between residual renal clearance and residual urine volume and NSF.

Sensitive and efficient detection of thrombus with fibrin-specific manganese nanocolloids

In this work, we report novel fibrin targeted "soft-type" manganese-based contrast agents for MRI with the potential to noninvasively image intravascular thrombus which could warrant aggressive medical intervention to preclude subsequent myocardial infarction or stroke.

Acute kidney injury in the intensive care unit

Acute kidney injury (AKI) is common among critically ill patients and results in increased mortality in this population. This review focuses on the diagnosis and management of AKI. The authors first explore new aspects of diagnosis, including new criteria that take into account even modest changes in renal function, and the development of novel biomarkers to allow earlier identification and better differential diagnosis of AKI. The authors also explore the available data on choice of dialysis modality and dialysis dose for the treatment of AKI, as well as the breakthrough development of the bioartificial kidney. Last, the authors review co-interventions that may have relevance to prognosis of AKI, such as intensive insulin therapy and the use of erythropoietin.

Nanomedicine: perspective and promises with ligand-directed molecular imaging

Molecular imaging and targeted drug delivery play an important role toward personalized medicine, which is the future of patient management. Of late, nanoparticle-based molecular imaging has emerged as an interdisciplinary area, which shows promises to understand the components, processes, dynamics and therapies of a disease at a molecular level. The unprecedented potential of nanoplatforms for early detection, diagnosis and personalized treatment of diseases, have found application in every biomedical imaging modality. Biological and biophysical barriers are overcome by the integration of targeting ligands, imaging agents and therapeutics into the nanoplatform which allow for theranostic applications. In this article, we have discussed the opportunities and potential of targeted molecular imaging with various modalities putting a particular emphasis on perfluorocarbon nanoemulsion-based platform technology.

Tailored supplemental screening for breast cancer: what now and what next?

OBJECTIVE

This article reviews breast cancer risk assessment and the rationale for current screening guidelines, including when to consider using supplemental screening with MRI or sonography in addition to mammography, and discusses other emerging technologies. Radiologists can help identify women who may benefit from supplemental screening and can help to recommend when and which techniques to perform for this additional screening.

CONCLUSION

Mammography remains the mainstay of breast cancer screening. Mammography should be performed as digital imaging when possible in women with dense breasts. In women at high risk, particularly if they also have dense breasts, annual MRI is recommended, although further validation of outcomes is needed. In intermediate-risk women with dense breasts, especially those with other risk factors, and in high-risk women with dense breasts who are unable to tolerate MRI, supplemental sonography screening is an option at facilities with availability of qualified personnel. Developing technologies are not appropriate for screening at this time, although further study is encouraged.

Skin problems in chronic kidney disease

Skin disorders associated with chronic kidney disease (CKD) can markedly affect a patient's quality of life and can negatively impact their mental and physical health. Uremic pruritus, which is frequently encountered in patients with CKD, is considered to be an inflammatory systemic disease rather than a local skin disorder. Biomarkers of inflammation are increased in patients with uremic pruritus and an imbalance of the endogenous opioidergic system might be involved in the complex pathogenesis of the disease. Treatment options for uremic pruritus include emollients, topical capsaicin cream, ultraviolet B phototherapy, gabapentin, oral activated charcoal and nalfurafine, a kappa-opioid-receptor agonist. Calcific uremic arteriolopathy is triggered by an imbalance of promoters and inhibitors of vascular calcification, caused by the inflammatory changes that occur in uremia. Promising therapeutic strategies for calcific uremic arteriolopathy include bisphosphonates and intravenous sodium thiosulfate. Nephrogenic systemic fibrosis is a devastating condition associated with the use of gadolinium-based contrast agents in patients with CKD. At present, no therapies are available for this complication. Preventive measures include use of iodine-based contrast agents, particularly in patients with CKD stage 4 and 5. If gadolinium contrast is necessary, administration of low volumes of the more stable macrocyclic ionic types of gadolinium-based contrast agent is advocated. Hemodialysis following gadolinium exposure might offer benefits but evidence is lacking.

Ligand-directed nanobialys as theranostic agent for drug delivery and manganese-based magnetic resonance imaging of vascular targets

Although gadolinium has been the dominant paramagnetic metal for MR paramagnetic contrast agents, the recent association of this lanthanide with nephrogenic systemic fibrosis, an untreatable disease, has spawned renewed interest in alternative metals for MR molecular imaging. We have developed a self-assembled, manganese(III)-labeled nanobialys (1), a toroidal-shaped MR theranostic nanoparticle. In this report, Mn(III) nanobialys are characterized as MR molecular imaging agents for targeted detection of fibrin, a major biochemical feature of thrombus. A complementary ability of nanobialys to incorporate chemotherapeutic compounds with greater than 98% efficiency and to retain more than 80% of these drugs after infinite sink dissolution, point to the theranostic potential of this platform technology.